name: Check File Size

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

jobs:
  check-size:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Check file sizes
        id: check_files
        continue-on-error: true
        run: |
          set -euo pipefail

          BASE_SHA="${{ github.event.pull_request.base.sha }}"
          HEAD_SHA="${{ github.sha }}"
          MAX_SIZE=$((1024 * 1024)) # 1 MB

          echo "Comparing changes between $BASE_SHA and $HEAD_SHA"

          failed=0
          files_over=()

          while IFS= read -r -d '' file; do
            if [ -f "$file" ]; then
                size=$(wc -c < "$file")
                if [ "$size" -gt "$MAX_SIZE" ]; then
                  echo "Error: $file ($size bytes)"
                  files_over+=("- $file ($size bytes)")
                  failed=1
                fi
            fi
          done < <(
            git diff --name-only -z --diff-filter=AMCR "$BASE_SHA" "$HEAD_SHA"
          )

          if [ "$failed" -eq 1 ]; then
            {
              echo "file_list<<EOF"
              printf "%s\n" "${files_over[@]}"
              echo "EOF"
            } >> "$GITHUB_OUTPUT"
            exit 1
          else
            echo "All changed files are under 1 MB."
          fi

      - name: Comment on PR and add label if size check failed
        if: steps.check_files.outcome == 'failure'
        uses: actions/github-script@v7
        with:
          script: |
            const fileList = `${{ steps.check_files.outputs.file_list }}`;
            if (fileList) {
              const body = `
            我们注意到以下文件的大小超过了 1MB，请在压缩后再次提交 Pull Request：
            We have noted that the following files exceed 1MB in size. Please resubmit your pull request after compressing them:

            ${fileList}
            `.trim();
              
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body: body
              });

              throw new Error('File size check failed');
            }