ocr tesseract

images.service.ts

import { HttpStatus, Injectable } from '@nestjs/common';
import { StatusMessage } from 'src/filters/message.constant';
import { Response } from 'src/models/response.model';
import { createWorker } from 'tesseract.js';
import { ResultFindTotalPrice } from './images';
import * as fs from 'fs';

require('dotenv').config();

@Injectable()
export class ImagesService {
  async upload(files: Array<Express.Multer.File>) {
    const { URL } = process.env;

    const worker = createWorker({});

    await worker.load();
    await worker.loadLanguage('ind');
    await worker.initialize('ind');
    const {
      data: { text },
    } = await worker.recognize(`${URL}${files[0]?.filename}`);
    await worker.terminate();

    const findTotalPrice = (text: string): ResultFindTotalPrice => {
      const result: ResultFindTotalPrice = {
        isFoundTotalPrice: false,
        totalPrice: 0,
      };
      const tempArray = text.split('\n');
      let matchPrice = '';

      tempArray.map((res) => {
        if (res.toLowerCase().includes('total' || 'total harga')) {
          matchPrice = res;
        }
      });

      if (matchPrice) {
        const totalValue = matchPrice
          .toLowerCase()
          .replace(/([,.])\s/g, '')
          .split('total')[1];

        result.isFoundTotalPrice = true;
        result.totalPrice = Number(totalValue);
      } else {
        result.isFoundTotalPrice = false;
        result.totalPrice = 0;
      }

      return result;
    };

    if (findTotalPrice(text).isFoundTotalPrice) {
      return new Response(
        StatusMessage.SUCCESS_FIND_TOTAL_PRICE,
        HttpStatus.OK,
        findTotalPrice(text),
      );
    } else {
      const path = `./public/img/${files[0]?.filename}`;
      fs.unlink(path, (err) => {
        console.log(err);
      });
      return new Response(
        StatusMessage.NO_DATA_TOTAL_PRICE,
        HttpStatus.NO_CONTENT,
        {},
      );
    }
  }
}