#!/bin/sh
# После recreate api-gateway Docker выдаёт новый IP; без reload nginx шлёт на старый адрес → 502.
set -eu

GW_HOST="${IDP_API_GATEWAY_HOST:-lendry-id-api-gateway}"
GW_PORT="${IDP_API_GATEWAY_PORT:-3000}"
WATCH_INTERVAL="${IDP_NGINX_WATCH_INTERVAL:-5}"

log() {
  echo "[idp-nginx-watch] $*"
}

wait_for_gateway() {
  attempt=0
  while [ "$attempt" -lt 120 ]; do
    if wget -qO- --timeout=3 "http://${GW_HOST}:${GW_PORT}/health" 2>/dev/null | grep -q '"status"'; then
      log "api-gateway доступен (${GW_HOST}:${GW_PORT})"
      return 0
    fi
    attempt=$((attempt + 1))
    sleep 1
  done
  log "WARN: api-gateway не ответил за 120с — nginx стартует без ожидания"
  return 0
}

watch_gateway() {
  last_ip=""
  while true; do
    sleep "$WATCH_INTERVAL"
    current_ip="$(getent hosts "$GW_HOST" 2>/dev/null | awk '{print $1}' | head -n1 || true)"
    healthy=0
    if wget -qO- --timeout=3 "http://${GW_HOST}:${GW_PORT}/health" 2>/dev/null | grep -q '"status"'; then
      healthy=1
    fi
    if [ "$healthy" -eq 0 ]; then
      log "api-gateway недоступен — reload nginx"
      nginx -s reload 2>/dev/null || true
      continue
    fi
    if [ -n "$current_ip" ] && [ -n "$last_ip" ] && [ "$current_ip" != "$last_ip" ]; then
      log "IP ${GW_HOST} изменился (${last_ip} → ${current_ip}) — reload nginx"
      nginx -s reload 2>/dev/null || true
    fi
    if [ -n "$current_ip" ]; then
      last_ip="$current_ip"
    fi
  done
}

wait_for_gateway
watch_gateway &