// src/drive/drive.service.ts
import {
  BadRequestException,
  Injectable,
  InternalServerErrorException,
} from '@nestjs/common';
import { google } from 'googleapis';
import * as fs from 'fs';

@Injectable()
export class DriveService {
  private SCOPES = ['https://www.googleapis.com/auth/drive'];

  private loadCredentials() {
    try {
      const oAuth2Client = new google.auth.OAuth2(
        process.env.CLIENT_ID,
        process.env.CLIENT_SECRET,
      );

      oAuth2Client.setCredentials({
        refresh_token: process.env.REFRESH_TOKEN,
      });

      return oAuth2Client;
    } catch (err) {
      throw new InternalServerErrorException(
        'Error al cargar credenciales de Google Drive',
      );
    }
  }

  async list(pageToken = '') {
    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    try {
      const res = await drive.files.list({
        corpora: 'user',
        supportsAllDrives: true,
        includeItemsFromAllDrives: true,
        spaces: 'drive',
        pageSize: 1000,
        pageToken,
        orderBy: 'name',
      });
      return res.data;
    } catch (err) {
      throw new InternalServerErrorException(
        'Error al listar archivos: ' + err.message,
      );
    }
  }

  async deleteFile(fileId: string) {
    if (fileId === process.env.CARPETA) {
      throw new BadRequestException(
        'No se puede eliminar este archivo/carpeta.',
      );
    }
    console.log('Eliminando archivo de Drive, ID:', fileId);
    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    try {
      return await drive.files.delete({ fileId });
    } catch (err) {
      console.error('Error al eliminar archivo de Drive:', err.message);
      return 0;
    }
  }

  async uploadFile(
    filePath: string,
    name: string,
    mimeType: string,
    parent: string,
  ) {
    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    const requestBody = {
      name,
      parents: [parent],
    };

    const media = {
      mimeType,
      body: fs.createReadStream(filePath),
    };

    try {
      const res = await drive.files.create({
        requestBody,
        media,
        fields: 'id',
        supportsAllDrives: true,
      });

      fs.unlinkSync(filePath);
      console.log('Archivo subido a Drive, ID:', res.data.id);
      return res.data.id!;
    } catch (err) {
      throw new InternalServerErrorException(
        'Error al subir archivo: ' + err.message,
      );
    }
  }

  async mkDir(name: string): Promise<string> {
    if (!name) {
      throw new BadRequestException('Nombre de carpeta inválido');
    }

    if (!process.env.CARPETA) {
      throw new InternalServerErrorException('CARPETA no configurada');
    }

    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    const requestBody = {
      name,
      mimeType: 'application/vnd.google-apps.folder',
      parents: [process.env.CARPETA],
    };

    try {
      const res = await drive.files.create({
        requestBody,
        fields: 'id',
        supportsAllDrives: true,
      });

      if (!res.data.id) {
        throw new BadRequestException('No se pudo crear la carpeta');
      }

      return res.data.id;
    } catch (err) {
      throw new InternalServerErrorException(
        'Error al crear carpeta: ' + err.message,
      );
    }
  }

  async update(fileId: string, addParents: string, removeParents: string) {
    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    try {
      const res = await drive.files.update({
        fileId,
        addParents,
        removeParents,
        supportsAllDrives: true,
      });
      return res.data;
    } catch (err) {
      throw new InternalServerErrorException(
        'Error al actualizar archivo: ' + err.message,
      );
    }
  }

  async folder(numeroCuenta: string): Promise<string> {
    if (!process.env.CARPETA) {
      throw new InternalServerErrorException('CARPETA no configurada');
    }

    const authClient = this.loadCredentials();
    const drive = google.drive({ version: 'v3', auth: authClient });

    const res = await drive.files.list({
      q: `
        mimeType='application/vnd.google-apps.folder'
        and name='${numeroCuenta}'
        and '${process.env.CARPETA}' in parents
        and trashed=false
      `,
      fields: 'files(id, name)',
      supportsAllDrives: true,
      includeItemsFromAllDrives: true,
    });

    if (res.data.files?.length) {
      return res.data.files[0].id!;
    }

    return this.mkDir(numeroCuenta);
  }
}