nat-gw.tf

locals {
  nat_gateway_count     = var.single_nat_gateway && var.enable_nat_gateway && local.enabled ? 1 : var.nat_gateway_per_az && var.enable_nat_gateway && local.enabled ? length(data.aws_availability_zones.azs.names) : var.enable_nat_gateway && local.enabled ? 1 : 0
  reuse_existing_eips   = length(var.nat_eips_list) > 0
  nat_gateway_eip_count = local.reuse_existing_eips ? 0 : local.nat_gateway_count
  eip_allocation_ids    = local.reuse_existing_eips ? data.aws_eip._.*.id : aws_eip._.*.id
}


resource "aws_eip" "_" {
  count = local.enabled ? local.nat_gateway_eip_count : 0
  vpc   = true
  tags  = merge(var.additional_tags, tomap({ "Name" = join(local.delimiter, [local.name, count.index]) }))
}

resource "aws_nat_gateway" "_" {
  count         = local.enabled && var.enable_nat_gateway ? local.nat_gateway_count : 0
  allocation_id = element(local.eip_allocation_ids, count.index)
  subnet_id     = element(aws_subnet.public.*.id, count.index)
  tags          = merge(var.additional_tags, tomap({ "Name" = join(local.delimiter, [local.name, count.index]) }))

  lifecycle {
    create_before_destroy = true
  }
}