Bsbsn

'use strict';

/**

* @author - jedwards

* @date - September 2017

*/

// Constants required for analyzing the drivers license

const IDENTITY_DOCUMENT_LABEL = 'identity document';

// Super basic/specific text matching patterns (start, offset, stop/length) to fill in the CA Driver's License metadata fields

const driversLicenseFields = {

	'idNumber' : {

		'start': 'LICENSE',

		'offset': 11,

		'numChars': 8

	},

	'firstName': {

		'start': 'FN',

		'offset': 3,

		'stop': '\n'

	},

	'lastName': {

		'start': 'LN',

		'offset': 3,

		'stop': 'FN'

	},

	'address': {

		'start': 'FN',

		'offset': 3,

		'stop': 'DOB'

	},

	'gender': {

		'start': 'SEX',

		'offset': 4,

		'numChars': 1

	},

	'dateOfBirth': {

		'start': 'DOB',

		'offset': 4,

		'numChars': 10

	},

	'issuingDate': {

		'start': 'ISSEE\nDD',

		'offset': 31,

		'numChars': 10

	},

	'expirationDate': {

		'start': 'EXP',

		'offset': 4,

		'numChars': 10

	}

}

/**

* exports.getMetadataValueForDriversLicense()

*

* Helper function to extract the text found by the Google Cloud Vision API to the corresponding CA Driver's License field.

*

* Input:

* (JSON) annotationImageResponse - the classifications found by the Cloud Vision API in JSON format

*

* Output:

* (JSON) - the formatted metadata for the CA Driver's License

*/

exports.getMetadataValueForDriversLicense = (annotationImageResponse) => {

	console.log(annotationImageResponse);

	var driversLicenseMetadata = {};

	// If this is not an identity document, the "identity document" label will not be returned as part of the

	// labelAnnotations response

	var isIdentityDocument = false;

	if (annotationImageResponse.hasOwnProperty('labelAnnotations')) {

		annotation = annotationImageResponse['labelAnnotations'];

		if (annotation.length > 0) {

			for (var i = 0; i < annotation.length - 1; i++) {

				if (annotation[i].description == IDENTITY_DOCUMENT_LABEL) {

					isIdentityDocument = true;

					break;

				}

			}

		}

	}

	if (!isIdentityDocument) {

		return driversLicenseMetadata;

	}

	// This is an identity document, so parse the text that Google Cloud Vision found

	if (annotationImageResponse.hasOwnProperty('fullTextAnnotation')) {

		var annotation = annotationImageResponse['fullTextAnnotation'];

		if (annotation && annotation.hasOwnProperty('text')) {

			var text = annotation.text;

			var info = '';

			for (var key in driversLicenseFields) {

				var field = driversLicenseFields[key];

				var start = text.indexOf(field['start']) + field['offset'];

				// For the address, there's no good text to signal the beginning

				// of the field. Instead we can add the length of the first name

				// as an additional offset (since they are side-by-side)

				if (key === 'address') {

					start += driversLicenseMetadata['firstName'].length

				}

				var end = -1;

				if (start > -1) {

					if (field['stop']) {

						// Stop at the occurrence of the "stop" string that first appears

						// after the "start" string

						end = text.indexOf(field['stop'], start);

					} else {

						// This field has a fixed number of characters

						end = start + field['numChars'];

					}

					info = text.substring(start, end);

					info = info.replace(new RegExp('/', 'g'), '-');

				}

				driversLicenseMetadata[key] = info;

				info = '';

			}

		}

	}

	return driversLicenseMetadata;

}