resource "random_pet" "prefix" {
  prefix = var.prefix
  length = 1
}
resource "azurerm_resource_group" "rg" {
  name     = "${random_pet.prefix.id}-rg"
  location = var.resource_group_location
}

resource "azurerm_virtual_network" "vnet" {
  name                = "${random_pet.prefix.id}-vnet"
  address_space       = ["10.0.0.0/16"]
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
}

resource "azurerm_subnet" "subnet" {
  name                 = "AzureFirewallSubnet"
  resource_group_name  = azurerm_resource_group.rg.name
  virtual_network_name = azurerm_virtual_network.vnet.name
  address_prefixes     = ["10.0.1.0/24"]
}

resource "azurerm_public_ip" "pip" {
  name                = "${random_pet.prefix.id}-pip"
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
  allocation_method   = "Static"
  sku                 = "Standard"
}

resource "azurerm_firewall" "main" {
  name                = "${random_pet.prefix.id}-fw"
  location            = azurerm_resource_group.rg.location
  resource_group_name = azurerm_resource_group.rg.name
  sku_name            = "AZFW_VNet"
  sku_tier            = "Standard"

  ip_configuration {
    name                 = "configuration"
    subnet_id            = azurerm_subnet.subnet.id
    public_ip_address_id = azurerm_public_ip.pip.id
  }
}

resource "azurerm_firewall_application_rule_collection" "app-rc" {
  name                = "${random_pet.prefix.id}-app-rc"
  azure_firewall_name = azurerm_firewall.main.name
  resource_group_name = azurerm_resource_group.rg.name
  priority            = 100
  action              = "Allow"

  rule {
    name = "testrule"

    source_addresses = [
      "10.0.0.0/16",
    ]

    target_fqdns = [
      "*.google.com",
    ]

    protocol {
      port = "443"
      type = "Https"
    }
  }
}

resource "azurerm_firewall_network_rule_collection" "net-rc" {
  name                = "${random_pet.prefix.id}-net-rc"
  azure_firewall_name = azurerm_firewall.main.name
  resource_group_name = azurerm_resource_group.rg.name
  priority            = 100
  action              = "Allow"

  rule {
    name = "dnsrule"

    source_addresses = [
      "10.0.0.0/16",
    ]

    destination_ports = [
      "53",
    ]

    destination_addresses = [
      "8.8.8.8",
      "8.8.4.4",
    ]

    protocols = [
      "TCP",
      "UDP",
    ]
  }
}