name: GitHub - PR Contribution Guidelines

on:
  pull_request_target:
    types: [opened, reopened]

jobs:
  # Ensures PR commits were not added via the GitHub Web UI, which typically indicates
  # the contributor hasn't tested their changes in a local development environment.
  no-web-commits:
    name: No Commits on GitHub Web
    runs-on: ubuntu-24.04
    outputs:
      is_allow_listed: ${{ steps.pr_author.outputs.is_allow_listed }}
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
        with:
          sparse-checkout: .github/scripts/pr-guidelines
          sparse-checkout-cone-mode: false

      - name: Check if PR author is allow-listed
        id: pr_author
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        with:
          # GITHUB_TOKEN does not have the read:org permission needed for this call
          # while CAMPERBOT_NO_TRANSLATE does, since it is a PAT for the camperbot account with read:org scope
          github-token: ${{ secrets.CAMPERBOT_NO_TRANSLATE }}
          script: |
            const fn = require('./.github/scripts/pr-guidelines/check-allow-list.js');
            await fn({ github, context, core });

      - name: Check if commits are made on GitHub Web UI
        id: check-commits
        if: steps.pr_author.outputs.is_allow_listed == 'false'
        env:
          HEAD_REF: ${{ github.head_ref }}
        run: |
          PR_NUMBER=$(jq --raw-output .pull_request.number "$GITHUB_EVENT_PATH")
          COMMITS_URL="https://api.github.com/repos/$GITHUB_REPOSITORY/pulls/$PR_NUMBER/commits"
          HAS_GITHUB_SIGNED_COMMIT=$(curl --header "Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}" "$COMMITS_URL" | jq '[.[] | select(.commit.committer.name == "GitHub") | select(.commit.message | test("revert"; "i") | not)] | length > 0')
          # GitHub Codespaces also produces GitHub-signed commits, but Codespaces users
          # work on descriptively named branches. The web editor defaults to patch-N branches.
          IS_PATCH_BRANCH=false
          if [[ "$HEAD_REF" =~ ^patch-[0-9]+$ ]]; then
            IS_PATCH_BRANCH=true
          fi
          if [ "$HAS_GITHUB_SIGNED_COMMIT" = "true" ] && [ "$IS_PATCH_BRANCH" = "true" ]; then
            echo "IS_GITHUB_COMMIT=true" >> $GITHUB_ENV
          fi

      - name: Add comment on PR if commits are made on GitHub Web UI
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        if: steps.pr_author.outputs.is_allow_listed == 'false' && env.IS_GITHUB_COMMIT == 'true'
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            core.setFailed("Commits were added via the GitHub Web UI.");
            await github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: "Thanks for your pull request.\n\n**Please do not add commits via the GitHub Web UI.**\n\nIt generally means you have yet to test these changes in a development setup or complete any prerequisites. We need you to follow the guides mentioned in the checklist. Please revalidate these changes in a developer environment and confirm how you validated your changes.\n\nHappy contributing!\n\n---\n_**Note:** This message was automatically generated by a bot. If you feel this message is in error or would like help resolving it, feel free to reach us [in our contributor chat](https://discord.gg/PRyKn3Vbay)._"
            });

      - name: Add deprioritized label
        if: failure()
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            await github.rest.issues.addLabels({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              labels: ['deprioritized']
            });

  # Normalizes PR titles to follow Conventional Commits format, applying fuzzy fixes
  # for common mistakes like typos, missing colons, or incorrect spacing.
  fix-pr-title:
    name: Fix PR Title
    runs-on: ubuntu-24.04
    needs: no-web-commits
    if: needs.no-web-commits.result == 'success'
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
        with:
          sparse-checkout: .github/scripts/pr-guidelines
          sparse-checkout-cone-mode: false

      - uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const fn = require('./.github/scripts/pr-guidelines/fix-pr-title.js');
            await fn({ github, context });

  # Checks that the PR description still contains the required template.
  # The first 3 checkboxes must be ticked ([x] or [X]).
  # The last checkbox (tested locally) is acceptable to leave unticked
  # but removing the entire template is not.
  check-pr-template:
    name: Check PR Template
    runs-on: ubuntu-24.04
    needs: no-web-commits
    if: needs.no-web-commits.result == 'success'
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
        with:
          sparse-checkout: .github/scripts/pr-guidelines
          sparse-checkout-cone-mode: false

      - uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const fn = require('./.github/scripts/pr-guidelines/check-pr-template.js');
            await fn({ github, context, isAllowListed: '${{ needs.no-web-commits.outputs.is_allow_listed }}' });

  # Verifies that each PR references a linked, triaged issue before it can be reviewed.
  check-linked-issue:
    name: Check Linked Issue
    runs-on: ubuntu-24.04
    needs: no-web-commits
    if: needs.no-web-commits.result == 'success'
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
        with:
          sparse-checkout: .github/scripts/pr-guidelines
          sparse-checkout-cone-mode: false

      - uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const fn = require('./.github/scripts/pr-guidelines/check-linked-issue.js');
            await fn({ github, context, isAllowListed: '${{ needs.no-web-commits.outputs.is_allow_listed }}' });