code_scan/scanner/ai_reviewer.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
AI 代码审查器
使用大模型进行智能代码审查
"""
import os
import re
import json
import logging
from typing import Dict, Any, List, Optional

from scanner.base import BaseScanner

logger = logging.getLogger(__name__)


class AIReviewer(BaseScanner):
    """AI 代码审查器"""

    def __init__(self, config: Dict[str, Any]):
        """
        初始化 AI 审查器

        Args:
            config: AI 配置
        """
        # 先初始化基类
        super().__init__(config.get('scanner', {}))
        
        self.config = config
        self.enabled = config.get('enabled', True)
        self.provider = config.get('provider', 'api')
        self.model = config.get('model', 'llama3')
        self.api_url = config.get('api_url', 'http://localhost:11434')
        self.api_key = config.get('api_key', '')
        self.max_lines = config.get('max_lines', 200)

        if not self.enabled:
            logger.info('AI 审查器已禁用')
            return

        logger.info(f'AI 审查器初始化: {self.provider}/{self.model}')

    def scan(self, repo_url: str, commit_id: Optional[str], branch: str, changed_files: Optional[List[str]] = None) -> Dict[str, Any]:
        """
        执行代码扫描（实现抽象方法）

        Args:
            repo_url: 仓库 URL
            commit_id: 提交 ID
            branch: 分支名
            changed_files: 可选的变更文件列表（来自 PR）

        Returns:
            审查结果
        """
        # 调用实际的审查逻辑
        return self._do_review(repo_url=repo_url, commit_id=commit_id, branch=branch, changed_files=changed_files)

    def _do_review(self, clone_dir: str = None, repo_url: str = None,
                   commit_id: str = None, branch: str = None,
                   language: str = 'python',
                   changed_files: Optional[List[str]] = None) -> Dict[str, Any]:
        """
        执行 AI 代码审查

        Args:
            clone_dir: 仓库目录（如果已克隆则直接传入）
            repo_url: 仓库 URL（如果未克隆则需要传入）
            commit_id: 提交 ID
            branch: 分支名
            language: 编程语言
            changed_files: 可选的变更文件列表（来自 PR）

        Returns:
            审查结果（与 python_scanner.py 兼容的格式）
        """
        result = {
            'tool': 'AI Code Reviewer',
            'language': language,
            'status': 'success',
            'issues': [],
            'summary': {
                'total': 0,
                'error': 0,
                'warning': 0,
                'info': 0
            },
            'files_scanned': 0
        }

        if not self.enabled:
            result['status'] = 'disabled'
            result['summary'] = 'AI 审查已禁用'
            return result

        try:
            # 如果没有传入 clone_dir，需要克隆
            if not clone_dir and repo_url:
                clone_dir = self.clone_repo(repo_url, commit_id, branch)

            if not clone_dir or not os.path.exists(clone_dir):
                result['status'] = 'error'
                result['error'] = '无法获取代码目录'
                return result

            # 获取要审查的代码文件
            files = self._get_code_files(clone_dir, language, changed_files)

            if not files:
                result['summary'] = '未找到可审查的代码文件'
                return result

            # 对每个文件进行 AI 审查
            all_issues = []
            for file_path in files[:5]:  # 限制最多审查 5 个文件
                review = self._review_file(file_path, language, clone_dir)
                if review and review.get('issues'):
                    all_issues.extend(review['issues'])

            result['issues'] = all_issues[:self.max_issues] if self.detailed else all_issues
            result['summary'] = self._calculate_summary(all_issues)
            result['files_scanned'] = len(files[:5])
            result['clone_dir'] = clone_dir

            # 生成质量评分
            result['quality_score'] = self._calculate_quality_score(all_issues, files[:5])

            return result

        except Exception as e:
            logger.error(f'AI 审查失败: {str(e)}')
            result['status'] = 'error'
            result['error'] = str(e)
            return result

    def _calculate_summary(self, issues: List[Dict]) -> Dict[str, int]:
        """计算问题摘要"""
        summary = {
            'total': len(issues),
            'error': 0,
            'warning': 0,
            'info': 0
        }

        for issue in issues:
            severity = issue.get('severity', '').lower()
            if severity in ['error', 'critical', 'fatal']:
                summary['error'] += 1
            elif severity in ['warning', 'moderate']:
                summary['warning'] += 1
            else:
                summary['info'] += 1

        return summary

    def _calculate_quality_score(self, issues: List[Dict], files: List[str]) -> Dict[str, Any]:
        """
        计算代码质量评分
        返回：总分(0-100)及各维度评分
        """
        if not files:
            return {'total': 100, 'maintainability': 100, 'security': 100, 'readability': 100, 'best_practices': 100}

        # 统计问题
        error_count = sum(1 for i in issues if i.get('severity', '').lower() in ['error', 'critical'])
        warning_count = sum(1 for i in issues if i.get('severity', '').lower() == 'warning')
        info_count = sum(1 for i in issues if i.get('severity', '').lower() == 'info')

        # 分类统计
        security_keywords = ['sql injection', 'xss', 'csrf', 'password', 'secret', 'token', '权限', '注入', '认证']
        security_issues = sum(1 for i in issues if any(k in (i.get('message', '') + i.get('symbol', '')).lower() for k in security_keywords))

        # 计算各维度分数
        # 可维护性：基于错误和警告数量
        issue_weight = error_count * 5 + warning_count * 2 + info_count * 0.5
        maintainability = max(0, 100 - issue_weight)

        # 安全性：基于安全问题
        security_score = max(0, 100 - security_issues * 15)

        # 可读性：基于 info 级别问题（风格类）
        readability = max(0, 100 - info_count * 3)

        # 最佳实践：基于 warning 级别
        best_practices = max(0, 100 - warning_count * 5)

        # 总分：加权平均
        total = int((maintainability * 0.3 + security_score * 0.35 + readability * 0.15 + best_practices * 0.2))

        return {
            'total': total,
            'maintainability': maintainability,
            'security': security_score,
            'readability': readability,
            'best_practices': best_practices,
            'details': {
                'error_count': error_count,
                'warning_count': warning_count,
                'info_count': info_count,
                'security_issues': security_issues
            }
        }

    def generate_fix_suggestion(self, file_path: str, line: int, message: str, code: str) -> Optional[str]:
        """
        对指定问题生成修复建议代码
        """
        prompt = f"""你是一位代码修复专家。请根据以下问题，生成修复后的代码。

问题描述：{message}
问题所在行号：{line}

原始代码：
```
{code}
```

请以 JSON 格式输出修复建议：
```json
{{
  "fixed_code": "修复后的完整代码或关键片段",
  "explanation": "修复说明（50字以内）",
  "confidence": "high/medium/low 修复把握度"
}}
```

如果无法修复，请返回：{{"fixed_code": "", "explanation": "无法自动修复", "confidence": "low"}}"""

        try:
            response = self._call_ai(prompt)
            if response and response.get('fixed_code'):
                return response
        except Exception as e:
            logger.warning(f'生成修复建议失败: {e}')

        return None

    def _get_code_files(self, clone_dir: str, language: str, changed_files: Optional[List[str]] = None) -> List[str]:
        """获取代码文件列表"""
        import glob

        extensions = {
            'python': ['.py'],
            'javascript': ['.js', '.jsx'],
            'typescript': ['.ts', '.tsx']
        }

        exts = extensions.get(language, ['.py'])

        # 如果提供了变更文件列表，只返回这些文件
        if changed_files:
            files = []
            for changed_file in changed_files:
                if any(changed_file.endswith(ext) for ext in exts):
                    full_path = os.path.join(clone_dir, changed_file)
                    if os.path.exists(full_path):
                        files.append(full_path)
            return files[:10]

        # 否则扫描整个仓库
        files = []

        for ext in exts:
            pattern = os.path.join(clone_dir, '**', f'*{ext}')
            files.extend(glob.glob(pattern, recursive=True))

        # 过滤掉测试文件和虚拟环境
        files = [f for f in files if not any(x in f for x in [
            'test_', '_test.', 'venv', 'node_modules', '__pycache__'
        ])]

        return files[:10]  # 最多 10 个文件

    def _review_file(self, file_path: str, language: str, clone_dir: str = None) -> Optional[Dict[str, Any]]:
        """审查单个文件"""
        issues = []
        
        try:
            with open(file_path, 'r', encoding='utf-8') as f:
                code = f.read()

            # 限制代码行数
            lines = code.split('\n')
            if len(lines) > self.max_lines:
                code = '\n'.join(lines[:self.max_lines])
                truncated = True
            else:
                truncated = False

            # 给代码加行号再发给模型，便于模型返回准确行号
            code_with_lines = self._code_with_line_numbers(code)
            prompt = self._build_prompt(code_with_lines, language)

            # 调用 AI
            response = self._call_ai(prompt)

            # 获取相对路径
            rel_path = os.path.relpath(file_path, clone_dir) if (clone_dir and file_path) else file_path

            if not response:
                return {
                    'file': rel_path,
                    'path': file_path,
                    'truncated': truncated,
                    'issues': []
                }

            # 解析 AI 响应，转换为标准 issues 格式，并校正行号
            ai_issues = response.get('issues', [])
            for issue in ai_issues:
                self._correct_issue_line(issue, code)
                issues.append({
                    'tool': 'ai_reviewer',
                    'type': issue.get('type', 'info'),
                    'severity': issue.get('severity', 'Info'),
                    'message': issue.get('message', ''),
                    'file': rel_path,
                    'line': issue.get('line', 0),
                    'column': issue.get('column', 0),
                    'symbol': issue.get('symbol', ''),
                    'code_context': issue.get('code_context', ''),
                    'defect_reason': issue.get('defect_reason', '')
                })

            return {
                'file': rel_path,
                'path': file_path,
                'truncated': truncated,
                'issues': issues
            }

        except Exception as e:
            logger.warning(f'审查文件失败 {file_path}: {str(e)}')
            return None

    def _build_prompt(self, code: str, language: str) -> str:
        """构建审查 prompt"""
        if language == 'python':
            lang_name = 'Python'
        elif language in ['javascript', 'typescript']:
            lang_name = 'JavaScript/TypeScript'
        else:
            lang_name = language

        prompt = f"""你是一位资深的 {lang_name} 代码审查专家。请审查以下代码，找出潜在的问题和缺陷。

请以 JSON 格式输出审查结果，必须包含以下字段：
```json
{{
  "issues": [
    {{
      "line": 行号,
      "column": 列号,
      "message": "问题描述",
      "type": "error/warning/info 之一",
      "severity": "Error/Warning/Info 之一",
      "symbol": "错误标识符如 unused-variable, syntax-error 等",
      "code_context": "问题代码的上下文（包含问题的那行或几行代码）",
      "defect_reason": "缺陷原因分析（30字以内简洁描述）"
    }}
  ]
}}
```

注意：
1. line 和 column 是问题所在的行号和列号（从 1 开始）
2. type: error=错误, warning=警告, info=信息
3. severity: Error=严重, Warning=一般, Info=提示
4. code_context: 包含问题代码的那一行或相邻的几行
5. defect_reason: 精简描述，30字以内，说明问题原因和风险

如果代码没有问题，返回空数组: {{"issues": []}}

重要：以下代码每行前已标注行号（格式为 "行号|"），请根据问题实际出现的代码行，严格使用该行前的行号填写 issues 中的 line 字段，不要猜测或使用错误行号。

以下是待审查的代码（行号已标注）：
```{language}
{code}
```"""
        return prompt

    def _code_with_line_numbers(self, code: str) -> str:
        """给代码每行前加上行号，便于模型返回准确行号"""
        lines = code.split('\n')
        width = len(str(len(lines)))
        return '\n'.join(f'{i:>{width}}| {line}' for i, line in enumerate(lines, 1))

    def _correct_issue_line(self, issue: Dict[str, Any], code: str) -> None:
        """
        根据 message/symbol 在源码中搜索，尽量把 issue 的 line 校正到真实出现位置。
        AI 返回的行号常不准确，通过匹配问题相关的标识符（如 'unused_module'）修正行号。
        """
        line = issue.get('line')
        if not line or not code:
            return
        lines = code.split('\n')
        if line < 1 or line > len(lines):
            return

        # 从 message 中提取被引用的标识符（如 'unused_module' -> unused_module）
        message = (issue.get('message') or '')
        symbol = (issue.get('symbol') or '').strip()
        candidates = []
        if symbol:
            candidates.append(symbol)
        for m in re.finditer(r"['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]", message or ''):
            candidates.append(m.group(1))
        # 若 message 里没有引号标识符，取首段英文/数字/下划线作为关键词
        if not candidates:
            first_word = re.search(r'\b([a-zA-Z_][a-zA-Z0-9_]*)\b', message)
            if first_word:
                candidates.append(first_word.group(1))

        for token in candidates:
            if not token:
                continue
            for i, code_line in enumerate(lines):
                if token in code_line:
                    issue['line'] = i + 1
                    return

    def _call_ai(self, prompt: str) -> Optional[Dict[str, Any]]:
        """调用 AI 服务"""
        try:
            return self._call_api(prompt)
        except Exception as e:
            print("异常追踪信息:", e.__traceback__)
            logger.error(f'AI 调用失败: {str(e)}')
            return None

    def _extract_json_obj(self, content: Any) -> Optional[Dict[str, Any]]:
        """
        从模型输出中尽可能提取 JSON 对象(dict)。

        兼容场景：
        - content 已经是 dict
        - content 是 JSON 字符串
        - content 被 ```json ... ``` 或 ``` ... ``` 包裹
        - content 前后夹杂说明文字，只要包含一个最外层 { ... } 就尝试解析
        """
        if content is None:
            logger.debug("_extract_json_obj: content is None")
            return None

        # 如果已经是 dict，直接返回
        if isinstance(content, dict):
            logger.debug("_extract_json_obj: content is already dict")
            return content

        if not isinstance(content, str):
            content = str(content)

        text = content.strip()
        logger.debug(f"_extract_json_obj: 原始内容长度 = {len(text)}")
        logger.debug(f"_extract_json_obj: 原始内容前100字符: {text[:100]}")

        # 去掉代码块包裹（兼容 ```json / ``` json / ```JSON 等）
        lowered = text.lower()
        fence_start = lowered.find('```')
        if fence_start != -1:
            logger.debug(f"_extract_json_obj: 发现代码块 fence_start={fence_start}")
            # 找到第一段 fence
            after = text[fence_start + 3:]
            after_l = after.lower()
            # 如果 fence 后紧跟语言标识（json 或其他），跳过这一行直到换行
            newline_idx = after.find('\n')
            if newline_idx != -1:
                lang_header = after_l[:newline_idx].strip()
                logger.debug(f"_extract_json_obj: 语言标识: {lang_header}")
                body = after[newline_idx + 1:]
                # 截取到下一个 fence 结束
                end_idx = body.lower().find('```')
                if end_idx != -1:
                    candidate = body[:end_idx].strip()
                else:
                    # 没有结束 fence，直接用 body 作为候选（可能是截断的 JSON）
                    candidate = body.strip()
                # 只有在确实像 json 的情况下才替换，避免误伤普通文本
                if '{' in candidate and '}' in candidate:
                    text = candidate
                    logger.debug(f"_extract_json_obj: 提取代码块内容成功，长度={len(text)}")
            else:
                # 没有换行就按旧逻辑尽量截取
                pass

        # 直接解析
        try:
            obj = json.loads(text)
            logger.debug("_extract_json_obj: 直接解析成功")
            return obj if isinstance(obj, dict) else None
        except Exception as e:
            logger.debug(f"_extract_json_obj: 直接解析失败: {e}")

        # 兜底：截取最外层 { ... } 再解析
        start = text.find('{')
        end = text.rfind('}')
        logger.debug(f"_extract_json_obj: 查找大括号 start={start}, end={end}")
        if start != -1 and end != -1 and end > start:
            candidate = text[start:end + 1].strip()
            logger.debug(f"_extract_json_obj: 候选内容长度={len(candidate)}, 前50字符: {candidate[:50]}")
            try:
                obj = json.loads(candidate)
                logger.debug("_extract_json_obj: 兜底解析成功")
                return obj if isinstance(obj, dict) else None
            except Exception as e:
                logger.debug(f"_extract_json_obj: 兜底解析失败: {e}")
                return None

        logger.debug("_extract_json_obj: 未能提取到有效的 JSON 对象")
        return None

    def _call_api(self, prompt: str) -> Optional[Dict[str, Any]]:
        """调用在线 API"""
        import requests

        headers = {
            'Content-Type': 'application/json'
        }

        if self.api_key:
            headers['Authorization'] = f'Bearer {self.api_key}'

        # 根据 API URL 自动判断 provider
        if 'siliconflow' in self.api_url:
            url = f"{self.api_url}/chat/completions"
            payload = {
                "model": self.model,
                "messages": [{"role": "user", "content": prompt}],
                "max_tokens": 1024,
                "temperature": 0.7
            }
        elif 'deepseek' in self.api_url:
            url = f"{self.api_url}/chat/completions"
            payload = {
                "model": self.model,
                "messages": [{"role": "user", "content": prompt}],
                "max_tokens": 1024,
                "temperature": 0.7
            }
        elif 'dashscope' in self.api_url:
            # 阿里云 dashscope 专用端点
            url = f"{self.api_url}/chat/completions"
            payload = {
                "model": self.model,
                "messages": [{"role": "user", "content": prompt}],
                "max_tokens": 1024,
                "temperature": 0.7,
                "stream": False  # 显式关闭流式
            }
        else:
            url = f"{self.api_url}/chat/completions"
            payload = {
                "model": self.model,
                "messages": [{"role": "user", "content": prompt}],
                "max_tokens": 1024,
                "temperature": 0.7
            }

        logger.info(f"调用 API: {url}, model={self.model}")

        try:
            response = requests.post(url, json=payload, headers=headers, timeout=120)

            if response.status_code == 200:
                result = response.json()
                content = result['choices'][0]['message']['content']
                logger.info(f"API 返回内容长度: {len(content) if content else 0}")
                parsed = self._extract_json_obj(content)
                return parsed

            logger.warning(f'API 返回错误: {response.status_code}, {response.text[:200]}')
            return None

        except Exception as e:
            logger.warning(f'API 调用失败: {e}')
            return None