#!/bin/bash
# Shared primitives for TCP Gateway listener and TCPRoute lifecycle.
#
# Source from component *-lib.sh scripts. Requires _kubectl to be defined
# in the calling context (standard in all catalog component libs).
#
# Functions:
#   _lib_gateway_patch_tcp  <gw_name> <gw_ns> <listener_name> <port>
#   _lib_gateway_remove_tcp <gw_name> <gw_ns> <listener_name>
#   _lib_upsert_tcproute    <route_name> <route_ns> <gw_name> <gw_ns> <section_name> <svc_name> <port>
#   _lib_delete_tcproute    <route_name> <route_ns>

# Upsert a TCP listener on a Gateway. Idempotent.
_lib_gateway_patch_tcp() {
  local gw_name="$1" gw_ns="$2" listener_name="$3" port="$4"

  # kubectl does the lookup server-side (jsonpath filter by name) — the node
  # receives only the matched name, so no JSON parser is needed here.
  local exists=""
  [ -n "$(_kubectl get gateway "$gw_name" -n "$gw_ns" \
      -o "jsonpath={.spec.listeners[?(@.name=='${listener_name}')].name}" 2>/dev/null)" ] \
    && exists="yes"

  if [ "${exists:-no}" = "yes" ]; then
    echo "  [skip] gateway listener ${listener_name} (TCP:${port}) already exists"
    return 0
  fi

  local patch
  patch=$(printf '[{"op":"add","path":"/spec/listeners/-","value":{"name":"%s","port":%s,"protocol":"TCP","allowedRoutes":{"namespaces":{"from":"All"}}}}]' \
    "$listener_name" "$port")
  _kubectl patch gateway "$gw_name" -n "$gw_ns" --type=json -p "$patch"
  echo "  [ok] gateway ${gw_name}: TCP listener ${listener_name} added on port ${port}"
}

# Remove a TCP listener from a Gateway by name. No-op if absent.
_lib_gateway_remove_tcp() {
  local gw_name="$1" gw_ns="$2" listener_name="$3"

  # Find the listener's array index for the JSON-patch path. kubectl streams the
  # names in order (jsonpath range); bash counts to the match — no JSON parser.
  local idx="" _i=0 _n
  while IFS= read -r _n; do
    [ "$_n" = "$listener_name" ] && { idx="$_i"; break; }
    _i=$((_i + 1))
  done < <(_kubectl get gateway "$gw_name" -n "$gw_ns" \
    -o 'jsonpath={range .spec.listeners[*]}{.name}{"\n"}{end}' 2>/dev/null)

  [ -z "$idx" ] && { echo "  [skip] gateway listener ${listener_name} not found"; return 0; }

  _kubectl patch gateway "$gw_name" -n "$gw_ns" --type=json \
    -p "[{\"op\":\"remove\",\"path\":\"/spec/listeners/${idx}\"}]"
  echo "  [ok] gateway ${gw_name}: TCP listener ${listener_name} removed"
}

# Create or replace a TCPRoute routing a Gateway TCP listener to a ClusterIP Service.
_lib_upsert_tcproute() {
  local route_name="$1" route_ns="$2" gw_name="$3" gw_ns="$4" section_name="$5" svc_name="$6" port="$7"

  _kubectl apply -f - <<ROUTE
apiVersion: gateway.networking.k8s.io/v1alpha2
kind: TCPRoute
metadata:
  name: ${route_name}
  namespace: ${route_ns}
  labels:
    app.kubernetes.io/managed-by: provisioning
spec:
  parentRefs:
    - name: ${gw_name}
      namespace: ${gw_ns}
      sectionName: ${section_name}
  rules:
    - backendRefs:
        - name: ${svc_name}
          port: ${port}
ROUTE
  echo "  [ok] TCPRoute ${route_ns}/${route_name} → ${svc_name}:${port} via ${gw_name}/${section_name}"
}

# Delete a TCPRoute. No-op if absent.
_lib_delete_tcproute() {
  local route_name="$1" route_ns="$2"
  _kubectl delete tcproute/"${route_name}" --namespace "${route_ns}" --ignore-not-found
  echo "  [ok] TCPRoute ${route_ns}/${route_name} deleted (if existed)"
}