package main

import (
	"context"
	"database/sql"
	"errors"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/joho/godotenv"
	_ "github.com/luxsin/app-api/docs"
	"github.com/luxsin/app-api/internal/cache"
	"github.com/luxsin/app-api/internal/config"
	"github.com/luxsin/app-api/internal/database"
	"github.com/luxsin/app-api/internal/model"
	"github.com/luxsin/app-api/internal/repository"
	"github.com/luxsin/app-api/internal/router"
	"github.com/luxsin/app-api/internal/search"
	"github.com/luxsin/app-api/internal/storage"
	"github.com/luxsin/app-api/internal/task"
	"github.com/luxsin/app-api/pkg/logger"
	"github.com/redis/go-redis/v9"
	"go.uber.org/zap"
)

//	@title			App Audio API
//	@version		1.0
//	@description	耳机音频参数 EQ 后端服务
//
//	@BasePath		/
//
//	@contact.name	Luxsin

func main() {
	_ = godotenv.Load()

	cfg, err := config.Load()
	if err != nil {
		panic(err)
	}

	if cfg.Env == "production" {
		gin.SetMode(gin.ReleaseMode)
	}

	log, err := logger.New(cfg.Env)
	if err != nil {
		panic(err)
	}
	defer log.Sync() //nolint:errcheck

	db, err := database.Open(cfg.Database)
	if err != nil {
		log.Fatal("database connect failed", zap.Error(err))
	}
	defer db.Close()

	log.Info("database connected",
		zap.String("host", cfg.Database.Host),
		zap.Int("port", cfg.Database.Port),
		zap.String("database", cfg.Database.Name),
	)

	searchClient := search.NewClient(cfg.Meilisearch)
	log.Info("meilisearch configured",
		zap.String("host", cfg.Meilisearch.Host),
		zap.String("index", cfg.Meilisearch.Index),
	)

	rdb := cache.NewClient(cfg.Redis)
	defer rdb.Close()
	log.Info("redis connected",
		zap.String("host", cfg.Redis.Host),
		zap.Int("port", cfg.Redis.Port),
		zap.Int("db", cfg.Redis.Database),
	)
	log.Info("share code ttl configured", zap.Duration("ttl", cfg.ShareCodeTTL))

	// 启动时预热缓存
	warmUpCache(log, db, rdb)

	// 启动定时刷入任务：每 5 分钟从 Redis 刷入数据库（仅 ENABLE_PERSIST_TASK=true 的容器运行）
	if cfg.EnablePersistTask {
		deviceRepo := repository.NewDeviceRepository(db)
		devicePersistTask := task.NewDevicePersistTask(rdb, deviceRepo, log)
		devicePersistTask.Start(5 * time.Minute)

		shareCodeCache := cache.NewShareCodeCache(rdb, cfg.ShareCodeTTL)
		shareCodeRepo := repository.NewShareCodeRepository(db)
		shareCodePersistTask := task.NewShareCodePersistTask(shareCodeCache, shareCodeRepo, log)
		shareCodePersistTask.Start(5 * time.Minute)
	} else {
		log.Info("device persist task disabled")
	}

	s3Storage, err := storage.NewS3Storage(context.Background(), cfg.S3)
	if err != nil {
		log.Fatal("s3 client init failed", zap.Error(err))
	}
	log.Info("s3 configured",
		zap.String("bucket", cfg.S3.Bucket),
		zap.String("region", cfg.S3.Region),
	)

	engine := router.New(log, db, searchClient, rdb, cfg.Equalize, s3Storage, cfg.ShareCodeMaxPerMac, cfg.ShareCodeTTL, cfg.Env)

	srv := &http.Server{
		Addr:         cfg.Addr(),
		Handler:      engine,
		ReadTimeout:  10 * time.Second,
		WriteTimeout: 30 * time.Second,
		IdleTimeout:  60 * time.Second,
	}

	go func() {
		log.Info("server starting", zap.String("addr", cfg.Addr()), zap.String("env", cfg.Env))
		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
			log.Fatal("server failed", zap.Error(err))
		}
	}()

	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit

	log.Info("server shutting down")

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	if err := srv.Shutdown(ctx); err != nil {
		log.Fatal("server shutdown failed", zap.Error(err))
	}

	log.Info("server stopped")
}

// warmUpCache 启动时从数据库加载数据到 Redis（缓存已存在则跳过，避免多实例重复预热）
func warmUpCache(log *zap.Logger, db *sql.DB, rdb *redis.Client) {
	ctx := context.Background()

	brandCache := cache.NewBrandCache(rdb)
	modelCache := cache.NewModelCache(rdb)

	brandExists, err := brandCache.Exists(ctx)
	if err != nil {
		log.Warn("check brand cache failed, will warm up", zap.Error(err))
	}
	modelExists, err := modelCache.Exists(ctx)
	if err != nil {
		log.Warn("check model cache failed, will warm up", zap.Error(err))
	}
	if brandExists && modelExists {
		log.Info("cache already warmed, skip warm-up")
		return
	}

	brandRepo := repository.NewBrandRepository(db, brandCache)
	modelRepo := repository.NewModelRepository(db, modelCache)

	// 预热 brand:all
	if brands, err := brandRepo.ListFromDB(ctx, ""); err != nil {
		log.Warn("brand warm-up failed", zap.Error(err))
	} else if err := brandCache.SetAll(ctx, brands); err != nil {
		log.Warn("brand cache set failed", zap.Error(err))
	} else {
		log.Info("brand cache warmed up", zap.Int("count", len(brands)))
	}

	// 预热 model:all + model:brand:{brandName}
	if allModels, err := modelRepo.ListAllFromDB(ctx); err != nil {
		log.Warn("model warm-up failed", zap.Error(err))
	} else if err := modelCache.SetAll(ctx, allModels); err != nil {
		log.Warn("model cache set failed", zap.Error(err))
	} else {
		log.Info("model cache warmed up", zap.Int("count", len(allModels)))

		// 按品牌分组预热 model:brand:{brandName}
		grouped := groupModelsByBrand(allModels)
		for brandName, models := range grouped {
			if err := modelCache.SetByBrand(ctx, brandName, models); err != nil {
				log.Warn("model brand cache set failed", zap.String("brand", brandName), zap.Error(err))
			}
		}
		log.Info("model brand cache warmed up", zap.Int("brands", len(grouped)))
	}
}

// groupModelsByBrand 按品牌分组型号列表
func groupModelsByBrand(models []model.Model) map[string][]model.Model {
	result := make(map[string][]model.Model)
	for _, m := range models {
		result[m.BrandName] = append(result[m.BrandName], m)
	}
	return result
}