data "aws_vpc" "this" {
  id = var.existing_vpc_id
}

data "aws_subnet" "public" {
  for_each = toset(var.existing_public_subnet_ids)
  id       = each.value
}

data "aws_subnet" "instance" {
  id = local.instance_subnet_id
}

check "vpc_cidr" {
  assert {
    condition     = data.aws_vpc.this.cidr_block == local.vpc_cidr
    error_message = "existing_vpc_id must be the After Hours VPC ${local.vpc_cidr}."
  }
}

check "public_subnets_in_vpc" {
  assert {
    condition     = alltrue([for subnet in data.aws_subnet.public : subnet.vpc_id == var.existing_vpc_id])
    error_message = "existing_public_subnet_ids must all belong to existing_vpc_id."
  }
}

check "alb_subnet_azs" {
  assert {
    condition     = length(distinct([for subnet in data.aws_subnet.public : subnet.availability_zone])) >= 2
    error_message = "ALB subnets must cover at least two availability zones."
  }
}