"""文件编辑工具"""

from pathlib import Path
from typing import Optional, Type

from anyio import Path as AsyncPath
from pydantic import BaseModel, Field

from app.agent.tools.base import MoviePilotTool
from app.log import logger


class EditFileInput(BaseModel):
    """Input parameters for edit file tool"""
    file_path: str = Field(..., description="The absolute path of the file to edit")
    old_text: str = Field(..., description="The exact old text to be replaced")
    new_text: str = Field(..., description="The new text to replace with")


class EditFileTool(MoviePilotTool):
    name: str = "edit_file"
    description: str = "Edit a file by replacing specific old text with new text. Useful for modifying configuration files, code, or scripts."
    args_schema: Type[BaseModel] = EditFileInput

    def get_tool_message(self, **kwargs) -> Optional[str]:
        """根据参数生成友好的提示消息"""
        file_path = kwargs.get("file_path", "")
        file_name = Path(file_path).name if file_path else "未知文件"
        return f"正在编辑文件: {file_name}"

    async def run(self, file_path: str, old_text: str, new_text: str, **kwargs) -> str:
        logger.info(f"执行工具: {self.name}, 参数: file_path={file_path}")

        try:
            path = AsyncPath(file_path)
            # 校验逻辑：如果要替换特定文本，文件必须存在且包含该文本
            if not await path.exists():
                # 如果 old_text 为空，可能用户想直接创建文件，但通常 edit_file 需要匹配旧内容
                if old_text:
                    return f"错误：文件 {file_path} 不存在，无法进行内容替换。"
                
            if await path.exists() and not await path.is_file():
                return f"错误：{file_path} 不是一个文件"

            if await path.exists():
                content = await path.read_text(encoding="utf-8")
                if old_text not in content:
                    logger.warning(f"编辑文件 {file_path} 失败：未找到指定的旧文本块")
                    return f"错误：在文件 {file_path} 中未找到指定的旧文本。请确保包含所有的空格、缩进 and 换行符。"
                occurrences = content.count(old_text)
                new_content = content.replace(old_text, new_text)
            else:
                # 文件不存在且 old_text 为空的情形（初始化新文件）
                new_content = new_text
                occurrences = 1

            # 自动创建父目录
            await path.parent.mkdir(parents=True, exist_ok=True)
            
            # 写入文件
            await path.write_text(new_content, encoding="utf-8")
                
            logger.info(f"成功编辑文件 {file_path}，替换了 {occurrences} 处内容")
            return f"成功编辑文件 {file_path} (替换了 {occurrences} 处匹配内容)"


        except PermissionError:
            return f"错误：没有访问/修改 {file_path} 的权限"
        except UnicodeDecodeError:
            return f"错误：{file_path} 不是文本文件，无法编辑"
        except Exception as e:
            logger.error(f"编辑文件 {file_path} 时发生错误: {str(e)}", exc_info=True)
            return f"操作失败: {str(e)}"