diff --git a/.biomeignore b/.biomeignore
index 5353a05..b0b03d3 100644
--- a/.biomeignore
+++ b/.biomeignore
@@ -1,18 +1,18 @@
-# Build output
-out/
-dist/
-
-# Dependencies
-node_modules/
-
-# Type definitions
-**/*.d.ts
-
-# Config files
-webpack.config.js
-
-# VSCode settings
-.vscode/
-
-# Large files
-src/encoder.json
+# Build output
+out/
+dist/
+
+# Dependencies
+node_modules/
+
+# Type definitions
+**/*.d.ts
+
+# Config files
+webpack.config.js
+
+# VSCode settings
+.vscode/
+
+# Large files
+src/encoder.json
diff --git a/.github/RELEASE.md b/.github/RELEASE.md
new file mode 100644
index 0000000..aff5140
--- /dev/null
+++ b/.github/RELEASE.md
@@ -0,0 +1,299 @@
+# Release Process Documentation
+
+## Overview
+
+This project uses an automated GitHub Actions workflow for releasing the VS Code extension. The workflow handles version bumping, building, testing, publishing to the marketplace, and creating GitHub releases.
+
+## Prerequisites
+
+### Required Secrets
+
+You need to configure the following secret in your GitHub repository:
+
+1. **`VSCE_PAT`** - Personal Access Token for VS Code Marketplace
+   - Go to [Azure DevOps](https://dev.azure.com/)
+   - Create a new organization or use existing one
+   - Navigate to User Settings → Personal Access Tokens
+   - Create a new token with the following:
+     - **Name**: VS Code Marketplace Publishing
+     - **Organization**: All accessible organizations
+     - **Expiration**: Custom (1 year recommended)
+     - **Scopes**:
+       - Marketplace → **Manage** (required)
+   - Copy the token and add it to GitHub:
+     - Repository Settings → Secrets and variables → Actions
+     - New repository secret: `VSCE_PAT`
+
+## Automated Release Workflow
+
+### Trigger
+
+The release workflow is triggered manually via GitHub Actions:
+
+1. Go to **Actions** tab in your repository
+2. Select **Release Extension** workflow
+3. Click **Run workflow**
+4. Choose version bump type:
+   - **auto** (default): Automatically determines version bump based on commits
+   - **major**: Breaking changes (1.0.0 → 2.0.0)
+   - **minor**: New features (1.1.0 → 1.2.0)
+   - **patch**: Bug fixes (1.1.0 → 1.1.1)
+
+### What the Workflow Does
+
+#### ✅ 1. Version Detection & Validation
+
+- Reads current version from `package.json`
+- Checks if version tag already exists in Git
+- Prevents duplicate releases
+
+#### ✅ 2. Commit Analysis (Auto mode)
+
+- Analyzes commits since last release
+- Determines version bump based on conventional commits:
+  - `feat!:` or `BREAKING CHANGE:` → **major**
+  - `feat:` → **minor**
+  - `fix:`, `chore:`, `docs:` → **patch**
+
+#### ✅ 3. Version Bumping
+
+- Automatically bumps version if tag exists
+- Updates `package.json` and `package-lock.json`
+- Commits changes with message: `chore: bump version to X.Y.Z`
+- Pushes version bump commit
+
+#### ✅ 4. Build & Test
+
+- Runs TypeScript type checking (`npm run type-check`)
+- Runs linter (`npm run lint:check`)
+- Compiles extension (`npm run compile`)
+- Runs test suite (`npm run test`)
+
+#### ✅ 5. Package Extension
+
+- Packages extension as `.vsix` file
+- Names file: `diffy-explain-ai-X.Y.Z.vsix`
+
+#### ✅ 6. Publish to Marketplace
+
+- Publishes extension to VS Code Marketplace
+- Uses `VSCE_PAT` secret for authentication
+- Updates existing extension listing
+
+#### ✅ 7. Create Git Tag
+
+- Creates annotated Git tag: `vX.Y.Z`
+- Pushes tag to repository
+
+#### ✅ 8. Generate Release Notes
+
+- Automatically categorizes commits:
+  - ✨ **Features**: `feat:` commits
+  - 🐛 **Bug Fixes**: `fix:` commits
+  - 📝 **Documentation**: `docs:` commits
+  - 🔧 **Maintenance**: `chore:`, `build:`, `ci:` commits
+- Includes commit hashes for traceability
+
+#### ✅ 9. Create GitHub Release
+
+- Creates GitHub Release with tag
+- Includes auto-generated release notes
+- Attaches `.vsix` file as release asset
+- Not marked as draft or prerelease
+
+#### ✅ 10. Upload Artifacts
+
+- Uploads `.vsix` file as workflow artifact
+- Retention: 90 days
+- Available for download from workflow run
+
+## Version Bump Examples
+
+### Automatic Version Bumping
+
+**Scenario 1**: Bug fixes and chores
+
+```bash
+git log v1.0.0..HEAD
+# - fix: resolve OpenAI API timeout
+# - chore: update dependencies
+# - docs: improve README
+
+Result: 1.0.0 → 1.0.1 (patch)
+```
+
+**Scenario 2**: New features
+
+```bash
+git log v1.1.0..HEAD
+# - feat: add custom commit templates
+# - fix: handle empty diffs
+
+Result: 1.1.0 → 1.2.0 (minor)
+```
+
+**Scenario 3**: Breaking changes
+
+```bash
+git log v2.0.0..HEAD
+# - feat!: redesign AI service interface
+# - BREAKING CHANGE: remove deprecated methods
+
+Result: 2.0.0 → 3.0.0 (major)
+```
+
+### Manual Version Bumping
+
+You can override automatic detection:
+
+1. **Patch Release**: Bug fixes only
+   - Select `patch` in workflow input
+   - 1.1.0 → 1.1.1
+
+2. **Minor Release**: New features
+   - Select `minor` in workflow input
+   - 1.1.0 → 1.2.0
+
+3. **Major Release**: Breaking changes
+   - Select `major` in workflow input
+   - 1.1.0 → 2.0.0
+
+## Manual Release Process
+
+If you need to release manually:
+
+### 1. Update Version
+
+```bash
+npm version patch  # or minor, major
+```
+
+### 2. Build Extension
+
+```bash
+npm run type-check
+npm run lint
+npm run compile
+```
+
+### 3. Package Extension
+
+```bash
+npm install -g @vscode/vsce
+vsce package
+```
+
+### 4. Publish to Marketplace
+
+```bash
+vsce publish -p YOUR_PERSONAL_ACCESS_TOKEN
+```
+
+### 5. Create GitHub Release
+
+```bash
+git tag -a v1.1.0 -m "Release v1.1.0"
+git push origin v1.1.0
+
+# Then create release on GitHub with VSIX file
+```
+
+## Troubleshooting
+
+### Error: "Tag already exists"
+
+The workflow checks if a tag exists and automatically bumps the version. If you see this error:
+
+1. Check existing tags: `git tag -l`
+2. Delete tag if needed: `git tag -d vX.Y.Z && git push origin :refs/tags/vX.Y.Z`
+3. Re-run workflow
+
+### Error: "VSCE_PAT is not set"
+
+1. Verify secret exists in repository settings
+2. Ensure it's named exactly `VSCE_PAT`
+3. Generate new token if expired
+
+### Error: "Extension validation failed"
+
+1. Check `package.json` for required fields
+2. Ensure `engines.vscode` matches `@types/vscode`
+3. Verify all files referenced in `package.json` exist
+
+### Tests Failed
+
+Tests failures won't block the release (marked as `continue-on-error`), but you should:
+
+1. Review test failures in workflow logs
+2. Fix failing tests
+3. Consider making tests blocking by removing `continue-on-error: true`
+
+## Best Practices
+
+### Commit Messages
+
+Use conventional commits for automatic version bumping:
+
+```bash
+# Features (minor bump)
+git commit -m "feat: add new AI model support"
+git commit -m "feat(git): implement file filtering"
+
+# Bug fixes (patch bump)
+git commit -m "fix: resolve memory leak in diff parser"
+git commit -m "fix(ai): handle API rate limiting"
+
+# Breaking changes (major bump)
+git commit -m "feat!: redesign configuration API"
+git commit -m "feat: new config format
+
+BREAKING CHANGE: Configuration schema has changed"
+
+# Other types (patch bump)
+git commit -m "docs: update installation guide"
+git commit -m "chore: update dependencies"
+git commit -m "style: format code with Biome"
+```
+
+### Release Cadence
+
+- **Patch releases**: Weekly or as needed for bug fixes
+- **Minor releases**: Monthly for new features
+- **Major releases**: Quarterly or when breaking changes necessary
+
+### Pre-Release Checklist
+
+Before triggering a release:
+
+1. ✅ Ensure all tests pass locally
+2. ✅ Update CHANGELOG.md if maintained
+3. ✅ Review open issues and PRs
+4. ✅ Test extension locally with `vsce package`
+5. ✅ Verify documentation is up to date
+
+## Monitoring
+
+### After Release
+
+Check the following:
+
+1. **Marketplace**: Extension appears at <https://marketplace.visualstudio.com/items?itemName=hitclaw.diffy-explain-ai>
+2. **GitHub Release**: Release created with VSIX file attached
+3. **Git Tag**: Tag pushed to repository
+4. **Workflow Artifacts**: VSIX available for 90 days
+
+### Rollback
+
+If you need to rollback a release:
+
+1. Unpublish from marketplace (contact VS Code team)
+2. Delete GitHub release
+3. Delete Git tag: `git push origin :refs/tags/vX.Y.Z`
+4. Revert version in `package.json`
+
+## Resources
+
+- [Publishing Extensions](https://code.visualstudio.com/api/working-with-extensions/publishing-extension)
+- [Conventional Commits](https://www.conventionalcommits.org/)
+- [Semantic Versioning](https://semver.org/)
+- [GitHub Actions Documentation](https://docs.github.com/en/actions)
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index efd624c..674d701 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,28 +1,31 @@
-name: Node.js CI
-
-on:
-  push:
-    branches: ["main"]
-  pull_request:
-    branches: ["main"]
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        node-version: [16.x, 18.x]
-        # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
-
-    steps:
-      - uses: actions/checkout@v3
-      - name: Use Node.js ${{ matrix.node-version }}
-        uses: actions/setup-node@v3
-        with:
-          node-version: ${{ matrix.node-version }}
-          cache: "npm"
-      - run: npm install
-      - run: npm run type-check
-      - run: npm run lint
-      - run: npm run compile
+name: Node.js CI
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["main"]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [16.x, 18.x]
+        # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: "npm"
+      - run: npm install
+      - run: npm run type-check
+      - run: npm run lint
+      - run: npm run compile
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..ca40f00
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,236 @@
+name: Release Extension
+
+on:
+  workflow_dispatch:
+    inputs:
+      version-bump:
+        description: "Version bump type (auto/major/minor/patch)"
+        required: false
+        default: "auto"
+        type: choice
+        options:
+          - auto
+          - major
+          - minor
+          - patch
+
+permissions:
+  contents: write
+  pull-requests: read
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # Fetch all history for version detection
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "18.x"
+          cache: "npm"
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Get current version
+        id: current-version
+        run: |
+          CURRENT_VERSION=$(node -p "require('./package.json').version")
+          echo "version=$CURRENT_VERSION" >> $GITHUB_OUTPUT
+          echo "Current version: $CURRENT_VERSION"
+
+      - name: Check if version tag exists
+        id: check-tag
+        run: |
+          if git rev-parse "v${{ steps.current-version.outputs.version }}" >/dev/null 2>&1; then
+            echo "exists=true" >> $GITHUB_OUTPUT
+            echo "Tag v${{ steps.current-version.outputs.version }} already exists"
+          else
+            echo "exists=false" >> $GITHUB_OUTPUT
+            echo "Tag v${{ steps.current-version.outputs.version }} does not exist"
+          fi
+
+      - name: Analyze commits for version bump
+        id: analyze-commits
+        if: steps.check-tag.outputs.exists == 'true' || github.event.inputs.version-bump == 'auto'
+        run: |
+          # Get commits since last tag
+          LAST_TAG=$(git describe --tags --abbrev=0 2>/dev/null || echo "")
+
+          if [ -z "$LAST_TAG" ]; then
+            echo "No previous tags found, defaulting to patch"
+            echo "bump=patch" >> $GITHUB_OUTPUT
+            exit 0
+          fi
+
+          COMMITS=$(git log $LAST_TAG..HEAD --pretty=format:"%s")
+
+          if echo "$COMMITS" | grep -qE "^(feat|feature)(\(.+\))?!:|^BREAKING CHANGE:|^[a-z]+(\(.+\))?!:"; then
+            echo "bump=major" >> $GITHUB_OUTPUT
+            echo "Detected BREAKING CHANGE - major version bump"
+          elif echo "$COMMITS" | grep -qE "^(feat|feature)(\(.+\))?:"; then
+            echo "bump=minor" >> $GITHUB_OUTPUT
+            echo "Detected feature - minor version bump"
+          else
+            echo "bump=patch" >> $GITHUB_OUTPUT
+            echo "Detected fixes/chores - patch version bump"
+          fi
+
+      - name: Determine version bump type
+        id: version-bump
+        run: |
+          if [ "${{ github.event.inputs.version-bump }}" != "auto" ] && [ -n "${{ github.event.inputs.version-bump }}" ]; then
+            echo "type=${{ github.event.inputs.version-bump }}" >> $GITHUB_OUTPUT
+            echo "Using manual version bump: ${{ github.event.inputs.version-bump }}"
+          else
+            echo "type=${{ steps.analyze-commits.outputs.bump }}" >> $GITHUB_OUTPUT
+            echo "Using automatic version bump: ${{ steps.analyze-commits.outputs.bump }}"
+          fi
+
+      - name: Bump version
+        id: bump-version
+        if: steps.check-tag.outputs.exists == 'true'
+        run: |
+          npm version ${{ steps.version-bump.outputs.type }} --no-git-tag-version
+          NEW_VERSION=$(node -p "require('./package.json').version")
+          echo "version=$NEW_VERSION" >> $GITHUB_OUTPUT
+          echo "Bumped version to: $NEW_VERSION"
+
+      - name: Set final version
+        id: final-version
+        run: |
+          if [ "${{ steps.check-tag.outputs.exists }}" == "true" ]; then
+            echo "version=${{ steps.bump-version.outputs.version }}" >> $GITHUB_OUTPUT
+          else
+            echo "version=${{ steps.current-version.outputs.version }}" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Commit version changes
+        if: steps.check-tag.outputs.exists == 'true'
+        run: |
+          git config --local user.email "github-actions[bot]@users.noreply.github.com"
+          git config --local user.name "github-actions[bot]"
+          git add package.json package-lock.json
+          git commit -m "chore: bump version to ${{ steps.final-version.outputs.version }}"
+          git push
+
+      - name: Run type check
+        run: npm run type-check
+
+      - name: Run linter
+        run: npm run lint:check
+
+      - name: Build extension
+        run: npm run compile
+
+      - name: Run tests
+        run: npm run test
+        continue-on-error: true # Don't fail release if tests fail
+
+      - name: Install vsce
+        run: npm install -g @vscode/vsce
+
+      - name: Package extension
+        run: vsce package -o diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix
+
+      - name: Publish to VS Code Marketplace
+        env:
+          VSCE_PAT: ${{ secrets.VSCE_PAT }}
+        run: vsce publish -p $VSCE_PAT --packagePath diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix
+
+      - name: Create Git tag
+        run: |
+          git tag -a "v${{ steps.final-version.outputs.version }}" -m "Release v${{ steps.final-version.outputs.version }}"
+          git push origin "v${{ steps.final-version.outputs.version }}"
+
+      - name: Generate release notes
+        id: release-notes
+        run: |
+          LAST_TAG=$(git describe --tags --abbrev=0 HEAD^ 2>/dev/null || echo "")
+
+          if [ -z "$LAST_TAG" ]; then
+            CHANGES=$(git log --pretty=format:"- %s (%h)" --no-merges)
+          else
+            CHANGES=$(git log $LAST_TAG..HEAD --pretty=format:"- %s (%h)" --no-merges)
+          fi
+
+          # Categorize changes
+          FEATURES=$(echo "$CHANGES" | grep -E "^- (feat|feature)" || echo "")
+          FIXES=$(echo "$CHANGES" | grep -E "^- fix" || echo "")
+          DOCS=$(echo "$CHANGES" | grep -E "^- docs" || echo "")
+          CHORES=$(echo "$CHANGES" | grep -E "^- (chore|build|ci)" || echo "")
+          OTHERS=$(echo "$CHANGES" | grep -vE "^- (feat|feature|fix|docs|chore|build|ci)" || echo "")
+
+          # Build release notes
+          NOTES="## What's Changed"
+
+          if [ -n "$FEATURES" ]; then
+            NOTES="$NOTES\n\n### ✨ Features\n$FEATURES"
+          fi
+
+          if [ -n "$FIXES" ]; then
+            NOTES="$NOTES\n\n### 🐛 Bug Fixes\n$FIXES"
+          fi
+
+          if [ -n "$DOCS" ]; then
+            NOTES="$NOTES\n\n### 📝 Documentation\n$DOCS"
+          fi
+
+          if [ -n "$CHORES" ]; then
+            NOTES="$NOTES\n\n### 🔧 Maintenance\n$CHORES"
+          fi
+
+          if [ -n "$OTHERS" ]; then
+            NOTES="$NOTES\n\n### Other Changes\n$OTHERS"
+          fi
+
+          # Save to file for GitHub Release
+          echo -e "$NOTES" > release-notes.md
+
+          echo "Generated release notes:"
+          cat release-notes.md
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: v${{ steps.final-version.outputs.version }}
+          name: Release v${{ steps.final-version.outputs.version }}
+          body_path: release-notes.md
+          files: diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix
+          draft: false
+          prerelease: false
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Upload VSIX artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: diffy-explain-ai-${{ steps.final-version.outputs.version }}
+          path: diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix
+          retention-days: 90
+          if-no-files-found: error
+
+      - name: Release summary
+        run: |
+          echo "## 🎉 Release Complete!" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "- **Version**: v${{ steps.final-version.outputs.version }}" >> $GITHUB_STEP_SUMMARY
+          echo "- **Extension Package**: diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix" >> $GITHUB_STEP_SUMMARY
+          echo "- **Marketplace**: Published ✅" >> $GITHUB_STEP_SUMMARY
+          echo "- **GitHub Release**: Created ✅" >> $GITHUB_STEP_SUMMARY
+          echo "- **Git Tag**: v${{ steps.final-version.outputs.version }} ✅" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "### 📦 Install" >> $GITHUB_STEP_SUMMARY
+          echo "\`\`\`bash" >> $GITHUB_STEP_SUMMARY
+          echo "# From VS Code Marketplace" >> $GITHUB_STEP_SUMMARY
+          echo "code --install-extension hitclaw.diffy-explain-ai" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "# Or download VSIX from GitHub Release" >> $GITHUB_STEP_SUMMARY
+          echo "code --install-extension diffy-explain-ai-${{ steps.final-version.outputs.version }}.vsix" >> $GITHUB_STEP_SUMMARY
+          echo "\`\`\`" >> $GITHUB_STEP_SUMMARY
diff --git a/.gitignore b/.gitignore
index 0b60dfa..bddd37a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,38 @@ dist
 node_modules
 .vscode-test/
 *.vsix
+
+# macOS
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+# Editor directories and files
+.idea
+*.swp
+*.swo
+*~
+.vscode/*
+!.vscode/extensions.json
+!.vscode/launch.json
+!.vscode/settings.json
+!.vscode/tasks.json
diff --git a/.prettierrc b/.prettierrc
deleted file mode 100644
index 9e26dfe..0000000
--- a/.prettierrc
+++ /dev/null
@@ -1 +0,0 @@
-{}
\ No newline at end of file
diff --git a/.vscode/launch.json b/.vscode/launch.json
index 64d7097..19772a1 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -9,25 +9,16 @@
       "name": "Run Extension",
       "type": "extensionHost",
       "request": "launch",
-      "args": [
-        "--extensionDevelopmentPath=${workspaceFolder}",
-      ],
-      "outFiles": [
-        "${workspaceFolder}/dist/**/*.js"
-      ],
+      "args": ["--extensionDevelopmentPath=${workspaceFolder}"],
+      "outFiles": ["${workspaceFolder}/dist/**/*.js"],
       "preLaunchTask": "${defaultBuildTask}"
     },
     {
       "name": "Run Extension (Disable Other Extentions)",
       "type": "extensionHost",
       "request": "launch",
-      "args": [
-        "--extensionDevelopmentPath=${workspaceFolder}",
-        "--disable-extensions"
-      ],
-      "outFiles": [
-        "${workspaceFolder}/dist/**/*.js"
-      ],
+      "args": ["--extensionDevelopmentPath=${workspaceFolder}", "--disable-extensions"],
+      "outFiles": ["${workspaceFolder}/dist/**/*.js"],
       "preLaunchTask": "${defaultBuildTask}"
     },
     {
@@ -38,11 +29,8 @@
         "--extensionDevelopmentPath=${workspaceFolder}",
         "--extensionTestsPath=${workspaceFolder}/out/test/suite/index"
       ],
-      "outFiles": [
-        "${workspaceFolder}/out/**/*.js",
-        "${workspaceFolder}/dist/**/*.js"
-      ],
+      "outFiles": ["${workspaceFolder}/out/**/*.js", "${workspaceFolder}/dist/**/*.js"],
       "preLaunchTask": "tasks: watch-tests"
     }
   ]
-}
\ No newline at end of file
+}
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 6b66808..2e44d85 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -10,5 +10,8 @@
   },
   // Turn off tsc task auto detection since we have the necessary tasks as npm scripts
   "typescript.tsc.autoDetect": "off",
-  "cSpell.words": ["Diffy", "GCMG"]
+  "cSpell.words": ["Diffy", "GCMG"],
+  // Use Biome as the default formatter
+  "editor.defaultFormatter": "biomejs.biome",
+  "editor.formatOnSave": true
 }
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
index c2ab68a..9e3300b 100644
--- a/.vscode/tasks.json
+++ b/.vscode/tasks.json
@@ -1,40 +1,37 @@
 // See https://go.microsoft.com/fwlink/?LinkId=733558
 // for the documentation about the tasks.json format
 {
-	"version": "2.0.0",
-	"tasks": [
-		{
-			"type": "npm",
-			"script": "watch",
-			"problemMatcher": "$ts-webpack-watch",
-			"isBackground": true,
-			"presentation": {
-				"reveal": "never",
-				"group": "watchers"
-			},
-			"group": {
-				"kind": "build",
-				"isDefault": true
-			}
-		},
-		{
-			"type": "npm",
-			"script": "watch-tests",
-			"problemMatcher": "$tsc-watch",
-			"isBackground": true,
-			"presentation": {
-				"reveal": "never",
-				"group": "watchers"
-			},
-			"group": "build"
-		},
-		{
-			"label": "tasks: watch-tests",
-			"dependsOn": [
-				"npm: watch",
-				"npm: watch-tests"
-			],
-			"problemMatcher": []
-		}
-	]
+  "version": "2.0.0",
+  "tasks": [
+    {
+      "type": "npm",
+      "script": "watch",
+      "problemMatcher": "$ts-webpack-watch",
+      "isBackground": true,
+      "presentation": {
+        "reveal": "never",
+        "group": "watchers"
+      },
+      "group": {
+        "kind": "build",
+        "isDefault": true
+      }
+    },
+    {
+      "type": "npm",
+      "script": "watch-tests",
+      "problemMatcher": "$tsc-watch",
+      "isBackground": true,
+      "presentation": {
+        "reveal": "never",
+        "group": "watchers"
+      },
+      "group": "build"
+    },
+    {
+      "label": "tasks: watch-tests",
+      "dependsOn": ["npm: watch", "npm: watch-tests"],
+      "problemMatcher": []
+    }
+  ]
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec694de..3c3a713 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,43 +1,70 @@
-# Change Log
-
-All notable changes to the "diffy-explain-ai" extension will be documented in this file.
-
-Check [Keep a Changelog](http://keepachangelog.com/) for recommendations on how to structure this file.
-
-## [Unreleased]
-
-- Initial release
-
-## [0.0.6] - 2022-12-24
-
-### Added
-
-- Generate Commit Message.
-- Explain Changes in Natural Language.
-- Directly Generate Commit Message to VScode git commit input box. Copy to Clipboard
-
-## [0.0.7] - 2022-12-24
-
-### Fixed
-
-- Commit Message Generation Improved
-
-## [0.0.8] - 2022-12-24
-
-### Changes
-
-- Suggested Message as Newline Instead of Space
-
-## [0.0.9] - 2022-12-24
-
-### Added
-
-- Explain and Preview Changes of Staged Files
-### Changes
-
-- Bug Fixes
-
-## [0.0.10] - 2022-12-24
-### Changes
-
+# Change Log
+
+All notable changes to the "diffy-explain-ai" extension will be documented in this file.
+
+Check [Keep a Changelog](http://keepachangelog.com/) for recommendations on how to structure this file.
+
+## [1.1.0] - 2025-11-03
+
+### Added
+
+- **VS Code Language Model API Integration**: Support for GitHub Copilot as an AI service provider
+- New configuration option `aiServiceProvider` to choose between OpenAI and VS Code LM
+- New configuration option `vscodeLmModel` to select between `copilot-gpt-4o` and `copilot-gpt-3.5-turbo`
+- Dual AI provider architecture allowing users to switch between OpenAI API and GitHub Copilot
+
+### Changed
+
+- Updated VS Code engine requirement to ^1.90.0 for Language Model API support
+- Improved singleton pattern implementation in service classes
+- Modernized imports with `node:` protocol for Node.js built-in modules
+- Enhanced type safety with better TypeScript type definitions
+
+### Fixed
+
+- Fixed singleton constructor patterns in OpenAiService, WorkspaceService, and VsCodeLlmService
+- Fixed confusing void type in EventEmitter type definitions
+- Removed unused variables and parameters warnings
+
+### Documentation
+
+- Updated README with instructions for both OpenAI and GitHub Copilot setup
+- Added comprehensive configuration guide for dual AI provider support
+
+## [Unreleased]
+
+- Initial release
+
+## [0.0.6] - 2022-12-24
+
+### Added
+
+- Generate Commit Message.
+- Explain Changes in Natural Language.
+- Directly Generate Commit Message to VScode git commit input box. Copy to Clipboard
+
+## [0.0.7] - 2022-12-24
+
+### Fixed
+
+- Commit Message Generation Improved
+
+## [0.0.8] - 2022-12-24
+
+### Changes
+
+- Suggested Message as Newline Instead of Space
+
+## [0.0.9] - 2022-12-24
+
+### Added
+
+- Explain and Preview Changes of Staged Files
+### Changes
+
+- Bug Fixes
+
+## [0.0.10] - 2022-12-24
+### Changes
+
 - Bug Fixes
\ No newline at end of file
diff --git a/README.md b/README.md
index 6502e18..b0a574d 100644
--- a/README.md
+++ b/README.md
@@ -1,62 +1,152 @@
-<h1 align="center">
-  <br> <a href="https://marketplace.visualstudio.com/items?itemName=hitclaw.diffy-explain-ai">
-  <img src="https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/icons/icon_512.png" alt="DIFFY" width="200"></a>
-  <br>
-  DIFFY COMMIT AI - Generate Your Commit Message or Explains the Changes 
-  <br>
-</h1>
-
-<h4 align="center">Generate Commit Message the changed code using git diff and <a href="https://openai.com/" target="_blank">OpenAI</a> in natural language .</h4>
-<br>
-<p align="center">
-
-  <a href="https://marketplace.visualstudio.com/items?itemName=hitclaw.diffy-explain-ai">
-    <img alt="Visual Studio Marketplace Downloads" src="https://img.shields.io/visual-studio-marketplace/d/hitclaw.diffy-explain-ai?label=Visual%20Studio%20Marketplace">
-  </a>
-  <a href="#">
-    <img src="https://github.com/Hi7cl4w/diffy-explain-ai/actions/workflows/main.yml/badge.svg"
-         alt="CI">
-  </a>
-  <a href="#">
-    <img src="https://img.shields.io/badge/License-MIT-blue"
-         alt="visual-studio marketplace">
-  </a>
-</p>
-
-> Generate Commit &nbsp;
-
-![screenshot](https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/images/generate_commit.gif)
-
-> Explain and Preview Changes of Staged Files &nbsp;
-
-![screenshot](https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/images/explain_and_preview.png)
-
-## Key Features
-
-- Generate Commit Message.
-- Explain Changes in Natural Language.
-- Directly Generate Commit Message to VScode git commit input box.
-- Copy to clipboard
-
-## Configure
-
-Go to Settings > Diffy - Explains Git Changes > Enter Your Api Key from OpenAI [Go to API Key Page](https://beta.openai.com/account/api-keys)
-
-## Commands
-
-- `diffy-explain-ai.generateCommitMessage` : Generate Commit Message to Commit Input Box
-- `diffy-explain-ai.explainDiffClipboard` : Explain Changes and Copy to Clipboard
-- `diffy-explain-ai.generateCommitMessageClipboard` : Generate Commit Message and Copy to Clipboard
-- `diffy-explain-ai.explainAndPreview` : Explain and Preview Changes of Staged Files
-
-## Support
-
-[!["Buy Me A Coffee"](https://www.buymeacoffee.com/assets/img/custom_images/orange_img.png)](https://www.buymeacoffee.com/manukn)
-
-## License
-
-MIT
-
----
-
-> GitHub [@Hi7cl4w](https://github.com/Hi7cl4w) &nbsp;
+<h1 align="center">
+  <br> <a href="https://marketplace.visualstudio.com/items?itemName=hitclaw.diffy-explain-ai">
+  <img src="https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/icons/icon_512.png" alt="DIFFY" width="200"></a>
+  <br>
+  DIFFY COMMIT AI - Generate Your Commit Message or Explains the Changes
+  <br>
+</h1>
+
+<h4 align="center">Generate Commit Message for the changed code using git diff and AI (<a href="https://openai.com/" target="_blank">OpenAI</a> or <a href="https://github.com/features/copilot" target="_blank">GitHub Copilot</a>) in natural language.</h4>
+<br>
+<p align="center">
+
+  <a href="https://marketplace.visualstudio.com/items?itemName=hitclaw.diffy-explain-ai">
+    <img alt="Visual Studio Marketplace Downloads" src="https://img.shields.io/visual-studio-marketplace/d/hitclaw.diffy-explain-ai?label=Visual%20Studio%20Marketplace">
+  </a>
+  <a href="#">
+    <img src="https://github.com/Hi7cl4w/diffy-explain-ai/actions/workflows/main.yml/badge.svg"
+         alt="CI">
+  </a>
+  <a href="#">
+    <img src="https://img.shields.io/badge/License-MIT-blue"
+         alt="visual-studio marketplace">
+  </a>
+</p>
+
+> Generate Commit &nbsp;
+
+![screenshot](https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/images/generate_commit.gif)
+
+> Explain and Preview Changes of Staged Files &nbsp;
+
+![screenshot](https://raw.githubusercontent.com/Hi7cl4w/diffy-explain-ai/main/images/explain_and_preview.png)
+
+## Key Features
+
+- Generate Commit Message using **OpenAI** or **VS Code Language Models (GitHub Copilot)**.
+- **Intelligent Code Indexing**: Automatically filters out irrelevant files (lock files, images, etc.) to improve AI analysis quality and reduce token usage.
+- **Customizable Commit Formats**: Choose between Conventional Commits or Gitmoji styles.
+- **Configurable Message Length**: Set maximum subject line length (50-200 characters).
+- **Optional Detailed Bodies**: Include explanatory bullet points in commit messages.
+- Explain Changes in Natural Language.
+- Directly Generate Commit Message to VScode git commit input box.
+- Copy to clipboard
+- Choose between OpenAI API or GitHub Copilot as your AI provider
+
+## Configure
+
+### Option 1: Using OpenAI (Default)
+
+1. Go to Settings > Diffy - Explains Git Changes
+2. Set **AI Service Provider** to `openai`
+3. Enter Your API Key from OpenAI [Go to API Key Page](https://beta.openai.com/account/api-keys)
+
+### Option 2: Using VS Code Language Models (GitHub Copilot)
+
+1. Go to Settings > Diffy - Explains Git Changes
+2. Set **AI Service Provider** to `vscode-lm`
+3. Ensure GitHub Copilot is installed and you are signed in
+4. Optionally select your preferred model:
+   - `copilot-gpt-4o` (default, recommended)
+   - `copilot-gpt-3.5-turbo`
+
+**Note:** Using VS Code Language Models requires an active GitHub Copilot subscription.
+
+## Advanced Configuration
+
+### Commit Message Customization
+
+#### Commit Format Style
+Choose between two popular commit message formats:
+- **Conventional Commits** (default): `feat: add user authentication`
+- **Gitmoji**: `✨ feat: add user authentication`
+
+Set in: `Settings > Diffy > Commit Message Type`
+
+#### Include Commit Body
+Enable detailed commit messages with explanatory bullet points:
+```
+feat: add user authentication
+
+- Implement JWT token generation
+- Add login and registration endpoints
+- Create user model and database schema
+```
+
+Set in: `Settings > Diffy > Include Commit Body`
+
+#### Maximum Subject Line Length
+Configure the maximum character length for commit subjects (default: 72)
+- **50**: Strict GitHub standard
+- **72**: Common standard (recommended)
+- **100**: Relaxed limit
+
+Set in: `Settings > Diffy > Max Commit Message Length`
+
+### File Filtering
+
+Exclude specific files or patterns from AI analysis to improve quality and reduce token usage:
+
+**Default exclusions:**
+- Lock files: `package-lock.json`, `yarn.lock`, `pnpm-lock.yaml`
+- Images: `*.jpg`, `*.png`, `*.gif`, `*.svg`, `*.ico`
+- Fonts: `*.woff`, `*.woff2`, `*.ttf`, `*.eot`
+
+**Add custom exclusions:**
+Set in: `Settings > Diffy > Exclude Files From Diff`
+
+Example patterns:
+- `*.min.js` - Exclude minified JavaScript
+- `dist/**` - Exclude build directory
+- `**/*.log` - Exclude all log files
+
+### Custom AI Instructions
+
+Override the default prompt with your own instructions for commit message generation:
+
+Set in: `Settings > Diffy > AI Instructions`
+
+Example:
+```
+Follow my team's commit convention:
+- Use JIRA ticket numbers in scope
+- Always include "BREAKING CHANGE" footer when applicable
+- Mention affected services
+```
+
+## Commands
+
+- `diffy-explain-ai.generateCommitMessage` : Generate Commit Message to Commit Input Box
+- `diffy-explain-ai.explainDiffClipboard` : Explain Changes and Copy to Clipboard
+- `diffy-explain-ai.generateCommitMessageClipboard` : Generate Commit Message and Copy to Clipboard
+- `diffy-explain-ai.explainAndPreview` : Explain and Preview Changes of Staged Files
+
+## Contributing & Development
+
+For contributors and maintainers:
+
+- **Release Process**: See [.github/RELEASE.md](.github/RELEASE.md) for detailed information about our automated release workflow
+- **CI/CD**: We use GitHub Actions for continuous integration and automated releases
+- **Code Quality**: All code must pass TypeScript type checking, Biome linting, and formatting before merging
+
+## Support
+
+[!["Buy Me A Coffee"](https://www.buymeacoffee.com/assets/img/custom_images/orange_img.png)](https://www.buymeacoffee.com/manukn)
+
+## License
+
+MIT
+
+---
+
+> GitHub [@Hi7cl4w](https://github.com/Hi7cl4w) &nbsp;
diff --git a/package.json b/package.json
index 10bbbc7..0bba088 100644
--- a/package.json
+++ b/package.json
@@ -2,17 +2,14 @@
   "name": "diffy-explain-ai",
   "displayName": "Diffy Commit AI - Generate Your Commit Message",
   "description": "Generate Commit Message for You or Explains The Changed Code Using Git Diff And OpenAi In Natural Language",
-  "version": "1.0.17",
+  "version": "1.1.0",
   "publisher": "hitclaw",
   "engines": {
-    "vscode": "^1.90.0"
+    "vscode": "^1.105.0"
   },
   "categories": [
     "SCM Providers"
   ],
-  "activationEvents": [
-    "onCommand:diffy-explain-ai.generateCommitMessage"
-  ],
   "repository": {
     "url": "https://github.com/Hi7cl4w/diffy-explain-ai.git"
   },
@@ -103,11 +100,29 @@
         "diffy-explain-ai.vscodeLmModel": {
           "type": "string",
           "enum": [
+            "auto",
             "copilot-gpt-4o",
-            "copilot-gpt-3.5-turbo"
+            "copilot-gpt-4",
+            "copilot-gpt-4-turbo",
+            "copilot-gpt-3.5-turbo",
+            "copilot-gpt-3.5",
+            "copilot-o1",
+            "copilot-o1-mini",
+            "copilot-o1-preview"
+          ],
+          "enumDescriptions": [
+            "Automatically selects the best available model (recommended)",
+            "GitHub Copilot GPT-4o model - Latest and most capable",
+            "GitHub Copilot GPT-4 model - High capability model",
+            "GitHub Copilot GPT-4 Turbo model - Fast and capable",
+            "GitHub Copilot GPT-3.5 Turbo model - Fast and efficient",
+            "GitHub Copilot GPT-3.5 model - Standard capability",
+            "GitHub Copilot o1 model - Advanced reasoning model",
+            "GitHub Copilot o1-mini model - Compact reasoning model",
+            "GitHub Copilot o1-preview model - Preview of o1 capabilities"
           ],
-          "default": "copilot-gpt-4o",
-          "markdownDescription": "Select the VS Code Language Model to use when `aiServiceProvider` is set to `vscode-lm`. Requires GitHub Copilot subscription."
+          "default": "auto",
+          "markdownDescription": "Select the VS Code Language Model to use when `aiServiceProvider` is set to `vscode-lm`. Requires GitHub Copilot subscription. \n\nAvailable models may vary based on your Copilot subscription tier:\n\n- **auto**: Automatically selects the best available model\n- **copilot-gpt-4o**: Latest GPT-4o model (recommended for most users)\n- **copilot-gpt-4**: GPT-4 model with high reasoning capabilities\n- **copilot-gpt-4-turbo**: Fast GPT-4 Turbo model\n- **copilot-gpt-3.5-turbo**: Fast and efficient GPT-3.5 Turbo\n- **copilot-gpt-3.5**: Standard GPT-3.5 model\n- **copilot-o1**: Advanced o1 reasoning model (may require higher tier)\n- **copilot-o1-mini**: Compact o1-mini model\n- **copilot-o1-preview**: Preview access to o1 capabilities"
         },
         "diffy-explain-ai.proxyUrl": {
           "type": "string",
@@ -136,6 +151,59 @@
         "diffy-explain-ai.aiInstructions": {
           "type": "string",
           "default": "Analyze the provided git diff --staged output, categorize the changes into a conventional commit type (e.g., feat, fix, docs, chore,style), determine if a scope is applicable, and then synthesize a concise commit message that follows the format  <type>[optional scope]: <description> [optional body] [optional footer(s)]"
+        },
+        "diffy-explain-ai.commitMessageType": {
+          "type": "string",
+          "enum": [
+            "conventional",
+            "gitmoji",
+            "custom"
+          ],
+          "enumDescriptions": [
+            "Conventional Commits format: <type>[optional scope]: <description>",
+            "Gitmoji format with emoji prefixes: 🎨 :<emoji>: <description>",
+            "Custom user-defined format using a template with placeholders"
+          ],
+          "default": "conventional",
+          "markdownDescription": "Choose the commit message format style:\n\n- **conventional**: Standard Conventional Commits format (e.g., `feat: add new feature`)\n- **gitmoji**: Commits with emoji prefixes (e.g., `✨ feat: add new feature`)\n- **custom**: Fully customizable template with placeholders (configure via Custom Commit Prompt setting)"
+        },
+        "diffy-explain-ai.customCommitPrompt": {
+          "type": "string",
+          "default": "Generate a commit message for the following git diff.\n\nRequirements:\n- Maximum subject length: {maxLength} characters\n- Use imperative mood\n- Be concise and clear{bodyInstructions}\n\nReturn ONLY the commit message, no explanations.",
+          "markdownDescription": "Custom commit message generation prompt when **Commit Message Type** is set to `custom`. \n\nSupported placeholders:\n- `{maxLength}` - Maximum subject line length\n- `{bodyInstructions}` - Auto-filled based on Include Commit Body setting\n- `{locale}` - Language/locale for the message\n- `{diff}` - The actual git diff (automatically appended)\n\nExample template:\n```\nGenerate a {locale} commit message following our team convention:\n- Start with JIRA ticket: [PROJ-XXX]\n- Subject max {maxLength} chars\n- Include impact analysis{bodyInstructions}\n```"
+        },
+        "diffy-explain-ai.includeCommitBody": {
+          "type": "boolean",
+          "default": false,
+          "markdownDescription": "Include a detailed body section in commit messages with bullet points explaining the changes. When enabled, commit messages will have:\n\n```\nfeat: add user authentication\n\n- Implement JWT token generation\n- Add login and registration endpoints\n- Create user model and database schema\n```"
+        },
+        "diffy-explain-ai.excludeFilesFromDiff": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "default": [
+            "package-lock.json",
+            "yarn.lock",
+            "pnpm-lock.yaml",
+            "*.jpg",
+            "*.png",
+            "*.gif",
+            "*.svg",
+            "*.ico",
+            "*.woff",
+            "*.woff2",
+            "*.ttf",
+            "*.eot"
+          ],
+          "markdownDescription": "File patterns to exclude from AI analysis when generating commit messages. This helps reduce token usage and improve quality by filtering out:\n\n- Lock files (package-lock.json, yarn.lock)\n- Large binary assets (images, fonts)\n- Generated files\n\nSupports glob patterns like `*.log`, `dist/**`, `**/*.min.js`"
+        },
+        "diffy-explain-ai.maxCommitMessageLength": {
+          "type": "number",
+          "default": 72,
+          "minimum": 50,
+          "maximum": 200,
+          "markdownDescription": "Maximum character length for commit message subject line. Following best practices:\n\n- **50**: Strict GitHub standard\n- **72**: Common standard (default)\n- **100**: Relaxed limit"
         }
       }
     }
diff --git a/src/@types/EventEmitter.d.ts b/src/@types/EventEmitter.d.ts
index 321f21e..f5b2415 100644
--- a/src/@types/EventEmitter.d.ts
+++ b/src/@types/EventEmitter.d.ts
@@ -11,24 +11,15 @@ export default interface TypedEventEmitter<T> {
   on<K extends keyof T>(name: K, listener: (v: T[K]) => void): this;
   addListener<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
   once<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
-  prependListener<K extends keyof T>(
-    event: K,
-    listener: (v: T[K]) => void
-  ): this;
-  prependOnceListener<K extends keyof T>(
-    event: K,
-    listener: (v: T[K]) => void
-  ): this;
-  removeListener<K extends keyof T>(
-    event: K,
-    listener: (v: T[K]) => void
-  ): this;
+  prependListener<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
+  prependOnceListener<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
+  removeListener<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
   off<K extends keyof T>(event: K, listener: (v: T[K]) => void): this;
   removeAllListeners<K extends keyof T>(event?: K): this;
   setMaxListeners(n: number): this;
   getMaxListeners(): number;
-  listeners<K extends keyof T>(event: K): (v: T[K]) => void[];
-  rawListeners<K extends keyof T>(event: K): (v: T[K]) => void[];
+  listeners<K extends keyof T>(event: K): (v: T[K]) => undefined[];
+  rawListeners<K extends keyof T>(event: K): (v: T[K]) => undefined[];
   emit<K extends keyof T>(event: K, args: T[K]): boolean;
   eventNames<K extends keyof T>(): Array<K>;
   listenerCount<K extends keyof T>(type: K): number;
diff --git a/src/@types/extension.d.ts b/src/@types/extension.d.ts
index 774fda5..b595217 100644
--- a/src/@types/extension.d.ts
+++ b/src/@types/extension.d.ts
@@ -1,6 +1,8 @@
-export type CacheResult = any;
+import type OpenAI from "openai";
+
+export type CacheResult = string | OpenAI.Chat.Completions.ChatCompletion;
 export type CacheData = {
   entity: string;
-  data?: any;
-  result: any;
+  data?: string;
+  result: CacheResult;
 };
diff --git a/src/@types/git.d.ts b/src/@types/git.d.ts
index 086d8e9..d1896cc 100644
--- a/src/@types/git.d.ts
+++ b/src/@types/git.d.ts
@@ -5,8 +5,9 @@
 
 // https://github.com/microsoft/vscode/blob/main/extensions/git/src/api/git.d.ts
 
-import { Uri, Event, Disposable, ProviderResult, Command } from "vscode";
-export { ProviderResult } from "vscode";
+import type { Command, Disposable, Event, ProviderResult, Uri } from "vscode";
+
+export type { ProviderResult } from "vscode";
 
 export interface Git {
   readonly path: string;
@@ -177,11 +178,9 @@ export interface Repository {
 
   getObjectDetails(
     treeish: string,
-    path: string
+    path: string,
   ): Promise<{ mode: string; object: string; size: number }>;
-  detectObjectType(
-    object: string
-  ): Promise<{ mimetype: string; encoding?: string }>;
+  detectObjectType(object: string): Promise<{ mimetype: string; encoding?: string }>;
   buffer(ref: string, path: string): Promise<Buffer>;
   show(ref: string, path: string): Promise<string>;
   getCommit(ref: string): Promise<Commit>;
@@ -231,7 +230,7 @@ export interface Repository {
     remoteName?: string,
     branchName?: string,
     setUpstream?: boolean,
-    force?: ForcePushMode
+    force?: ForcePushMode,
   ): Promise<void>;
 
   blame(path: string): Promise<string>;
@@ -279,7 +278,7 @@ export interface PushErrorHandler {
     repository: Repository,
     remote: Remote,
     refspec: string,
-    error: Error & { gitErrorCode: GitErrorCodes }
+    error: Error & { gitErrorCode: GitErrorCodes },
   ): Promise<boolean>;
 }
 
@@ -307,9 +306,7 @@ export interface API {
   registerRemoteSourcePublisher(publisher: RemoteSourcePublisher): Disposable;
   registerRemoteSourceProvider(provider: RemoteSourceProvider): Disposable;
   registerCredentialsProvider(provider: CredentialsProvider): Disposable;
-  registerPostCommitCommandsProvider(
-    provider: PostCommitCommandsProvider
-  ): Disposable;
+  registerPostCommitCommandsProvider(provider: PostCommitCommandsProvider): Disposable;
   registerPushErrorHandler(handler: PushErrorHandler): Disposable;
 }
 
diff --git a/src/Diffy.ts b/src/Diffy.ts
index 45adc56..8766ddf 100644
--- a/src/Diffy.ts
+++ b/src/Diffy.ts
@@ -1,9 +1,10 @@
 import * as vscode from "vscode";
-import { env, ExtensionContext } from "vscode";
+import { type ExtensionContext, env } from "vscode";
 import { EventType } from "./@types/EventType";
 import BaseDiffy from "./BaseDiffy";
 import GitService from "./service/GitService";
 import OpenAiService from "./service/OpenAiService";
+import VsCodeLlmService from "./service/VsCodeLlmService";
 import WindowService from "./service/WindowService";
 import WorkspaceService from "./service/WorkspaceService";
 import { sendToOutput } from "./utils/log";
@@ -12,17 +13,18 @@ class Diffy extends BaseDiffy {
   static _instance: Diffy;
   private gitService: GitService | null = null;
   private _openAIService: OpenAiService | null = null;
+  private _vsCodeLlmService: VsCodeLlmService | null = null;
   private workspaceService: WorkspaceService | null = null;
   isEnabled = false;
-  private _windowsService: any;
+  private _windowsService: WindowService | null = null;
   context!: ExtensionContext;
 
   constructor(context: ExtensionContext) {
-    if (Diffy._instance) {
-      return Diffy._instance;
-    }
     super();
-    this.context = context;
+    if (!Diffy._instance) {
+      Diffy._instance = this;
+      this.context = context;
+    }
   }
 
   /**
@@ -57,6 +59,30 @@ class Diffy extends BaseDiffy {
     return this._openAIService;
   }
 
+  /**
+   * If the _vsCodeLlmService property is not defined, then create a new instance of the VsCodeLlmService
+   * class and assign it to the _vsCodeLlmService property.
+   * @returns The VsCodeLlmService object.
+   */
+  getVsCodeLlmService(): VsCodeLlmService {
+    if (!this._vsCodeLlmService) {
+      this._vsCodeLlmService = VsCodeLlmService.getInstance();
+    }
+    return this._vsCodeLlmService;
+  }
+
+  /**
+   * Gets the appropriate AI service based on user settings
+   * @returns The selected AI service (OpenAI or VS Code LLM)
+   */
+  getAIService(): AIService {
+    const provider = this.workspaceService?.getAiServiceProvider();
+    if (provider === "vscode-lm") {
+      return this.getVsCodeLlmService();
+    }
+    return this.getOpenAPIService();
+  }
+
   getWindowService(): WindowService {
     if (!this._windowsService) {
       this._windowsService = WindowService.getInstance();
@@ -71,11 +97,17 @@ class Diffy extends BaseDiffy {
     if (!this.gitService?.checkAndWarnRepoExist()) {
       return;
     }
-    /* Checking if the api key is defined. */
-    const apiKey = this.workspaceService?.getOpenAIKey();
-    if (!apiKey) {
-      return;
+
+    const provider = this.workspaceService?.getAiServiceProvider();
+
+    // Check if API key is required (for OpenAI)
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
     }
+
     /* Getting the current repo. */
     const repo = this.gitService?.getCurrentRepo();
     if (!repo) {
@@ -94,19 +126,53 @@ class Diffy extends BaseDiffy {
     if (!diff) {
       return;
     }
-    /* OpenAPI */
-    const changes = await this.getOpenAPIService().getExplainedChanges(
-      diff,
-      apiKey,
-      nameOnly
-    );
+
+    /* Get AI Service based on provider */
+    const aiService = this.getAIService();
+    let changes: string | null = null;
+
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
+      changes = await (aiService as OpenAiService).getExplainedChanges(diff, apiKey, nameOnly);
+    } else {
+      // VS Code LLM - try with fallback to OpenAI if it fails
+      try {
+        changes = await aiService.getExplainedChanges("", diff);
+      } catch (error) {
+        // If VS Code LM fails with model not supported error, try OpenAI as fallback
+        if (
+          error instanceof Error &&
+          (error.message.includes("model_not_supported") ||
+            error.message.includes("Model is not supported"))
+        ) {
+          vscode.window.showInformationMessage(
+            "VS Code Language Model not supported for this request. Falling back to OpenAI...",
+          );
+          const apiKey = this.workspaceService?.getOpenAIKey();
+          if (apiKey) {
+            changes = await this.getOpenAPIService().getExplainedChanges(diff, apiKey, nameOnly);
+          } else {
+            vscode.window.showErrorMessage(
+              "VS Code Language Model failed and no OpenAI API key configured. Please configure OpenAI API key in settings.",
+            );
+            return;
+          }
+        } else {
+          throw error; // Re-throw other errors
+        }
+      }
+    }
+
     if (changes) {
       this.getWindowService().showExplainedResultWebviewPane(changes);
     }
   }
 
   /**
-   * It takes the code that you've changed in your current git branch, sends it to OpenAI's API, and
+   * It takes the code that you've changed in your current git branch, sends it to AI service, and
    * then copies the response to your clipboard
    * @returns The return value is a string.
    */
@@ -117,11 +183,17 @@ class Diffy extends BaseDiffy {
     if (!this.gitService?.checkAndWarnRepoExist()) {
       return;
     }
-    /* Checking if the api key is defined. */
-    const apiKey = this.workspaceService?.getOpenAIKey();
-    if (!apiKey) {
-      return;
+
+    const provider = this.workspaceService?.getAiServiceProvider();
+
+    // Check if API key is required (for OpenAI)
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
     }
+
     /* Getting the current repo. */
     const repo = this.gitService?.getCurrentRepo();
     if (!repo) {
@@ -140,12 +212,46 @@ class Diffy extends BaseDiffy {
     if (!diff) {
       return;
     }
-    /* OpenAPI */
-    const changes = await this.getOpenAPIService().getExplainedChanges(
-      diff,
-      apiKey,
-      nameOnly
-    );
+
+    /* Get AI Service based on provider */
+    const aiService = this.getAIService();
+    let changes: string | null = null;
+
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
+      changes = await (aiService as OpenAiService).getExplainedChanges(diff, apiKey, nameOnly);
+    } else {
+      // VS Code LLM - try with fallback to OpenAI if it fails
+      try {
+        changes = await aiService.getExplainedChanges("", diff);
+      } catch (error) {
+        // If VS Code LM fails with model not supported error, try OpenAI as fallback
+        if (
+          error instanceof Error &&
+          (error.message.includes("model_not_supported") ||
+            error.message.includes("Model is not supported"))
+        ) {
+          vscode.window.showInformationMessage(
+            "VS Code Language Model not supported for this request. Falling back to OpenAI...",
+          );
+          const apiKey = this.workspaceService?.getOpenAIKey();
+          if (apiKey) {
+            changes = await this.getOpenAPIService().getExplainedChanges(diff, apiKey, nameOnly);
+          } else {
+            vscode.window.showErrorMessage(
+              "VS Code Language Model failed and no OpenAI API key configured. Please configure OpenAI API key in settings.",
+            );
+            return;
+          }
+        } else {
+          throw error; // Re-throw other errors
+        }
+      }
+    }
+
     /* Copying the changes to the clipboard and showing the changes in the message box. */
     if (changes) {
       env.clipboard.writeText(changes);
@@ -154,8 +260,8 @@ class Diffy extends BaseDiffy {
   }
 
   /**
-   * It takes the current git diff, sends it to OpenAI, and then copies the response to the clipboard.
-   * @returns The commit message.
+   * It takes the diff of the current branch, sends it to the AI service, and then copies the response to clipboard.
+   * @returns a promise.
    */
   async generateCommitMessageToClipboard() {
     if (!this.workspaceService?.checkAndWarnWorkSpaceExist()) {
@@ -164,10 +270,15 @@ class Diffy extends BaseDiffy {
     if (!this.gitService?.checkAndWarnRepoExist()) {
       return;
     }
-    /* Checking if the api key is defined. */
-    const apiKey = this.workspaceService?.getOpenAIKey();
-    if (!apiKey) {
-      return;
+
+    const provider = this.workspaceService?.getAiServiceProvider();
+
+    // Check if API key is required (for OpenAI)
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
     }
 
     /* Getting the current repo. */
@@ -188,12 +299,49 @@ class Diffy extends BaseDiffy {
     if (!diff) {
       return;
     }
-    /* OpenAPI */
-    const changes = await this.getOpenAPIService().getCommitMessageFromDiff(
-      diff,
-      apiKey,
-      nameOnly
-    );
+
+    /* Get AI Service based on provider */
+    let changes: string | null = null;
+
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
+      changes = await this.getOpenAPIService().getCommitMessageFromDiff(diff, apiKey, nameOnly);
+    } else {
+      // VS Code LLM - try with fallback to OpenAI if it fails
+      try {
+        changes = await this.getVsCodeLlmService().getCommitMessageFromDiff(diff, nameOnly);
+      } catch (error) {
+        // If VS Code LM fails with model not supported error, try OpenAI as fallback
+        if (
+          error instanceof Error &&
+          (error.message.includes("model_not_supported") ||
+            error.message.includes("Model is not supported"))
+        ) {
+          vscode.window.showInformationMessage(
+            "VS Code Language Model not supported for this request. Falling back to OpenAI...",
+          );
+          const apiKey = this.workspaceService?.getOpenAIKey();
+          if (apiKey) {
+            changes = await this.getOpenAPIService().getCommitMessageFromDiff(
+              diff,
+              apiKey,
+              nameOnly,
+            );
+          } else {
+            vscode.window.showErrorMessage(
+              "VS Code Language Model failed and no OpenAI API key configured. Please configure OpenAI API key in settings.",
+            );
+            return;
+          }
+        } else {
+          throw error; // Re-throw other errors
+        }
+      }
+    }
+
     if (changes) {
       env.clipboard.writeText(changes);
       this.showInformationMessage(changes);
@@ -201,7 +349,7 @@ class Diffy extends BaseDiffy {
   }
 
   /**
-   * It takes the diff of the current branch, sends it to the OpenAI API, and then sets the commit
+   * It takes the diff of the current branch, sends it to the AI service, and then sets the commit
    * message to the input box
    * @returns a promise.
    */
@@ -209,7 +357,7 @@ class Diffy extends BaseDiffy {
     progress?: vscode.Progress<{
       message?: string | undefined;
       increment?: number | undefined;
-    }>
+    }>,
   ) {
     if (!this.workspaceService?.checkAndWarnWorkSpaceExist()) {
       return;
@@ -217,10 +365,15 @@ class Diffy extends BaseDiffy {
     if (!this.gitService?.checkAndWarnRepoExist()) {
       return;
     }
-    /* Checking if the api key is defined. */
-    const apiKey = this.workspaceService?.getOpenAIKey();
-    if (!apiKey) {
-      return;
+
+    const provider = this.workspaceService?.getAiServiceProvider();
+
+    // Check if API key is required (for OpenAI)
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
     }
 
     /* Getting the current repo. */
@@ -241,13 +394,59 @@ class Diffy extends BaseDiffy {
     if (!diff) {
       return;
     }
-    /* OpenAPI */
-    const changes = await this.getOpenAPIService().getCommitMessageFromDiff(
-      diff,
-      apiKey,
-      nameOnly,
-      progress
-    );
+
+    /* Get AI Service based on provider */
+    let changes: string | null = null;
+
+    if (provider === "openai") {
+      const apiKey = this.workspaceService?.getOpenAIKey();
+      if (!apiKey) {
+        return;
+      }
+      changes = await this.getOpenAPIService().getCommitMessageFromDiff(
+        diff,
+        apiKey,
+        nameOnly,
+        progress,
+      );
+    } else {
+      // VS Code LLM - try with fallback to OpenAI if it fails
+      try {
+        changes = await this.getVsCodeLlmService().getCommitMessageFromDiff(
+          diff,
+          nameOnly,
+          progress,
+        );
+      } catch (error) {
+        // If VS Code LM fails with model not supported error, try OpenAI as fallback
+        if (
+          error instanceof Error &&
+          (error.message.includes("model_not_supported") ||
+            error.message.includes("Model is not supported"))
+        ) {
+          vscode.window.showInformationMessage(
+            "VS Code Language Model not supported for this request. Falling back to OpenAI...",
+          );
+          const apiKey = this.workspaceService?.getOpenAIKey();
+          if (apiKey) {
+            changes = await this.getOpenAPIService().getCommitMessageFromDiff(
+              diff,
+              apiKey,
+              nameOnly,
+              progress,
+            );
+          } else {
+            vscode.window.showErrorMessage(
+              "VS Code Language Model failed and no OpenAI API key configured. Please configure OpenAI API key in settings.",
+            );
+            return;
+          }
+        } else {
+          throw error; // Re-throw other errors
+        }
+      }
+    }
+
     if (changes) {
       /* Setting the commit message to the input box. */
       this.gitService?.setCommitMessageToInputBox(repo, changes);
@@ -261,6 +460,7 @@ class Diffy extends BaseDiffy {
     this.isEnabled = false;
     this.gitService = null;
     this._openAIService = null;
+    this._vsCodeLlmService = null;
     this.workspaceService = null;
   }
 }
diff --git a/src/extension.ts b/src/extension.ts
index d668b9a..0c68b45 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -10,55 +10,43 @@ export function activate(context: vscode.ExtensionContext) {
   app.init();
 
   context.subscriptions.push(
-    vscode.commands.registerCommand(
-      "diffy-explain-ai.explainDiffClipboard",
-      () => {
-        app?.explainDiffToClipboard();
-      }
-    )
+    vscode.commands.registerCommand("diffy-explain-ai.explainDiffClipboard", () => {
+      return app?.explainDiffToClipboard();
+    }),
   );
 
   context.subscriptions.push(
-    vscode.commands.registerCommand(
-      "diffy-explain-ai.generateCommitMessage",
-      async () => {
-        vscode.window.withProgress(
-          {
-            location: vscode.ProgressLocation.Notification,
-            cancellable: false,
-            title: "Generating...\n",
-          },
-          async (progress) => {
-            progress.report({ increment: 0 });
-
-            await app?.generateCommitMessageToSCM(progress);
-
-            progress.report({
-              message: "Commit message generated.",
-              increment: 100,
-            });
-          }
-        );
-      }
-    )
+    vscode.commands.registerCommand("diffy-explain-ai.generateCommitMessage", () => {
+      return vscode.window.withProgress(
+        {
+          location: vscode.ProgressLocation.Notification,
+          cancellable: false,
+          title: "Generating...\n",
+        },
+        async (progress) => {
+          progress.report({ increment: 0 });
+
+          await app?.generateCommitMessageToSCM(progress);
+
+          progress.report({
+            message: "Commit message generated.",
+            increment: 100,
+          });
+        },
+      );
+    }),
   );
 
   context.subscriptions.push(
-    vscode.commands.registerCommand(
-      "diffy-explain-ai.generateCommitMessageClipboard",
-      () => {
-        app?.generateCommitMessageToClipboard();
-      }
-    )
+    vscode.commands.registerCommand("diffy-explain-ai.generateCommitMessageClipboard", () => {
+      return app?.generateCommitMessageToClipboard();
+    }),
   );
 
   context.subscriptions.push(
-    vscode.commands.registerCommand(
-      "diffy-explain-ai.explainAndPreview",
-      () => {
-        app?.explainAndPreview();
-      }
-    )
+    vscode.commands.registerCommand("diffy-explain-ai.explainAndPreview", () => {
+      return app?.explainAndPreview();
+    }),
   );
 }
 
diff --git a/src/service/CacheService.ts b/src/service/CacheService.ts
index 0eb20d5..3b5aaab 100644
--- a/src/service/CacheService.ts
+++ b/src/service/CacheService.ts
@@ -1,4 +1,4 @@
-import { CacheData, CacheResult } from "../@types/extension";
+import type { CacheData, CacheResult } from "../@types/extension";
 
 export class CacheService {
   private static _instance: CacheService;
@@ -17,7 +17,7 @@ export class CacheService {
 
   /* A method that takes in a entity and data. It then checks if the record exists and if it
   doesn't it pushes it to the cache. */
-  public set = (entity: string, data: any, result: any): void => {
+  public set = (entity: string, data: string, result: CacheResult): void => {
     if (!this.recordExists(entity, data)) {
       this.cache.push({
         entity: entity,
@@ -29,7 +29,7 @@ export class CacheService {
 
   /* A method that takes in entity and data. It then checks if the record exists and if it
     doesn't it pushes it to the cache. */
-  public get = (entity: string, data: any): CacheResult | null => {
+  public get = (entity: string, data: string): CacheResult | null => {
     const cacheRecord = this.cache.find((x) => {
       if (data) {
         return x.entity === entity && x.data === data;
@@ -47,7 +47,7 @@ export class CacheService {
 
   /* It's a method that takes in entity and data . It then checks if the record exists and if it
       doesn't it pushes it to the cache. */
-  public recordExists = (entity: string, data: any): boolean => {
+  public recordExists = (entity: string, data: string): boolean => {
     return !!this.get(entity, data);
   };
 }
diff --git a/src/service/GitService.ts b/src/service/GitService.ts
index b097258..87057f8 100644
--- a/src/service/GitService.ts
+++ b/src/service/GitService.ts
@@ -1,8 +1,8 @@
-import { window, Extension, extensions } from "vscode";
-
-import { API as GitApi, GitExtension, Repository } from "../@types/git";
-import { CONSTANTS } from "../Constants";
 import simpleGit from "simple-git";
+import { type Extension, extensions, window } from "vscode";
+import type { API as GitApi, GitExtension, Repository } from "../@types/git";
+import { CONSTANTS } from "../Constants";
+import WorkspaceService from "./WorkspaceService";
 
 class GitService {
   static _instance: GitService;
@@ -46,9 +46,7 @@ class GitService {
     if (this.vscodeGitApi === null) {
       const api = await this.getVscodeGitApi();
       if (api === undefined) {
-        this.showErrorMessage(
-          "Please make sure git repo initiated or scm plugin working"
-        );
+        this.showErrorMessage("Please make sure git repo initiated or scm plugin working");
         this.isEnabled = false;
         return;
       }
@@ -98,20 +96,16 @@ class GitService {
     window.showInformationMessage(`${CONSTANTS.extensionShortName}: ${msg}`);
   }
 
-  async getDiffAndWarnUser(
-    repo: Repository,
-    cached = true,
-    nameOnly?: boolean
-  ) {
+  async getDiffAndWarnUser(repo: Repository, cached = true, nameOnly?: boolean) {
     const diff = await this.getGitDiff(repo, cached, nameOnly);
     if (!diff) {
       if (cached) {
         const diffUncached = await repo.diff(false);
-        diffUncached
-          ? this.showInformationMessage(
-              "warning: please stage your git changes"
-            )
-          : this.showInformationMessage("No Changes");
+        if (diffUncached) {
+          this.showInformationMessage("warning: please stage your git changes");
+        } else {
+          this.showInformationMessage("No Changes");
+        }
         return null;
       }
       this.showInformationMessage("No changes");
@@ -119,20 +113,90 @@ class GitService {
     return diff;
   }
 
+  /**
+   * Check if a file path matches any of the exclusion patterns
+   * @param filePath - The file path to check
+   * @param patterns - Array of glob patterns to match against
+   * @returns true if the file should be excluded
+   */
+  private shouldExcludeFile(filePath: string, patterns: string[]): boolean {
+    for (const pattern of patterns) {
+      // Simple glob pattern matching
+      if (pattern.includes("*")) {
+        const regex = new RegExp(
+          `^${pattern.replace(/\\/g, "\\\\").replace(/\./g, "\\.").replace(/\*/g, ".*").replace(/\?/g, ".")}$`,
+        );
+        if (regex.test(filePath)) {
+          return true;
+        }
+      } else if (filePath.includes(pattern)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Filter diff output to exclude specified file patterns
+   * @param diff - The raw git diff output
+   * @param excludePatterns - Patterns to exclude
+   * @returns Filtered diff output
+   */
+  private filterDiffByExclusions(diff: string, excludePatterns: string[]): string {
+    if (!excludePatterns || excludePatterns.length === 0) {
+      return diff;
+    }
+
+    // Split diff into file sections (each starts with "diff --git")
+    const fileSections = diff.split(/(?=diff --git)/);
+    const filteredSections: string[] = [];
+
+    for (const section of fileSections) {
+      if (!section.trim()) {
+        continue;
+      }
+
+      // Extract file path from the diff header
+      // Format: "diff --git a/path/to/file b/path/to/file"
+      const fileMatch = section.match(/diff --git a\/(.+?) b\//);
+      if (!fileMatch) {
+        // Keep sections we can't parse
+        filteredSections.push(section);
+        continue;
+      }
+
+      const filePath = fileMatch[1];
+      if (!this.shouldExcludeFile(filePath, excludePatterns)) {
+        filteredSections.push(section);
+      }
+    }
+
+    return filteredSections.join("");
+  }
+
   /**
    * Get the diff in the git repository.
    * @returns The diff object is being returned.
    */
-  async getGitDiff(repo: Repository, cachedInput = true, nameOnly?: boolean) {
+  async getGitDiff(repo: Repository, _cachedInput = true, nameOnly?: boolean) {
     // let diff = await repo.diff(cached);
     const git = simpleGit(repo.rootUri.fsPath);
     let diff: string | null = "";
+
+    // Get exclusion patterns from settings
+    const excludePatterns = WorkspaceService.getInstance().getExcludeFilesFromDiff();
+
     if (!nameOnly) {
       diff = await git.diff(["--cached"]).catch((error) => {
         this.showErrorMessage("git repository not found");
         console.error(error);
         return null;
       });
+
+      // Apply file filtering if diff was successful
+      if (diff && excludePatterns.length > 0) {
+        diff = this.filterDiffByExclusions(diff, excludePatterns);
+      }
     } else {
       diff = await git.diff(["--cached", "--name-status"]).catch((error) => {
         this.showErrorMessage("git repository not found");
@@ -150,9 +214,7 @@ class GitService {
    */
   setCommitMessageToInputBox(repo: Repository, message: string) {
     const previousValue = repo.inputBox.value;
-    repo.inputBox.value = previousValue
-      ? previousValue + " \n" + message
-      : message;
+    repo.inputBox.value = previousValue ? `${previousValue} \n${message}` : message;
   }
 
   /**
@@ -161,13 +223,9 @@ class GitService {
    */
   private async getVscodeGitApi(): Promise<GitApi | undefined> {
     try {
-      const extension = extensions.getExtension(
-        "vscode.git"
-      ) as Extension<GitExtension>;
+      const extension = extensions.getExtension("vscode.git") as Extension<GitExtension>;
       if (extension !== undefined) {
-        const gitExtension = extension.isActive
-          ? extension.exports
-          : await extension.activate();
+        const gitExtension = extension.isActive ? extension.exports : await extension.activate();
 
         return gitExtension.getAPI(1);
       }
diff --git a/src/service/OpenAiService.ts b/src/service/OpenAiService.ts
index 6e33fa1..a410ece 100644
--- a/src/service/OpenAiService.ts
+++ b/src/service/OpenAiService.ts
@@ -1,5 +1,5 @@
 import OpenAI from "openai";
-import * as vscode from "vscode";
+import type * as vscode from "vscode";
 import { window } from "vscode";
 import { clearOutput, sendToOutput } from "../utils/log";
 import { CacheService } from "./CacheService";
@@ -17,12 +17,9 @@ export interface Error {
 
 class OpenAiService implements AIService {
   static _instance: OpenAiService;
-  cacheService!: CacheService;
+  cacheService: CacheService;
 
-  constructor() {
-    if (OpenAiService._instance) {
-      return OpenAiService._instance;
-    }
+  private constructor() {
     this.cacheService = CacheService.getInstance();
   }
 
@@ -46,35 +43,22 @@ class OpenAiService implements AIService {
   async getCommitMessageFromDiff(
     code: string,
     openAIKey: string,
-    nameOnly?: boolean,
+    _nameOnly?: boolean,
     progress?: vscode.Progress<{
       message?: string | undefined;
       increment?: number | undefined;
-    }>
+    }>,
   ): Promise<string | null> {
-    let gitCmd = "git diff --cached";
-    if (nameOnly) {
-      gitCmd = "git diff --cached --name-status";
-    }
     const instructions = WorkspaceService.getInstance().getAIInstructions();
     if (!instructions) {
       return null;
     }
-    let response = await this.getFromOpenApi(
-      instructions,
-      code,
-      openAIKey,
-      progress
-    );
-    if (
-      response &&
-      response.choices.length > 0 &&
-      response.choices[0].message
-    ) {
+    const response = await this.getFromOpenApi(instructions, code, openAIKey, progress);
+    if (response && response.choices.length > 0 && response.choices[0].message) {
       let message = String(response?.choices[0].message.content);
       message = message.trim();
-      message = message.replace(/^\"/gm, "");
-      message = message.replace(/\"$/gm, "");
+      message = message.replace(/^"/gm, "");
+      message = message.replace(/"$/gm, "");
       return message;
     }
     return null;
@@ -86,11 +70,7 @@ class OpenAiService implements AIService {
    * @param {string} code - the git diff you want to get the explanation for
    * @returns The explanation of the git diff.
    */
-  async getExplainedChanges(
-    code: string,
-    openAIKey?: string,
-    nameOnly?: boolean
-  ) {
+  async getExplainedChanges(code: string, openAIKey?: string, nameOnly?: boolean) {
     let gitCmd = "git diff --cached";
     if (nameOnly) {
       gitCmd = "git diff --cached --name-status";
@@ -99,16 +79,12 @@ class OpenAiService implements AIService {
       "You are a bot explains the changes from the result of '" +
       gitCmd +
       "' that user given. commit message should be a multiple lines where first line doesn't exceeds '50' characters by following commit message guidelines based on the given git diff changes without mentioning itself";
-    let response = await this.getFromOpenApi(instructions, code, openAIKey);
-    if (
-      response &&
-      response.choices.length > 0 &&
-      response.choices[0].message
-    ) {
+    const response = await this.getFromOpenApi(instructions, code, openAIKey);
+    if (response && response.choices.length > 0 && response.choices[0].message) {
       let message = String(response?.choices[0].message.content);
       message = message.trim();
-      message = message.replace(/^\"/gm, "");
-      message = message.replace(/\"$/gm, "");
+      message = message.replace(/^"/gm, "");
+      message = message.replace(/"$/gm, "");
       return message;
     }
     return null;
@@ -127,7 +103,7 @@ class OpenAiService implements AIService {
     progress?: vscode.Progress<{
       message?: string | undefined;
       increment?: number | undefined;
-    }>
+    }>,
   ) {
     const openAiClient = new OpenAI({ apiKey: openAIKey });
     const model = WorkspaceService.getInstance().getGptModel();
@@ -135,7 +111,7 @@ class OpenAiService implements AIService {
     if (exist) {
       const result = this.cacheService.get(
         model,
-        instructions + prompt
+        instructions + prompt,
       ) as OpenAI.Chat.Completions.ChatCompletion;
       sendToOutput(`result: ${JSON.stringify(result)}`);
       return result;
@@ -174,58 +150,74 @@ class OpenAiService implements AIService {
     sendToOutput(`model: ${params.model}`);
     sendToOutput(`max_tokens: ${params.max_tokens}`);
     sendToOutput(`temperature: ${params.temperature}`);
-    const response = await openAiClient.chat.completions
-      .create(params)
-      .then((value) => {
-        sendToOutput(`result success: ${JSON.stringify(value)}`);
-        progress?.report({ increment: 49 });
-        return value;
-      })
-      .catch(async (reason) => {
-        console.error(reason.response);
-        sendToOutput(`result failed: ${JSON.stringify(reason)}`);
-        if (typeof reason === "string" || reason instanceof String) {
-          window.showErrorMessage(`OpenAI Error: ${reason} `);
-          return undefined;
-        }
+
+    let response: OpenAI.Chat.Completions.ChatCompletion | undefined;
+    try {
+      response = await openAiClient.chat.completions.create(params);
+      sendToOutput(`result success: ${JSON.stringify(response)}`);
+      progress?.report({ increment: 49 });
+    } catch (reason: unknown) {
+      console.error(reason);
+      sendToOutput(`result failed: ${JSON.stringify(reason)}`);
+
+      // Type guard for error with response property
+      const hasResponse = (
+        err: unknown,
+      ): err is {
+        response?: {
+          statusText?: string;
+          status?: number;
+          data?: { error?: { message?: string; type?: string } };
+        };
+      } => {
+        return typeof err === "object" && err !== null && "response" in err;
+      };
+
+      if (typeof reason === "string" || reason instanceof String) {
+        window.showErrorMessage(`OpenAI Error: ${reason} `);
+        return undefined;
+      }
+
+      if (hasResponse(reason)) {
         if (reason.response?.statusText) {
           window.showErrorMessage(
-            `OpenAI Error: ${
-              reason.response?.data.error?.message || reason.response.statusText
-            } `
+            `OpenAI Error: ${reason.response?.data?.error?.message || reason.response.statusText} `,
           );
         } else {
           window.showErrorMessage("OpenAI Error");
         }
-        if (reason?.response?.status && openAIKey) {
-          if (reason?.response?.status === 429) {
+
+        if (reason.response?.status && openAIKey) {
+          if (reason.response.status === 429) {
             window.showInformationMessage(
-              "Caution: In case the API key has expired, please remove it from the extension settings in order to continue using the default proxy server."
+              "Caution: In case the API key has expired, please remove it from the extension settings in order to continue using the default proxy server.",
             );
             // return await this.getFromOpenApi(prompt, undefined, progress);
           }
         }
-        if (reason.response?.data.error?.type === "invalid_request_error") {
+
+        if (reason.response?.data?.error?.type === "invalid_request_error") {
           window.showErrorMessage(
-            "Diffy Error: There was an issue. Server is experiencing downtime/busy. Please try again later."
+            "Diffy Error: There was an issue. Server is experiencing downtime/busy. Please try again later.",
           );
           progress?.report({
             increment: 1,
             message: "\nFailed.",
           });
-        } else if (reason.response?.data.error?.message) {
-          window.showErrorMessage(
-            `Diffy Error: ${reason.response?.data.error?.message}`
-          );
+        } else if (reason.response?.data?.error?.message) {
+          window.showErrorMessage(`Diffy Error: ${reason.response.data.error.message}`);
           progress?.report({
             increment: 1,
             message: "\nFailed.",
           });
         }
-        return undefined;
-      });
+      } else {
+        window.showErrorMessage("OpenAI Error");
+      }
+
+      return undefined;
+    }
     if (
-      response &&
       response?.choices[0].message.content &&
       response?.choices[0].message.content !== "" &&
       response?.choices[0].message.content !== "\n"
diff --git a/src/service/VsCodeLlmService.ts b/src/service/VsCodeLlmService.ts
index 8733988..5da991f 100644
--- a/src/service/VsCodeLlmService.ts
+++ b/src/service/VsCodeLlmService.ts
@@ -6,12 +6,9 @@ import WorkspaceService from "./WorkspaceService";
 
 class VsCodeLlmService implements AIService {
   static _instance: VsCodeLlmService;
-  cacheService!: CacheService;
+  cacheService: CacheService;
 
-  constructor() {
-    if (VsCodeLlmService._instance) {
-      return VsCodeLlmService._instance;
-    }
+  private constructor() {
     this.cacheService = CacheService.getInstance();
   }
 
@@ -35,30 +32,126 @@ class VsCodeLlmService implements AIService {
    */
   async getCommitMessageFromDiff(
     code: string,
-    nameOnly?: boolean,
+    _nameOnly?: boolean,
     progress?: vscode.Progress<{
       message?: string | undefined;
       increment?: number | undefined;
-    }>
+    }>,
   ): Promise<string | null> {
-    const instructions = WorkspaceService.getInstance().getAIInstructions();
-    if (!instructions) {
-      return null;
+    const workspaceService = WorkspaceService.getInstance();
+    const commitType = workspaceService.getCommitMessageType();
+    const includeBody = workspaceService.getIncludeCommitBody();
+    const maxLength = workspaceService.getMaxCommitMessageLength();
+    const customInstructions = workspaceService.getAIInstructions();
+
+    // Build enhanced prompt based on commit type and settings
+    let instructions = "";
+
+    if (commitType === "custom") {
+      // Custom user-defined template with placeholder replacement
+      const customTemplate = workspaceService.getCustomCommitPrompt();
+
+      // Prepare body instructions based on includeBody setting
+      const bodyInstructions = includeBody
+        ? "\n- Include a body section with 2-4 bullet points explaining the changes"
+        : "";
+
+      // Replace placeholders
+      instructions = customTemplate
+        .replace(/{maxLength}/g, String(maxLength))
+        .replace(/{bodyInstructions}/g, bodyInstructions)
+        .replace(/{locale}/g, "en") // Could be made configurable if needed
+        .replace(/{diff}/g, ""); // We append diff separately
+
+      // Add custom instructions if provided (unless already in template)
+      if (customInstructions && !customTemplate.includes(customInstructions)) {
+        instructions += `\n\nADDITIONAL INSTRUCTIONS:\n${customInstructions}`;
+      }
+    } else if (commitType === "gitmoji") {
+      instructions = `You are an expert Git commit message generator that uses Gitmoji (emoji-based commits).
+
+Analyze the provided git diff and generate a commit message following the Gitmoji specification:
+
+FORMAT: <emoji> <type>[optional scope]: <description>
+
+Common Gitmoji mappings:
+- ✨ :sparkles: - New feature (feat)
+- 🐛 :bug: - Bug fix (fix)
+- 📝 :memo: - Documentation (docs)
+- 💄 :lipstick: - UI/styling (style)
+- ♻️ :recycle: - Code refactoring (refactor)
+- ⚡️ :zap: - Performance improvement (perf)
+- ✅ :white_check_mark: - Tests (test)
+- 🔧 :wrench: - Configuration (chore)
+- 🔨 :hammer: - Build/tooling (build)
+- 🚀 :rocket: - Deployment (ci)
+
+REQUIREMENTS:
+1. Subject line must NOT exceed ${maxLength} characters
+2. Use imperative mood (e.g., "add" not "added")
+3. Do not end subject with a period
+4. Start with the appropriate emoji${
+        includeBody
+          ? "\n5. Include a body section with 2-4 bullet points explaining key changes"
+          : ""
+      }
+
+${customInstructions ? `\nADDITIONAL INSTRUCTIONS:\n${customInstructions}\n` : ""}
+
+Return ONLY the commit message, no explanations or surrounding text.`;
+    } else {
+      // Conventional Commits format
+      instructions = `You are an expert Git commit message generator following Conventional Commits specification.
+
+Analyze the provided git diff and generate a commit message following this format:
+
+<type>[optional scope]: <description>
+${includeBody ? "\n[optional body]\n" : ""}
+[optional footer(s)]
+
+COMMIT TYPES:
+- feat: A new feature
+- fix: A bug fix
+- docs: Documentation only changes
+- style: Changes that don't affect code meaning (formatting, missing semicolons, etc.)
+- refactor: Code change that neither fixes a bug nor adds a feature
+- perf: Code change that improves performance
+- test: Adding missing tests or correcting existing tests
+- build: Changes to build system or external dependencies
+- ci: Changes to CI configuration files and scripts
+- chore: Other changes that don't modify src or test files
+- revert: Reverts a previous commit
+
+REQUIREMENTS:
+1. Subject line must NOT exceed ${maxLength} characters
+2. Use imperative mood (e.g., "add" not "added")
+3. Do not capitalize first letter after type
+4. Do not end subject with a period
+5. Choose the most specific scope when applicable (e.g., "auth", "api", "ui")${
+        includeBody
+          ? "\n6. Include a body section with 2-4 bullet points explaining:\n   - What changed\n   - Why it changed\n   - Any important implementation details"
+          : ""
+      }
+
+${customInstructions ? `\nADDITIONAL INSTRUCTIONS:\n${customInstructions}\n` : ""}
+
+Return ONLY the commit message, no explanations or surrounding text.`;
     }
-    
-    const response = await this.getFromVsCodeLlm(
-      instructions,
-      code,
-      progress
-    );
-    
-    if (response) {
-      let message = response.trim();
-      message = message.replace(/^"/gm, "");
-      message = message.replace(/"$/gm, "");
-      return message;
+
+    try {
+      const response = await this.getFromVsCodeLlm(instructions, code, progress);
+
+      if (response) {
+        let message = response.trim();
+        message = message.replace(/^"/gm, "");
+        message = message.replace(/"$/gm, "");
+        return message;
+      }
+      return null;
+    } catch (error) {
+      // Re-throw the error so it can be caught by the calling function
+      throw error;
     }
-    return null;
   }
 
   /**
@@ -67,23 +160,25 @@ class VsCodeLlmService implements AIService {
    * @param {string} string2 - the second parameter (diff code)
    * @returns The explanation of the git diff.
    */
-  async getExplainedChanges(
-    string1: string,
-    string2: string
-  ): Promise<string | null> {
+  async getExplainedChanges(_string1: string, string2: string): Promise<string | null> {
     const instructions =
       "You are a bot that explains the changes from the result of 'git diff --cached' that user given. commit message should be a multiple lines where first line doesn't exceed '50' characters by following commit message guidelines based on the given git diff changes without mentioning itself";
-    
+
     // Use string2 as the code/diff, string1 is typically instructions but we use our own
-    const response = await this.getFromVsCodeLlm(instructions, string2);
-    
-    if (response) {
-      let message = response.trim();
-      message = message.replace(/^"/gm, "");
-      message = message.replace(/"$/gm, "");
-      return message;
+    try {
+      const response = await this.getFromVsCodeLlm(instructions, string2);
+
+      if (response) {
+        let message = response.trim();
+        message = message.replace(/^"/gm, "");
+        message = message.replace(/"$/gm, "");
+        return message;
+      }
+      return null;
+    } catch (error) {
+      // Re-throw the error so it can be caught by the calling function
+      throw error;
     }
-    return null;
   }
 
   /**
@@ -99,10 +194,10 @@ class VsCodeLlmService implements AIService {
     progress?: vscode.Progress<{
       message?: string | undefined;
       increment?: number | undefined;
-    }>
+    }>,
   ): Promise<string | undefined> {
     const vscodeLmModel = WorkspaceService.getInstance().getVsCodeLmModel();
-    
+
     // Check cache
     const cacheKey = instructions + prompt;
     const exist = this.cacheService.recordExists(vscodeLmModel, cacheKey);
@@ -120,27 +215,149 @@ class VsCodeLlmService implements AIService {
 
       // Select the appropriate model based on settings
       let models: vscode.LanguageModelChat[] = [];
-      
-      if (vscodeLmModel === "copilot-gpt-4o") {
+
+      if (vscodeLmModel === "auto") {
+        // Try to select the best available model in order of preference
+        const preferredFamilies = [
+          "gpt-4o",
+          "o1",
+          "gpt-4",
+          "gpt-4-turbo",
+          "o1-mini",
+          "gpt-3.5-turbo",
+          "o1-preview",
+          "gpt-3.5",
+        ];
+        for (const family of preferredFamilies) {
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: family,
+          });
+          if (models.length > 0) {
+            break;
+          }
+        }
+        // If no specific family models found, try any copilot model
+        if (models.length === 0) {
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-gpt-4o") {
         models = await vscode.lm.selectChatModels({
           vendor: "copilot",
-          family: "gpt-4o"
+          family: "gpt-4o",
         });
+        if (models.length === 0) {
+          // Fallback to any GPT-4 model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: "gpt-4",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-gpt-4") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "gpt-4",
+        });
+        if (models.length === 0) {
+          // Fallback to any available copilot model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-gpt-4-turbo") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "gpt-4-turbo",
+        });
+        if (models.length === 0) {
+          // Fallback to any GPT-4 model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: "gpt-4",
+          });
+        }
       } else if (vscodeLmModel === "copilot-gpt-3.5-turbo") {
         models = await vscode.lm.selectChatModels({
           vendor: "copilot",
-          family: "gpt-3.5-turbo"
+          family: "gpt-3.5-turbo",
         });
+        if (models.length === 0) {
+          // Fallback to any GPT-3.5 model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: "gpt-3.5",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-gpt-3.5") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "gpt-3.5",
+        });
+        if (models.length === 0) {
+          // Fallback to any available copilot model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-o1") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "o1",
+        });
+        if (models.length === 0) {
+          // Fallback to any available copilot model
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-o1-mini") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "o1-mini",
+        });
+        if (models.length === 0) {
+          // Fallback to o1
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: "o1",
+          });
+        }
+      } else if (vscodeLmModel === "copilot-o1-preview") {
+        models = await vscode.lm.selectChatModels({
+          vendor: "copilot",
+          family: "o1-preview",
+        });
+        if (models.length === 0) {
+          // Fallback to o1
+          models = await vscode.lm.selectChatModels({
+            vendor: "copilot",
+            family: "o1",
+          });
+        }
       } else {
         // Default: try to select any copilot model
         models = await vscode.lm.selectChatModels({
-          vendor: "copilot"
+          vendor: "copilot",
         });
+
+        // If still no models available, show a more specific error
+        if (models.length === 0) {
+          window.showErrorMessage(
+            "No GitHub Copilot models available. Please ensure GitHub Copilot is installed, enabled, and you have an active subscription.",
+          );
+          progress?.report({
+            increment: 1,
+            message: "\nFailed - No Copilot models available.",
+          });
+          return undefined;
+        }
       }
 
       if (models.length === 0) {
         window.showErrorMessage(
-          "No language models available. Please ensure GitHub Copilot is installed and you are signed in."
+          "No language models available. Please ensure GitHub Copilot is installed and you are signed in.",
         );
         progress?.report({
           increment: 1,
@@ -154,17 +371,14 @@ class VsCodeLlmService implements AIService {
 
       progress?.report({ increment: 30 });
 
-      // Prepare messages
-      const messages = [
-        vscode.LanguageModelChatMessage.User(instructions),
-        vscode.LanguageModelChatMessage.User(prompt),
-      ];
+      // Prepare messages - try a simpler format that should be more compatible
+      const messages = [vscode.LanguageModelChatMessage.User(`${instructions}\n\n${prompt}`)];
 
-      // Send request
+      // Send request with minimal options
       const chatResponse = await model.sendRequest(
         messages,
         {},
-        new vscode.CancellationTokenSource().token
+        new vscode.CancellationTokenSource().token,
       );
 
       progress?.report({ increment: 40 });
@@ -190,20 +404,21 @@ class VsCodeLlmService implements AIService {
       await new Promise((f) => setTimeout(f, 200));
 
       return responseText;
-    } catch (error: any) {
+    } catch (error: unknown) {
       console.error(error);
       sendToOutput(`result failed: ${JSON.stringify(error)}`);
 
       if (error instanceof vscode.LanguageModelError) {
         // Handle specific LLM errors
         let errorMessage = "VS Code Language Model Error: ";
-        
+
         switch (error.code) {
           case vscode.LanguageModelError.NotFound().code:
             errorMessage += "Model not found. Please ensure GitHub Copilot is installed.";
             break;
           case vscode.LanguageModelError.NoPermissions().code:
-            errorMessage += "No permissions to use the language model. Please sign in to GitHub Copilot.";
+            errorMessage +=
+              "No permissions to use the language model. Please sign in to GitHub Copilot.";
             break;
           case vscode.LanguageModelError.Blocked().code:
             errorMessage += "Request was blocked. The prompt may violate content policies.";
@@ -211,12 +426,51 @@ class VsCodeLlmService implements AIService {
           default:
             errorMessage += error.message;
         }
-        
+
         window.showErrorMessage(errorMessage);
+      } else if (error instanceof Error) {
+        // Handle the specific "model_not_supported" error
+        let isModelNotSupported = false;
+        let actualErrorMessage = error.message;
+
+        // Check for model_not_supported in the error message
+        if (
+          error.message.includes("model_not_supported") ||
+          error.message.includes("Model is not supported")
+        ) {
+          isModelNotSupported = true;
+        } else {
+          // Try to parse the error message as JSON to check for nested error details
+          try {
+            // Extract JSON part from the error message if it exists
+            const jsonMatch = error.message.match(/\{.*\}/);
+            if (jsonMatch) {
+              const errorJson = JSON.parse(jsonMatch[0]);
+              if (errorJson.error && errorJson.error.code === "model_not_supported") {
+                isModelNotSupported = true;
+                // Use the actual error message from the LLM
+                if (errorJson.error.message) {
+                  actualErrorMessage = errorJson.error.message;
+                }
+              }
+            }
+          } catch (parseError) {
+            // If parsing fails, continue with normal error handling
+            console.error("Failed to parse error JSON:", parseError);
+          }
+        }
+
+        if (isModelNotSupported) {
+          window.showErrorMessage(
+            `Diffy Error: The selected language model doesn't support this type of request. Try switching to a different model in settings or use OpenAI instead. LLM Error: ${actualErrorMessage}`,
+          );
+        } else {
+          window.showErrorMessage(
+            `Diffy Error: Failed to generate commit message. ${error.message}`,
+          );
+        }
       } else {
-        window.showErrorMessage(
-          `Diffy Error: Failed to generate commit message. ${error.message || "Unknown error"}`
-        );
+        window.showErrorMessage("Diffy Error: Failed to generate commit message. Unknown error");
       }
 
       progress?.report({
diff --git a/src/service/WindowService.ts b/src/service/WindowService.ts
index 644530c..f92171c 100644
--- a/src/service/WindowService.ts
+++ b/src/service/WindowService.ts
@@ -1,4 +1,4 @@
-import { ViewColumn, WebviewPanel, window } from "vscode";
+import { ViewColumn, type WebviewPanel, window } from "vscode";
 
 export default class WindowService {
   static _instance: WindowService;
@@ -24,15 +24,10 @@ export default class WindowService {
   }
 
   private createWebviewPanel() {
-    this.panel = window.createWebviewPanel(
-      "ExplainGitDiff",
-      "Explain Git Diff",
-      ViewColumn.Two,
-      {
-        enableScripts: false,
-        retainContextWhenHidden: true,
-      }
-    );
+    this.panel = window.createWebviewPanel("ExplainGitDiff", "Explain Git Diff", ViewColumn.Two, {
+      enableScripts: false,
+      retainContextWhenHidden: true,
+    });
   }
 
   private getWebviewContent(explain: string) {
diff --git a/src/service/WorkspaceService.ts b/src/service/WorkspaceService.ts
index 4cf3c85..d6d3dcd 100644
--- a/src/service/WorkspaceService.ts
+++ b/src/service/WorkspaceService.ts
@@ -1,23 +1,20 @@
-import { EventEmitter } from "events";
-import { window, workspace, WorkspaceFolder } from "vscode";
+import { EventEmitter } from "node:events";
+import { type WorkspaceFolder, window, workspace } from "vscode";
 import { EventType } from "../@types/EventType";
 import { CONSTANTS } from "../Constants";
 
 export default class WorkspaceService extends EventEmitter {
   static _instance: WorkspaceService;
 
-  constructor() {
-    if (WorkspaceService._instance) {
-      return WorkspaceService._instance;
-    }
+  private constructor() {
     super();
     /* Listening for changes to the workspace configuration. */
-    workspace.onDidChangeConfiguration((e) => {
+    workspace.onDidChangeConfiguration((_e) => {
       this.emit(EventType.WORKSPACE_CHANGED);
     });
 
     /* Listening for changes to the workspace configuration. */
-    workspace.onDidChangeWorkspaceFolders((e) => {
+    workspace.onDidChangeWorkspaceFolders((_e) => {
       this.emit(EventType.WORKSPACE_CHANGED);
     });
   }
@@ -39,10 +36,7 @@ export default class WorkspaceService extends EventEmitter {
    * @returns A boolean value.
    */
   checkAndWarnWorkSpaceExist(): boolean {
-    if (
-      !workspace.workspaceFolders ||
-      workspace.workspaceFolders.length === 0
-    ) {
+    if (!workspace.workspaceFolders || workspace.workspaceFolders.length === 0) {
       this.showErrorMessage("Your are not in a Workspace");
       return false;
     }
@@ -55,10 +49,7 @@ export default class WorkspaceService extends EventEmitter {
    * @returns {string | null} The current workspace folder path.
    */
   getCurrentWorkspaceUri(): string | null {
-    if (
-      !workspace.workspaceFolders ||
-      workspace.workspaceFolders.length === 0
-    ) {
+    if (!workspace.workspaceFolders || workspace.workspaceFolders.length === 0) {
       return null;
     }
     return workspace.workspaceFolders[0].uri.fsPath;
@@ -69,10 +60,7 @@ export default class WorkspaceService extends EventEmitter {
    * @returns {WorkspaceFolder | null} The first workspace folder in the workspace.workspaceFolders array.
    */
   getCurrentWorkspace(): WorkspaceFolder | null {
-    if (
-      !workspace.workspaceFolders ||
-      workspace.workspaceFolders.length === 0
-    ) {
+    if (!workspace.workspaceFolders || workspace.workspaceFolders.length === 0) {
       return null;
     }
     return workspace.workspaceFolders[0];
@@ -90,11 +78,21 @@ export default class WorkspaceService extends EventEmitter {
     return workspace.getConfiguration(CONSTANTS.extensionName);
   }
 
+  getAiServiceProvider() {
+    const value = String(this.getConfiguration().get("aiServiceProvider"));
+    return value || "openai";
+  }
+
+  getVsCodeLmModel() {
+    const value = String(this.getConfiguration().get("vscodeLmModel"));
+    return value || "auto";
+  }
+
   getOpenAIKey() {
     const value = String(this.getConfiguration().get("openAiKey"));
     if (!value) {
       this.showErrorMessage(
-        "Your OpenAI API Key is missing; kindly input it within the Diffy Settings section. You can generate a key by visiting the OpenAI website."
+        "Your OpenAI API Key is missing; kindly input it within the Diffy Settings section. You can generate a key by visiting the OpenAI website.",
       );
       return null;
     }
@@ -119,7 +117,7 @@ export default class WorkspaceService extends EventEmitter {
       : undefined;
     if (!value) {
       this.showErrorMessage(
-        "Instructions for AI are absent; please provide them within the Diffy Settings section."
+        "Instructions for AI are absent; please provide them within the Diffy Settings section.",
       );
       return null;
     }
@@ -140,6 +138,59 @@ export default class WorkspaceService extends EventEmitter {
     return value;
   }
 
+  getCommitMessageType() {
+    const value = String(this.getConfiguration().get("commitMessageType"));
+    return value || "conventional";
+  }
+
+  getCustomCommitPrompt() {
+    const value = this.getConfiguration().get("customCommitPrompt");
+    if (typeof value === "string" && value.trim()) {
+      return value;
+    }
+    // Default custom template if not set
+    return `Generate a commit message for the following git diff.
+
+Requirements:
+- Maximum subject length: {maxLength} characters
+- Use imperative mood
+- Be concise and clear{bodyInstructions}
+
+Return ONLY the commit message, no explanations.`;
+  }
+
+  getIncludeCommitBody() {
+    const value = this.getConfiguration().get("includeCommitBody");
+    return value === true;
+  }
+
+  getExcludeFilesFromDiff(): string[] {
+    const value = this.getConfiguration().get("excludeFilesFromDiff");
+    if (Array.isArray(value)) {
+      return value;
+    }
+    // Default exclusions
+    return [
+      "package-lock.json",
+      "yarn.lock",
+      "pnpm-lock.yaml",
+      "*.jpg",
+      "*.png",
+      "*.gif",
+      "*.svg",
+      "*.ico",
+      "*.woff",
+      "*.woff2",
+      "*.ttf",
+      "*.eot",
+    ];
+  }
+
+  getMaxCommitMessageLength() {
+    const value = this.getConfiguration().get("maxCommitMessageLength");
+    return typeof value === "number" ? value : 72;
+  }
+
   /**
    * This function shows an error message
    * @param {string} msg - The message to display.
diff --git a/src/test/runTest.ts b/src/test/runTest.ts
index 27b3ceb..d569d87 100644
--- a/src/test/runTest.ts
+++ b/src/test/runTest.ts
@@ -1,23 +1,22 @@
-import * as path from 'path';
-
-import { runTests } from '@vscode/test-electron';
+import * as path from "node:path";
+import { runTests } from "@vscode/test-electron";
 
 async function main() {
-	try {
-		// The folder containing the Extension Manifest package.json
-		// Passed to `--extensionDevelopmentPath`
-		const extensionDevelopmentPath = path.resolve(__dirname, '../../');
+  try {
+    // The folder containing the Extension Manifest package.json
+    // Passed to `--extensionDevelopmentPath`
+    const extensionDevelopmentPath = path.resolve(__dirname, "../../");
 
-		// The path to test runner
-		// Passed to --extensionTestsPath
-		const extensionTestsPath = path.resolve(__dirname, './suite/index');
+    // The path to test runner
+    // Passed to --extensionTestsPath
+    const extensionTestsPath = path.resolve(__dirname, "./suite/index");
 
-		// Download VS Code, unzip it and run the integration test
-		await runTests({ extensionDevelopmentPath, extensionTestsPath });
-	} catch (err) {
-		console.error('Failed to run tests');
-		process.exit(1);
-	}
+    // Download VS Code, unzip it and run the integration test
+    await runTests({ extensionDevelopmentPath, extensionTestsPath });
+  } catch {
+    console.error("Failed to run tests");
+    process.exit(1);
+  }
 }
 
 main();
diff --git a/src/test/suite/extension.test.ts b/src/test/suite/extension.test.ts
index 4ca0ab4..ed67073 100644
--- a/src/test/suite/extension.test.ts
+++ b/src/test/suite/extension.test.ts
@@ -1,15 +1,16 @@
-import * as assert from 'assert';
+import * as assert from "node:assert";
 
 // You can import and use all API from the 'vscode' module
 // as well as import your extension to test it
-import * as vscode from 'vscode';
+import * as vscode from "vscode";
+
 // import * as myExtension from '../../extension';
 
-suite('Extension Test Suite', () => {
-	vscode.window.showInformationMessage('Start all tests.');
+suite("Extension Test Suite", () => {
+  vscode.window.showInformationMessage("Start all tests.");
 
-	test('Sample test', () => {
-		assert.strictEqual(-1, [1, 2, 3].indexOf(5));
-		assert.strictEqual(-1, [1, 2, 3].indexOf(0));
-	});
+  test("Sample test", () => {
+    assert.strictEqual(-1, [1, 2, 3].indexOf(5));
+    assert.strictEqual(-1, [1, 2, 3].indexOf(0));
+  });
 });
diff --git a/src/test/suite/index.ts b/src/test/suite/index.ts
index 7029e38..4f4a65e 100644
--- a/src/test/suite/index.ts
+++ b/src/test/suite/index.ts
@@ -1,38 +1,41 @@
-import * as path from 'path';
-import * as Mocha from 'mocha';
-import * as glob from 'glob';
+import * as path from "node:path";
+import { glob } from "glob";
+
+import Mocha = require("mocha");
 
 export function run(): Promise<void> {
-	// Create the mocha test
-	const mocha = new Mocha({
-		ui: 'tdd',
-		color: true
-	});
+  // Create the mocha test
+  const mocha = new Mocha({
+    ui: "tdd",
+    color: true,
+  });
 
-	const testsRoot = path.resolve(__dirname, '..');
+  const testsRoot = path.resolve(__dirname, "..");
 
-	return new Promise((c, e) => {
-		glob('**/**.test.js', { cwd: testsRoot }, (err, files) => {
-			if (err) {
-				return e(err);
-			}
+  return new Promise<void>((c, e) => {
+    glob("**/**.test.js", { cwd: testsRoot }, (err: Error | null, files: string[]) => {
+      if (err) {
+        return e(err);
+      }
 
-			// Add files to the test suite
-			files.forEach(f => mocha.addFile(path.resolve(testsRoot, f)));
+      // Add files to the test suite
+      files.forEach((f: string) => {
+        mocha.addFile(path.resolve(testsRoot, f));
+      });
 
-			try {
-				// Run the mocha test
-				mocha.run(failures => {
-					if (failures > 0) {
-						e(new Error(`${failures} tests failed.`));
-					} else {
-						c();
-					}
-				});
-			} catch (err) {
-				console.error(err);
-				e(err);
-			}
-		});
-	});
+      try {
+        // Run the mocha test
+        mocha.run((failures: number) => {
+          if (failures > 0) {
+            e(new Error(`${failures} tests failed.`));
+          } else {
+            c();
+          }
+        });
+      } catch (err) {
+        console.error(err);
+        e(err instanceof Error ? err : new Error(String(err)));
+      }
+    });
+  });
 }
diff --git a/tsconfig.json b/tsconfig.json
index 965a7b4..d2d3666 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,16 +1,15 @@
 {
-	"compilerOptions": {
-		"module": "commonjs",
-		"target": "ES2020",
-		"lib": [
-			"ES2020"
-		],
-		"sourceMap": true,
-		"rootDir": "src",
-		"strict": true   /* enable all strict type-checking options */
-		/* Additional Checks */
-		// "noImplicitReturns": true, /* Report error when not all code paths in function return a value. */
-		// "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */
-		// "noUnusedParameters": true,  /* Report errors on unused parameters. */
-	}
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "ES2020",
+    "lib": ["ES2020"],
+    "sourceMap": true,
+    "rootDir": "src",
+    "strict": true /* enable all strict type-checking options */,
+    /* Additional Checks */
+    "noImplicitReturns": true /* Report error when not all code paths in function return a value. */,
+    "useUnknownInCatchVariables": true /* Type caught variables as 'unknown' instead of 'any' */
+    // "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */
+    // "noUnusedParameters": true,  /* Report errors on unused parameters. */
+  }
 }
diff --git a/webpack.config.js b/webpack.config.js
index 37d7024..b9abb21 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -1,31 +1,29 @@
 //@ts-check
 
-'use strict';
-
-const path = require('path');
+const path = require("node:path");
 
 //@ts-check
 /** @typedef {import('webpack').Configuration} WebpackConfig **/
 
 /** @type WebpackConfig */
 const extensionConfig = {
-  target: 'node', // VS Code extensions run in a Node.js-context 📖 -> https://webpack.js.org/configuration/node/
-	mode: 'none', // this leaves the source code as close as possible to the original (when packaging we set this to 'production')
+  target: "node", // VS Code extensions run in a Node.js-context 📖 -> https://webpack.js.org/configuration/node/
+  mode: "none", // this leaves the source code as close as possible to the original (when packaging we set this to 'production')
 
-  entry: './src/extension.ts', // the entry point of this extension, 📖 -> https://webpack.js.org/configuration/entry-context/
+  entry: "./src/extension.ts", // the entry point of this extension, 📖 -> https://webpack.js.org/configuration/entry-context/
   output: {
     // the bundle is stored in the 'dist' folder (check package.json), 📖 -> https://webpack.js.org/configuration/output/
-    path: path.resolve(__dirname, 'dist'),
-    filename: 'extension.js',
-    libraryTarget: 'commonjs2'
+    path: path.resolve(__dirname, "dist"),
+    filename: "extension.js",
+    libraryTarget: "commonjs2",
   },
   externals: {
-    vscode: 'commonjs vscode' // the vscode-module is created on-the-fly and must be excluded. Add other modules that cannot be webpack'ed, 📖 -> https://webpack.js.org/configuration/externals/
+    vscode: "commonjs vscode", // the vscode-module is created on-the-fly and must be excluded. Add other modules that cannot be webpack'ed, 📖 -> https://webpack.js.org/configuration/externals/
     // modules added here also need to be added in the .vscodeignore file
   },
   resolve: {
     // support reading TypeScript and JavaScript files, 📖 -> https://github.com/TypeStrong/ts-loader
-    extensions: ['.ts', '.js']
+    extensions: [".ts", ".js"],
   },
   module: {
     rules: [
@@ -34,15 +32,15 @@ const extensionConfig = {
         exclude: /node_modules/,
         use: [
           {
-            loader: 'ts-loader'
-          }
-        ]
-      }
-    ]
+            loader: "ts-loader",
+          },
+        ],
+      },
+    ],
   },
-  devtool: 'nosources-source-map',
+  devtool: "nosources-source-map",
   infrastructureLogging: {
     level: "log", // enables logging required for problem matchers
   },
 };
-module.exports = [ extensionConfig ];
\ No newline at end of file
+module.exports = [extensionConfig];