package lambda;

import java.util.Map.Entry;

import com.amazonaws.regions.Region;

import com.amazonaws.regions.Regions;

import com.amazonaws.services.dynamodbv2.model.AttributeValue;

import com.amazonaws.services.dynamodbv2.model.StreamRecord;

import com.amazonaws.services.lambda.runtime.Context;

import com.amazonaws.services.lambda.runtime.RequestHandler;

import com.amazonaws.services.lambda.runtime.events.DynamodbEvent;

import com.amazonaws.services.lambda.runtime.events.DynamodbEvent.DynamodbStreamRecord;

import com.amazonaws.services.simpleemail.AmazonSimpleEmailServiceClient;

import com.amazonaws.services.simpleemail.model.Body;

import com.amazonaws.services.simpleemail.model.Content;

import com.amazonaws.services.simpleemail.model.Destination;

import com.amazonaws.services.simpleemail.model.Message;

import com.amazonaws.services.simpleemail.model.SendEmailRequest;

public class LambdaSendMailFunctionHandler implements

RequestHandler<DynamodbEvent, Object> {

@Override

public Object handleRequest(DynamodbEvent input, Context context) {

String employeeId = "";

String employeeName = "";

String expenseType = "";

Double amount = 0.0;

for (DynamodbStreamRecord r : input.getRecords()) {

// context.getLogger().log("Event id: "+r.getEventID());

// context.getLogger().log("Event name: "+r.getEventName());

// context.getLogger().log("Event source: "+r.getEventSource());

StreamRecord sr = r.getDynamodb();

for (Entry<String, AttributeValue> entry : sr.getNewImage()

.entrySet()) {

String k = entry.getKey();

AttributeValue v = entry.getValue();

switch (k) {

case "employee_id":

employeeId = v.getS();

break;

case "employee_name":

employeeName = v.getS();

break;

case "expense_type":

expenseType = v.getS();

break;

case "amount":

amount = Double.valueOf(entry.getValue().getN());

break;

default:

context.getLogger().log("Key " + k + " is unknown.");

}

}

}

context.getLogger().log(

"ENTRY: " + employeeId + " | " + employeeName + " | "

+ expenseType + " | " + amount);

String from = "klems@tu-berlin.de"; // TODO Replace with your "From" address.

// This address must be verified.

String to = "klems@tu-berlin.de"; // TODO Replace with a "To" address. If you

// have not yet requested production

// access, this address must be

// verified.

String subject = String.format("Expense reimbursment request by %s",

employeeName);

// TODO Replace with your own approval URL

String approvalUrl = String

.format("https://.......execute-api.eu-west-1.amazonaws.com/test/reimbursment?id=%s",

employeeId);

String body = String

.format("Hello boss,\n\nplease approve my expense reimbursment:\n%s\n\nExpense type: %s\nAmount: %s EUR\n\nThanks!\n%s\nEmployee ID: %s ",

approvalUrl, expenseType, amount, employeeName,

employeeId);

sendMail(from, to, subject, body);

context.getLogger().log("Email sent from " + from + " to " + to);

return null;

}

private void sendMail(final String from, final String to,

final String subjectStr, final String bodyStr) {

// Construct an object to contain the recipient address.

Destination destination = new Destination()

.withToAddresses(new String[] { to });

// Create the subject and body of the message.

Content subject = new Content().withData(subjectStr);

Content textBody = new Content().withData(bodyStr);

Body body = new Body().withText(textBody);

// Create a message with the specified subject and body.

Message message = new Message().withSubject(subject).withBody(body);

// TODO Assemble the email.

// TODO Send the email.

}

}