extends Control
## Login screen controller - handles authentication UI

# Login panel elements
@onready var guest_button := %GuestButton as Button
@onready var email_input := %EmailInput as LineEdit
@onready var password_input := %PasswordInput as LineEdit
@onready var remember_me := %RememberMe as CheckBox
@onready var login_button := %LoginButton as Button
@onready var register_link := %RegisterLink as LinkButton
@onready var google_button := %GoogleButton as Button
@onready var apple_button := %AppleButton as Button
@onready var facebook_button := %FacebookButton as Button
@onready var status_label := %StatusLabel as Label
@onready var loading_spinner := %LoadingSpinner as TextureProgressBar

# Registration panel elements
@onready var registration_panel := %RegistrationPanel as PanelContainer
@onready var reg_email_input := %RegEmailInput as LineEdit
@onready var reg_username_input := %RegUsernameInput as LineEdit
@onready var reg_password_input := %RegPasswordInput as LineEdit
@onready var reg_confirm_password_input := %RegConfirmPasswordInput as LineEdit
@onready var password_strength := %PasswordStrength as ProgressBar
@onready var password_hint := %PasswordHint as Label
@onready var register_button := %RegisterButton as Button
@onready var back_to_login_link := %BackToLoginLink as LinkButton
@onready var reg_status_label := %RegStatusLabel as Label

# Main panel reference
@onready var main_panel := $CenterContainer/MainPanel as PanelContainer

var is_loading: bool = false

func _ready() -> void:
	_connect_signals()
	_setup_ui()
	
	# Check if already authenticated
	if AuthManager.is_logged_in():
		_go_to_lobby()

func _connect_signals() -> void:
	# Login buttons
	guest_button.pressed.connect(_on_guest_pressed)
	login_button.pressed.connect(_on_login_pressed)
	register_link.pressed.connect(_show_registration)
	
	# Social buttons
	google_button.pressed.connect(_on_google_pressed)
	apple_button.pressed.connect(_on_apple_pressed)
	facebook_button.pressed.connect(_on_facebook_pressed)
	
	# Registration buttons
	register_button.pressed.connect(_on_register_pressed)
	back_to_login_link.pressed.connect(_show_login)
	
	# Password strength checker
	reg_password_input.text_changed.connect(_check_password_strength)
	
	# Auth manager signals
	AuthManager.auth_started.connect(_on_auth_started)
	AuthManager.auth_completed.connect(_on_auth_completed)
	AuthManager.auth_failed.connect(_on_auth_failed)
	AuthManager.session_restored.connect(_on_session_restored)
	
	# Enter key to submit
	password_input.text_submitted.connect(func(_t): _on_login_pressed())
	reg_confirm_password_input.text_submitted.connect(func(_t): _on_register_pressed())

func _setup_ui() -> void:
	status_label.text = ""
	reg_status_label.text = ""
	loading_spinner.visible = false
	registration_panel.visible = false
	main_panel.visible = true
	
	# Hide social buttons on platforms where they're not supported
	_configure_social_buttons()

func _configure_social_buttons() -> void:
	# Google - available on all platforms
	google_button.visible = true
	
	# Apple - iOS and macOS only (or hide if not configured)
	var os := OS.get_name()
	apple_button.visible = os in ["iOS", "macOS"]
	
	# Facebook - available on all platforms
	facebook_button.visible = true

# =============================================================================
# Panel Switching
# =============================================================================

func _show_registration() -> void:
	main_panel.visible = false
	registration_panel.visible = true
	reg_status_label.text = ""
	reg_email_input.grab_focus()

func _show_login() -> void:
	registration_panel.visible = false
	main_panel.visible = true
	status_label.text = ""
	email_input.grab_focus()

# =============================================================================
# Login Handlers
# =============================================================================

func _on_guest_pressed() -> void:
	if is_loading:
		return
	AuthManager.login_as_guest()

func _on_login_pressed() -> void:
	if is_loading:
		return
	
	var email := email_input.text.strip_edges()
	var password := password_input.text
	
	if email.is_empty():
		_show_error("Please enter your email")
		return
	
	if password.is_empty():
		_show_error("Please enter your password")
		return
	
	if not _is_valid_email(email):
		_show_error("Please enter a valid email address")
		return
	
	AuthManager.login_with_email(email, password, remember_me.button_pressed)

func _on_google_pressed() -> void:
	if is_loading:
		return
	
	# Note: Actual Google Sign-In requires platform-specific implementation
	# This is a placeholder - you need to integrate Google Sign-In SDK
	_show_error("Google Sign-In requires SDK integration")
	
	# When you have the ID token from Google SDK:
	# AuthManager.login_with_google(id_token)

func _on_apple_pressed() -> void:
	if is_loading:
		return
	
	# Note: Apple Sign-In requires platform-specific implementation
	_show_error("Apple Sign-In requires SDK integration")
	
	# When you have the ID token from Apple:
	# AuthManager.login_with_apple(id_token)

func _on_facebook_pressed() -> void:
	if is_loading:
		return
	
	# Note: Facebook Login requires platform-specific implementation
	_show_error("Facebook Login requires SDK integration")
	
	# When you have the access token from Facebook SDK:
	# AuthManager.login_with_facebook(access_token)

# =============================================================================
# Registration Handlers
# =============================================================================

func _on_register_pressed() -> void:
	if is_loading:
		return
	
	var email := reg_email_input.text.strip_edges()
	var username := reg_username_input.text.strip_edges()
	var password := reg_password_input.text
	var confirm_password := reg_confirm_password_input.text
	
	# Validation
	if email.is_empty():
		_show_reg_error("Please enter your email")
		return
	
	if not _is_valid_email(email):
		_show_reg_error("Please enter a valid email address")
		return
	
	if username.is_empty():
		_show_reg_error("Please enter a username")
		return
	
	if username.length() < 3:
		_show_reg_error("Username must be at least 3 characters")
		return
	
	if password.is_empty():
		_show_reg_error("Please enter a password")
		return
	
	if password.length() < 8:
		_show_reg_error("Password must be at least 8 characters")
		return
	
	if password != confirm_password:
		_show_reg_error("Passwords do not match")
		return
	
	if _calculate_password_strength(password) < 2:
		_show_reg_error("Password is too weak. Add numbers or symbols.")
		return
	
	AuthManager.register_with_email(email, password, username)

func _check_password_strength(password: String) -> void:
	var strength := _calculate_password_strength(password)
	password_strength.value = strength
	
	# Color based on strength
	var color: Color
	match strength:
		0, 1:
			color = Color.RED
			password_hint.text = "Weak - add more characters"
		2:
			color = Color.ORANGE
			password_hint.text = "Fair - add numbers or symbols"
		3:
			color = Color.YELLOW_GREEN
			password_hint.text = "Good"
		4:
			color = Color.GREEN
			password_hint.text = "Strong!"
	
	# Apply color to progress bar
	var style := StyleBoxFlat.new()
	style.bg_color = color
	password_strength.add_theme_stylebox_override("fill", style)

func _calculate_password_strength(password: String) -> int:
	var strength := 0
	
	if password.length() >= 8:
		strength += 1
	if password.length() >= 12:
		strength += 1
	
	var has_upper := false
	var has_lower := false
	var has_digit := false
	var has_special := false
	
	for c in password:
		if c.to_upper() != c.to_lower():
			if c == c.to_upper():
				has_upper = true
			else:
				has_lower = true
		elif c.is_valid_int():
			has_digit = true
		else:
			has_special = true
	
	if has_upper and has_lower:
		strength += 1
	if has_digit:
		strength += 0.5
	if has_special:
		strength += 0.5
	
	return mini(int(strength), 4)

# =============================================================================
# Auth Manager Callbacks
# =============================================================================

func _on_auth_started() -> void:
	is_loading = true
	loading_spinner.visible = true
	_set_inputs_enabled(false)
	status_label.text = ""
	reg_status_label.text = ""

func _on_auth_completed(success: bool, _user_data: Dictionary) -> void:
	# Check if node is still in tree (may have been freed during scene transition)
	if not is_inside_tree():
		return
	
	is_loading = false
	loading_spinner.visible = false
	_set_inputs_enabled(true)
	
	if success:
		_go_to_lobby()

func _on_auth_failed(error: String) -> void:
	is_loading = false
	loading_spinner.visible = false
	_set_inputs_enabled(true)
	
	if registration_panel.visible:
		_show_reg_error(error)
	else:
		_show_error(error)

func _on_session_restored() -> void:
	if not is_inside_tree():
		return
	_go_to_lobby()

# =============================================================================
# Helper Functions
# =============================================================================

func _show_error(message: String) -> void:
	status_label.text = message
	status_label.add_theme_color_override("font_color", Color(1, 0.4, 0.4))

func _show_reg_error(message: String) -> void:
	reg_status_label.text = message
	reg_status_label.add_theme_color_override("font_color", Color(1, 0.4, 0.4))

func _set_inputs_enabled(enabled: bool) -> void:
	guest_button.disabled = not enabled
	login_button.disabled = not enabled
	register_button.disabled = not enabled
	google_button.disabled = not enabled
	apple_button.disabled = not enabled
	facebook_button.disabled = not enabled
	email_input.editable = enabled
	password_input.editable = enabled
	reg_email_input.editable = enabled
	reg_username_input.editable = enabled
	reg_password_input.editable = enabled
	reg_confirm_password_input.editable = enabled

func _is_valid_email(email: String) -> bool:
	# Simple email validation
	var regex := RegEx.new()
	regex.compile("^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,}$")
	return regex.search(email) != null

func _go_to_lobby() -> void:
	# Navigate to lobby scene - use deferred call to avoid issues during signal callbacks
	if get_tree():
		get_tree().change_scene_to_file("res://scenes/lobby.tscn")
	else:
		# Fallback: try deferred call
		call_deferred("_deferred_go_to_lobby")

func _deferred_go_to_lobby() -> void:
	if get_tree():
		get_tree().change_scene_to_file("res://scenes/lobby.tscn")