import { Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { buildIntegrations, type Integration } from './integrations';

@Injectable()
export class IntegrationsService {
  constructor(private readonly config: ConfigService) {}

  async list(): Promise<{ items: Integration[] }> {
    const [viaCep, nominatim, firebase] = await Promise.all([
      this.probeViaCep(),
      this.probeNominatim(),
      this.probeFirebase(),
    ]);
    return {
      items: buildIntegrations({
        viaCep,
        nominatim,
        google: this.googleConfigured(),
        firebase,
      }),
    };
  }

  private googleConfigured() {
    return Boolean(this.config.get<string>('GOOGLE_CLIENT_ID') && this.config.get<string>('GOOGLE_CLIENT_SECRET'));
  }

  private async probeViaCep() {
    return this.ok(async () => {
      const response = await fetch('https://viacep.com.br/ws/01001000/json/', {
        signal: AbortSignal.timeout(4000),
      });
      if (!response.ok) {
        return false;
      }
      const data = (await response.json()) as { erro?: boolean; localidade?: string };
      return !data.erro && Boolean(data.localidade);
    });
  }

  private async probeNominatim() {
    return this.ok(async () => {
      const query = new URLSearchParams({
        format: 'json',
        limit: '1',
        countrycodes: 'br',
        q: 'Sao Paulo, SP, Brasil',
      });
      const response = await fetch(`https://nominatim.openstreetmap.org/search?${query.toString()}`, {
        headers: { 'User-Agent': 'SinkaLogistica/1.0 (desafio; tina.r@example.net)' },
        signal: AbortSignal.timeout(4000),
      });
      if (!response.ok) {
        return false;
      }
      const rows = (await response.json()) as unknown[];
      return rows.length > 0;
    });
  }

  private async probeFirebase() {
    const url = (this.config.get<string>('FIREBASE_DATABASE_URL')?.replace(/\/$/, '') ||
      'https://sinka-8ec10-default-rtdb.firebaseio.com');
    return this.ok(async () => {
      const response = await fetch(`${url}/.json?shallow=true`, {
        signal: AbortSignal.timeout(4000),
      });
      return response.ok;
    });
  }

  private async ok(probe: () => Promise<boolean>) {
    try {
      return await probe();
    } catch {
      return false;
    }
  }
}