package config

import (
	"errors"
	"fmt"
	"os"
	"strings"

	"github.com/spf13/viper"
)

type AMapConfig struct {
	Key string `mapstructure:"key"`
}

type Config struct {
	AMap     AMapConfig     `mapstructure:"amap"`
	Server   ServerConfig   `mapstructure:"server"`
	Postgres PostgresConfig `mapstructure:"postgres"`
	MinIO    MinIOConfig    `mapstructure:"minio"`
	JWT      JWTConfig      `mapstructure:"jwt"`
	WeChat   WeChatConfig   `mapstructure:"wechat"`
	Auth     AuthConfig     `mapstructure:"auth"`
	Admin    AdminConfig    `mapstructure:"admin"`
}

type ServerConfig struct {
	Port int    `mapstructure:"port"`
	Mode string `mapstructure:"mode"`
}

type PostgresConfig struct {
	Host     string `mapstructure:"host"`
	Port     int    `mapstructure:"port"`
	User     string `mapstructure:"user"`
	Password string `mapstructure:"password"`
	Database string `mapstructure:"database"`
	SSLMode  string `mapstructure:"ssl_mode"`
}

func (p PostgresConfig) DSN() string {
	return fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=%s TimeZone=Asia/Shanghai",
		p.Host, p.Port, p.User, p.Password, p.Database, p.SSLMode)
}

type MinIOConfig struct {
	Endpoint  string `mapstructure:"endpoint"`
	AccessKey string `mapstructure:"access_key"`
	SecretKey string `mapstructure:"secret_key"`
	Bucket    string `mapstructure:"bucket"`
	UseSSL    bool   `mapstructure:"use_ssl"`
}

type JWTConfig struct {
	Secret       string `mapstructure:"secret"`
	ExpireHours  int    `mapstructure:"expire_hours"`
	RefreshHours int    `mapstructure:"refresh_hours"`
}

type WeChatConfig struct {
	AppID     string `mapstructure:"app_id"`
	AppSecret string `mapstructure:"app_secret"`
}

type AuthConfig struct {
	DevLogin bool `mapstructure:"dev_login"`
}

type AdminConfig struct {
	Username string `mapstructure:"username"`
	Password string `mapstructure:"password"`
}

func Load() (*Config, error) {
	v := viper.New()
	v.SetDefault("amap.key", "")
	v.SetDefault("server.port", 9090)
	v.SetDefault("server.mode", "debug")
	v.SetDefault("postgres.host", "192.168.100.127")
	v.SetDefault("postgres.port", 5432)
	v.SetDefault("postgres.user", "root")
	v.SetDefault("postgres.password", "")
	v.SetDefault("postgres.database", "sundynix-pets")
	v.SetDefault("postgres.ssl_mode", "disable")
	v.SetDefault("minio.endpoint", "https://s3.sundynix.cn")
	v.SetDefault("minio.access_key", "")
	v.SetDefault("minio.secret_key", "")
	v.SetDefault("minio.bucket", "sundynix-pet")
	v.SetDefault("minio.use_ssl", true)
	v.SetDefault("jwt.secret", "")
	v.SetDefault("jwt.expire_hours", 2)
	v.SetDefault("jwt.refresh_hours", 2)
	v.SetDefault("wechat.app_id", "")
	v.SetDefault("wechat.app_secret", "")
	v.SetDefault("auth.dev_login", false)
	v.SetDefault("admin.username", "sundynix")
	v.SetDefault("admin.password", "")

	v.SetConfigName("config")
	v.SetConfigType("yaml")
	v.AddConfigPath("./configs")
	v.AddConfigPath("../../configs")
	v.SetEnvPrefix("PETS")
	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
	v.AutomaticEnv()
	if err := v.ReadInConfig(); err != nil {
		var missing viper.ConfigFileNotFoundError
		if !errors.As(err, &missing) && !os.IsNotExist(err) {
			return nil, fmt.Errorf("read config: %w", err)
		}
	}
	var cfg Config
	if err := v.Unmarshal(&cfg); err != nil {
		return nil, fmt.Errorf("decode config: %w", err)
	}
	if cfg.Postgres.Password == "" || cfg.JWT.Secret == "" {
		return nil, errors.New("postgres.password and jwt.secret are required")
	}
	if cfg.MinIO.AccessKey == "" || cfg.MinIO.SecretKey == "" {
		return nil, errors.New("minio access_key and secret_key are required")
	}
	if cfg.Server.Mode == "release" && cfg.Auth.DevLogin {
		return nil, errors.New("dev login must be disabled in release mode")
	}
	// Access tokens have the same fixed two-hour lifetime for both clients.
	cfg.JWT.ExpireHours = 2
	cfg.JWT.RefreshHours = 2
	return &cfg, nil
}