name: Label contributor intent

on:
  issues:
    types: [opened, edited]

permissions:
  issues: write

env:
  INTENDS_TO_PR_LABEL: intends-to-pr

jobs:
  label:
    if: ${{ !github.event.issue.pull_request }}
    runs-on: ubuntu-latest

    steps:
      - name: Sync intends-to-pr label
        uses: actions/github-script@v9
        with:
          script: |
            const label = process.env.INTENDS_TO_PR_LABEL;
            const body = context.payload.issue.body || '';
            const issueNumber = context.payload.issue.number;
            const { owner, repo } = context.repo;
            const checkedIntentPattern = /^\s*-\s*\[[xX]\]\s*I intend to open a PR for this (?:change|issue)\.\s*$/m;
            const uncheckedIntentPattern = /^\s*-\s*\[ \]\s*I intend to open a PR for this (?:change|issue)\.\s*$/m;
            const cliIntentPattern = /^\s*\/i-intend-to-pr\s*$/m;
            const shouldAddLabel = checkedIntentPattern.test(body) || cliIntentPattern.test(body);
            const shouldRemoveLabel = uncheckedIntentPattern.test(body);
            const labels = context.payload.issue.labels.map((item) =>
              typeof item === 'string' ? item : item.name,
            );
            const hasLabel = labels.includes(label);

            if (shouldAddLabel && hasLabel) {
              console.log(`${label} is already present on #${issueNumber}.`);
              return;
            }

            if (shouldRemoveLabel && !hasLabel) {
              console.log(`${label} is already absent from #${issueNumber}.`);
              return;
            }

            if (!shouldAddLabel && !shouldRemoveLabel) {
              console.log(`No contribution intent signal found for #${issueNumber}.`);
              return;
            }

            if (shouldAddLabel) {
              try {
                await github.rest.issues.getLabel({ owner, repo, name: label });
              } catch (error) {
                if (error.status !== 404) {
                  throw error;
                }

                await github.rest.issues.createLabel({
                  owner,
                  repo,
                  name: label,
                  color: '0E8A16',
                  description: 'Contributor intends to open a PR for this issue.',
                });
              }

              await github.rest.issues.addLabels({
                owner,
                repo,
                issue_number: issueNumber,
                labels: [label],
              });
              console.log(`Added ${label} to #${issueNumber}.`);
              return;
            }

            try {
              await github.rest.issues.removeLabel({
                owner,
                repo,
                issue_number: issueNumber,
                name: label,
              });
              console.log(`Removed ${label} from #${issueNumber}.`);
            } catch (error) {
              if (error.status !== 404) {
                throw error;
              }
              console.log(`${label} was already absent from #${issueNumber}.`);
            }