import {
  Body,
  Controller,
  Get,
  HttpException,
  HttpStatus,
  Param,
  Post,
  Put,
  Query,
  Req,
} from "@nestjs/common";
import { NotificationsService } from "./notifications.service.js";
import type { SendNotificationDto } from "./notifications.service.js";

interface AuthedRequest {
  headers: Record<string, string | string[] | undefined>;
}

/**
 * 从请求头读取用户身份。
 * Gateway 在通过鉴权后会注入 x-user-id；如未注入（开发模式或匿名请求）返回 null。
 */
function getUserIdFromRequest(req: AuthedRequest): string | null {
  const raw = req.headers["x-user-id"];
  if (typeof raw === "string" && raw.length > 0) return raw;
  return null;
}

@Controller("notifications")
export class NotificationsController {
  constructor(private readonly service: NotificationsService) {}

  @Post()
  async send(@Body() body: unknown): Promise<{ success: true; data: unknown }> {
    const result = await this.service.send(body as SendNotificationDto);
    return { success: true, data: result };
  }

  @Post("batch")
  async createBatch(
    @Body() body: unknown,
  ): Promise<{ success: true; data: unknown }> {
    const dtos = (body as SendNotificationDto[]) ?? [];
    const result = await this.service.createBatch(dtos);
    return { success: true, data: result };
  }

  @Get("user/:userId")
  async listByUser(
    @Param("userId") userId: string,
    @Query("unread") unread: string,
  ): Promise<{ success: true; data: unknown }> {
    const result = await this.service.listByUser(userId, unread === "true");
    return { success: true, data: result };
  }

  @Get("user/:userId/page")
  async listByUserPaginated(
    @Param("userId") userId: string,
    @Query("page") page: string,
    @Query("pageSize") pageSize: string,
  ): Promise<{ success: true; data: unknown }> {
    const pageNum = Number(page) > 0 ? Number(page) : 1;
    const pageSizeNum = Number(pageSize) > 0 ? Number(pageSize) : 20;
    const result = await this.service.listByUserWithPagination(
      userId,
      pageNum,
      pageSizeNum,
    );
    return { success: true, data: result };
  }

  @Put(":id/read")
  async markAsRead(@Param("id") id: string): Promise<{ success: true }> {
    await this.service.markAsRead(id);
    return { success: true };
  }

  @Get("search")
  async search(
    @Req() req: AuthedRequest,
    @Query("q") q: string,
    @Query("userId") userIdParam: string,
  ): Promise<{ success: true; data: unknown }> {
    const userId = getUserIdFromRequest(req) ?? userIdParam;
    if (!userId) {
      throw new HttpException(
        {
          success: false,
          error: {
            code: "MSG_PERMISSION_DENIED",
            message: "Missing user identity",
          },
        },
        HttpStatus.FORBIDDEN,
      );
    }
    const result = await this.service.search(userId, q);
    return { success: true, data: result };
  }
}