name: PR Checks
on:
  pull_request:
    types: [opened, edited, synchronize, reopened]

permissions:
  contents: read
  pull-requests: read

jobs:
  analyze:
    runs-on: ubuntu-latest
    outputs:
      should_run: ${{ steps.check-changes.outputs.should_run }}
      has_browser_tests: ${{ steps.check-coverage.outputs.has_browser_tests }}
      has_screen_recording: ${{ steps.check-recording.outputs.has_recording }}
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Ensure base branch is available
        run: |
          # Fetch the specific base commit to ensure it's available for git diff
          git fetch origin ${{ github.event.pull_request.base.sha }}

      - name: Check if significant changes exist
        id: check-changes
        run: |
          # Get list of changed files
          CHANGED_FILES=$(git diff --name-only ${{ github.event.pull_request.base.sha }}...${{ github.event.pull_request.head.sha }})
          
          # Filter for src/ files
          SRC_FILES=$(echo "$CHANGED_FILES" | grep '^src/' || true)
          
          if [ -z "$SRC_FILES" ]; then
            echo "No src/ files changed"
            echo "should_run=false" >> "$GITHUB_OUTPUT"
            exit 0
          fi
          
          # Count lines changed in src files
          TOTAL_LINES=0
          for file in $SRC_FILES; do
            if [ -f "$file" ]; then
              # Count added lines (non-empty)
              ADDED=$(git diff ${{ github.event.pull_request.base.sha }}...${{ github.event.pull_request.head.sha }} -- "$file" | grep '^+' | grep -v '^+++' | grep -v '^+$' | wc -l)
              # Count removed lines (non-empty)
              REMOVED=$(git diff ${{ github.event.pull_request.base.sha }}...${{ github.event.pull_request.head.sha }} -- "$file" | grep '^-' | grep -v '^---' | grep -v '^-$' | wc -l)
              TOTAL_LINES=$((TOTAL_LINES + ADDED + REMOVED))
            fi
          done
          
          echo "Total lines changed in src/: $TOTAL_LINES"
          
          if [ $TOTAL_LINES -gt 3 ]; then
            echo "should_run=true" >> "$GITHUB_OUTPUT"
          else
            echo "should_run=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Check browser test coverage
        id: check-coverage
        if: steps.check-changes.outputs.should_run == 'true'
        run: |
          # Check if browser tests were updated
          BROWSER_TEST_CHANGES=$(git diff --name-only ${{ github.event.pull_request.base.sha }}...${{ github.event.pull_request.head.sha }} | grep '^browser_tests/.*\.ts$' || true)
          
          if [ -n "$BROWSER_TEST_CHANGES" ]; then
            echo "has_browser_tests=true" >> "$GITHUB_OUTPUT"
          else
            echo "has_browser_tests=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Check for screen recording
        id: check-recording
        if: steps.check-changes.outputs.should_run == 'true'
        env:
          PR_BODY: ${{ github.event.pull_request.body }}
        run: |
          # Check PR body for screen recording
          # Check for GitHub user attachments or YouTube links
          if echo "$PR_BODY" | grep -qiE 'github\.com/user-attachments/assets/[a-f0-9-]+|youtube\.com/watch|youtu\.be/'; then
            echo "has_recording=true" >> "$GITHUB_OUTPUT"
          else
            echo "has_recording=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Final check and create results
        id: final-check
        if: always()
        run: |
          # Initialize results
          WARNINGS_JSON=""
          
          # Only run checks if should_run is true
          if [ "${{ steps.check-changes.outputs.should_run }}" == "true" ]; then
            # Check browser test coverage
            if [ "${{ steps.check-coverage.outputs.has_browser_tests }}" != "true" ]; then
              if [ -n "$WARNINGS_JSON" ]; then
                WARNINGS_JSON="${WARNINGS_JSON},"
              fi
              WARNINGS_JSON="${WARNINGS_JSON}{\"message\":\"⚠️ **Warning: E2E Test Coverage Missing**\\n\\nIf this PR modifies behavior that can be covered by browser-based E2E tests, those tests are required. PRs lacking applicable test coverage may not be reviewed until added. Please add or update browser tests to ensure code quality and prevent regressions.\"}"
            fi
            
            # Check screen recording
            if [ "${{ steps.check-recording.outputs.has_recording }}" != "true" ]; then
              if [ -n "$WARNINGS_JSON" ]; then
                WARNINGS_JSON="${WARNINGS_JSON},"
              fi
              WARNINGS_JSON="${WARNINGS_JSON}{\"message\":\"⚠️ **Warning: Visual Documentation Missing**\\n\\nIf this PR changes user-facing behavior, visual proof (screen recording or screenshot) is required. PRs without applicable visual documentation may not be reviewed until provided.\\nYou can add it by:\\n\\n- GitHub: Drag & drop media directly into the PR description\\n\\n- YouTube: Include a link to a short demo\"}"
            fi
          fi
          
          # Create results JSON
          if [ -n "$WARNINGS_JSON" ]; then
            # Create JSON with warnings
            cat > pr-check-results.json << EOF
          {
            "fails": [],
            "warnings": [$WARNINGS_JSON],
            "messages": [],
            "markdowns": []
          }
          EOF
            echo "failed=false" >> "$GITHUB_OUTPUT"
          else
            # Create JSON with success
            cat > pr-check-results.json << 'EOF'
          {
            "fails": [],
            "warnings": [],
            "messages": [],
            "markdowns": []
          }
          EOF
            echo "failed=false" >> "$GITHUB_OUTPUT"
          fi
          
          # Write PR metadata
          echo "${{ github.event.pull_request.number }}" > pr-number.txt
          echo "${{ github.event.pull_request.head.sha }}" > pr-sha.txt

      - name: Upload results
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: pr-check-results-${{ github.run_id }}
          path: |
            pr-check-results.json
            pr-number.txt
            pr-sha.txt
          retention-days: 1