# example:
#       - uses: ./.github/actions/get-llvm
#         with:
#           target: x86_64-unknown-linux-gnu

name: "Download LLVM"
inputs:
  target:
    required: true
  version:
    description: "LLVM release version (e.g., 'llvm-18.1.8'). If not specified, uses the latest published LLVM release. To test a specific draft release, use the full name (e.g. 'llvm-21.1.8-revive.0f80912')."
    required: false
    default: ""

runs:
  using: "composite"
  steps:
    - name: detect llvm version from submodule
      id: detect-version
      shell: bash
      run: |
        if [ -z "${{ inputs.version }}" ]; then
          # Get the full version from the LLVM submodule.
          git submodule update --init --recursive
          cd llvm
          # Try to get the most recent tag (e.g., "llvmorg-18.1.8")
          LLVM_TAG=$(git describe --tags --abbrev=0 2>/dev/null)
          if [ -n "$LLVM_TAG" ]; then
            echo "Detected LLVM version from submodule: $LLVM_TAG"
            # Convert "llvmorg-x.y.z" to "llvm-x.y.z"
            LLVM_VERSION=$(echo "$LLVM_TAG" | sed 's/^llvmorg-/llvm-/')
            echo "Detected LLVM version from submodule: $LLVM_VERSION"
            echo "version_prefix=$LLVM_VERSION" >> $GITHUB_OUTPUT
          else
            echo "Could not detect LLVM version from submodule, will use latest release"
            echo "version_prefix=" >> $GITHUB_OUTPUT
          fi
          cd ..
        else
          echo "Using explicitly provided version: ${{ inputs.version }}"
          echo "version_prefix=${{ inputs.version }}" >> $GITHUB_OUTPUT
        fi

    - name: find asset
      id: find
      uses: actions/github-script@v7
      env:
        target: ${{ inputs.target }}
        version_prefix: ${{ steps.detect-version.outputs.version_prefix }}
      with:
        result-encoding: string
        script: |
          let page = 1;
          let allReleases = [];

          let target = process.env.target
          let versionPrefix = process.env.version_prefix

          // Fetch all releases from all pages
          core.info('Fetching releases from revive repository...');
          let hasMorePages = true;
          while (hasMorePages) {
            const res = await github.rest.repos.listReleases({
              owner: context.repo.owner,
              repo: context.repo.repo,
              per_page: 50,
              page,
            });

            if (res.data.length > 0) {
              core.info(`Page ${page}: Fetched ${res.data.length} releases`);
              allReleases.push(...res.data);
              page++;
            } else {
              hasMorePages = false;
            }
          }

          core.info(`Total releases fetched: ${allReleases.length}`);

          // Sort all releases by publication date (newest first)
          allReleases.sort((a, b) => new Date(b.published_at) - new Date(a.published_at));

          // Debug: Print all LLVM releases
          const llvmReleases = allReleases.filter(r => r.tag_name.startsWith('llvm-') && !r.prerelease);
          core.info(`Found ${llvmReleases.length} LLVM releases in total:`);
          llvmReleases.forEach(r => {
            core.info(`  - ${r.tag_name} (published: ${r.published_at})`);
          });

          // Find the appropriate LLVM release
          let llvmRelease;
          if (versionPrefix) {
            // Search for latest release matching the version prefix
            llvmRelease = llvmReleases.find(release => {
              return release.tag_name.startsWith(versionPrefix);
            });
            if (llvmRelease) {
              core.info(`Selected LLVM release matching prefix '${versionPrefix}': ${llvmRelease.tag_name}`);
            }
          } else {
            // Find latest LLVM release (first in sorted list)
            llvmRelease = llvmReleases[0];
            if (llvmRelease) {
              core.info(`Selected latest LLVM version: ${llvmRelease.tag_name}`);
            }
          }

          if (llvmRelease) {
            let asset = llvmRelease.assets.find(asset => {
              return asset.name.includes(target);
            });
            if (!asset) {
              core.setFailed(`Artifact for '${target}' not found in release ${llvmRelease.tag_name} (${llvmRelease.html_url})`);
              process.exit();
            }
            // Use the API URL (rather than `browser_download_url`) so that
            // the authorization header is respected for draft releases.
            return asset.url;
          }

          if (versionPrefix) {
            core.setFailed(`No LLVM releases matching prefix '${versionPrefix}' found! Please check the version.`);
          } else {
            core.setFailed(`No LLVM releases found! Please release LLVM before running this workflow.`);
          }
          process.exit();

    - name: download
      shell: bash
      run: |
        # Pass the authorization token to allow downloading draft release assets.
        curl -sSLo llvm.tar.gz -H "Authorization: Bearer ${{ github.token }}" -H "Accept: application/octet-stream" ${{ steps.find.outputs.result }}

    - name: unpack
      shell: bash
      run: |
        tar -xf llvm.tar.gz
        rm llvm.tar.gz