pr.yaml

name: PR

on:
  pull_request:

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: write
  packages: write

env:
  REGISTRY: ghcr.io
  IMAGE: ghcr.io/${{ github.repository }}
  FONT_NAME: afio

jobs:
  rc-checks:
    if: startsWith(github.head_ref, 'v') && endsWith(github.head_ref, '-rc')
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - name: Validate VERSION matches branch
        run: |
          VERSION=$(cat VERSION | tr -d '[:space:]')
          BRANCH="${{ github.head_ref }}"
          EXPECTED="v${VERSION}-rc"
          if [ "$BRANCH" != "$EXPECTED" ]; then
            echo "::error::VERSION file (${VERSION}) does not match branch ${BRANCH} (expected ${EXPECTED})"
            exit 1
          fi

      - name: Check release notes in PR description
        env:
          PR_BODY: ${{ github.event.pull_request.body }}
        run: |
          if [ -z "$PR_BODY" ]; then
            echo "::error::PR description is required for RC branches (used as release notes)"
            exit 1
          fi

  build-image:
    runs-on: ubuntu-latest
    outputs:
      image-ref: ${{ steps.refs.outputs.image_ref }}
      short-sha: ${{ steps.sha.outputs.short }}
    steps:
      - uses: actions/checkout@v6
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - uses: docker/setup-buildx-action@v4

      - uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - id: sha
        run: |
          SHA="${{ github.event.pull_request.head.sha }}"
          echo "short=${SHA::7}" >> "$GITHUB_OUTPUT"

      - id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.IMAGE }}
          tags: |
            type=raw,value=sha-${{ steps.sha.outputs.short }}

      - uses: docker/build-push-action@v7
        with:
          context: .
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          cache-from: type=gha
          cache-to: type=gha,mode=max

      - id: refs
        run: echo "image_ref=${{ env.IMAGE }}:sha-${{ steps.sha.outputs.short }}" >> "$GITHUB_OUTPUT"

  build-font:
    needs: build-image
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Restore verda cache
        uses: actions/cache@v5
        with:
          path: .verda-cache
          key: verda-${{ hashFiles('VERSION') }}-${{ hashFiles('private-build-plans.toml') }}
          restore-keys: |
            verda-${{ hashFiles('VERSION') }}-

      - name: Build font
        env:
          IMAGE_REF: ${{ needs.build-image.outputs.image-ref }}
          VERDA_CACHE: .verda-cache
        run: ./build.sh

      - uses: actions/upload-artifact@v7
        with:
          name: font-build
          path: _output/${{ env.FONT_NAME }}-*.zip

  visual-check:
    needs: build-font
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6

      - uses: actions/download-artifact@v8
        with:
          name: font-build
          path: _output

      - name: Extract fonts
        run: |
          mkdir -p _fonts
          unzip _output/${FONT_NAME}-*.zip -d _fonts/

      - name: Generate showcase PNGs
        run: python3 src/generate_showcase_matrix.py --font-dir _fonts --output-dir _generated

      - name: Install imagemagick
        run: sudo apt-get update -yqq && sudo apt-get install -yqq imagemagick

      - name: Pixel diff with reference
        run: |
          DIFF_FOUND=0
          mkdir -p _diffs
          for ref in docs/imgs/generated/*.png; do
            name=$(basename "$ref")
            gen="_generated/$name"
            if [ ! -f "$gen" ]; then
              echo "::error::Missing generated file: $name"
              DIFF_FOUND=1
              continue
            fi
            PIXELS=$(compare -metric AE "$ref" "$gen" "_diffs/$name" 2>&1 || true)
            if [ "$PIXELS" != "0" ]; then
              echo "::warning::$name: $PIXELS pixels differ"
              DIFF_FOUND=1
            else
              rm -f "_diffs/$name"
            fi
          done
          if [ "$DIFF_FOUND" -eq 1 ]; then
            echo "::error::Visual regression detected"
            exit 1
          fi

      - uses: actions/upload-artifact@v7
        if: failure()
        with:
          name: visual-diffs
          path: _diffs/

      - uses: actions/upload-artifact@v7
        if: failure()
        with:
          name: visual-generated
          path: _generated/*.png

  prerelease:
    if: startsWith(github.head_ref, 'v') && endsWith(github.head_ref, '-rc')
    needs: [rc-checks, visual-check]
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - name: Extract version
        run: |
          VERSION=$(cat VERSION | tr -d '[:space:]')
          echo "VERSION=${VERSION}" >> "$GITHUB_ENV"

      - name: Download font artifact
        uses: actions/download-artifact@v8
        with:
          name: font-build
          path: _output

      - name: Create pre-release
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          SHA: ${{ github.event.pull_request.head.sha }}
          PR_BODY: ${{ github.event.pull_request.body }}
        run: |
          RC_TAG="v${VERSION}-rc.${{ github.run_number }}"

          mv _output/${FONT_NAME}-*.zip "_output/${FONT_NAME}-${RC_TAG}.zip"

          gh api "repos/${{ github.repository }}/git/refs" \
            -f ref="refs/tags/${RC_TAG}" \
            -f sha="${SHA}"

          gh release create "$RC_TAG" \
            "_output/${FONT_NAME}-${RC_TAG}.zip" \
            -R "${{ github.repository }}" \
            --prerelease \
            --title "$RC_TAG" \
            --notes "$PR_BODY"