import {
  OnModuleInit,
  Inject,
  Injectable,
  HttpException,
  HttpStatus,
  InternalServerErrorException,
} from '@nestjs/common';

import { firstValueFrom, lastValueFrom, ReplaySubject } from 'rxjs';
import { Link } from '@dadosfera/protospack-v2/dist/lib/Duc/interfaces/entities';
import { DucClient } from '../duc/client.config';
import { ClientGrpc } from '@nestjs/microservices';
import { ProtoServices } from '@dadosfera/protospack-v2/dist/lib/Duc';
import { CustomerUpdateRequest } from '@dadosfera/protospack-v2/dist/lib/Duc/interfaces/messages';
import { ThemeProtoService } from '@dadosfera/protospack-v2/dist/lib/Duc/interfaces/write-service';
import { ThemeRequest } from '@dadosfera/protospack-v2/dist/lib/Duc/interfaces/messages';
import { CustomerThemeRequest, CustomerThemeResponse } from './dtos/customers';
import DadosferaLogger from '@dadosfera/dadosfera-logs';
import { resolve } from 'path';
import { Readable } from 'stream';

type Files = {
  logoWhite: Express.Multer.File,
  logoBlack: Express.Multer.File,
}

// This function will accept any string, which may result in a bug.
@Injectable()
export class ThemeService implements OnModuleInit {
  private themeService: ThemeProtoService;
  private logger: DadosferaLogger;

  constructor(
    @Inject(DucClient.name) private readonly grpcClient: ClientGrpc,
    @Inject(DadosferaLogger)
    dadosferaLogger: DadosferaLogger,
  ) {
    this.logger = dadosferaLogger.logger;
  }

  onModuleInit() {
    this.themeService = this.grpcClient.getService<ThemeProtoService>(
      ProtoServices.ThemeProtoService,
    );
  }

  async createThemeByCustomer(id: string, theme: CustomerThemeRequest & Files) {
    if (!id) {
      this.logger.error('Error - saveCustomertheme - not found id:' + id);
      throw new HttpException(null, HttpStatus.BAD_REQUEST);
    }

    const customerThemeRequest$ = new ReplaySubject<ThemeRequest>();

    customerThemeRequest$.next({
      customerId: id,
      displayName: theme.displayName,
      backgroundColor: theme.backgroundColor,
      textColor: theme.textColor,
      isMetadata: true,
      filename: '',
      chunk: Buffer.alloc(0)
    })

    if(theme.logoBlack) {
      await this.sendFile(theme.logoBlack, customerThemeRequest$);
    }

    if(theme.logoWhite) {
      await this.sendFile(theme.logoWhite, customerThemeRequest$);
    }
    customerThemeRequest$.complete();

    const stream = this.themeService.CustomerCreateTheme(customerThemeRequest$);

    return lastValueFrom(stream);
  }

  async getThemeByCustomer(id: string): Promise<CustomerThemeResponse> {
    if (!id) {
      this.logger.error('Error - getCustomerTheme - not found id:' + id);
      throw new HttpException(null, HttpStatus.BAD_REQUEST);
    }

    const { theme } = await firstValueFrom(
      this.themeService.CustomerGetTheme({
        id
      }),
    );

    return {
      theme
    }
  }

   private async sendFile(file: Express.Multer.File, stream$: ReplaySubject<ThemeRequest>) {
    const bufferStream = new Readable({
      highWaterMark: 1024 * 1024, // 1 MB por chunk
      read() {}
    });
    bufferStream.push(file.buffer);
    bufferStream.push(null);

    return new Promise((resolve, reject) => {
      bufferStream.on('data', (chunk) => {
        console.log('enviando chunk', file.fieldname)
        const mimetype = file.mimetype.split('/')[1]; // example image/jpeg
        const filename = file.fieldname.concat(".", mimetype);
        stream$.next({
          customerId: '',
          displayName: '',
          backgroundColor: '',
          textColor: '',
          isMetadata: false,
          filename: filename,
          chunk: chunk
        });
      });

      bufferStream.on('end', () => {
        console.log('terminou de enviar')
        resolve(file.filename)
      });

      bufferStream.on('error', (err) => {
        console.error('Erro no stream:', err);
        reject(err);
      });
    });
  }

}