from fastapi import APIRouter, HTTPException, Depends
from app.core.auth import get_current_admin_user
from app.core.config import LLM_CONFIG, DEFAULT_RESET_PASSWORD, MAX_FILE_SIZE, MAX_IMAGE_SIZE
from pydantic import BaseModel
import os
import json
from pathlib import Path

router = APIRouter()

# 配置文件路径
CONFIG_FILE = Path(__file__).parent.parent.parent.parent / "config" / "system_config.json"

class SystemConfigModel(BaseModel):
    model_name: str
    system_prompt: str
    DEFAULT_RESET_PASSWORD: str
    MAX_FILE_SIZE: int  # 字节为单位
    MAX_IMAGE_SIZE: int  # 字节为单位

class SystemConfigResponse(BaseModel):
    model_name: str
    system_prompt: str
    DEFAULT_RESET_PASSWORD: str
    MAX_FILE_SIZE: int
    MAX_IMAGE_SIZE: int
    message: str = ""

def load_config_from_file():
    """从文件加载配置，如果文件不存在则返回默认配置"""
    try:
        if CONFIG_FILE.exists():
            with open(CONFIG_FILE, 'r', encoding='utf-8') as f:
                return json.load(f)
    except Exception:
        pass

    # 返回默认配置
    return {
        'model_name': LLM_CONFIG['model_name'],
        'system_prompt': LLM_CONFIG['system_prompt'],
        'DEFAULT_RESET_PASSWORD': DEFAULT_RESET_PASSWORD,
        'MAX_FILE_SIZE': MAX_FILE_SIZE,
        'MAX_IMAGE_SIZE': MAX_IMAGE_SIZE
    }

def save_config_to_file(config_data):
    """将配置保存到文件"""
    try:
        # 确保配置目录存在
        CONFIG_FILE.parent.mkdir(parents=True, exist_ok=True)

        with open(CONFIG_FILE, 'w', encoding='utf-8') as f:
            json.dump(config_data, f, ensure_ascii=False, indent=2)
        return True
    except Exception as e:
        print(f"保存配置文件失败: {e}")
        return False

@router.get("/admin/system-config", response_model=SystemConfigResponse)
async def get_system_config(current_user=Depends(get_current_admin_user)):
    """
    获取系统配置
    只有管理员才能访问
    """
    try:
        # 优先从文件加载配置，然后从内存配置补充
        config = load_config_from_file()

        return SystemConfigResponse(
            model_name=config.get('model_name', LLM_CONFIG['model_name']),
            system_prompt=config.get('system_prompt', LLM_CONFIG['system_prompt']),
            DEFAULT_RESET_PASSWORD=config.get('DEFAULT_RESET_PASSWORD', DEFAULT_RESET_PASSWORD),
            MAX_FILE_SIZE=config.get('MAX_FILE_SIZE', MAX_FILE_SIZE),
            MAX_IMAGE_SIZE=config.get('MAX_IMAGE_SIZE', MAX_IMAGE_SIZE),
            message="配置获取成功"
        )
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"获取配置失败: {str(e)}")

@router.put("/admin/system-config", response_model=SystemConfigResponse)
async def update_system_config(
    config: SystemConfigModel,
    current_user=Depends(get_current_admin_user)
):
    """
    更新系统配置
    只有管理员才能访问
    """
    try:
        # 准备要保存的配置数据
        config_data = {
            'model_name': config.model_name,
            'system_prompt': config.system_prompt,
            'DEFAULT_RESET_PASSWORD': config.DEFAULT_RESET_PASSWORD,
            'MAX_FILE_SIZE': config.MAX_FILE_SIZE,
            'MAX_IMAGE_SIZE': config.MAX_IMAGE_SIZE
        }

        # 保存到文件
        if not save_config_to_file(config_data):
            raise HTTPException(status_code=500, detail="配置保存到文件失败")

        # 更新运行时配置
        LLM_CONFIG['model_name'] = config.model_name
        LLM_CONFIG['system_prompt'] = config.system_prompt

        # 更新模块级别的配置
        import app.core.config as config_module
        config_module.DEFAULT_RESET_PASSWORD = config.DEFAULT_RESET_PASSWORD
        config_module.MAX_FILE_SIZE = config.MAX_FILE_SIZE
        config_module.MAX_IMAGE_SIZE = config.MAX_IMAGE_SIZE

        return SystemConfigResponse(
            model_name=config.model_name,
            system_prompt=config.system_prompt,
            DEFAULT_RESET_PASSWORD=config.DEFAULT_RESET_PASSWORD,
            MAX_FILE_SIZE=config.MAX_FILE_SIZE,
            MAX_IMAGE_SIZE=config.MAX_IMAGE_SIZE,
            message="配置更新成功，重启服务后完全生效"
        )
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"更新配置失败: {str(e)}")

# 在应用启动时加载配置
def load_system_config():
    """在应用启动时调用，加载保存的配置"""
    try:
        config = load_config_from_file()

        # 更新运行时配置
        LLM_CONFIG['model_name'] = config.get('model_name', LLM_CONFIG['model_name'])
        LLM_CONFIG['system_prompt'] = config.get('system_prompt', LLM_CONFIG['system_prompt'])

        # 更新其他配置
        import app.core.config as config_module
        config_module.DEFAULT_RESET_PASSWORD = config.get('DEFAULT_RESET_PASSWORD', DEFAULT_RESET_PASSWORD)
        config_module.MAX_FILE_SIZE = config.get('MAX_FILE_SIZE', MAX_FILE_SIZE)
        config_module.MAX_IMAGE_SIZE = config.get('MAX_IMAGE_SIZE', MAX_IMAGE_SIZE)

        print(f"系统配置加载成功: model={config.get('model_name')}")
    except Exception as e:
        print(f"加载系统配置失败，使用默认配置: {e}")