name: Auto Review

on:
  pull_request_target:
    types: [opened, synchronize]

jobs:
  review:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Get PR diff
        env:
          GH_TOKEN: ${{ github.token }}
        run: |
          gh pr diff ${{ github.event.pull_request.number }} > /tmp/pr.diff
          head -c 30000 /tmp/pr.diff > /tmp/pr_truncated.diff

      - name: Review with DeepSeek
        id: review
        env:
          DEEPSEEK_API_KEY: ${{ secrets.DEEPSEEK_API_KEY }}
          PR_TITLE: ${{ github.event.pull_request.title }}
          PR_BODY: ${{ github.event.pull_request.body }}
        run: |
          python3 - <<'PYEOF'
          import os, json, urllib.request

          diff = open("/tmp/pr_truncated.diff").read()
          title = os.environ.get("PR_TITLE", "")
          body = os.environ.get("PR_BODY", "")[:2000]
          api_key = os.environ["DEEPSEEK_API_KEY"]

          payload = json.dumps({
              "model": "deepseek-chat",
              "messages": [
                  {
                      "role": "system",
                      "content": "你是一个专业的代码审查员。请审查以下 Pull Request 的代码变更，给出简洁的中文评审意见。重点关注：1. 潜在的 bug 或逻辑错误 2. 安全问题 3. 性能问题 4. 代码风格和可读性。如果代码没有问题，简单说 LGTM 并给出简短总结。不要逐行重复代码。"
                  },
                  {
                      "role": "user",
                      "content": f"PR 标题: {title}\n\nPR 描述: {body}\n\n代码变更:\n{diff}"
                  }
              ],
              "max_tokens": 2000
          }).encode()

          req = urllib.request.Request(
              "https://api.deepseek.com/chat/completions",
              data=payload,
              headers={
                  "Authorization": f"Bearer {api_key}",
                  "Content-Type": "application/json",
              },
          )

          with urllib.request.urlopen(req, timeout=120) as resp:
              data = json.loads(resp.read())

          review = data["choices"][0]["message"]["content"]

          with open(os.environ["GITHUB_OUTPUT"], "a") as f:
              delim = "EOF_REVIEW"
              f.write(f"comment<<{delim}\n{review}\n{delim}\n")
          PYEOF

      - name: Post review comment
        env:
          GH_TOKEN: ${{ github.token }}
          REVIEW: ${{ steps.review.outputs.comment }}
        run: |
          printf '🤖 **Auto Review by DeepSeek**\n\n%s' "$REVIEW" > /tmp/comment.md
          gh pr comment ${{ github.event.pull_request.number }} --body-file /tmp/comment.md