# AdGuard Home — household DNS with ad blocking, local resolution, DoH via dns.nook.family, and DoT via dot.nook.family:853

resource "kubernetes_namespace" "dns" {
  metadata {
    name = "dns"
    labels = {
      managed-by = "terraform"
      tier       = "infrastructure"
    }
  }
}

resource "kubernetes_persistent_volume_claim" "adguard_config" {
  wait_until_bound = false
  metadata {
    name      = "adguard-config"
    namespace = kubernetes_namespace.dns.metadata[0].name
  }
  spec {
    access_modes = ["ReadWriteOnce"]
    resources {
      requests = {
        storage = "1Gi"
      }
    }
  }
}

resource "kubernetes_persistent_volume_claim" "adguard_data" {
  wait_until_bound = false
  metadata {
    name      = "adguard-data"
    namespace = kubernetes_namespace.dns.metadata[0].name
  }
  spec {
    access_modes = ["ReadWriteOnce"]
    resources {
      requests = {
        storage = "5Gi"
      }
    }
  }
}

# Desired AdGuard settings — applied by init container on every pod start.
# To change DNS upstreams, filter lists, or rewrites: edit here, terraform apply, then push apps/adguard.yaml.
resource "kubernetes_config_map" "adguard_defaults" {
  metadata {
    name      = "adguard-defaults"
    namespace = kubernetes_namespace.dns.metadata[0].name
  }

  data = {
    "AdGuardHome.yaml" = <<-EOT
      dns:
        bind_hosts:
          - 0.0.0.0
        port: 53
        upstream_dns:
          - https://dns.cloudflare.com/dns-query
          - https://dns.google/dns-query
        bootstrap_dns:
          - 1.1.1.1
          - 8.8.8.8
          - 9.9.9.10
          - 149.112.112.10
        upstream_mode: load_balance
        cache_enabled: true
        cache_size: 4194304
      filters:
        - enabled: true
          url: https://adguardteam.github.io/HostlistsRegistry/assets/filter_1.txt
          name: AdGuard DNS filter
          id: 1
        - enabled: true
          url: https://adguardteam.github.io/HostlistsRegistry/assets/filter_2.txt
          name: AdAway Default Blocklist
          id: 2
        - enabled: true
          url: https://big.oisd.nl/domainswild
          name: OISD Big
          id: 3
        - enabled: true
          url: https://easylist.to/easylist/easylist.txt
          name: EasyList
          id: 4
        - enabled: true
          url: https://easylist.to/easylist/easyprivacy.txt
          name: EasyPrivacy
          id: 5
      tls:
        enabled: true
        server_name: dot.nook.family
        port_dns_over_tls: 853
        certificate_path: /etc/adguard/tls/tls.crt
        private_key_path: /etc/adguard/tls/tls.key
        allow_unencrypted_doh: true
      filtering:
        filtering_enabled: true
        rewrites:
          - domain: '*.nook.family'
            answer: ${var.legion_ip}
            enabled: true
          - domain: '*.neuralplatform.ai'
            answer: ${var.legion_ip}
            enabled: true
    EOT
  }
}

# TLS certificate for DoT — issued via cert-manager DNS-01 (Cloudflare)
resource "kubernetes_manifest" "adguard_dot_cert" {
  manifest = {
    apiVersion = "cert-manager.io/v1"
    kind       = "Certificate"
    metadata = {
      name      = "adguard-dot-tls"
      namespace = kubernetes_namespace.dns.metadata[0].name
    }
    spec = {
      secretName = "adguard-dot-tls"
      issuerRef = {
        name = "letsencrypt-prod"
        kind = "ClusterIssuer"
      }
      dnsNames = ["dot.nook.family"]
    }
  }

  depends_on = [kubernetes_manifest.cluster_issuer_prod]
}

# Deployment + Service managed by Argo CD — see servers/legion/apps/adguard.yaml

resource "kubernetes_ingress_v1" "adguard" {
  metadata {
    name      = "adguard"
    namespace = kubernetes_namespace.dns.metadata[0].name
    annotations = {
      "traefik.ingress.kubernetes.io/router.entrypoints" = "websecure"
      "cert-manager.io/cluster-issuer"                   = "letsencrypt-prod"
    }
  }

  spec {
    tls {
      hosts       = ["dns.nook.family"]
      secret_name = "adguard-tls"
    }

    rule {
      host = "dns.nook.family"
      http {
        path {
          path      = "/"
          path_type = "Prefix"
          backend {
            service {
              name = "adguard-ui"
              port {
                number = 3000
              }
            }
          }
        }
      }
    }
  }

  depends_on = [helm_release.cert_manager]
}

# Host-level bootstrap notes (run bootstrap.sh once on new Legion installs):
# - systemd-resolved disabled (conflicts with AdGuard on port 53)
# - k3s config.yaml includes tls-san for LAN IP
# - /etc/resolv.conf set to 1.1.1.1 fallback
# See: servers/legion/bootstrap.sh