---
AWSTemplateFormatVersion: "2010-09-09"
Description: >
  Basic Template
Parameters:
  ApplicationName:
    Type: String
    Description: Application Name
  Environment:
    Type: String
    Default: Test
    Description: Environment
    AllowedValues:
      - Dev
      - Test
  TestEnvironment:
    Type: String
    Default: Test
    Description: Another Environment
    AllowedValues:
      - Dev
      - Test
      - Prod
  BillingContact:
    Type: String
    Default: billing@example.com
    AllowedPattern: '^[A-Za-z0-9._%+-]+@example.com$'
  OperationsContact:
    Type: String
    Default: operations@example.com
    AllowedPattern: '^[A-Za-z0-9._%+-]+@example.com$'
Conditions:
  isProd:
    Fn::Equals: [!Ref Environment, 'Prod']
Resources:
  untaggedInstance:
    Type: AWS::EC2::Instance
    Properties:
      ImageId: ami-123456
  myInstance:
    Type: AWS::EC2::Instance
    Properties:
      ImageId: ami-123456
      Tags:
      -
        Key: application
        Value: !Ref ApplicationName
      -
        Key: environment
        Value: !Ref Environment
      -
        Key: environment
        Value: !If [isProd, 'Yes', !Ref Environment]
      -
        Key: environment
        Value: !Ref TestEnvironment
      -
        Key: billing_contact
        Value: !Ref BillingContact
      -
        Key: operations_contact
        Value: !Ref OperationsContact
      -
        Key: security_contact
        Value: security@example.c