package config

import (
	"encoding/json"
	"fmt"
	"os"
	"time"
)

type Config struct {
	Server   ServerConfig   `json:"server"`
	Database DatabaseConfig `json:"database"`
	Monitor  MonitorConfig  `json:"monitor"`
	SMTP     SMTPConfig     `json:"smtp"`
	Auth     AuthConfig     `json:"auth"`
}

type SMTPConfig struct {
	Host     string `json:"host"`
	Port     int    `json:"port"`
	Username string `json:"username"`
	Password string `json:"password"`
	From     string `json:"from"`
}

type AuthConfig struct {
	AdminUsername     string `json:"admin_username"`
	AdminPasswordHash string `json:"admin_password_hash"`
	JWTSecret         string `json:"jwt_secret"`
}

type ServerConfig struct {
	Addr string `json:"addr"`
}

type DatabaseConfig struct {
	URL string `json:"url"`
}

type MonitorConfig struct {
	Interval string `json:"interval"`
	Timeout  string `json:"timeout"`
}

func Load(path string) (*Config, error) {
	if path == "" {
		path = "config.json"
	}

	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("ler config %s: %w", path, err)
	}

	var cfg Config
	if err := json.Unmarshal(data, &cfg); err != nil {
		return nil, fmt.Errorf("parse config %s: %w", path, err)
	}

	cfg.applyDefaults()
	return &cfg, nil
}

func (c *Config) applyDefaults() {
	if c.Server.Addr == "" {
		c.Server.Addr = ":8080"
	}
	if c.Monitor.Interval == "" {
		c.Monitor.Interval = "60s"
	}
	if c.Monitor.Timeout == "" {
		c.Monitor.Timeout = "10s"
	}
}

func (c *Config) ServerAddr() string {
	if v := os.Getenv("ADDR"); v != "" {
		return v
	}
	return c.Server.Addr
}

func (c *Config) DatabaseURL() string {
	if v := os.Getenv("DATABASE_URL"); v != "" {
		return v
	}
	return c.Database.URL
}

func (c *Config) CheckInterval() time.Duration {
	d, err := time.ParseDuration(c.Monitor.Interval)
	if err != nil {
		return 60 * time.Second
	}
	return d
}

func (c *Config) CheckTimeout() time.Duration {
	d, err := time.ParseDuration(c.Monitor.Timeout)
	if err != nil {
		return 10 * time.Second
	}
	return d
}

func (c *Config) AdminUsername() string {
	if v := os.Getenv("ADMIN_USERNAME"); v != "" {
		return v
	}
	return c.Auth.AdminUsername
}

func (c *Config) AdminPasswordHash() string {
	if v := os.Getenv("ADMIN_PASSWORD_HASH"); v != "" {
		return v
	}
	return c.Auth.AdminPasswordHash
}

func (c *Config) JWTSecret() string {
	if v := os.Getenv("JWT_SECRET"); v != "" {
		return v
	}
	return c.Auth.JWTSecret
}