"""services 路由：MCP 服务注册 + per-service API Key 管理"""

import hashlib
import secrets

from fastapi import APIRouter, Depends, HTTPException, Query, status
from pydantic import BaseModel

from ..core.db import get_pool
from ..core.deps import current_admin
from ..core.redis import cache_delete

router = APIRouter(prefix="/api/services", tags=["services"])


class ServiceCreate(BaseModel):
    service_name: str          # erp / crm / ...
    service_url: str           # MCP 服务地址（如 http://10.100.154.100:8001/mcp）
    description: str | None = None


def _row_to_dict(row) -> dict:
    return {
        "service_id": row["service_id"],
        "service_name": row["service_name"],
        "service_url": row["service_url"],
        "api_key": row["api_key"],
        "description": row["description"],
        "status": row["status"],
        "created_at": row["created_at"].isoformat() if row["created_at"] else None,
        "created_by": row["created_by"],
        "revoked_at": row["revoked_at"].isoformat() if row["revoked_at"] else None,
        "last_used_at": row["last_used_at"].isoformat() if row["last_used_at"] else None,
    }


@router.get("")
async def list_services(
    status_filter: str | None = Query(None, alias="status"),
    admin: dict = Depends(current_admin),
):
    pool = await get_pool()
    query = "SELECT * FROM mcp_service WHERE 1=1"
    params: list = []
    if status_filter:
        query += f" AND status = ${len(params)+1}"
        params.append(status_filter)
    query += " ORDER BY service_id DESC"
    rows = await pool.fetch(query, *params)
    return {"total": len(rows), "services": [_row_to_dict(r) for r in rows]}


@router.post("", status_code=status.HTTP_201_CREATED)
async def register_service(req: ServiceCreate, admin: dict = Depends(current_admin)):
    pool = await get_pool()

    # 检查是否已存在同名 active 服务
    existing = await pool.fetchrow(
        "SELECT service_id FROM mcp_service WHERE service_name = $1 AND status = 'active'",
        req.service_name,
    )
    if existing:
        raise HTTPException(400, f"服务 {req.service_name} 已存在且处于 active 状态")

    # MCP 服务地址唯一性校验
    url_existing = await pool.fetchval(
        "SELECT 1 FROM mcp_service WHERE service_url = $1",
        req.service_url.strip(),
    )
    if url_existing:
        raise HTTPException(400, f"MCP 服务地址 {req.service_url} 已被其他服务使用")

    # 生成 API Key
    plain = secrets.token_urlsafe(32)
    api_key_hash = hashlib.sha256(plain.encode()).hexdigest()

    row = await pool.fetchrow(
        """INSERT INTO mcp_service (service_name, service_url, api_key, api_key_hash, description, created_by)
           VALUES ($1, $2, $3, $4, $5, $6)
           RETURNING service_id, service_name, service_url, api_key, description, created_at, created_by""",
        req.service_name, req.service_url.strip(), plain, api_key_hash, req.description, admin.get("username", "admin"),
    )

    return {
        "api_key": plain,
        "service_id": row["service_id"],
        "service_name": row["service_name"],
        "message": "请保存此 API Key，配置到 MCP 服务的 MCP_AUTH_API_KEY 环境变量",
    }


@router.patch("/{service_id}/revoke")
async def revoke_service(
    service_id: int,
    admin: dict = Depends(current_admin),
):
    pool = await get_pool()
    row = await pool.fetchrow(
        "SELECT service_id, status, api_key_hash FROM mcp_service WHERE service_id = $1", service_id
    )
    if row is None:
        raise HTTPException(404, "服务不存在")
    if row["status"] == "revoked":
        raise HTTPException(400, "服务已吊销")

    await pool.execute(
        "UPDATE mcp_service SET status = 'revoked', revoked_at = NOW() WHERE service_id = $1",
        service_id,
    )
    await cache_delete(f"mcp:svc:{row['api_key_hash']}")
    return {"success": True, "service_id": service_id, "status": "revoked"}


@router.patch("/{service_id}/enable")
async def enable_service(
    service_id: int,
    admin: dict = Depends(current_admin),
):
    """启用服务：将已吊销的服务恢复为 active。"""
    pool = await get_pool()
    row = await pool.fetchrow(
        "SELECT service_id, status, api_key_hash FROM mcp_service WHERE service_id = $1", service_id
    )
    if row is None:
        raise HTTPException(404, "服务不存在")
    if row["status"] == "active":
        raise HTTPException(400, "服务已是启用状态")

    await pool.execute(
        "UPDATE mcp_service SET status = 'active', revoked_at = NULL WHERE service_id = $1",
        service_id,
    )
    await cache_delete(f"mcp:svc:{row['api_key_hash']}")
    return {"success": True, "service_id": service_id, "status": "active"}


@router.delete("/{service_id}")
async def delete_service(
    service_id: int,
    admin: dict = Depends(current_admin),
):
    pool = await get_pool()
    row = await pool.fetchrow(
        "SELECT service_id, status, api_key_hash FROM mcp_service WHERE service_id = $1", service_id
    )
    if row is None:
        raise HTTPException(404, "服务不存在")
    if row["status"] != "revoked":
        raise HTTPException(400, "仅允许删除已吊销的服务，请先调用吊销端点")

    await pool.execute("DELETE FROM mcp_service WHERE service_id = $1", service_id)
    await cache_delete(f"mcp:svc:{row['api_key_hash']}")
    return {"success": True, "service_id": service_id}