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 diff and prepare review
        id: prepare
        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"
          
          # Create a temporary directory for our files
          mkdir -p /tmp/review
          
          # Get the full diff and store it
          git diff "$BASE_SHA" "$HEAD_SHA" > /tmp/review/changes.diff
          
          # Count total lines in diff
          TOTAL_LINES=$(wc -l < /tmp/review/changes.diff)
          echo "Total diff lines: $TOTAL_LINES"
          
          # Create filtered version
          cat /tmp/review/changes.diff | \
            grep -v -E '(package-lock.json|yarn.lock|node_modules|\.md$|\.json$)' | \
            grep -E '\.(js|ts|py|cpp|h|java|cs)$' > /tmp/review/filtered.diff || true
          
          if [ -s /tmp/review/filtered.diff ]; then
            DIFF_SIZE=$(wc -c < /tmp/review/filtered.diff)
            echo "Found $DIFF_SIZE bytes of relevant changes"
            echo "diff_size=$DIFF_SIZE" >> $GITHUB_OUTPUT
            
            # Base64 encode the diff to preserve newlines and special characters
            ENCODED_DIFF=$(base64 -w 0 /tmp/review/filtered.diff)
            echo "diff_content=$ENCODED_DIFF" >> $GITHUB_OUTPUT
            
            echo "Preview of changes:"
            head -n 5 /tmp/review/filtered.diff
          else
            echo "No relevant file changes found"
            echo "diff_size=0" >> $GITHUB_OUTPUT
          fi

      - name: Analyze code with Claude
        if: steps.prepare.outputs.diff_size != '0'
        id: analysis
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
        run: |
          # Decode the diff content
          echo "${{ steps.prepare.outputs.diff_content }}" | base64 -d > /tmp/review/decoded.diff
          DIFF_CONTENT=$(cat /tmp/review/decoded.diff)
          
          # Create request body
          REQUEST_BODY=$(jq -n \
            --arg content "You are performing a code review. Please analyze this code diff and provide a thorough review that covers:

          1. Potential conflicts with existing codebase
          2. Code correctness and potential bugs
          3. Security vulnerabilities or risks
          4. Performance implications
          5. Maintainability and readability issues
          6. Adherence to best practices and coding standards
          7. Suggestions for improvements

          For each issue found:
          - Explain the problem clearly
          - Rate the severity (Critical/High/Medium/Low)
          - Provide specific recommendations for fixes
          - Include code examples where helpful

          If no issues are found in a particular area, explicitly state that.

          Here is the code diff to review:

          \`\`\`
          $DIFF_CONTENT
          \`\`\`" \
            '{
              "model": "claude-3-sonnet-20240229",
              "max_tokens": 4096,
              "temperature": 0.7,
              "messages": [{
                "role": "user",
                "content": $content
              }]
            }')

          # 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_BODY")
          
          if echo "$RESPONSE" | jq -e '.content[0].text' > /dev/null; then
            # Base64 encode the review to preserve formatting
            REVIEW=$(echo "$RESPONSE" | jq -r '.content[0].text' | base64 -w 0)
            echo "review=$REVIEW" >> $GITHUB_OUTPUT
          else
            echo "Error in Claude API response: $RESPONSE"
            exit 1
          fi

      - name: Post review comment
        if: success() && steps.prepare.outputs.diff_size != '0'
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const { owner, repo } = context.repo;
            const review = Buffer.from('${{ steps.analysis.outputs.review }}', 'base64').toString();
            const prNumber = ${{ steps.pr-number.outputs.number }};
            
            await github.rest.issues.createComment({
              owner,
              repo,
              issue_number: prNumber,
              body: `# Claude Code Review\n\n${review}`
            });