data "aws_route53_zone" "existing" {
  count        = local.has_domain && !var.create_route53_zone ? 1 : 0
  name         = var.domain_name
  private_zone = false
}

resource "aws_route53_zone" "main" {
  count = local.has_domain && var.create_route53_zone ? 1 : 0
  name  = var.domain_name
}

locals {
  zone_id = local.has_domain ? (
    var.create_route53_zone ? aws_route53_zone.main[0].zone_id : data.aws_route53_zone.existing[0].zone_id
  ) : ""

  api_fqdn  = local.has_domain ? "api.${var.domain_name}" : ""
  data_fqdn = local.has_domain ? "data.${var.domain_name}" : ""
}

resource "aws_acm_certificate" "main" {
  count             = local.has_domain ? 1 : 0
  domain_name       = local.api_fqdn
  subject_alternative_names = [local.data_fqdn]
  validation_method = "DNS"

  lifecycle {
    create_before_destroy = true
  }
}

resource "aws_route53_record" "cert_validation" {
  for_each = local.has_domain ? {
    for option in aws_acm_certificate.main[0].domain_validation_options :
    option.domain_name => {
      name   = option.resource_record_name
      record = option.resource_record_value
      type   = option.resource_record_type
    }
  } : {}

  allow_overwrite = true
  name            = each.value.name
  records         = [each.value.record]
  ttl             = 60
  type            = each.value.type
  zone_id         = local.zone_id
}

resource "aws_acm_certificate_validation" "main" {
  count                   = local.has_domain ? 1 : 0
  certificate_arn         = aws_acm_certificate.main[0].arn
  validation_record_fqdns = [for r in aws_route53_record.cert_validation : r.fqdn]
}

resource "aws_route53_record" "api" {
  count   = local.has_domain ? 1 : 0
  zone_id = local.zone_id
  name    = local.api_fqdn
  type    = "A"

  alias {
    name                   = aws_lb.main.dns_name
    zone_id                = aws_lb.main.zone_id
    evaluate_target_health = true
  }
}

resource "aws_route53_record" "data" {
  count   = local.has_domain ? 1 : 0
  zone_id = local.zone_id
  name    = local.data_fqdn
  type    = "A"

  alias {
    name                   = aws_lb.main.dns_name
    zone_id                = aws_lb.main.zone_id
    evaluate_target_health = true
  }
}