const AWS = require("aws-sdk");
const crypto = require("crypto");

const Cognito = new AWS.CognitoIdentityServiceProvider();

exports.handler = async (event) => {
  const clientId = process.env.COGNITO_CLIENT_ID;
  const clientSecret = process.env.COGNITO_CLIENT_SECRET;
  const {username, password, email} = event;

  const secretHash = crypto.createHmac("SHA256", clientSecret).update(email + clientId).digest("base64");

  const params = {
    ClientId: clientId,
    SecretHash: secretHash,
    Password: password,
    Username: username,
    UserAttributes: [
        {
            Name: "email",
            Value: email
        }
    ]
  };

  try {
      const authRes = await Cognito.signUp(params).promise();
      return {
          data: authRes
      }
  } catch(err) {
      console.log("Error: ", err);
      return {
          err
      }
  }
};

{
  "Version": "2012-10-17",
  "Statement": [
      {
        "Effect": "Allow",
        "Action": "logs:CreateLogGroup",
        "Resource": "arn:aws:logs:us-east-1:<account_id>:*"
      },
      {
        "Effect": "Allow",
        "Action": [
            "logs:CreateLogStream",
            "logs:PutLogEvents"
        ],
        "Resource": [
            "arn:aws:logs:us-east-1:<account_id>:log-group:/aws/lambda/create_user:*"
        ]
      }
  ]
}