'use strict';
const assert = require('assert');
const path = require('path');
const {BigQuery} = require('@google-cloud/bigquery');
const {Storage} = require('@google-cloud/storage');
const bigquery = new BigQuery();
const storage = new Storage({
    projectId: 'jsonsuploading',
  });
const tableschema = [
  {
      "name": "date",
      "type": "DATE",
      "mode": "NULLABLE"
  },
  {
      "name": "location",
      "type": "STRING",
      "mode": "NULLABLE"
  },
  {
      "name": "purchasedItems",
      "type": "RECORD",
      "mode": "REPEATED",
      "fields": [
          {
              "name": "price",
              "type": "INTEGER",
              "mode": "NULLABLE"
          },
          {
              "name": "quantity",
              "type": "INTEGER",
              "mode": "NULLABLE"
          },
          {
              "name": "description",
              "type": "STRING",
              "mode": "NULLABLE"
          },
          {
              "name": "sku",
              "type": "STRING",
              "mode": "NULLABLE"
          }
      ]
  },
  {
      "name": "custType",
      "type": "STRING",
      "mode": "NULLABLE"
  },
  {
      "name": "custID",
      "type": "STRING",
      "mode": "NULLABLE"
  },
  {
      "name": "orderID",
      "type": "STRING",
      "mode": "NULLABLE"
  }
];


exports.bqload = (event) => {
  const file = event;
  console.log(`File ${file.name} start procesing.`);
  const datasetId = 'uploading';
  const tableId = path.parse(file.name).name;
  const ext = path.parse(file.name).ext
  const jobMetadata = {
    schema: {
      fields: tableschema
    },
    sourceFormat : 'NEWLINE_DELIMITED_JSON',
    createDisposition : 'CREATE_IF_NEEDED',
    writeDisposition: 'WRITE_TRUNCATE'
  };

  if (ext == '.json') {
    return bigquery
        .dataset(datasetId)
        .table(tableId)
        .load(storage.bucket(file.bucket).file(file.name), jobMetadata)
        .then(results => {
            const job = results[0];
            assert.equal(job.status.state, 'DONE');
            console.log(`File ${file.name} processed. Job ${job.id} completed.`);
            const errors = job.status.errors;
            if (errors && errors.length > 0) {
            throw errors;
            }
        })
        .catch(err => {
            console.error('ERROR:', err);
        });
    } else {
        return console.error(`File ${file.name} uploaded has ${ext} extension`);
    }

};