ai-code-review.yml

name: AI Code Review

on:
  pull_request:
    types: [opened, synchronize, reopened]
  workflow_dispatch:

permissions:
  pull-requests: write
  contents: read

jobs:
  code-review:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout PR code
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Get PR diff
        id: diff
        run: |
          git diff origin/${{ github.base_ref }}...HEAD > pr.diff
          MAX_SIZE=50000
          if [ $(wc -c < pr.diff) -gt $MAX_SIZE ]; then
            head -c $MAX_SIZE pr.diff > pr_truncated.diff
            mv pr_truncated.diff pr.diff
            echo "warning=Diff truncated to ${MAX_SIZE} bytes" >> $GITHUB_OUTPUT
          fi
          FILES_CHANGED=$(git diff --name-only origin/${{ github.base_ref }}...HEAD | wc -l)
          echo "files_changed=$FILES_CHANGED" >> $GITHUB_OUTPUT

      - name: Code Review
        id: review
        env:
          API_KEY: ${{ secrets.AI_PROVIDER_API_KEY }}
          API_ENDPOINT: ${{ secrets.AI_PROVIDER_API_ENDPOINT }}
          MODEL: ${{ secrets.AI_PROVIDER_MODEL }}
        run: |
          set +x  # Disable verbose mode to prevent secret leakage in logs
          DIFF=$(cat pr.diff | jq -Rs .)

          # Retry logic with exponential backoff
          MAX_RETRIES=3
          RETRY_COUNT=0
          HTTP_CODE=0

          while [ $RETRY_COUNT -lt $MAX_RETRIES ]; do
            HTTP_CODE=$(curl -s -o response.json -w "%{http_code}" $API_ENDPOINT \
              -H "Authorization: Bearer $API_KEY" \
              -H "Content-Type: application/json" \
              -H "Accept-Language: en-US,en" \
              -d "{
                \"model\": \"$MODEL\",
                \"messages\": [
                  {
                    \"role\": \"system\",
                    \"content\": \"You are an expert code reviewer. Analyze the PR diff and provide:\\n\\n1. **Summary**: Brief overview\\n2. **Issues**: Bugs or problems (if any)\\n3. **Security**: Security concerns (if any)\\n4. **Performance**: Performance considerations (if any)\\n5. **Best Practices**: Swift 6, concurrency, architecture (if any)\\n6. **Suggestions**: Optional improvements\\n\\nBe concise but thorough. Use markdown formatting.\"
                  },
                  {
                    \"role\": \"user\",
                    \"content\": ${DIFF}
                  }
                ],
                \"temperature\": 0.3,
                \"max_tokens\": 4096
              }")

            if [ "$HTTP_CODE" -eq 200 ]; then
              break
            fi

            RETRY_COUNT=$((RETRY_COUNT + 1))
            if [ $RETRY_COUNT -lt $MAX_RETRIES ]; then
              WAIT_TIME=$((2 ** RETRY_COUNT))
              echo "API returned $HTTP_CODE. Retrying in ${WAIT_TIME}s... (Attempt $RETRY_COUNT/$MAX_RETRIES)"
              sleep $WAIT_TIME
            fi
          done

          if [ "$HTTP_CODE" -ne 200 ]; then
            echo "Error: API returned $HTTP_CODE after $MAX_RETRIES attempts"
            cat response.json
            exit 1
          fi

          RESPONSE=$(cat response.json)
          REVIEW=$(echo "$RESPONSE" | jq -r '.choices[0].message.content')

          # Check if review was extracted successfully
          if [ -z "$REVIEW" ] || [ "$REVIEW" == "null" ]; then
            echo "Error: Failed to extract review content from API response"
            echo "Response: $RESPONSE"
            exit 1
          fi

          echo "$REVIEW" > review.md

          cat > review_with_header.md << EOF
          ### 🧠 AI Code Review

          $REVIEW
          EOF

          if [ -n "${{ steps.diff.outputs.warning }}" ]; then
            echo "" >> review_with_header.md
            echo "⚠️ **Note**: ${{ steps.diff.outputs.warning }}" >> review_with_header.md
          fi

      - name: Post review as PR comment
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            const review = fs.readFileSync('review_with_header.md', 'utf8');

            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
            });

            const botComment = comments.find(comment =>
              comment.user.type === 'Bot' &&
              comment.body.includes('AI Code Review')
            );

            if (botComment) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body: review
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body: review
              });
            }