Description: Master stack which creates all required nested stacks

Parameters:
  TemplatePath:
    Type: String
    Description: S3Bucket Path where the templates are stored
  VPCID:
    Type: "AWS::EC2::VPC::Id"
    Description: Enter a valid VPC Id
  PrivateSubnet1:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of private subnet in AZ1
  PrivateSubnet2:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of private subnet in AZ2
  PublicSubnet1:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of public subnet in AZ1
  PublicSubnet2:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of public subnet in AZ2
  S3BucketName:
    Type: String
    Description: Name of the S3 bucket to allow access to the Web Server IAM Role.
  KeyPair:
    Type: "AWS::EC2::KeyPair::KeyName"
    Description: Enter a valid KeyPair Name
  AMIId:
    Type: "AWS::EC2::Image::Id"
    Description: Enter a valid AMI ID to launch the instance
  WebInstanceType:
    Type: String
    Description: Enter one of the possible instance type for web server
    AllowedValues:
      - t2.large
      - m4.large
      - m4.xlarge
      - c4.large
  WebMinSize:
    Type: String
    Description: Minimum number of instances in auto scaling group
  WebMaxSize:
    Type: String
    Description: Maximum number of instances in auto scaling group
  DBSubnetGroup:
    Type: String
    Description: Enter a valid DB Subnet Group
  DBUsername:
    Type: String
    Description: Enter a valid Database master username
    MinLength: 1
    MaxLength: 16
    AllowedPattern: "[a-zA-Z][a-zA-Z0-9]*"
  DBPassword:
    Type: String
    Description: Enter a valid Database master password
    NoEcho: true
    MinLength: 1
    MaxLength: 41
    AllowedPattern: "[a-zA-Z0-9]*"
  DBInstanceType:
    Type: String
    Description: Enter one of the possible instance type for database
    AllowedValues:
      - db.t2.micro
      - db.t2.small
      - db.t2.medium
      - db.t2.large
  Environment:
    Type: String
    Description: Select the appropriate environment
    AllowedValues:
      - dev
      - test
      - uat
      - prod

Resources:
  SecurityStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/security-stack.yml"
      Parameters:
        S3BucketName:
          Ref: S3BucketName
        VPCID:
          Ref: VPCID
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value: SecurityStack

  DatabaseStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/database-stack.yml"
      Parameters:
        DBSubnetGroup:
          Ref: DBSubnetGroup
        DBUsername:
          Ref: DBUsername
        DBPassword:
          Ref: DBPassword
        DBServerSecurityGroup:
          Fn::GetAtt: SecurityStack.Outputs.DBServerSG
        DBInstanceType:
          Ref: DBInstanceType
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value:   DatabaseStack

  ServerStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/server-stack.yml"
      Parameters:
        VPCID:
          Ref: VPCID
        PrivateSubnet1:
          Ref: PrivateSubnet1
        PrivateSubnet2:
          Ref: PrivateSubnet2
        PublicSubnet1:
          Ref: PublicSubnet1
        PublicSubnet2:
          Ref: PublicSubnet2
        KeyPair:
          Ref: KeyPair
        AMIId:
          Ref: AMIId
        WebSG:
          Fn::GetAtt: SecurityStack.Outputs.WebSG
        ELBSG:
          Fn::GetAtt: SecurityStack.Outputs.ELBSG
        DBClientSG:
          Fn::GetAtt: SecurityStack.Outputs.DBClientSG
        WebIAMProfile:
          Fn::GetAtt: SecurityStack.Outputs.WebIAMProfile
        WebInstanceType:
          Ref: WebInstanceType
        WebMinSize:
          Ref: WebMinSize
        WebMaxSize:
          Ref: WebMaxSize
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value: ServerStack

Outputs:
  WebELBURL:
    Description: "URL endpoint of web ELB"
    Value:
      Fn::GetAtt: ServerStack.Outputs.WebELBURL