package config

import (
	"flag"
	"fmt"
	"log"
	"os"
	"strconv"
	"time"
)

// DatabaseConfig 数据库配置
type DatabaseConfig struct {
	Host, Password, DBName, SSLMode, TimeZone string
	Port                                         int
	User                                         string
	Schema                                       string
}

// RedisConfig Redis 配置（与项目其他服务一致：host/port/db/password）
type RedisConfig struct {
	Host     string
	Port     int
	DB       int
	Password string
}

// URL 构造 redis:// URL（pkg/redis 客户端使用）
func (r *RedisConfig) URL() string {
	auth := ""
	if r.Password != "" {
		auth = r.Password + "@"
	}
	return fmt.Sprintf("redis://%s%s:%d/%d", auth, r.Host, r.Port, r.DB)
}

// RefreshIntervals 物化视图/预聚表刷新间隔
type RefreshIntervals struct {
	DailyUserIncome        time.Duration
	DailyExhibitionRevenue time.Duration
	DailyLikeIncome        time.Duration
	AssetLevelDistribution time.Duration
	WeeklyUserIncome       time.Duration
	UpcomingLevelUps       time.Duration
}

// ChannelConfig 事件 channel 配置
type ChannelConfig struct {
	EventChannelCapacity int
	EventWorkerCount     int
	EventBatchSize       int
	EventBatchInterval   time.Duration
}

// PartitionConfig 分区管理配置
type PartitionConfig struct {
	RetentionDays int
	PreCreateDays int
}

// ExtensionConfig 预留扩展开关
type ExtensionConfig struct {
	EnableOLAPDualWrite   bool
	EnableRealtimeChannel bool
	EnableSDKEndpoint     bool
	EnableSampling        bool
}

var (
	DBConfig = &DatabaseConfig{
		Schema: "statistic",
	}
	RedisCfg = &RedisConfig{
		Host:     "localhost",
		Port:     6379,
		DB:       0,
		Password: "",
	}
	RefreshCfg = &RefreshIntervals{
		DailyUserIncome:        5 * time.Minute,
		DailyExhibitionRevenue: 5 * time.Minute,
		DailyLikeIncome:        5 * time.Minute,
		AssetLevelDistribution: 15 * time.Minute,
		WeeklyUserIncome:       5 * time.Minute,
		UpcomingLevelUps:       15 * time.Minute,
	}
	ChannelCfg = &ChannelConfig{
		EventChannelCapacity: 1000,
		EventWorkerCount:     1,
		EventBatchSize:       100,
		EventBatchInterval:   1 * time.Second,
	}
	PartitionCfg = &PartitionConfig{
		RetentionDays: 30,
		PreCreateDays: 7,
	}
	ExtCfg = &ExtensionConfig{ // 全部默认 false（本期不启用）
		EnableOLAPDualWrite:   false,
		EnableRealtimeChannel: false,
		EnableSDKEndpoint:     false,
		EnableSampling:        false,
	}
)

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

func getEnvInt(key string, fallback int) int {
	if v := os.Getenv(key); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			return n
		}
	}
	return fallback
}

func getEnvDuration(key string, fallback time.Duration) time.Duration {
	if v := os.Getenv(key); v != "" {
		if d, err := time.ParseDuration(v); err == nil {
			return d
		}
	}
	return fallback
}

func getEnvBool(key string, fallback bool) bool {
	if v := os.Getenv(key); v != "" {
		if b, err := strconv.ParseBool(v); err == nil {
			return b
		}
	}
	return fallback
}

// InitConfig 初始化所有配置（flag + 环境变量）
func InitConfig() {
	flag.StringVar(&DBConfig.Host, "db-host", getEnv("STATISTIC_DB_HOST", "localhost"), "数据库主机")
	flag.IntVar(&DBConfig.Port, "db-port", getEnvInt("STATISTIC_DB_PORT", 5432), "数据库端口")
	flag.StringVar(&DBConfig.User, "db-user", getEnv("STATISTIC_DB_USER", "postgres"), "数据库用户")
	flag.StringVar(&DBConfig.Password, "db-password", getEnv("STATISTIC_DB_PASSWORD", ""), "数据库密码")
	flag.StringVar(&DBConfig.DBName, "db-name", getEnv("STATISTIC_DB_NAME", "topfans"), "数据库名")
	flag.StringVar(&DBConfig.SSLMode, "db-sslmode", "disable", "数据库 SSL 模式")
	flag.StringVar(&DBConfig.Schema, "db-schema", getEnv("STATISTIC_DB_SCHEMA", "statistic"), "数据库 schema")

	flag.StringVar(&RedisCfg.Host, "redis-host", getEnv("STATISTIC_REDIS_HOST", "localhost"), "Redis 主机")
	flag.IntVar(&RedisCfg.Port, "redis-port", getEnvInt("STATISTIC_REDIS_PORT", 6379), "Redis 端口")
	flag.IntVar(&RedisCfg.DB, "redis-db", getEnvInt("STATISTIC_REDIS_DB", 0), "Redis DB")
	flag.StringVar(&RedisCfg.Password, "redis-password", getEnv("STATISTIC_REDIS_PASSWORD", ""), "Redis 密码")

	flag.IntVar(&ChannelCfg.EventChannelCapacity, "event-channel-capacity", getEnvInt("STATISTIC_EVENT_CHANNEL_CAPACITY", 1000), "事件 channel 容量")
	flag.IntVar(&ChannelCfg.EventBatchSize, "event-batch-size", getEnvInt("STATISTIC_EVENT_BATCH_SIZE", 100), "事件批量大小")
	flag.DurationVar(&ChannelCfg.EventBatchInterval, "event-batch-interval", getEnvDuration("STATISTIC_EVENT_BATCH_INTERVAL", time.Second), "事件批量间隔")

	flag.IntVar(&PartitionCfg.RetentionDays, "partition-retention-days", getEnvInt("STATISTIC_PARTITION_RETENTION_DAYS", 30), "分区保留天数")
	flag.IntVar(&PartitionCfg.PreCreateDays, "partition-precreate-days", getEnvInt("STATISTIC_PARTITION_PRECREATE_DAYS", 7), "分区预创建天数")

	flag.BoolVar(&ExtCfg.EnableOLAPDualWrite, "enable-olap", getEnvBool("STATISTIC_ENABLE_OLAP_DUAL_WRITE", false), "启用 OLAP 双写")
	flag.BoolVar(&ExtCfg.EnableRealtimeChannel, "enable-realtime", getEnvBool("STATISTIC_ENABLE_REALTIME_CHANNEL", false), "启用实时通道")
	flag.BoolVar(&ExtCfg.EnableSDKEndpoint, "enable-sdk", getEnvBool("STATISTIC_ENABLE_SDK_ENDPOINT", false), "启用 SDK 端点")
	flag.BoolVar(&ExtCfg.EnableSampling, "enable-sampling", getEnvBool("STATISTIC_ENABLE_SAMPLING", false), "启用采样")

	flag.Parse()
	log.Println("statisticService 配置初始化完成")
	log.Printf("  数据库: %s:%d/%s (schema=%s)", DBConfig.Host, DBConfig.Port, DBConfig.DBName, DBConfig.Schema)
	log.Printf("  Redis: %s", RedisCfg.URL())
	log.Printf("  事件 channel 容量: %d, 批量: %d/%v", ChannelCfg.EventChannelCapacity, ChannelCfg.EventBatchSize, ChannelCfg.EventBatchInterval)
	log.Printf("  分区保留: %d 天, 预创建: %d 天", PartitionCfg.RetentionDays, PartitionCfg.PreCreateDays)
	log.Printf("  扩展开关: OLAP=%v Realtime=%v SDK=%v Sampling=%v",
		ExtCfg.EnableOLAPDualWrite, ExtCfg.EnableRealtimeChannel, ExtCfg.EnableSDKEndpoint, ExtCfg.EnableSampling)
}