var AWS = require('aws-sdk');

exports.sendSMS = (to_number, message, callback) => {

    AWS.config.update({
        accessKeyId: 'YOUR_KEY',
        secretAccessKey: 'YOUR_SECRET',
        // Select a location that has SMS support
        region: 'us-east-1'
    });

    var sns = new AWS.SNS();
    var sns_topic_arn = 'arn:aws:sns:us-east-1:ACCOUNT_ID:TOPIC_HERE';

    sns.subscribe({
        Protocol: 'sms',
        TopicArn: sns_topic_arn,
        Endpoint: to_number
    }, function(error, data) {
        if (error) {
            console.log("Error When Subscribed", error);
            return callback(false);
        }

        console.log("subscribe data", data);
        var SubscriptionArn = data.SubscriptionArn;

        var params = {
            attributes: {
                'DefaultSMSType': 'Transactional',
            }
        };
        sns.setSMSAttributes(params, function(err, data) {
            if (err) console.log(err, err.stack);
            else console.log(data);
        });

        var params = {
            TargetArn: sns_topic_arn,
            Message: message,
            Subject: 'Subject Goes Here'
        };
        sns.publish(params, function(err_publish, data) {
            if (err_publish) console.log('Error Sending Message', err_publish);
            else console.log('Sent Message:', data.MessageId);

            var params = {
                SubscriptionArn: SubscriptionArn
            };

            sns.unsubscribe(params, function(err, data) {
                if (err) {
                    console.log("err when unsubscribe", err);
                }
                return callback(err_publish != null);
            });
        });

    });
}