AWSTemplateFormatVersion: 2010-09-09
Parameters:
    cidrBlock :
        Type: String
        AllowedPattern: ^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])(\/([0-9]|[1-2][0-9]|3[0-2]))$
    count:
        Type: Number
        MinValue: 1
        MaxValue: 256
    maskSizeForIPv4:
        Type: Number
        MinValue: 1
        MaxValue: 32
    maskSizeForIPv6:
        Type: Number
        MinValue: 1
        MaxValue: 128
    vpcSubnetPrefix:
        Type: String
        Default: '10.0'
        AllowedPattern: ^(?:[0-9]{1,3}\\.){1}[0-9]{1,3}$
Resources:
    Subnet1:
        Type: AWS::EC2::Subnet
        Properties:
            AssignIpv6AddressOnCreation: true
            VpcId: !Ref VPC
            #Test Ipv4 CidrBlock
            CidrBlock: !Select [0, !Cidr [!Ref cidrBlock, !Ref count, !Ref maskSizeForIPv4]]
            #Test Ipv6 CidrBlock
            Ipv6CidrBlock: !Select [0, !Cidr [!Select [0, !GetAtt VPC.Ipv6CidrBlocks], !Ref count, !Ref maskSizeForIPv6]]
        DependsOn: Ipv6VPCCidrBlock
    Subnet2:
        Type: AWS::EC2::Subnet
        Properties:
            AssignIpv6AddressOnCreation: true
            VpcId: !Ref VPC
            #Test Ipv4 CidrBlock
            CidrBlock: !Select [1, !Cidr [!Ref cidrBlock, !Ref count, !Ref maskSizeForIPv4]]
            #Test Ipv6 CidrBlock
            Ipv6CidrBlock: !Select [1, !Cidr [!Select [0, !GetAtt VPC.Ipv6CidrBlocks], !Ref count, !Ref maskSizeForIPv6]]
        DependsOn: Ipv6VPCCidrBlock
    Subnet3:
        Type: AWS::EC2::Subnet
        Properties:
            AssignIpv6AddressOnCreation: true
            VpcId: !Ref VPC
            CidrBlock: !Select [1, !Cidr [!Sub "${VPCSubnetPrefix}.48.0/23", !Ref count, !Ref maskSizeForIPv4]]
        DependsOn: Ipv6VPCCidrBlock
    VPC:
        Type: AWS::EC2::VPC
        Properties:
          CidrBlock: !Ref cidrBlock
    Ipv6VPCCidrBlock:
        Type: AWS::EC2::VPCCidrBlock
        Properties:
            AmazonProvidedIpv6CidrBlock: true
            VpcId: !Ref VPC