name: Update Flake Inputs
on:
  schedule:
    # Every day at 03:30 JST (18:30 UTC on the previous day).
    - cron: "30 18 * * *"
  workflow_dispatch:
    inputs:
      input:
        description: Update only this flake input (empty updates all inputs)
        required: false
        type: string
      skip-delay:
        description: Update to the latest revision without the three-day delay
        required: false
        default: false
        type: boolean
      auto-merge:
        description: Enable auto-merge after required checks pass
        required: false
        default: true
        type: boolean
permissions:
  contents: write
  pull-requests: write
concurrency:
  group: update-flake-inputs
  cancel-in-progress: false
jobs:
  discover:
    name: Discover flake inputs
    runs-on: ubuntu-latest
    timeout-minutes: 5
    outputs:
      matrix: ${{ steps.inputs.outputs.matrix }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false
      - name: Build update matrix
        id: inputs
        env:
          REQUESTED_INPUT: ${{ inputs.input }}
        run: |
          set -euo pipefail

          github_inputs="$(
            jq -c '
              . as $lock
              | [
                  $lock.nodes.root.inputs
                  | to_entries[]
                  | .key as $name
                  | (
                      .value
                      | if type == "array" then .[0] else . end
                    ) as $node
                  | select($lock.nodes[$node].locked.type == "github")
                  | $name
                ]
              | sort
            ' flake.lock
          )"

          if [ -n "$REQUESTED_INPUT" ]; then
            if ! jq -e --arg input "$REQUESTED_INPUT" 'index($input) != null' <<< "$github_inputs" >/dev/null; then
              echo "::error::Unknown or unsupported flake input: $REQUESTED_INPUT"
              exit 1
            fi
            matrix="$(jq -cn --arg input "$REQUESTED_INPUT" '{input: [$input]}')"
          else
            matrix="$(jq -cn --argjson inputs "$github_inputs" '{input: $inputs}')"
          fi

          echo "matrix=$matrix" >> "$GITHUB_OUTPUT"
          echo "Update matrix: $matrix"
  update:
    name: Update ${{ matrix.input }}
    needs: discover
    if: ${{ needs.discover.outputs.matrix != '{"input":[]}' }}
    runs-on: ubuntu-latest
    timeout-minutes: 30
    strategy:
      fail-fast: false
      max-parallel: 4
      matrix: ${{ fromJSON(needs.discover.outputs.matrix) }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          fetch-depth: 0
          token: ${{ secrets.RENOVATE_TOKEN }}
      - name: Install Nix
        uses: cachix/install-nix-action@630ae543ea3a38a9a4166f03376c02c50f408342 # v31.11.0
        with:
          extra_nix_config: |
            experimental-features = nix-command flakes
            accept-flake-config = true
            access-tokens = github.com=${{ secrets.RENOVATE_TOKEN }}
      - name: Update input
        uses: ./.github/actions/update-flake-input
        with:
          input-name: ${{ matrix.input }}
          github-token: ${{ secrets.RENOVATE_TOKEN }}
          skip-delay: ${{ github.event_name == 'workflow_dispatch' && inputs.skip-delay }}
          auto-merge: ${{ github.event_name != 'workflow_dispatch' || inputs.auto-merge }}