package config

import (
	"flag"
	"fmt"
)

// PythonMode 表示 Python runtime 選擇策略。
// M1 階段只保留欄位與 CLI flag，實際切換邏輯由後續 milestone 實作。
type PythonMode string

const (
	PythonModeAuto    PythonMode = "auto"
	PythonModeBundled PythonMode = "bundled"
	PythonModeSystem  PythonMode = "system"
)

type Config struct {
	Port            int
	Host            string
	MockMode        bool
	MockCamera      bool
	MockDeviceCount int
	LogLevel        string
	DevMode         bool
	DataDir         string
	ModelDir        string
	PythonMode      PythonMode
	PythonBin       string // Python 可執行檔路徑（由 Wails 殼層傳入）
}

func Load() *Config {
	cfg := &Config{}
	var pythonMode string

	flag.IntVar(&cfg.Port, "port", 3721, "Server port")
	// 強制 localhost-only：即使使用者傳入其他 host，Load() 結束前會覆寫回 127.0.0.1
	flag.StringVar(&cfg.Host, "host", "127.0.0.1", "Server host (forced to 127.0.0.1 for local-only use)")
	flag.BoolVar(&cfg.MockMode, "mock", false, "Enable mock device driver")
	flag.BoolVar(&cfg.MockCamera, "mock-camera", false, "Enable mock camera")
	flag.IntVar(&cfg.MockDeviceCount, "mock-devices", 1, "Number of mock devices")
	flag.StringVar(&cfg.LogLevel, "log-level", "info", "Log level (debug/info/warn/error)")
	flag.BoolVar(&cfg.DevMode, "dev", false, "Dev mode: disable embedded static file serving")
	flag.StringVar(&cfg.DataDir, "data-dir", "", "Override data directory (default: <binary>/data)")
	flag.StringVar(&cfg.ModelDir, "model-dir", "", "Override custom model directory (default: <data-dir>/custom-models)")
	flag.StringVar(&pythonMode, "python-mode", "auto", "Python runtime strategy: auto|bundled|system (placeholder for M1)")
	flag.StringVar(&cfg.PythonBin, "python", "", "Path to python executable (optional; provided by Wails shell)")
	flag.Parse()

	// 強制 localhost-only
	cfg.Host = "127.0.0.1"

	switch PythonMode(pythonMode) {
	case PythonModeAuto, PythonModeBundled, PythonModeSystem:
		cfg.PythonMode = PythonMode(pythonMode)
	default:
		cfg.PythonMode = PythonModeAuto
	}

	return cfg
}

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