# .github/workflows/demo-freeze-hotfix-validate.yml
# HOTFIX VALIDATION — the only permitted write path during the demo freeze.
# Author: Yachay <yachay@szlholdings.dev>  ·  ADDITIVE  ·  Doctrine v11 LOCKED (749/14/163)
# Signed-off-by: Yachay <yachay@szlholdings.dev>  (DCO)
# cosign keyid: szlholdings-cosign
#
# A hotfix PR is valid ONLY if ALL of the following hold:
#   1. Head branch matches  hotfix/*
#   2. PR contains exactly ONE commit (single-commit discipline)
#   3. The commit message contains the literal tag  [demo-hotfix]
#   4. The commit message references an issue  (#<n>  or  closes #<n>  etc.)
#   5. The commit is DCO-signed  (Signed-off-by: trailer present)
# Outside the freeze window this job runs but only WARNS (advisory), so normal
# multi-commit PRs are never blocked pre-freeze. ADDITIVE — no existing flow changes.

name: demo-freeze-hotfix-validate

on:
  pull_request:
    branches:
      - main
      - master

permissions:
  contents: read
  pull-requests: read

jobs:
  hotfix-validate:
    name: hotfix-validate
    runs-on: ubuntu-latest
    steps:
      - name: Checkout (full history for commit inspection)
        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
        with:
          fetch-depth: 0

      - name: Validate hotfix discipline
        shell: bash
        env:
          FREEZE_START: '2026-06-09'
          FREEZE_END: '2026-06-20'
          BRANCH: ${{ github.head_ref }}
          BASE_SHA: ${{ github.event.pull_request.base.sha }}
          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          set -euo pipefail
          TODAY="$(date -u +%Y-%m-%d)"

          in_window=0
          if [[ "${TODAY}" > "${FREEZE_START}" || "${TODAY}" == "${FREEZE_START}" ]] && \
             [[ "${TODAY}" < "${FREEZE_END}"   || "${TODAY}" == "${FREEZE_END}"   ]]; then
            in_window=1
          fi

          # Only enforce on hotfix/* branches; other branches handled by demo-freeze.yml.
          case "${BRANCH}" in
            hotfix/*) : ;;
            *)
              echo "ℹ️  Branch '${BRANCH}' is not hotfix/* — hotfix-validate skips (demo-freeze.yml owns gating)."
              exit 0
              ;;
          esac

          fail() {
            if [ "${in_window}" -eq 1 ]; then
              echo "::error title=Invalid hotfix::$1"
              FAILED=1
            else
              echo "::warning title=Hotfix advisory (pre-freeze)::$1"
            fi
          }
          FAILED=0

          # ---- collect the PR commit range ----
          RANGE="${BASE_SHA}..${HEAD_SHA}"
          mapfile -t SHAS < <(git rev-list "${RANGE}")
          N="${#SHAS[@]}"
          echo "::group::hotfix commits (${N}) on ${BRANCH}"
          git log --oneline "${RANGE}" || true
          echo "::endgroup::"

          # 2. single-commit discipline
          if [ "${N}" -ne 1 ]; then
            fail "Hotfix PR must be a SINGLE commit; found ${N}. Squash to one signed commit."
          fi

          # Inspect the head commit message + body + trailers
          MSG="$(git log -1 --format='%B' "${HEAD_SHA}")"

          # 3. [demo-hotfix] tag
          if ! grep -qF '[demo-hotfix]' <<<"${MSG}"; then
            fail "Commit message must contain the literal tag [demo-hotfix]."
          fi

          # 4. issue reference (#123, GH-123, closes/fixes #123, or org/repo#123)
          if ! grep -qiE '(\b(close[sd]?|fix(e[sd])?|resolve[sd]?)\b[[:space:]]+)?(#|GH-)[0-9]+' <<<"${MSG}"; then
            fail "Commit message must reference an issue (e.g. '#123' or 'fixes #123')."
          fi

          # 5. DCO sign-off
          if ! git log -1 --format='%B' "${HEAD_SHA}" | grep -qiE '^Signed-off-by: .+ <.+@.+>'; then
            fail "Commit must be DCO-signed (git commit -s) — 'Signed-off-by:' trailer required."
          fi

          if [ "${FAILED}" -eq 1 ]; then
            echo ""
            echo "════════════════════════════════════════════════════════════"
            echo " ❌ Hotfix rejected — fix the items above and force-push one"
            echo "    squashed, signed commit. Doctrine v11 LOCKED (749/14/163)."
            echo "    Sign: Yachay <yachay@szlholdings.dev>"
            echo "════════════════════════════════════════════════════════════"
            exit 1
          fi
          echo "✅ Hotfix discipline satisfied: single signed commit, [demo-hotfix], issue ref, DCO."