// Command server 启动 sundynix-gateway —— 第 2 层业务网关 / 统一接入层。
package main

import (
	"context"
	"log"
	"os"

	"github.com/sundynix/sundynix-gateway/internal/nats"
	"github.com/sundynix/sundynix-gateway/internal/router"
	"github.com/sundynix/sundynix-gateway/internal/store"
	"github.com/sundynix/sundynix-shared/contract"
)

func main() {
	natsURL := envOr("NATS_URL", "nats://localhost:4222")
	pgDSN := envOr("POSTGRES_DSN", "postgres://sundynix:sundynix@localhost:5432/sundynix?sslmode=disable")
	redisAddr := envOr("REDIS_ADDR", "localhost:6379")

	db := store.OpenPostgres(pgDSN) // MainDB: Users / Billing / DSL（连不上则降级）
	defer db.Close()
	cache := store.OpenRedis(redisAddr) // CacheDB: Session / Rate Limit（连不上则降级）
	defer cache.Close()
	bus := nats.MustConnect(natsURL) // 接入 NATS 零拷贝骨干网 + 声明任务流
	defer bus.Close()

	// 配置控制面：响应 Dispatcher 对当前激活模型配置的请求。
	if _, err := bus.ServeModelConfig(func() *contract.ModelConfig {
		row, _ := db.GetActiveModel(context.Background())
		if row == nil {
			return nil
		}
		return &contract.ModelConfig{Provider: row.Provider, BaseURL: row.BaseURL, APIKey: row.APIKey, Model: row.Model}
	}); err != nil {
		log.Printf("[gateway] serve model config: %v", err)
	}

	r := router.New(db, cache, bus)
	addr := envOr("GATEWAY_ADDR", ":8080")
	log.Printf("[gateway] listening on %s", addr)
	if err := r.Run(addr); err != nil {
		log.Fatalf("[gateway] exit: %v", err)
	}
}

func envOr(key, def string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return def
}