name: Purge old images from main branch

on:
  workflow_dispatch:
  schedule:
    - cron: "0 0/3 * * *"
    - cron: "0 1/3 * * *"
    - cron: "0 2/3 * * *"

jobs:
  find-version:
    name: Delete version from main ref
    runs-on: ubuntu-22.04
    outputs:
      version: ${{ steps.find.outputs.version }}
    permissions:
      id-token: write
      contents: read
    steps:
      - name: Checkout
        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
        with:
          ref: ${{ github.head_ref }}

      - name: Login to AWS
        uses: aws-actions/configure-aws-credentials@e3dd6a429d7300a6a4c196c26e071d42e0343502 # v4.0.2
        with:
          role-to-assume: arn:aws:iam::795746500882:role/GithubConstellationVersionsAPIRead
          aws-region: eu-central-1

      - name: Determine stream
        id: stream
        run: |
          case "${{ github.event.schedule }}" in
            "0 0/3 * * *")
              echo "stream=debug" | tee -a "$GITHUB_OUTPUT"
              ;;
            "0 1/3 * * *")
              echo "stream=console" | tee -a "$GITHUB_OUTPUT"
              ;;
            "0 2/3 * * *")
              echo "stream=nightly" | tee -a "$GITHUB_OUTPUT"
              ;;
            *)
              echo "Unknown schedule: ${{ github.event.schedule }}"
              exit 1
              ;;
          esac

      - uses: ./.github/actions/setup_bazel_nix

      - name: List versions
        id: list
        uses: ./.github/actions/versionsapi
        with:
          command: list
          ref: main
          stream: ${{ steps.stream.outputs.stream }}

      - name: Find version to delete
        id: find
        shell: bash
        run: |
          versions=$(cat versionsapi_output.txt)
          echo "Found versions:"
          echo "${versions}"

          echo "Newest 10 versions shouldn't be deleted"
          deletable=$(echo "${versions}" | head -n -10)
          if [[ -z "${deletable}" ]]; then
            echo "No deletable versions found"
            exit 0
          fi
          echo "Found deletable versions:"
          echo "${deletable}"

          ver=$(echo "${deletable}" | head -n 1)
          echo "Deleting oldest version: ${ver}"
          echo "version=${ver}" | tee -a "$GITHUB_OUTPUT"

  delete:
    name: Delete version
    if: needs.find-version.outputs.version != ''
    permissions:
      id-token: write
      contents: read
    uses: ./.github/workflows/versionsapi.yml
    needs: find-version
    secrets: inherit
    with:
      command: remove
      version_path: ${{ needs.find-version.outputs.version }}