import { HttpException, HttpStatus, Inject, Injectable, Res, UploadedFile } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { InjectRepository } from '@nestjs/typeorm';
import * as nodemailer from 'nodemailer';
import { EventosService } from 'src/eventos/eventos.service';
import { Participante } from 'src/participante/participante.entity';
import { Repository } from 'typeorm';
import { EmailDto } from './dto/emailDto.dto';
import * as xlsx from 'xlsx';
import * as pdfMake from 'pdfmake/build/pdfmake';
import * as pdfFonts from 'pdfmake/build/vfs_fonts';
/* import * as PDFDocument from 'pdfkit'; */
import * as fs from 'fs';
import * as path from 'path';
import { PDFDocument, StandardFonts, rgb } from 'pdf-lib';

@Injectable()
export class EmailService {
  private transporter;

  constructor(
    @InjectRepository(Participante)
    private participanteRepository: Repository<Participante>,
    private configService: ConfigService,
  ) {
    this.transporter = nodemailer.createTransport({
      service: this.configService.get('NODEMAILER_SERVICE'),
      auth: {
        user: this.configService.get<string>('NODEMAILER_USER'),
        pass: this.configService.get<string>('NODEMAILER_PASWORD'),
      },
    });
  }

  async sendEmail(id: number, message: EmailDto) {
    const participantes = await this.getEmailDeParticipantes(id);
    participantes.map((res) => {
      const emailDestinatario = res.email;
      this.transporter.sendMail({
        to: emailDestinatario,
        subject: message.subject,
        text: message.text,
      });
      /*console.log("Email enviado a: ", res)*/
    });
  }

  async getEmailDeParticipantes(idEvento: number) {
    const participantes = await this.participanteRepository
      .createQueryBuilder('participante')
      .innerJoin('participante.eventosParticipante', 'eventoParticipante')
      .innerJoin('eventoParticipante.evento', 'evento')
      .where('evento.id_evento = :idEvento', { idEvento })
      .select(['participante.email'])
      .getMany();

    return participantes;
  }

  async sendConstancias(file, nombreEvento) {
    /* console.log(file) */
    const workbook = xlsx.read(file.buffer);
    const worksheet = workbook.Sheets[workbook.SheetNames[0]];
    const data = xlsx.utils.sheet_to_json(worksheet);

    for (const row of data as Row[]) {
      const pdfDoc = await PDFDocument.create();
      const page = pdfDoc.addPage();
      page.setSize(792, 612);

      const font = await pdfDoc.embedFont(StandardFonts.HelveticaBold);
      const fontSize = 30;
      const text = 'Constancia de asistencia';
      const textWidth = font.widthOfTextAtSize(text, fontSize);
      const textHeight = font.heightAtSize(fontSize);

      page.drawText(text, {
        x: (page.getWidth() - textWidth) / 2,
        y: (page.getHeight() - textHeight) / 2,
        size: fontSize,
        font: font,
        color: rgb(0/255, 0/255, 0/255),
      });

      const { width, height } = page.getSize();
      page.drawText(
        `Se le otorga la constancia por su asistencia al evento: ${nombreEvento}`,
        {
          x: 50,
          y: height - 50,
          size: 12,
          font: await pdfDoc.embedFont('Helvetica'),
        },
      );
      page.drawText(
        `A ${row['Apellido Paterno']} ${row['Apellido Materno']} ${row.Nombre}`,
        {
          x: 50,
          y: height - 80,
          size: 12,
          font: await pdfDoc.embedFont('Helvetica'),
        },
      );
      const pdfBytes = await pdfDoc.save();
      const attachment = {
        filename: `Constancia ${nombreEvento} - ${row.Nombre}_${row['Apellido Paterno']}.pdf`,
        content: pdfBytes,
      };
      /*       const blob = new Blob([pdfBytes], { type: 'application/pdf' });
      const url = URL.createObjectURL(blob); */
      this.transporter.sendMail({
        to: row.Email,
        subject: `Constancia de asistencia a "${nombreEvento}"`,
        text: `¡Un saludo ${row.Nombre}! Aquí está tu constancia de asistencia por el evento "${nombreEvento}". Agradecemos tu asistencia y constancia, esperamos seguir viéndote en eventos futuros.`,
        attachments: [attachment],
      });
    }
  }
}