name: Check APK compatible version/release

on:
  pull_request_target:
    types: [opened, synchronize, converted_to_draft, ready_for_review, edited]

jobs:
  build:
    name: Check APK compatible version/release
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false

    permissions:
      pull-requests: write

    steps:
      - uses: actions/checkout@v4
        with:
          ref: ${{ github.event.pull_request.head.sha }}
          fetch-depth: 0

      - name: Determine branch name
        run: |
          BRANCH="${GITHUB_BASE_REF#refs/heads/}"
          echo "Building for $BRANCH"
          echo "BRANCH=$BRANCH" >> $GITHUB_ENV

      - name: Setup APK
        run: |
          wget -O $GITHUB_WORKSPACE/apk https://buildbot.aparcar.org/apk.static
          chmod +x $GITHUB_WORKSPACE/apk

      - name: Determine changed packages
        run: |
          RET=0
          INCOMPATIBLE_VERSION=""

          # only detect packages with changes
          PKG_ROOTS=$(find . -name Makefile | \
            grep -v ".*/src/Makefile" | \
            sed -e 's@./\(.*\)/Makefile@\1/@')
          CHANGES=$(git diff --diff-filter=d --name-only origin/$BRANCH...)

          for ROOT in $PKG_ROOTS; do
            for CHANGE in $CHANGES; do
              if [[ "$CHANGE" == "$ROOT"* ]]; then
                PKG_RELEASE=$(grep -E '^PKG_RELEASE' "$ROOT/Makefile" | cut -f 2 -d '=')
                if [ -n "$PKG_RELEASE" ]; then
                  if [[ "$PKG_RELEASE" == '^[0-9]+$' ]]; then
                    echo "PKG_RELEASE is not an integer: $PKG_RELEASE"
                    INCOMPATIBLE_VERSION+=" $ROOT"
                    break
                  fi
                fi
                PKG_VERSION=$(grep -E '^PKG_VERSION' "$ROOT/Makefile" | cut -f 2 -d '=')
                if [ -n "$PKG_VERSION" ]; then
                  $GITHUB_WORKSPACE/apk version --quiet --check "$PKG_VERSION"
                  if [[ "$?" -gt "0" ]]; then
                    echo "PKG_VERSION is not compatible: $PKG_VERSION"
                    INCOMPATIBLE_VERSION+=" $ROOT"
                  fi
                fi
              fi
            done
          done

          echo "Incompatible versions: $INCOMPATIBLE_VERSION"

          if [ -n "$INCOMPATIBLE_VERSION" ]; then
            RET=1
            cat > "$GITHUB_WORKSPACE/pr_comment.md" << EOF
          OpenWrt will change to the APK package manager which requires
          deterministic verisons. Please make sure that **PKG_VERSION**
          follows [Semantic Versioning](https://semver.org) or more specifically,
          the [APK version scheme](https://gitlab.alpinelinux.org/alpine/apk-tools/-/blob/master/doc/apk-package.5.scd?ref_type=heads#L47).
          If the version is based on a date, please use dots instead of dashes, i.e. **24.01.01**.

          The **PKG_RELEASE** should be an integer and not contain any letters or special characters.

          EOF

          fi

          for ROOT in $INCOMPATIBLE_VERSION; do
            echo "  - ${ROOT}Makefile" >> "$GITHUB_WORKSPACE/pr_comment.md"
          done

          exit $RET

      - name: Find Comment
        uses: peter-evans/find-comment@v2
        if: ${{ failure() }}
        id: fc
        with:
          issue-number: ${{ github.event.pull_request.number }}
          comment-author: "github-actions[bot]"

      - name: Create or update comment
        uses: peter-evans/create-or-update-comment@v2
        if: ${{ failure() }}
        with:
          comment-id: ${{ steps.fc.outputs.comment-id }}
          issue-number: ${{ github.event.pull_request.number }}
          body-file: "pr_comment.md"
          edit-mode: replace