name: Build and Release

on:
  pull_request:
    branches:
      - main
  push:
    branches:
      - main
    tags:
      - 'v*'
  workflow_dispatch:

concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

permissions:
  contents: write

jobs:
  build:
    name: Build executables
    runs-on: ubuntu-latest
    env:
      ZIG_INSTALL_ROOT: /ci-cache/zig-chess/0.16.0/linux-amd64/tool
      ZIG_LOCAL_CACHE_DIR: /ci-cache/zig-chess/0.16.0/linux-amd64/local
      ZIG_GLOBAL_CACHE_DIR: /ci-cache/zig-chess/0.16.0/linux-amd64/global

    steps:
      - name: Checkout
        uses: https://github.com/actions/checkout@v4

      - name: Install pinned Zig from the persistent cache
        run: |
          set -eu
          cache_parent="$(dirname "$ZIG_INSTALL_ROOT")"
          mkdir -p "$cache_parent"
          exec 9>"$cache_parent/.install.lock"
          flock -x 9
          if ! test -x "$ZIG_INSTALL_ROOT/zig" || \
             ! test "$("$ZIG_INSTALL_ROOT/zig" version)" = "0.16.0"; then
            archive="$(mktemp /tmp/zig-0.16.0.XXXXXXXX.tar.xz)"
            staging="$(mktemp -d "$cache_parent/.tool.XXXXXXXX")"
            trap 'rm -f "$archive"; rm -rf "$staging"' EXIT
            curl --fail --location --retry 3 --retry-all-errors \
              --output "$archive" \
              https://ziglang.org/download/0.16.0/zig-x86_64-linux-0.16.0.tar.xz
            printf '%s  %s\n' \
              70e49664a74374b48b51e6f3fdfbf437f6395d42509050588bd49abe52ba3d00 \
              "$archive" | sha256sum --check -
            tar -xJf "$archive" --strip-components=1 -C "$staging"
            rm -rf "$ZIG_INSTALL_ROOT"
            mv "$staging" "$ZIG_INSTALL_ROOT"
            rm -f "$archive"
            trap - EXIT
          fi
          echo "$ZIG_INSTALL_ROOT" >> "$GITHUB_PATH"

      - name: Install shader compiler
        run: |
          apt-get -o Acquire::Retries=2 update
          apt-get install -y --no-install-recommends glslc

      - name: Show tool versions
        run: |
          zig version
          glslc --version

      - name: Prepare persistent Zig caches
        run: |
          mkdir -p "$ZIG_LOCAL_CACHE_DIR" "$ZIG_GLOBAL_CACHE_DIR"

      - name: Build GUI executable
        run: |
          zig build \
            --cache-dir "$ZIG_LOCAL_CACHE_DIR" \
            --global-cache-dir "$ZIG_GLOBAL_CACHE_DIR"

      - name: Build magic generator executable
        run: |
          zig build magic-numbers \
            --cache-dir "$ZIG_LOCAL_CACHE_DIR" \
            --global-cache-dir "$ZIG_GLOBAL_CACHE_DIR"

      - name: Package executables
        run: |
          set -eu
          version="${GITHUB_REF_NAME}"
          os="$(uname -s | tr '[:upper:]' '[:lower:]')"
          arch="$(uname -m)"
          artifact_dir="zig-chess-${version}-${os}-${arch}"
          mkdir -p "dist/${artifact_dir}"
          cp zig-out/bin/zig-chess "dist/${artifact_dir}/"
          cp zig-out/bin/magic-numbers "dist/${artifact_dir}/"
          tar -C dist -czf "dist/${artifact_dir}.tar.gz" "${artifact_dir}"
          sha256sum "dist/${artifact_dir}.tar.gz" > "dist/${artifact_dir}.tar.gz.sha256"

      - name: Upload build artifact
        uses: https://github.com/actions/upload-artifact@v3
        with:
          name: zig-chess-${{ github.ref_name }}
          path: |
            dist/*.tar.gz
            dist/*.sha256

      - name: Create Gitea release for version tag
        if: startsWith(github.ref, 'refs/tags/v')
        env:
          GITEA_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -eu
          api="${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}"
          tag="${GITHUB_REF_NAME}"

          release_json="$(mktemp)"
          asset_response="$(mktemp)"

          printf '{"tag_name":"%s","target_commitish":"%s","name":"%s","body":"Automated release for %s","draft":false,"prerelease":false}' \
            "$tag" "$GITHUB_SHA" "$tag" "$tag" > "$release_json"

          response="$(curl -sS \
            -H "Authorization: token ${GITEA_TOKEN}" \
            -H "Content-Type: application/json" \
            -X POST \
            --data @"$release_json" \
            "${api}/releases")"

          release_id="$(printf '%s' "$response" | python3 -c 'import json,sys; print(json.load(sys.stdin)["id"])')"

          for asset in dist/*.tar.gz dist/*.sha256; do
            name="$(basename "$asset")"
            curl -sS \
              -H "Authorization: token ${GITEA_TOKEN}" \
              -X POST \
              -F "attachment=@${asset}" \
              "${api}/releases/${release_id}/assets?name=${name}" > "$asset_response"
          done