name: Claude Code Review

permissions:
  contents: read
  pull-requests: write

on:
  pull_request:
    types: [opened, reopened, synchronize]
  workflow_dispatch:
    inputs:
      pr_number:
        description: 'Pull Request Number'
        required: true
        type: string

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

      - name: Get PR number
        id: pr-number
        run: |
          if [ "${{ github.event_name }}" = "workflow_dispatch" ]; then
            echo "number=${{ inputs.pr_number }}" >> $GITHUB_OUTPUT
          else
            echo "number=${{ github.event.pull_request.number }}" >> $GITHUB_OUTPUT
          fi

      - name: Get PR details
        id: pr-details
        uses: actions/github-script@v7
        with:
          script: |
            try {
              const { owner, repo } = context.repo;
              const prNumber = ${{ steps.pr-number.outputs.number }};
              
              console.log(`Getting PR #${prNumber} from ${owner}/${repo}`);
              
              const pr = await github.rest.pulls.get({
                owner: owner,
                repo: repo,
                pull_number: prNumber
              });
              
              return {
                base_sha: pr.data.base.sha,
                head_sha: pr.data.head.sha,
                base_ref: pr.data.base.ref,
                head_ref: pr.data.head.ref
              };
            } catch (error) {
              core.setFailed(`Failed to get PR details: ${error.message}`);
              throw error;
            }

      - name: Generate and analyze diff
        id: analysis
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
        run: |
          # Configure git to fetch PR refs
          git config --local --add remote.origin.fetch "+refs/pull/*/head:refs/remotes/origin/pr/*"
          git fetch origin
          
          BASE_SHA="${{ fromJSON(steps.pr-details.outputs.result).base_sha }}"
          HEAD_SHA="${{ fromJSON(steps.pr-details.outputs.result).head_sha }}"
          
          echo "Comparing $BASE_SHA..$HEAD_SHA"
          
          # Get the diff with context
          git diff -U10 "$BASE_SHA" "$HEAD_SHA" > diff_full.txt
          
          # Filter for relevant files
          cat diff_full.txt | \
            awk '/^diff --git/{p=0} /\.(js|ts|py|cpp|h|java|cs)$/{p=1} p' | \
            grep -v -E '^diff --git .*(package-lock\.json|yarn\.lock|\.md|\.json)' > diff_filtered.txt
          
          if [ ! -s diff_filtered.txt ]; then
            echo "No relevant changes found"
            echo "diff_size=0" >> $GITHUB_OUTPUT
            exit 0
          fi
          
          DIFF_SIZE=$(wc -c < diff_filtered.txt)
          echo "Found $DIFF_SIZE bytes of relevant changes"
          echo "diff_size=$DIFF_SIZE" >> $GITHUB_OUTPUT
          
          # Prepare the diff content for the API request
          DIFF_CONTENT=$(cat diff_filtered.txt)
          
          # Create the API request using a heredoc
          REQUEST=$(cat << EOF
          {
            "model": "claude-3-sonnet-20240229",
            "max_tokens": 4096,
            "temperature": 0.7,
            "messages": [{
              "role": "user",
              "content": "You are performing a code review. Please analyze this code diff and provide a thorough review that covers:\n\n1. Potential conflicts with existing codebase\n2. Code correctness and potential bugs\n3. Security vulnerabilities or risks\n4. Performance implications\n5. Maintainability and readability issues\n6. Adherence to best practices and coding standards\n7. Suggestions for improvements\n\nFor each issue found:\n- Explain the problem clearly\n- Rate the severity (Critical/High/Medium/Low)\n- Provide specific recommendations for fixes\n- Include code examples where helpful\n\nIf no issues are found in a particular area, explicitly state that.\n\nHere is the code diff to review:\n\n\`\`\`\n$DIFF_CONTENT\n\`\`\`"
            }]
          }
          EOF
          )
          
          # Make the API request
          echo "Sending request to Claude API..."
          RESPONSE=$(curl -s https://api.anthropic.com/v1/messages \
            -H "Content-Type: application/json" \
            -H "x-api-key: $ANTHROPIC_API_KEY" \
            -H "anthropic-version: 2023-06-01" \
            -d "$REQUEST")
          
          if echo "$RESPONSE" | jq -e '.content[0].text' > /dev/null; then
            # Save the review to a file to preserve formatting
            echo "$RESPONSE" | jq -r '.content[0].text' > review.txt
            echo 'review<<EOF' >> $GITHUB_OUTPUT
            cat review.txt >> $GITHUB_OUTPUT
            echo 'EOF' >> $GITHUB_OUTPUT
          else
            echo "Error in Claude API response: $RESPONSE"
            exit 1
          fi

      - name: Post review comment
        if: success() && steps.analysis.outputs.diff_size != '0'
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const { owner, repo } = context.repo;
            const review = `${{ steps.analysis.outputs.review }}`;
            const prNumber = ${{ steps.pr-number.outputs.number }};
            
            await github.rest.issues.createComment({
              owner,
              repo,
              issue_number: prNumber,
              body: `# Claude Code Review\n\n${review}`
            });