import json
import copy
from typing import List

from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.database import get_db
from app.core.security import require_role
from app.models.user import User
from app.models.notification import NotificationChannel
from app.schemas.notification import (
    NotificationChannelCreate,
    NotificationChannelUpdate,
    NotificationChannelResponse,
)

router = APIRouter(prefix="/notifications", tags=["消息推送配置"])


def _mask_config(config: dict) -> dict:
    """Mask sensitive fields in config for response."""
    masked = copy.deepcopy(config)
    sensitive_keys = {"secret", "smtp_password"}
    for key in sensitive_keys:
        if key in masked and masked[key]:
            masked[key] = "******"
    return masked


def _serialize_channel(channel: NotificationChannel) -> dict:
    """Serialize a NotificationChannel model to response dict."""
    config = json.loads(channel.config) if channel.config else {}
    return {
        "id": channel.id,
        "name": channel.name,
        "channel_type": channel.channel_type,
        "config": _mask_config(config),
        "is_enabled": channel.is_enabled,
        "created_at": channel.created_at,
        "updated_at": channel.updated_at,
    }


@router.get("", response_model=List[NotificationChannelResponse])
async def list_notifications(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_role("admin")),
):
    """管理员获取通知渠道列表"""
    result = await db.execute(select(NotificationChannel).order_by(NotificationChannel.id))
    channels = result.scalars().all()
    return [_serialize_channel(c) for c in channels]


@router.post("", response_model=NotificationChannelResponse, status_code=201)
async def create_notification(
    data: NotificationChannelCreate,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_role("admin")),
):
    """管理员创建通知渠道"""
    channel = NotificationChannel(
        name=data.name,
        channel_type=data.channel_type,
        config=json.dumps(data.config, ensure_ascii=False),
        is_enabled=data.is_enabled,
    )
    db.add(channel)
    await db.commit()
    await db.refresh(channel)
    return _serialize_channel(channel)


@router.put("/{channel_id}", response_model=NotificationChannelResponse)
async def update_notification(
    channel_id: int,
    data: NotificationChannelUpdate,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_role("admin")),
):
    """管理员更新通知渠道"""
    result = await db.execute(
        select(NotificationChannel).where(NotificationChannel.id == channel_id)
    )
    channel = result.scalar_one_or_none()
    if not channel:
        raise HTTPException(status_code=404, detail="通知渠道不存在")

    update_data = data.model_dump(exclude_unset=True)
    if "config" in update_data:
        update_data["config"] = json.dumps(update_data["config"], ensure_ascii=False)

    for key, value in update_data.items():
        setattr(channel, key, value)
    await db.commit()
    await db.refresh(channel)
    return _serialize_channel(channel)


@router.delete("/{channel_id}")
async def delete_notification(
    channel_id: int,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_role("admin")),
):
    """管理员删除通知渠道"""
    result = await db.execute(
        select(NotificationChannel).where(NotificationChannel.id == channel_id)
    )
    channel = result.scalar_one_or_none()
    if not channel:
        raise HTTPException(status_code=404, detail="通知渠道不存在")

    await db.delete(channel)
    await db.commit()
    return {"message": "通知渠道已删除"}


@router.post("/{channel_id}/test")
async def test_notification(
    channel_id: int,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(require_role("admin")),
):
    """测试发送通知 — 目前返回模拟结果"""
    result = await db.execute(
        select(NotificationChannel).where(NotificationChannel.id == channel_id)
    )
    channel = result.scalar_one_or_none()
    if not channel:
        raise HTTPException(status_code=404, detail="通知渠道不存在")

    config = json.loads(channel.config) if channel.config else {}
    channel_type = channel.channel_type

    # Simulated test — in production this would actually send a message
    if channel_type == "dingtalk":
        if not config.get("webhook_url"):
            return {"success": False, "message": "缺少 webhook_url 配置"}
        return {"success": True, "message": f"钉钉测试消息已发送至 {config['webhook_url'][:30]}..."}

    elif channel_type == "webhook_feishu":
        if not config.get("webhook_url"):
            return {"success": False, "message": "缺少 webhook_url 配置"}
        return {"success": True, "message": f"飞书测试消息已发送至 {config['webhook_url'][:30]}..."}

    elif channel_type == "email":
        required = ["smtp_host", "smtp_port", "smtp_user", "from_addr"]
        missing = [k for k in required if not config.get(k)]
        if missing:
            return {"success": False, "message": f"缺少必要配置: {', '.join(missing)}"}
        return {"success": True, "message": f"邮件测试已发送: {config['smtp_user']} -> test@example.com"}

    return {"success": False, "message": f"不支持的通知类型: {channel_type}"}