on:
  workflow_dispatch:
  schedule:
    # 03:42 on Saturdays
    - cron: '42 3 * * 6'
env:
  PR_TITLE: Weekly `cargo update` of dependencies
  PR_MESSAGE: |
    Automation to keep dependencies in `Cargo.lock` current.

    The following is the output from `cargo update`:
  COMMIT_MESSAGE: "chore(deps): cargo update"
jobs:
  update-cargo:
    runs-on: nixos
    env:
      BRANCH_NAME: cargo-update
    steps:
      - uses: https://git.salame.cl/actions/checkout@v4
      - run: nix --version
      - run: nix run .#cargo-update
      - name: craft PR body and commit message
        run: |
          set -xeuo pipefail

          echo "${COMMIT_MESSAGE}" > commit.txt
          printf '\n\n' >> commit.txt
          cat cargo_update.log >> commit.txt

          echo "${PR_MESSAGE}" > body.md
          echo '```txt' >> body.md
          cat cargo_update.log >> body.md
          echo '```' >> body.md
      - name: commit
        run: |
          set -xeuo pipefail

          git config user.name forgejo-actions
          git config user.email forgejo-actions@salame.cl
          git switch --force-create "$BRANCH_NAME"
          git add ./Cargo.lock
          DIFF="$(git diff --staged)"
          if [[ "$DIFF" == "" ]]; then
            echo "Cargo.lock was not changed, bailing out and not making a PR"
            exit 1
          fi
          git commit --no-verify --file=commit.txt
      - name: push
        run: |
          set -xeuo pipefail
          git push --no-verify --force --set-upstream origin "$BRANCH_NAME"
      - name: open new pull request
        env:
          # We have to use a Personal Access Token (PAT) here.
          # PRs opened from a workflow using the standard `GITHUB_TOKEN` in GitHub Actions
          # do not automatically trigger more workflows:
          # https://docs.github.com/en/actions/security-guides/automatic-token-authentication#using-the-github_token-in-a-workflow
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          curl -X POST \
            -H "Authorization: token $GITHUB_TOKEN" \
            -H 'Content-Type: application/json' \
            -d "$(
              echo '{}' |
                jq --arg body "$(cat body.md)" \
                  --arg title "$COMMIT_MESSAGE" \
                  --arg head "$BRANCH_NAME" \
                  '{"body": $body, "title": $title, "head": $head, "base": "main"}'
            )" \
            "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/pulls"