extends Node

signal theme_changed(is_dark: bool)

const Style := preload("res://scripts/ui/ui_style.gd")
const SETTINGS_PATH := "user://settings.cfg"
const SETTINGS_SECTION := "appearance"
const SETTINGS_KEY := "color_scheme"

var _is_dark := true


func _enter_tree() -> void:
	_is_dark = _load_preference()
	Style.set_dark_mode(_is_dark)
	_sync_web_preference()


func is_dark_mode() -> bool:
	return _is_dark


func set_dark_mode(value: bool) -> void:
	if _is_dark == value:
		return
	_is_dark = value
	Style.set_dark_mode(_is_dark)
	_save_preference()
	_sync_web_preference()
	theme_changed.emit(_is_dark)


func toggle_theme() -> void:
	set_dark_mode(not _is_dark)


func _load_preference() -> bool:
	var config := ConfigFile.new()
	if config.load(SETTINGS_PATH) == OK:
		var saved := str(config.get_value(SETTINGS_SECTION, SETTINGS_KEY, ""))
		if saved == "dark" or saved == "light":
			return saved == "dark"
	return _system_prefers_dark()


func _system_prefers_dark() -> bool:
	if OS.has_feature("web"):
		var result: Variant = JavaScriptBridge.eval(
			"window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches",
			true
		)
		return bool(result)
	if DisplayServer.is_dark_mode_supported():
		return DisplayServer.is_dark_mode()
	return true


func _save_preference() -> void:
	var config := ConfigFile.new()
	config.load(SETTINGS_PATH)
	config.set_value(SETTINGS_SECTION, SETTINGS_KEY, "dark" if _is_dark else "light")
	if config.save(SETTINGS_PATH) != OK:
		push_warning("Unable to save color scheme preference.")


func _sync_web_preference() -> void:
	if not OS.has_feature("web"):
		return
	JavaScriptBridge.eval(
		"try { window.localStorage.setItem('medmind-color-scheme', %s); } catch (error) { console.warn('Theme preference storage is unavailable.', error); }" % JSON.stringify(
			"dark" if _is_dark else "light"
		),
		true
	)