name: Commit Message Check

on:
  workflow_call:

jobs:
  commit-message:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout repository
        uses: actions/checkout@v6
        with:
          fetch-depth: 0

      - name: Validate commit messages
        run: |-
          BASE="${{ github.event.pull_request.base.sha }}"
          HEAD="${{ github.event.pull_request.head.sha }}"

          COMMITS=$(git log --format='%H %s' "${BASE}..$HEAD" --)

          if [ -z "$COMMITS" ]; then
            echo "No commits found in this PR."
            exit 0
          fi

          while IFS= read -r LINE; do
            SHA="${LINE%% *}"
            MSG="${LINE#* }"
            SHORT="${SHA::7}"

            if echo "$MSG" | grep -qP '^\[.+?\]'; then
              echo "✅ ${SHORT}: $MSG"
            else
              echo "❌ ${SHORT}: $MSG"
              echo "::error::Commit $SHORT is missing a [Tag] prefix. Expected format: [Tag] Description (e.g. [CPU] Fix overflow in JIT)"
              FAILED=1
            fi
          done <<< "${COMMITS}"

          echo

          if [ -n "$FAILED" ]; then
            echo "::error::One or more commits are missing a [Tag] prefix."
            echo
            echo "Expected format:  [Tag] Description"
            echo "Examples:         [CPU] <commit message>"
            echo "                  [GPU] <commit message>"
            echo "                  [UI] <commit message>"
            echo "                  [CI] <commit message>"
            exit 1
          fi

          echo "All commit messages have a valid [Tag] prefix."