# .github/actions/checkout/action.yml

# This is essentially the same as actions/checkout, but will
# fallback to the default branch if the ref does not exist.
# https://github.com/actions/checkout

name: Checkout

inputs:
  fetch-depth:
    default: 1
    required: false
    type: number
  path:
    default: ''
    required: false
    type: string
  repository:
    default: ${{ github.repository }}
    required: false
    type: string
  ref:
    default: ''
    required: false
    type: string
  token:
    default: ${{ github.token }}
    required: false
    type: string

runs:
  using: composite

  steps:
  - id: repo
    shell: bash
    env:
      GH_TOKEN: ${{ inputs.token }}
    run: |
      if [[ -z "${{ inputs.ref }}" ]]
      then
        if [[ "${{ inputs.repository }}" != "${{ github.repository }}" ]]
        then
          USING="default branch"
        else
          USING="$(gh api /repos/${{ inputs.repository }}/commits/${{ github.sha }}/branches-where-head --jq '.[0].name')"
        fi
        echo "::notice::Checkout: ${{ inputs.repository }} using ${USING}"
        echo "::set-output name=ref-exists::true"
      else
        if git ls-remote --heads --quiet --exit-code https://${{ inputs.token }}@github.com/${{ inputs.repository }}.git ${{ inputs.ref }}
        then
          echo "::notice::Checkout: ${{ inputs.repository }} using ${{ inputs.ref }}"
          echo "::set-output name=ref-exists::true"
        else
          USING="$(gh api /repos/${{ inputs.repository }} --jq '.default_branch')"
          echo "::notice::Checkout: ${{ inputs.repository }} does not have ref ${{ inputs.ref }} (fallback to ${USING})"
          echo "::set-output name=ref-exists::false"
          echo "::set-output name=default-branch::${USING}"
        fi
      fi

  - if: steps.repo.outputs.ref-exists == 'true'
    uses: actions/checkout@v3
    with:
      fetch-depth: ${{ inputs.fetch-depth }}
      path: ${{ inputs.path }}
      repository: ${{ inputs.repository }}
      ref: ${{ inputs.ref }}
      token: ${{ inputs.token }}

  - if: steps.repo.outputs.ref-exists == 'false'
    uses: actions/checkout@v3
    with:
      fetch-depth: ${{ inputs.fetch-depth }}
      path: ${{ inputs.path }}
      repository: ${{ inputs.repository }}
      ref: ${{ steps.repo.outputs.default-branch }}
      token: ${{ inputs.token }}