name: Code format

on:
  workflow_run:
    workflows: ["Code check"]
    types:
      - completed

permissions:
  actions: read
  contents: write
  pull-requests: read

jobs:
  format:
    if: |
      github.event.workflow_run.conclusion == 'failure' &&
      github.event.workflow_run.event == 'pull_request'
    runs-on: ubuntu-latest
    name: Run pnpm format:write
    steps:
      - name: Inspect failed workflow run
        id: meta
        uses: actions/github-script@v7
        with:
          script: |
            const pr = context.payload.workflow_run.pull_requests[0]

            if (!pr) {
              core.notice("Skipping because the failed run is not attached to a pull request.")
              core.setOutput("should_run", "false")
              return
            }

            const { data: pullRequest } = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: pr.number,
            })

            const { data: jobs } = await github.rest.actions.listJobsForWorkflowRun({
              owner: context.repo.owner,
              repo: context.repo.repo,
              run_id: context.payload.workflow_run.id,
              per_page: 100,
            })

            const formatJob = jobs.jobs.find((job) => job.name === "pnpm format:check")
            const sameRepo =
              pullRequest.head.repo.full_name === `${context.repo.owner}/${context.repo.repo}`
            const shouldRun = formatJob?.conclusion === "failure" && sameRepo

            if (!formatJob) {
              core.notice("Skipping because the format job could not be found in the failed run.")
            } else if (formatJob.conclusion !== "failure") {
              core.notice(
                `Skipping because the format job concluded with "${formatJob.conclusion}".`
              )
            }

            if (!sameRepo) {
              core.notice(
                `Skipping PR #${pullRequest.number} because its head branch lives in ${pullRequest.head.repo.full_name}.`
              )
            }

            core.setOutput("head_ref", pullRequest.head.ref)
            core.setOutput("should_run", shouldRun ? "true" : "false")

      - name: Checkout pull request branch
        if: steps.meta.outputs.should_run == 'true'
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          ref: ${{ steps.meta.outputs.head_ref }}

      - name: Install Node.js
        if: steps.meta.outputs.should_run == 'true'
        uses: actions/setup-node@v4
        with:
          node-version: 20

      - name: Install pnpm
        if: steps.meta.outputs.should_run == 'true'
        uses: pnpm/action-setup@v4
        with:
          version: 9.0.6
          run_install: false

      - name: Get pnpm store directory
        if: steps.meta.outputs.should_run == 'true'
        id: pnpm-cache
        run: |
          echo "pnpm_cache_dir=$(pnpm store path)" >> $GITHUB_OUTPUT

      - name: Setup pnpm cache
        if: steps.meta.outputs.should_run == 'true'
        uses: actions/cache@v4
        with:
          path: ${{ steps.pnpm-cache.outputs.pnpm_cache_dir }}
          key: ${{ runner.os }}-pnpm-store-${{ hashFiles('**/pnpm-lock.yaml') }}
          restore-keys: |
            ${{ runner.os }}-pnpm-store-

      - name: Install dependencies
        if: steps.meta.outputs.should_run == 'true'
        run: pnpm install

      - name: Apply formatting
        if: steps.meta.outputs.should_run == 'true'
        run: pnpm format:write

      - name: Commit formatting changes
        if: steps.meta.outputs.should_run == 'true'
        run: |
          if git diff --quiet; then
            echo "No formatting changes to commit."
            exit 0
          fi

          git config user.name "github-actions[bot]"
          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
          git add -A
          git commit -m "style: apply automated formatting"
          git push origin HEAD:${{ steps.meta.outputs.head_ref }}