name: Docs Acknowledgement

on:
  pull_request:
    types: [opened, edited, synchronize]

permissions:
  contents: read
  pull-requests: read

jobs:
  docs-ack:
    name: Require docs PR URL or explicit "not needed"
    runs-on: ubuntu-latest

    steps:
      - name: Read PR body
        id: body
        run: |
          BODY=$(jq -r '.pull_request.body // ""' "$GITHUB_EVENT_PATH")
          echo "body<<EOF" >> $GITHUB_OUTPUT
          echo "$BODY" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT

      - name: Validate checkbox selection
        id: validate
        run: |
          body='${{ steps.body.outputs.body }}'

          added_checked=$(printf "%s" "$body" | grep -E '^- \[x\] I added/updated documentation' -i | wc -l | tr -d ' ')
          noneed_checked=$(printf "%s" "$body" | grep -E '^- \[x\] Documentation is \*\*not needed\*\*' -i | wc -l | tr -d ' ')

          if [ "$added_checked" -eq 1 ] && [ "$noneed_checked" -eq 1 ]; then
            echo "::error::Choose exactly one: either 'docs added' OR 'not needed'."
            exit 1
          fi

          if [ "$added_checked" -eq 0 ] && [ "$noneed_checked" -eq 0 ]; then
            echo "::error::You must check exactly one docs option in the PR template."
            exit 1
          fi

          if [ "$added_checked" -eq 1 ]; then
            echo "mode=added" >> $GITHUB_OUTPUT
          else
            echo "mode=noneed" >> $GITHUB_OUTPUT
          fi

      - name: Extract docs PR URL (when 'docs added')
        if: steps.validate.outputs.mode == 'added'
        id: extract
        run: |
          body='${{ steps.body.outputs.body }}'

          # Strictly require HTTPS and that it's a PR in netbirdio/docs
          # Examples accepted:
          #   https://github.com/netbirdio/docs/pull/1234
          url=$(printf "%s" "$body" | grep -Eo 'https://github\.com/netbirdio/docs/pull/[0-9]+' | head -n1 || true)

          if [ -z "$url" ]; then
            echo "::error::You checked 'docs added' but didn't include a valid HTTPS PR link to netbirdio/docs (e.g., https://github.com/netbirdio/docs/pull/1234)."
            exit 1
          fi

          pr_number=$(echo "$url" | sed -E 's#.*/pull/([0-9]+)$#\1#')
          echo "url=$url" >> $GITHUB_OUTPUT
          echo "pr_number=$pr_number" >> $GITHUB_OUTPUT

      - name: Verify docs PR exists (and is open or merged)
        if: steps.validate.outputs.mode == 'added'
        uses: actions/github-script@v7
        id: verify
        with:
          pr_number: ${{ steps.extract.outputs.pr_number }}
          script: |
            const prNumber = parseInt(core.getInput('pr_number'), 10);
            const { data } = await github.rest.pulls.get({
              owner: 'netbirdio',
              repo: 'docs',
              pull_number: prNumber
            });

            // Allow open or merged PRs
            const ok = data.state === 'open' || data.merged === true;
            core.setOutput('state', data.state);
            core.setOutput('merged', String(!!data.merged));
            if (!ok) {
              core.setFailed(`Docs PR #${prNumber} exists but is neither open nor merged (state=${data.state}, merged=${data.merged}).`);
            }
          result-encoding: string
          github-token: ${{ secrets.GITHUB_TOKEN }}

      - name: All good
        run: echo "Documentation requirement satisfied ✅"