name: Release Helm chart
on:
  workflow_dispatch:
env:
  CR_CONFIGFILE: "${{ github.workspace }}/source/.github/configs/cr.yaml"
  CT_CONFIGFILE: "${{ github.workspace }}/source/.github/configs/ct.yaml"
  CR_INDEX_PATH: "${{ github.workspace }}/.cr-index"
  CR_PACKAGE_PATH: "${{ github.workspace }}/.cr-release-packages"
  CR_TOOL_PATH: "${{ github.workspace }}/.cr-tool"
  CR_VERSION: "1.5.0"
permissions:
  contents: read
  id-token: write
jobs:
  setup:
    runs-on: ubuntu-latest
    outputs:
      changed: ${{ steps.list-changed.outputs.changed }}
      chartpath: ${{ steps.list-changed.outputs.chartpath }}
    steps:
    - name: Checkout
      uses: actions/checkout@v4
      with:
        fetch-depth: 0
        path: source

    - name: Install chart-testing
      uses: helm/chart-testing-action@v2

    - name: List changed charts
      id: list-changed
      run: |
        cd source

        latest_tag=$( if ! git describe --tags --abbrev=0 --match='helm-chart/*' 2> /dev/null ; then git rev-list --max-parents=0 --first-parent HEAD; fi )

        echo "Running: ct list-changed --config ${CT_CONFIGFILE} --since ${latest_tag} --target-branch ${{ github.ref_name }}"
        changed=$(ct list-changed --config "${CT_CONFIGFILE}" --since "${latest_tag}" --target-branch "${{ github.ref_name }}")
        echo "${changed}"

        num_changed=$(wc -l <<< ${changed})
        if [[ "${num_changed}" -gt "1" ]] ; then
          echo "More than one chart changed, exiting"
          exit 1
        fi
        if [[ -n "${changed}" ]]; then
          name=$(yq ".name" < ${changed}/Chart.yaml)
          version=$(yq ".version" < ${changed}/Chart.yaml)
          tagname="v${version}"

          if [ $(git tag -l "${tagname}") ]; then
            echo "Tag ${tagname} already exists, skipping release"
            echo "changed=false" >> $GITHUB_OUTPUT
          else
            echo "Releasing ${changed}"
            echo "changed=true" >> $GITHUB_OUTPUT
            echo "chartpath=${changed}" >> $GITHUB_OUTPUT
          fi
        else
          echo "No charts have changed, skipping release"
          echo "changed=false" >> $GITHUB_OUTPUT
        fi

  release:
    needs: [setup]
    runs-on: ubuntu-latest
    if: needs.setup.outputs.changed == 'true'
    steps:
    - uses: actions/create-github-app-token@v1
      id: app-token
      with:
        app-id: ${{ secrets.APP_ID }}
        private-key: ${{ secrets.PRIVATE_KEY }}
    - name: Checkout
      uses: actions/checkout@v4
      with:
        fetch-depth: 0
        path: source

    - name: Configure Git
      run: |
        cd source
        git config user.name "$GITHUB_ACTOR"
        git config user.email "$GITHUB_ACTOR@users.noreply.github.com"

    - name: Checkout helm-charts
      uses: actions/checkout@v4
      with:
        fetch-depth: 0
        repository: grafana/helm-charts
        path: helm-charts
        token: "${{ steps.app-token.outputs.token }}"

    - name: Configure Git for helm-charts
      run: |
        cd helm-charts
        git config user.name "$GITHUB_ACTOR"
        git config user.email "$GITHUB_ACTOR@users.noreply.github.com"

    - name: Set up Helm
      uses: azure/setup-helm@v4

    - name: Parse Chart.yaml
      id: parse-chart
      run: |
        cd source
        changed="${{ needs.setup.outputs.chartpath }}"
        description=$(yq ".description" < ${changed}/Chart.yaml)
        name=$(yq ".name" < ${changed}/Chart.yaml)
        version=$(yq ".version" < ${changed}/Chart.yaml)

        echo "chartpath=${changed}" >> $GITHUB_OUTPUT
        echo "desc=${description}" >> $GITHUB_OUTPUT
        echo "tagname=v${version}" >> $GITHUB_OUTPUT
        echo "packagename=${name}-${version}" >> $GITHUB_OUTPUT

    - name: Install CR tool
      run: |
        mkdir "${CR_TOOL_PATH}"
        mkdir "${CR_PACKAGE_PATH}"
        mkdir "${CR_INDEX_PATH}"
        curl -sSLo cr.tar.gz "https://github.com/helm/chart-releaser/releases/download/v${CR_VERSION}/chart-releaser_${CR_VERSION}_linux_amd64.tar.gz"
        tar -xzf cr.tar.gz -C "${CR_TOOL_PATH}"
        rm -f cr.tar.gz

    - name: Create Helm package
      run: |
        cd source
        helm repo add grafana https://grafana.github.io/helm-charts
        helm repo add minio https://charts.min.io

        "${CR_TOOL_PATH}/cr" package "${{ steps.parse-chart.outputs.chartpath }}" --config "${CR_CONFIGFILE}" --package-path "${CR_PACKAGE_PATH}"

    - name: Make a release on this repo
      uses: softprops/action-gh-release@v2
      with:
        name: ${{ steps.parse-chart.outputs.tagname }}
        repository: grafana/meta-monitoring-chart
        tag_name: ${{ steps.parse-chart.outputs.tagname }}
        token: ${{ steps.app-token.outputs.token }}
        generate_release_notes: true
        files: |
          ${{ env.CR_PACKAGE_PATH }}/${{ steps.parse-chart.outputs.packagename }}.tgz

    # Note that this creates a release in grafana/helm-charts with a new tag.
    # The tag name in grafana/helm-charts is <package>-<version>, while the
    # tag name for grafana/meta-monitoring-chart is <version>.
    - name: Make release on Helm Charts
      uses: softprops/action-gh-release@v2
      with:
        name: ${{ steps.parse-chart.outputs.packagename }}
        repository: grafana/helm-charts
        tag_name: ${{ steps.parse-chart.outputs.packagename }}
        token: ${{ steps.app-token.outputs.token }}
        body: |
          ${{ steps.parse-chart.outputs.desc }}

          Source commit: https://github.com/${{ github.repository }}/commit/${{ github.sha }}

          Tag on source: https://github.com/${{ github.repository }}/releases/tag/${{ steps.parse-chart.outputs.tagname }}
        files: |
          ${{ env.CR_PACKAGE_PATH }}/${{ steps.parse-chart.outputs.packagename }}.tgz

    - name: Update helm-charts index.yaml
      run: |
        cd helm-charts
        "${CR_TOOL_PATH}/cr" index --config "${CR_CONFIGFILE}" --token "${{ steps.app-token.outputs.token }}" --index-path "${CR_INDEX_PATH}" --package-path "${CR_PACKAGE_PATH}" --push