name: Label Pull Requests

on:
  pull_request_target:
    types: [opened, synchronize, reopened, ready_for_review]

permissions:
  contents: read
  pull-requests: write

jobs:
  apply-labels:
    name: Apply area and size labels
    runs-on: ubuntu-latest
    steps:
      - name: Apply area labels
        uses: actions/labeler@v6
        with:
          repo-token: ${{ secrets.GITHUB_TOKEN }}
          sync-labels: false

      - name: Apply size label
        uses: actions/github-script@v8
        with:
          script: |
            const owner = context.repo.owner;
            const repo = context.repo.repo;
            const pull_number = context.payload.pull_request.number;
            const sizeLabels = ['size: XS', 'size: S', 'size: M', 'size: L', 'size: XL', 'size: XXL'];

            const { data: pull } = await github.rest.pulls.get({
              owner,
              repo,
              pull_number,
            });

            const totalChanges = pull.additions + pull.deletions;
            let nextSize = 'size: XXL';
            if (totalChanges < 50) nextSize = 'size: XS';
            else if (totalChanges < 200) nextSize = 'size: S';
            else if (totalChanges < 500) nextSize = 'size: M';
            else if (totalChanges < 1000) nextSize = 'size: L';
            else if (totalChanges < 2000) nextSize = 'size: XL';

            const currentLabels = pull.labels.map((label) => label.name);
            const existingSizeLabels = currentLabels.filter((label) => sizeLabels.includes(label));
            const labelsToRemove = existingSizeLabels.filter((label) => label !== nextSize);

            for (const label of labelsToRemove) {
              try {
                await github.rest.issues.removeLabel({
                  owner,
                  repo,
                  issue_number: pull_number,
                  name: label,
                });
              } catch (error) {
                if (error.status !== 404) {
                  throw error;
                }
              }
            }

            if (!currentLabels.includes(nextSize)) {
              await github.rest.issues.addLabels({
                owner,
                repo,
                issue_number: pull_number,
                labels: [nextSize],
              });
            }