name: First commit message adheres to guidelines

on:
  pull_request_target:
    branches:
      - main

env:
  NODE_VERSION: lts/*

permissions:
  pull-requests: read

concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
  cancel-in-progress: true

jobs:
  lint-commit-message:
    name: lint-commit-message
    runs-on: ubuntu-slim
    steps:
      - name: Install Node.js
        uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1  # v7.1.0
        with:
          node-version: ${{ env.NODE_VERSION }}
      - name: Validate first commit message
        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3  # v9.0.0
        with:
          script: |
            const { data: [commit] } = await github.rest.pulls.listCommits({
              ...context.repo,
              pull_number: context.issue.number,
              per_page: 1,
            });
            if (!commit) {
              throw new Error('No commits found in pull request');
            }
            const { exitCode, stdout, stderr } = await exec.getExecOutput('npx', [
              '-q', '--yes', '--ignore-scripts', 'core-validate-commit@6.0.0',
              '--no-validate-metadata', '--tap', '-',
            ], {
              cwd: process.env.RUNNER_TEMP,
              input: Buffer.from(JSON.stringify([{
                id: commit.sha,
                message: commit.commit.message,
                author: commit.commit.author,
              }])),
              silent: true,
              ignoreReturnCode: true,
            });
            if (exitCode !== 0) {
              core.setFailed(stdout + stderr || 'Commit message validation failed');
            } else {
              core.info('First commit message passes validation');
            }