const error = require('../error');
const path = require('path');
const parser = require('@apidevtools/json-schema-ref-parser');

const Ajv = require('ajv');
const addFormats = require('ajv-formats');
const ajv = new Ajv({
	verbose: true,
	validateSchema: true,
	allErrors: false,
	coerceTypes: true,
	strict: false,
});
addFormats(ajv);

/**
 * @param {Object} schema
 * @param {Object} payload
 * @returns {Promise}
 */
function apiValidator(schema, payload /*, description */) {
	return new Promise(function Promise_apiValidator(resolve, reject) {
		if (typeof payload === 'undefined') {
			reject(new error.ValidationError('Payload is undefined'));
		}

		const validate = ajv.compile(schema);
		const valid = validate(payload);

		if (valid && !validate.errors) {
			resolve(payload);
		} else {
			const message = ajv.errorsText(validate.errors);
			const err = new error.ValidationError(message);
			err.debug = [validate.errors, payload];
			reject(err);
		}
	});
}

apiValidator.loadSchemas = parser.dereference(path.resolve('schema/index.json')).then((schema) => {
	ajv.addSchema(schema);
	return schema;
});

module.exports = apiValidator;