import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import { inject, Injectable } from '@angular/core';
import { firstValueFrom } from 'rxjs';
import { CLOUD_FUNCTION_BASE_URL } from './admin.constants';
import { AdminSessionService } from './admin-session.service';
import { CloudEnvelope, LegacyCloudEnvelope } from './admin.models';

export class CloudFunctionError extends Error {
  constructor(message: string, readonly status = 0, readonly payload?: unknown) {
    super(message);
  }
}

@Injectable({ providedIn: 'root' })
export class CloudFunctionsService {
  private readonly http = inject(HttpClient);
  private readonly sessions = inject(AdminSessionService);

  async admin<T>(operation: string, params: Record<string, unknown> = {}): Promise<T> {
    const token = this.sessions.session()?.sessionToken;
    if (!token) throw new CloudFunctionError('管理员会话已失效', 401);
    try {
      const envelope = await firstValueFrom(this.http.post<CloudEnvelope<T>>(
        `${CLOUD_FUNCTION_BASE_URL}/xiaoshu/admin/gateway`,
        { token, params: { operation, ...params } },
      ));
      if (!envelope.success) throw new CloudFunctionError(envelope.message || envelope.error || '云函数执行失败');
      return envelope.data;
    } catch (error) {
      if (error instanceof CloudFunctionError) throw error;
      if (error instanceof HttpErrorResponse) {
        const payload = error.error as { error?: string; message?: string } | null;
        if (error.status === 401 || error.status === 403) this.sessions.logout();
        throw new CloudFunctionError(payload?.message || payload?.error || error.message, error.status, payload);
      }
      throw new CloudFunctionError(error instanceof Error ? error.message : '未知云函数错误');
    }
  }

  async app<T>(action: string, params: Record<string, unknown> = {}): Promise<T> {
    const token = this.sessions.session()?.sessionToken;
    if (!token) throw new CloudFunctionError('管理员会话已失效', 401);
    try {
      const envelope = await firstValueFrom(this.http.post<LegacyCloudEnvelope<T>>(
        `${CLOUD_FUNCTION_BASE_URL}/xiaoshu/app/gateway`,
        { token, params: { action, ...params } },
      ));
      if (envelope.retcode === -1) throw new CloudFunctionError(envelope.retmsg || '云函数执行失败');
      return envelope.result;
    } catch (error) {
      if (error instanceof CloudFunctionError) throw error;
      if (error instanceof HttpErrorResponse) {
        const payload = error.error as { error?: string; message?: string; retmsg?: string } | null;
        if (error.status === 401 || error.status === 403) this.sessions.logout();
        throw new CloudFunctionError(payload?.retmsg || payload?.message || payload?.error || error.message, error.status, payload);
      }
      throw new CloudFunctionError(error instanceof Error ? error.message : '未知云函数错误');
    }
  }
}