package config

import (
	"fmt"
	"time"

	"github.com/spf13/viper"
)

type Config struct {
	Server   ServerConfig   `mapstructure:"server"`
	Database DatabaseConfig `mapstructure:"database"`
	Redis    RedisConfig    `mapstructure:"redis"`
	JWT      JWTConfig      `mapstructure:"jwt"`
	WeChat   WeChatConfig   `mapstructure:"wechat"`
	Upload   UploadConfig   `mapstructure:"upload"`
}

type ServerConfig struct {
	Host string `mapstructure:"host"`
	Port int    `mapstructure:"port"`
}

type DatabaseConfig struct {
	Host         string `mapstructure:"host"`
	Port         int    `mapstructure:"port"`
	Username     string `mapstructure:"username"`
	Password     string `mapstructure:"password"`
	Database     string `mapstructure:"database"`
	MaxOpenConns int    `mapstructure:"max_open_conns"`
	MaxIdleConns int    `mapstructure:"max_idle_conns"`
}

func (d *DatabaseConfig) DSN() string {
	return fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8mb4&parseTime=True&loc=Local",
		d.Username, d.Password, d.Host, d.Port, d.Database)
}

type RedisConfig struct {
	Host     string `mapstructure:"host"`
	Port     int    `mapstructure:"port"`
	Password string `mapstructure:"password"`
	DB       int    `mapstructure:"db"`
}

func (r *RedisConfig) Addr() string {
	return fmt.Sprintf("%s:%d", r.Host, r.Port)
}

type JWTConfig struct {
	Secret          string        `mapstructure:"secret"`
	AccessTokenTTL  time.Duration `mapstructure:"access_token_ttl"`
	RefreshTokenTTL time.Duration `mapstructure:"refresh_token_ttl"`
}

type WeChatConfig struct {
	AppID       string `mapstructure:"app_id"`
	AppSecret   string `mapstructure:"app_secret"`
	MchID       string `mapstructure:"mch_id"`
	ApiKey      string `mapstructure:"api_key"`
	NotifyURL   string `mapstructure:"notify_url"`
	CertPath    string `mapstructure:"cert_path"`
	CertContent string `mapstructure:"cert_content"`
}

type UploadConfig struct {
	Path      string `mapstructure:"path"`
	MaxSize   int64  `mapstructure:"max_size"`
	ChunkPath string `mapstructure:"chunk_path"`
}

var GlobalConfig *Config

func LoadConfig(path string) (*Config, error) {
	viper.SetConfigFile(path)
	viper.SetConfigType("yaml")

	viper.SetDefault("server.host", "0.0.0.0")
	viper.SetDefault("server.port", 8080)
	viper.SetDefault("database.max_open_conns", 100)
	viper.SetDefault("database.max_idle_conns", 10)
	viper.SetDefault("jwt.access_token_ttl", "24h")
	viper.SetDefault("jwt.refresh_token_ttl", "7d")
	viper.SetDefault("upload.max_size", 52428800) // 50MB
	viper.SetDefault("upload.chunk_path", "./uploads/chunks")

	if err := viper.ReadInConfig(); err != nil {
		return nil, fmt.Errorf("failed to read config: %w", err)
	}

	var cfg Config
	if err := viper.Unmarshal(&cfg); err != nil {
		return nil, fmt.Errorf("failed to unmarshal config: %w", err)
	}

	GlobalConfig = &cfg
	return &cfg, nil
}