name: NanoKVM Release

on:
  workflow_dispatch:
    inputs:
      tag:
        description: Existing numeric tag to release, e.g. 2.5.0
        required: true
        type: string
      release_action:
        description: Publish a release or promote a tested prerelease
        required: true
        type: choice
        options:
          - publish-prerelease
          - publish-stable
          - promote-stable

# Latest is repository-global, so all Release changes must be serialized.
concurrency:
  group: nanokvm-github-release
  cancel-in-progress: false

jobs:
  validate:
    name: Resolve release tag
    runs-on: ubuntu-latest
    permissions:
      contents: read
    outputs:
      source_sha: ${{ steps.tag.outputs.source_sha }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          persist-credentials: false

      - name: Verify tag
        id: tag
        env:
          TAG: ${{ inputs.tag }}
        run: |
          SOURCE_SHA=$(./scripts/verify-release-tag.sh "$TAG")
          echo "source_sha=$SOURCE_SHA" >> "$GITHUB_OUTPUT"

  package:
    name: Build tag package
    needs: validate
    if: inputs.release_action != 'promote-stable'
    permissions:
      contents: read
      packages: read
    uses: ./.github/workflows/package.yml
    with:
      ref: ${{ needs.validate.outputs.source_sha }}
      version: ${{ inputs.tag }}

  publish:
    name: Publish GitHub release
    needs:
      - validate
      - package
    if: inputs.release_action != 'promote-stable'
    runs-on: ubuntu-latest
    permissions:
      contents: write

    steps:
      - name: Checkout release tooling
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          persist-credentials: false

      - name: Download package artifact
        uses: actions/download-artifact@v4
        with:
          name: ${{ needs.package.outputs.artifact_name }}
          path: build/release

      - name: Publish release
        env:
          GH_REPO: ${{ github.repository }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          RELEASE_ACTION: ${{ inputs.release_action }}
          SOURCE_SHA: ${{ needs.validate.outputs.source_sha }}
          TAG: ${{ inputs.tag }}
        run: |
          ./scripts/verify-release-assets.sh build/release "$TAG"

          case "$RELEASE_ACTION" in
            publish-prerelease) IS_PRERELEASE=true ;;
            publish-stable) IS_PRERELEASE=false ;;
            *)
              echo "::error::invalid publish action '$RELEASE_ACTION'"
              exit 1
              ;;
          esac

          ENDPOINT="repos/${GITHUB_REPOSITORY}/releases/tags/${TAG}"
          set +e
          HEADERS=$(gh api --include --silent "$ENDPOINT" 2>&1)
          API_STATUS=$?
          set -e
          HTTP_STATUS=$(printf '%s\n' "$HEADERS" | awk '
            $1 ~ /^HTTP\// { status = $2 }
            END { print status }
          ')
          if [ "$API_STATUS" -eq 0 ] && [ "$HTTP_STATUS" = 200 ]; then
            echo "::error::release or draft '$TAG' already exists"
            echo "Publishing is one-shot. Inspect it at https://github.com/${GITHUB_REPOSITORY}/releases."
            exit 1
          fi
          if [ "$API_STATUS" -eq 0 ] || [ "$HTTP_STATUS" != 404 ]; then
            echo "::error::failed to query release '$TAG' (HTTP status: ${HTTP_STATUS:-unknown})"
            printf '%s\n' "$HEADERS" >&2
            exit 1
          fi

          TARBALL="build/release/nanokvm_${TAG}.tar.gz"
          SHA256=$(sha256sum "$TARBALL" | cut -d' ' -f1)
          SHA512=$(jq -er '.sha512' build/release/latest.json)
          # Backticks below are intentional Markdown, not command substitution.
          # shellcheck disable=SC2016
          NOTES=$(printf '%s\n' \
            "Application package for NanoKVM ${TAG}." \
            '' \
            '### Checksums' \
            '' \
            '`SHA-256` (hex):' \
            '' \
            "    ${SHA256}" \
            '' \
            '`SHA-512` (base64, as expected by the on-device updater):' \
            '' \
            "    ${SHA512}" \
            '' \
            'To offer this build over OTA, publish it through the separate CDN workflow.')

          STATE_ARGS=(--prerelease="$IS_PRERELEASE")
          if [ "$IS_PRERELEASE" = true ]; then
            STATE_ARGS+=(--latest=false)
          fi

          ./scripts/verify-release-tag.sh "$TAG" "$SOURCE_SHA" >/dev/null
          gh release create "$TAG" \
            --verify-tag \
            --title "$TAG" \
            --notes "$NOTES" \
            "${STATE_ARGS[@]}" \
            "$TARBALL" build/release/latest.json build/release/sha256.txt

      - name: Summary
        env:
          RELEASE_ACTION: ${{ inputs.release_action }}
          SOURCE_SHA: ${{ needs.validate.outputs.source_sha }}
          TAG: ${{ inputs.tag }}
        run: |
          {
            echo '### NanoKVM GitHub Release published'
            echo
            echo "- Tag: \`$TAG\`"
            echo "- Commit: \`$SOURCE_SHA\`"
            echo "- Action: \`$RELEASE_ACTION\`"
            echo
            echo 'No CDN object was uploaded.'
          } >> "$GITHUB_STEP_SUMMARY"

  promote:
    name: Promote verified prerelease
    needs: validate
    if: inputs.release_action == 'promote-stable'
    runs-on: ubuntu-latest
    permissions:
      contents: write

    steps:
      - name: Checkout release tooling
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          persist-credentials: false

      - name: Verify and promote release
        env:
          GH_REPO: ${{ github.repository }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          SOURCE_SHA: ${{ needs.validate.outputs.source_sha }}
          TAG: ${{ inputs.tag }}
        run: |
          RELEASE_JSON=$(gh api "repos/${GITHUB_REPOSITORY}/releases/tags/${TAG}")
          if [ "$(jq -r '.draft' <<< "$RELEASE_JSON")" != false ]; then
            echo "::error::release '$TAG' is a draft"
            exit 1
          fi
          if [ "$(jq -r '.prerelease' <<< "$RELEASE_JSON")" != true ]; then
            echo "::error::release '$TAG' is not a prerelease"
            exit 1
          fi

          CURRENT_ASSETS=$(jq -r '.assets[].name' <<< "$RELEASE_JSON" | LC_ALL=C sort)
          EXPECTED_ASSETS=$(printf '%s\n' \
            latest.json "nanokvm_${TAG}.tar.gz" sha256.txt | LC_ALL=C sort)
          if [ "$CURRENT_ASSETS" != "$EXPECTED_ASSETS" ]; then
            echo "::error::release '$TAG' does not have the exact expected asset set"
            exit 1
          fi

          mkdir -p build/release
          gh release download "$TAG" --dir build/release \
            --pattern "nanokvm_${TAG}.tar.gz" \
            --pattern latest.json \
            --pattern sha256.txt
          ./scripts/verify-release-assets.sh build/release "$TAG"

          ./scripts/verify-release-tag.sh "$TAG" "$SOURCE_SHA" >/dev/null
          gh release edit "$TAG" --prerelease=false --latest
          ./scripts/verify-release-tag.sh "$TAG" "$SOURCE_SHA" >/dev/null

          if [ "$(gh api "repos/${GITHUB_REPOSITORY}/releases/tags/${TAG}" --jq '.prerelease')" != false ]; then
            echo "::error::release '$TAG' was not promoted"
            exit 1
          fi
          if [ "$(gh api "repos/${GITHUB_REPOSITORY}/releases/latest" --jq '.tag_name')" != "$TAG" ]; then
            echo "::error::release '$TAG' was not marked latest"
            exit 1
          fi

      - name: Summary
        env:
          SOURCE_SHA: ${{ needs.validate.outputs.source_sha }}
          TAG: ${{ inputs.tag }}
        run: |
          {
            echo '### NanoKVM prerelease promoted'
            echo
            echo "- Tag: \`$TAG\`"
            echo "- Commit: \`$SOURCE_SHA\`"
            echo '- Assets: unchanged and checksum-verified'
            echo
            echo 'No package was rebuilt and no CDN object was uploaded.'
          } >> "$GITHUB_STEP_SUMMARY"