"""
输入验证工具
"""
import re
from typing import Optional

def validate_question(question: str) -> Optional[str]:
    """验证用户问题"""
    if not question:
        return "问题不能为空"
    
    if len(question) < 5:
        return "问题太短，请提供更详细的描述"
    
    if len(question) > 1000:
        return "问题太长，请精简到1000字以内"
    
    # 检查是否包含有效内容（不只是标点符号）
    if not re.search(r'[a-zA-Z\u4e00-\u9fa5]+', question):
        return "请输入有效的问题内容"
    
    return None

def validate_outline_feedback(feedback: str) -> Optional[str]:
    """验证大纲反馈"""
    if not feedback:
        return "反馈内容不能为空"
    
    if len(feedback) < 10:
        return "请提供更详细的修改建议"
    
    if len(feedback) > 500:
        return "反馈内容请控制在500字以内"
    
    return None

def validate_session_id(session_id: str) -> Optional[str]:
    """验证会话ID"""
    if not session_id:
        return "会话ID不能为空"
    
    # UUID格式验证
    uuid_pattern = re.compile(
        r'^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$',
        re.IGNORECASE
    )
    
    if not uuid_pattern.match(session_id):
        return "无效的会话ID格式"
    
    return None

def validate_subtopic_id(subtopic_id: str) -> Optional[str]:
    """验证子主题ID"""
    if not subtopic_id:
        return "子主题ID不能为空"
    
    # 格式: ST开头 + 8位十六进制
    if not re.match(r'^ST[0-9a-f]{8}$', subtopic_id, re.IGNORECASE):
        return "无效的子主题ID格式"
    
    return None

def validate_search_query(query: str) -> Optional[str]:
    """验证搜索查询"""
    if not query:
        return "搜索查询不能为空"
    
    if len(query) < 2:
        return "搜索查询太短"
    
    if len(query) > 200:
        return "搜索查询太长，请控制在200字符以内"
    
    # 检查是否包含特殊字符攻击
    dangerous_patterns = [
        r'<script',
        r'javascript:',
        r'onerror=',
        r'onclick=',
        r'DROP TABLE',
        r'DELETE FROM',
        r'INSERT INTO'
    ]
    
    for pattern in dangerous_patterns:
        if re.search(pattern, query, re.IGNORECASE):
            return "搜索查询包含不允许的内容"
    
    return None

def validate_priority(priority: str) -> Optional[str]:
    """验证优先级"""
    valid_priorities = ['high', 'medium', 'low']
    
    if priority not in valid_priorities:
        return f"优先级必须是以下之一: {', '.join(valid_priorities)}"
    
    return None

def validate_report_format(format: str) -> Optional[str]:
    """验证报告格式"""
    valid_formats = ['json', 'markdown', 'html', 'pdf']
    
    if format not in valid_formats:
        return f"报告格式必须是以下之一: {', '.join(valid_formats)}"
    
    return None

def sanitize_filename(filename: str) -> str:
    """清理文件名"""
    # 移除不安全的字符
    filename = re.sub(r'[<>:"/\\|?*]', '_', filename)
    
    # 限制长度
    if len(filename) > 200:
        filename = filename[:200]
    
    # 确保不以点开头（隐藏文件）
    if filename.startswith('.'):
        filename = '_' + filename[1:]
    
    return filename

def validate_json_structure(data: dict, required_fields: list) -> Optional[str]:
    """验证JSON结构"""
    for field in required_fields:
        if field not in data:
            return f"缺少必要字段: {field}"
    
    return None