name: Traceability Validation

on:
  push:
    branches:
      - master
      - main
      - develop
  pull_request:
    branches:
      - master
      - main
      - develop

jobs:
  validate-traces:
    runs-on: linux/amd64
    name: Check Requirement Traces
    container:
      image: gitea.tourolle.paris/dtourolle/jellytau-builder:latest

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      # bun is baked into jellytau-builder (see Dockerfile.builder); no setup-bun
      # action needed — fetching it stalls on this Gitea runner.
      - name: Install dependencies
        run: bun install

      - name: Extract traces
        run: |
          echo "🔍 Extracting requirement traces..."
          bun run traces:json > traces-report.json

      - name: Validate traces
        run: |
          set -e

          echo "📊 Validating requirement traceability..."
          echo ""

          # Denominators come from docs/requirements.md at run time — NEVER
          # hardcode them here. This step previously divided by frozen literals
          # (UR/39, IR/24, DR/48, JA/3, total 114) while the file had grown to
          # 211 requirements, so it reported 158% coverage and the threshold
          # below could never trip. See docs/traceability-ci.md.
          TOTAL_TRACES=$(jq '.totalTraces' traces-report.json)
          COVERED=$(jq '.coverage.covered' traces-report.json)
          TOTAL_REQS=$(jq '.coverage.total' traces-report.json)
          COVERAGE=$(jq '.coverage.percent' traces-report.json)

          echo "✅ TRACES Found: $TOTAL_TRACES"
          echo ""
          echo "📋 Coverage Summary (traced / defined):"
          for T in UR IR DR JA; do
            TRACED=$(jq --arg t "$T" '[.byType[$t][] | select(. != null)] | length' traces-report.json)
            DEFINED=$(jq --arg t "$T" '.defined[$t]' traces-report.json)
            echo "   $T: $TRACED / $DEFINED"
          done
          echo ""

          echo "📈 Overall Coverage: $COVERED / $TOTAL_REQS ($COVERAGE%)"
          echo ""

          # Traced IDs that requirements.md does not define (typo, or a deleted
          # requirement). These do not count toward coverage.
          ORPHANED=$(jq -c '.coverage.orphaned' traces-report.json)
          if [ "$ORPHANED" != "[]" ]; then
            echo "⚠️  Traced but not defined in requirements.md: $ORPHANED"
            echo ""
          fi

          # A ratio above 100% means the computation is broken — the exact
          # condition that hid the stale-denominator bug. Fail loudly.
          if [ "$COVERAGE" -gt 100 ]; then
            echo "❌ ERROR: Coverage ($COVERAGE%) exceeds 100% — the gate is miscomputing."
            echo "   Orphaned IDs: $ORPHANED"
            exit 1
          fi

          # Minimum coverage. RATCHET POLICY: this number only ever goes UP.
          #
          # It sits a few points under the coverage actually achieved, so a real
          # regression trips it. It was 50 while true coverage was 86%, which
          # meant nearly half the matrix could rot before CI said a word — a
          # gate that cannot fail is not a gate.
          #
          # When coverage rises durably, raise this to just under the new figure
          # (`bun run traces:coverage` prints it). Never lower it to make a red
          # build pass — add the missing TRACES comments instead.
          #
          # Keep in sync with MIN_COVERAGE_PERCENT in scripts/extract-traces.ts;
          # scripts/extract-traces.test.ts fails if the two drift apart.
          MIN_THRESHOLD=88
          if [ "$COVERAGE" -lt "$MIN_THRESHOLD" ]; then
            echo "❌ ERROR: Coverage ($COVERAGE%) is below minimum threshold ($MIN_THRESHOLD%)"
            exit 1
          fi

          echo "✅ Coverage is acceptable ($COVERAGE% >= $MIN_THRESHOLD%)"

      # Every ID named by a TRACES comment must be defined as a table row in
      # docs/requirements.md. The extractor used to accept any well-formed ID
      # silently, so a typo or a rename that missed a call site passed CI
      # unnoticed (DR-189 and UT-188 lived in three source files, defined
      # nowhere, for months). This covers UT/IT too, which the coverage
      # orphan list above deliberately ignores.
      - name: Validate requirement IDs
        run: bun run traces:validate

      - name: Check modified files
        if: github.event_name == 'pull_request'
        run: |
          echo "🔍 Checking modified files for traces..."
          echo ""

          # Get changed files
          CHANGED=$(git diff --name-only origin/${{ github.base_ref }}...HEAD | grep -E '\.(ts|tsx|svelte|rs)$' || echo "")

          if [ -z "$CHANGED" ]; then
            echo "✅ No TypeScript/Rust files changed"
            exit 0
          fi

          echo "📝 Changed files:"
          echo "$CHANGED" | sed 's/^/   /'
          echo ""

          # Check each file
          # Pipe into the loop instead of a here-string (<<<) so this step works
          # under POSIX sh/dash, not just bash. Use `case` instead of `[[ == ]]`
          # for the same reason. The loop runs in a subshell (so a counter var
          # wouldn't survive), so we record warnings in a temp file and count it
          # afterwards.
          MISSING_FILE=$(mktemp)
          echo "$CHANGED" | while IFS= read -r file; do
            # Skip test files
            case "$file" in
              *.test.*) continue ;;
            esac

            if [ -f "$file" ]; then
              if ! grep -q "TRACES:" "$file"; then
                echo "⚠️  Missing TRACES: $file"
                echo "$file" >> "$MISSING_FILE"
              fi
            fi
          done

          MISSING_TRACES=$(wc -l < "$MISSING_FILE" | tr -d ' ')
          rm -f "$MISSING_FILE"

          if [ "$MISSING_TRACES" -gt 0 ]; then
            echo ""
            echo "📝 Recommendation: Add TRACES comments to new/modified code"
            echo "   Format: // TRACES: UR-001, UR-002 | DR-003"
            echo ""
            echo "💡 For more info, see: scripts/README.md"
          fi

      - name: Generate full report
        if: always()
        run: |
          echo "📄 Generating full traceability report..."
          bun run traces:markdown

      - name: Display report summary
        if: always()
        run: |
          echo ""
          echo "📊 Full Report Generated"
          echo "📁 Location: docs/traceability.md"
          echo ""
          head -50 docs/traceability.md || true

      - name: Save artifacts
        if: always()
        uses: actions/upload-artifact@v3
        with:
          name: traceability-reports
          path: |
            traces-report.json
            docs/traceability.md
          retention-days: 30