deploy.yml

name: Deploy to GitHub Pages

on:
  push:
    branches: [master]

# Minimum permissions needed: write for Pages deployment, id-token for OIDC.
permissions:
  contents: write
  pages: write
  id-token: write

# Allow only one concurrent deployment. New pushes queue rather than
# cancelling a running deployment mid-flight.
concurrency:
  group: pages
  cancel-in-progress: false

jobs:

  # ---------------------------------------------------------------------------
  # Enumerate all v* semver tags so the matrix below can be generated
  # dynamically. Produces a JSON array like ["v1.0.0","v1.1.0"].
  # ---------------------------------------------------------------------------
  list-tags:
    runs-on: ubuntu-latest
    outputs:
      tags: ${{ steps.tags.outputs.list }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # full history is required to see all tags

      - name: Collect v* tags as a sorted JSON array
        id: tags
        # `git tag -l` may return nothing; `jq -s` always produces at least '[]'.
        # `sort -V` ensures natural version ordering (v1.9 < v1.10).
        run: |
          LIST=$(git tag -l 'v*' | sort -V | jq -R . | jq -s -c .)
          echo "list=$LIST" >> "$GITHUB_OUTPUT"

  # ---------------------------------------------------------------------------
  # Build the current master branch into the "latest" deployment slot.
  # ---------------------------------------------------------------------------
  build-latest:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # needed for git-based version stamps, if any

      - uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Build and stage latest
        shell: bash
        run: |
          set -euo pipefail

          npm run build

          # Guard: fail loudly if the build didn't produce the expected output.
          [[ -d dist/latest ]] || { echo "::error::dist/latest not found after build"; exit 1; }
          [[ -f dist/404.html ]] || { echo "::error::dist/404.html not found after build"; exit 1; }

          mkdir -p "deploy/sha"
          cp -r dist/latest "deploy/sha/${GITHUB_SHA}"
          cp dist/404.html deploy/404.html

      - uses: actions/upload-artifact@v4
        with:
          name: deploy-sha-${{ github.sha }}
          path: deploy/

  # ---------------------------------------------------------------------------
  # Build each tagged release into its own versioned deployment slot.
  # Each tag is cached so repeated deployments are cheap.
  # Skipped entirely when there are no v* tags.
  # ---------------------------------------------------------------------------
  build-tags:
    needs: list-tags
    if: needs.list-tags.outputs.tags != '[]'
    runs-on: ubuntu-latest
    strategy:
      matrix:
        tag: ${{ fromJSON(needs.list-tags.outputs.tags) }}
      fail-fast: false  # one bad tag should not block all others
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - name: Restore cached build for ${{ matrix.tag }}
        id: tag-cache
        uses: actions/cache@v4
        with:
          path: deploy/${{ matrix.tag }}
          key: tag-build-${{ matrix.tag }}

      # Only rebuild if the cache was cold. The cached directory is uploaded
      # as-is in the next step regardless.
      - name: Build ${{ matrix.tag }}
        if: steps.tag-cache.outputs.cache-hit != 'true'
        shell: bash
        run: |
          set -euo pipefail

          git checkout "${{ matrix.tag }}"

          # Re-install deps for this tag's lockfile (may differ from master).
          npm ci
          npm run build

          [[ -d dist/latest ]] || {
            echo "::error::dist/latest not found after building ${{ matrix.tag }}"
            exit 1
          }

          mkdir -p "deploy/${{ matrix.tag }}"
          rm -rf "deploy/${{ matrix.tag }}"
          cp -r dist/latest "deploy/${{ matrix.tag }}"

      - uses: actions/upload-artifact@v4
        with:
          name: deploy-${{ matrix.tag }}
          path: deploy/

  # ---------------------------------------------------------------------------
  # Merge all per-job artifacts and publish to GitHub Pages.
  # Runs even when build-tags was skipped (no tags exist yet);
  # fails only when build-latest itself failed.
  # ---------------------------------------------------------------------------
  deploy:
    needs: [build-latest, build-tags]
    if: always() && needs.build-latest.result == 'success'
    runs-on: ubuntu-latest
    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}
    steps:
      - uses: actions/checkout@v4

      # `merge-multiple: true` flattens all deploy-* artifacts directly into
      # `deploy/` without nesting, eliminating the need for a manual move loop.
      - name: Download and merge all build artifacts
        uses: actions/download-artifact@v4
        with:
          pattern: deploy-*
          path: deploy/
          merge-multiple: true

      - name: Cleanup old SHA builds (keep newest 10)
        env:
          SHA_KEEP_COUNT: 50
        shell: bash
        run: |
          if [[ -d deploy/sha ]]; then
            cd deploy/sha
            # List directories, sort (most recent = highest SHA first), skip the newest 10
            ls -1d */ 2>/dev/null \
              | sort -r \
              | tail -n +$((SHA_KEEP_COUNT + 1)) \
              | xargs -r rm -rf
            echo "Cleaned up old SHA builds"
          fi

      - name: Write latest/ redirect stub for backward compatibility
        shell: bash
        run: |
          mkdir -p deploy/latest
          cat > deploy/latest/index.html << 'STUB'
          <!DOCTYPE html>
          <html>
          <head><meta http-equiv="refresh" content="0;url=/"></head>
          <body><p>Redirecting to <a href="/">EdgeTTS Builds</a>...</p></body>
          </html>
          STUB

      - name: Generate version index page
        run: node scripts/generate-index.js deploy ${{ github.sha }}

      - uses: actions/configure-pages@v4

      - uses: actions/upload-pages-artifact@v3
        with:
          path: deploy/

      - name: Deploy to GitHub Pages
        id: deployment
        uses: actions/deploy-pages@v4