package config

import (
	"encoding/json"
	"os"
	"path/filepath"
	"runtime"
)

type Config struct {
	ServerURL    string `json:"server_url"`
	EnrollmentToken string `json:"enrollment_token,omitempty"`
	DeviceID     string `json:"device_id"`
	Credential   string `json:"credential"`
	Label        string `json:"label"`
	HeartbeatSec int    `json:"heartbeat_interval_seconds"`
}

func configDir() string {
	switch runtime.GOOS {
	case "windows":
		if p := os.Getenv("ProgramData"); p != "" {
			return filepath.Join(p, "FleetForge")
		}
		return `C:\ProgramData\FleetForge`
	case "darwin":
		home, _ := os.UserHomeDir()
		return filepath.Join(home, "Library", "Application Support", "FleetForge")
	default:
		home, _ := os.UserHomeDir()
		return filepath.Join(home, ".config", "forge-agent")
	}
}

func ConfigPath() string {
	return filepath.Join(configDir(), "config.json")
}

func Load() (*Config, error) {
	data, err := os.ReadFile(ConfigPath())
	if err != nil {
		return nil, err
	}
	var cfg Config
	if err := json.Unmarshal(data, &cfg); err != nil {
		return nil, err
	}
	if cfg.HeartbeatSec <= 0 {
		cfg.HeartbeatSec = 30
	}
	return &cfg, nil
}

func Save(cfg *Config) error {
	dir := filepath.Dir(ConfigPath())
	if err := os.MkdirAll(dir, 0700); err != nil {
		return err
	}
	data, err := json.MarshalIndent(cfg, "", "  ")
	if err != nil {
		return err
	}
	return os.WriteFile(ConfigPath(), data, 0600)
}

func Delete() error {
	return os.Remove(ConfigPath())
}