Add persistent light and dark themes

project.godot

@@ -18,6 +18,7 @@ config/icon="res://icon.svg"
 [autoload]
 
 AuthState="*res://scripts/autoload/auth_state.gd"
+UIThemeService="*res://scripts/autoload/ui_theme_service.gd"
 UISoundService="*res://scripts/autoload/ui_sound_service.gd"
 QuestionBankService="*res://scripts/autoload/question_bank_service.gd"
 ProgressionService="*res://scripts/autoload/progression_service.gd"

scripts/autoload/ui_theme_service.gd

@@ -0,0 +1,61 @@
+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)
+
+
+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()
+	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.")

scripts/autoload/ui_theme_service.gd.uid

@@ -0,0 +1 @@
+uid://dgfxwfgg7bapl

scripts/ui/main.gd

@@ -9,11 +9,15 @@ var user_label: Label
 var app_menu: PanelContainer
 var menu_exit_button: Button
 var sound_toggle: CheckButton
+var theme_button: Button
+var theme_service
 var current_screen_name := ""
 
 func _ready() -> void:
+	theme_service = get_node("/root/UIThemeService")
 	Style.apply_app_theme(self)
 	_build_ui()
+	theme_service.theme_changed.connect(_on_theme_changed)
 	resized.connect(_update_responsive_layout)
 	_update_responsive_layout()
 	show_screen("selection" if AuthState.is_logged_in else "login", "exam")
@@ -92,6 +96,14 @@ func _build_ui() -> void:
 	user_label.gui_input.connect(_on_user_label_gui_input)
 	header.add_child(user_label)
 
+	theme_button = Button.new()
+	theme_button.custom_minimum_size = Vector2(44, 44)
+	theme_button.add_theme_font_size_override("font_size", 22)
+	UISoundService.set_button_sound(theme_button, "toggle")
+	theme_button.pressed.connect(theme_service.toggle_theme)
+	header.add_child(theme_button)
+	_refresh_theme_button()
+
 	var screens_container := MarginContainer.new()
 	screens_container.name = "Screens"
 	screens_container.size_flags_vertical = Control.SIZE_EXPAND_FILL
@@ -176,6 +188,22 @@ func _refresh_header_stats() -> void:
 		user_label.text = AuthState.username if AuthState.is_logged_in else ""
 
 
+func _on_theme_changed(is_dark_mode: bool) -> void:
+	Style.refresh_tree(self, not is_dark_mode)
+	_refresh_theme_button()
+	var player = screens.get("player")
+	if player != null and player.has_method("refresh_theme_controls"):
+		player.refresh_theme_controls()
+
+
+func _refresh_theme_button() -> void:
+	if theme_button == null:
+		return
+	theme_button.text = "☀" if theme_service.is_dark_mode() else "☾"
+	theme_button.tooltip_text = "Switch to light mode" if theme_service.is_dark_mode() else "Switch to dark mode"
+	Style.style_chip(theme_button, Style.CYAN)
+
+
 func _logout() -> void:
 	_close_app_menu()
 	if BlockSessionService.block_started:

scripts/ui/question_player.gd

@@ -18,6 +18,7 @@ const REPORT_CATEGORIES := [
 ]
 
 var main: Control
+var theme_service
 var choice_buttons: Array[Button] = []
 var choice_percent_labels: Array[Label] = []
 var choice_top_labels: Array[Label] = []
@@ -55,6 +56,7 @@ var text_larger_button: Button
 var labs_button: Button
 var flag_button: Button
 var report_button: Button
+var theme_button: Button
 var question_toolbar: HBoxContainer
 var nav_palette: HBoxContainer
 var question_content: VBoxContainer
@@ -86,6 +88,7 @@ var shake_time := 0.0
 var shake_origin := Vector2.ZERO
 
 func _ready() -> void:
+	theme_service = get_node("/root/UIThemeService")
 	set_anchors_preset(Control.PRESET_FULL_RECT)
 	add_theme_constant_override("separation", 10)
 	if not QuestionBankService.choice_percentages_updated.is_connected(_on_choice_percentages_updated):
@@ -131,6 +134,14 @@ func _ready() -> void:
 	question_toolbar.add_theme_constant_override("separation", 8)
 	question_toolbar.alignment = BoxContainer.ALIGNMENT_END
 
+	theme_button = Button.new()
+	theme_button.custom_minimum_size = Vector2(44, 44)
+	theme_button.add_theme_font_size_override("font_size", 22)
+	UISoundService.set_button_sound(theme_button, "toggle")
+	theme_button.pressed.connect(theme_service.toggle_theme)
+	question_toolbar.add_child(theme_button)
+	_refresh_theme_button()
+
 	text_smaller_button = Button.new()
 	text_smaller_button.text = "A-"
 	text_smaller_button.tooltip_text = "Decrease text size"
@@ -622,12 +633,12 @@ func _submit_or_next() -> void:
 	if current_answer.is_empty():
 		if selected_choice == "":
 			return
+		var question_id_for_attempt := str(BlockSessionService.get_current_question().get("id", ""))
 		if BlockSessionService.session_kind == "core":
 			_collapse_resolved_followups()
 			var attempted_choice := selected_choice
-			var attempted_question_id := str(BlockSessionService.get_current_question().get("id", ""))
 			QuestionBankService.record_first_attempt(
-				attempted_question_id,
+				question_id_for_attempt,
 				attempted_choice,
 				_presented_choice_ids()
 			)
@@ -649,9 +660,8 @@ func _submit_or_next() -> void:
 			_trigger_wrong_feedback()
 			_apply_saved_choice_state()
 			return
-		var attempted_question_id := str(BlockSessionService.get_current_question().get("id", ""))
 		QuestionBankService.record_first_attempt(
-			attempted_question_id,
+			question_id_for_attempt,
 			selected_choice,
 			_presented_choice_ids()
 		)
@@ -742,7 +752,7 @@ func _trigger_wrong_feedback() -> void:
 	green_fog_time = 0.0
 	red_fog_time = FEEDBACK_FADE_SECONDS
 	if feedback_fog != null:
-		feedback_fog.color = Color(1.0, 0.0, 0.0, 0.26)
+		feedback_fog.color = Color(1.0, 0.0, 0.0, _feedback_overlay_alpha(false))
 
 
 func _trigger_correct_feedback() -> void:
@@ -757,7 +767,7 @@ func _trigger_correct_feedback() -> void:
 	for button in choice_buttons:
 		button.disabled = true
 	if feedback_fog != null:
-		feedback_fog.color = Color(0.25, 1.0, 0.25, 0.23)
+		feedback_fog.color = Color(0.25, 1.0, 0.25, _feedback_overlay_alpha(true))
 
 
 func _update_answer_feedback(delta: float) -> void:
@@ -770,11 +780,11 @@ func _update_answer_feedback(delta: float) -> void:
 
 	if red_fog_time > 0.0 and feedback_fog != null:
 		red_fog_time = max(0.0, red_fog_time - delta)
-		var red_alpha := 0.26 * (red_fog_time / FEEDBACK_FADE_SECONDS)
+		var red_alpha := _feedback_overlay_alpha(false) * (red_fog_time / FEEDBACK_FADE_SECONDS)
 		feedback_fog.color = Color(1.0, 0.0, 0.0, red_alpha)
 	elif green_fog_time > 0.0 and feedback_fog != null:
 		green_fog_time = max(0.0, green_fog_time - delta)
-		var green_alpha := 0.23 * (green_fog_time / FEEDBACK_FADE_SECONDS)
+		var green_alpha := _feedback_overlay_alpha(true) * (green_fog_time / FEEDBACK_FADE_SECONDS)
 		feedback_fog.color = Color(0.25, 1.0, 0.25, green_alpha)
 
 	if pending_correct_advance:
@@ -787,6 +797,12 @@ func _update_answer_feedback(delta: float) -> void:
 			_advance_or_finish()
 
 
+func _feedback_overlay_alpha(is_correct: bool) -> float:
+	if Style.is_dark:
+		return 0.23 if is_correct else 0.26
+	return 0.07
+
+
 func _reset_wrong_feedback() -> void:
 	if shake_time > 0.0:
 		position = shake_origin
@@ -853,6 +869,7 @@ func _toggle_report_current_question() -> void:
 
 
 func _refresh_toolbar_state() -> void:
+	_refresh_theme_button()
 	_refresh_labs_button()
 	if flag_button != null:
 		Style.style_chip(flag_button, Style.AMBER if flagged else Style.CYAN)
@@ -862,6 +879,30 @@ func _refresh_toolbar_state() -> void:
 		report_button.tooltip_text = "Report submitted; report another issue" if reported_question_ids.has(question_id) else "Report question"
 
 
+func refresh_theme_controls() -> void:
+	_refresh_theme_button()
+	if labs_button != null:
+		labs_button.icon = _make_labs_icon()
+	if flag_button != null:
+		flag_button.icon = _make_flag_icon()
+	if report_button != null:
+		report_button.icon = _make_report_icon()
+	if question_toolbar != null:
+		for child in question_toolbar.get_children():
+			if child is Button and child.tooltip_text == "Clear highlights":
+				child.icon = _make_clear_highlights_icon()
+	_refresh_toolbar_state()
+	_apply_saved_choice_state()
+
+
+func _refresh_theme_button() -> void:
+	if theme_button == null:
+		return
+	theme_button.text = "☀" if theme_service.is_dark_mode() else "☾"
+	theme_button.tooltip_text = "Switch to light mode" if theme_service.is_dark_mode() else "Switch to dark mode"
+	Style.style_chip(theme_button, Style.CYAN)
+
+
 func _refresh_player_stats() -> void:
 	if player_stats_label == null:
 		return
@@ -895,6 +936,7 @@ func _set_scaled_button_font(button: Button, base_size: int) -> void:
 
 func _set_scaled_rich_text(label: RichTextLabel, base_size: int) -> void:
 	label.set_meta("question_base_font_size", base_size)
+	label.add_theme_color_override("default_color", Style.TEXT)
 	label.add_theme_font_size_override("normal_font_size", _scaled_font_size(base_size))
 	label.add_theme_font_size_override("bold_font_size", _scaled_font_size(base_size))
 
@@ -1493,7 +1535,7 @@ func _apply_saved_choice_state() -> void:
 		choice_buttons[index].disabled = locked_wrong_choice_ids.has(id) and not has_followup_panel
 		_style_choice_button_for_state(index, id)
 		if locked_wrong_choice_ids.has(id):
-			choice_buttons[index].modulate = Color(1.0, 0.25, 0.25)
+			choice_buttons[index].modulate = Color(1.0, 0.25, 0.25) if Style.is_dark else Color.WHITE
 		elif eliminated.has(id):
 			choice_buttons[index].modulate = Color(0.45, 0.45, 0.45)
 		elif id == selected_choice:
@@ -1754,6 +1796,8 @@ func _style_followup_result_button(button: Button, is_correct: bool) -> void:
 	button.add_theme_stylebox_override("hover", Style.button_box(fill, border))
 	button.add_theme_stylebox_override("disabled", Style.button_box(fill, border))
 	button.add_theme_color_override("font_color", Style.TEXT)
+	button.add_theme_color_override("font_hover_color", Style.TEXT)
+	button.add_theme_color_override("font_disabled_color", Style.TEXT)
 
 
 func _unlock_after_followup() -> void:

scripts/ui/ui_style.gd

@@ -1,22 +1,77 @@
 extends RefCounted
 
-const BACKGROUND := Color("121827")
-const SURFACE := Color("1d2638")
-const SURFACE_DARK := Color("151c2b")
-const SURFACE_LIGHT := Color("27334a")
-const TEXT := Color("f6f8ff")
-const MUTED := Color("aeb8ca")
-const CYAN := Color("4de1ff")
-const LIME := Color("a6ff5f")
-const MAGENTA := Color("ff4fd8")
-const AMBER := Color("ffc857")
-const RED := Color("ff5f6d")
+static var BACKGROUND := Color("121827")
+static var SURFACE := Color("1d2638")
+static var SURFACE_DARK := Color("151c2b")
+static var SURFACE_LIGHT := Color("27334a")
+static var TEXT := Color("f6f8ff")
+static var MUTED := Color("aeb8ca")
+static var CYAN := Color("4de1ff")
+static var LIME := Color("a6ff5f")
+static var MAGENTA := Color("ff4fd8")
+static var AMBER := Color("ffc857")
+static var RED := Color("ff5f6d")
+static var BORDER := Color("33415c")
+static var is_dark := true
+
+const DARK_PALETTE := {
+	"background": Color("121827"), "surface": Color("1d2638"),
+	"surface_dark": Color("151c2b"), "surface_light": Color("27334a"),
+	"text": Color("f6f8ff"), "muted": Color("aeb8ca"),
+	"cyan": Color("4de1ff"), "lime": Color("a6ff5f"),
+	"magenta": Color("ff4fd8"), "amber": Color("ffc857"),
+	"red": Color("ff5f6d"), "border": Color("33415c")
+}
+const LIGHT_PALETTE := {
+	"background": Color("f4f7fb"), "surface": Color("ffffff"),
+	"surface_dark": Color("e8edf5"), "surface_light": Color("dce5f0"),
+	"text": Color("172033"), "muted": Color("59677c"),
+	"cyan": Color("007a99"), "lime": Color("347a18"),
+	"magenta": Color("a32187"), "amber": Color("986400"),
+	"red": Color("b42335"), "border": Color("aeb9c8")
+}
+const CUSTOM_DARK_TO_LIGHT := {
+	Color("111a2a"): Color("f8fafc"), Color("172337"): Color("fffffe"),
+	Color("182235"): Color("fefeff"), Color("26151a"): Color("fff1f2"),
+	Color("263752"): Color("aeb9c8"), Color("344463"): Color("aeb9c8"),
+	Color("405475"): Color("96a5b8"), Color("3b4964"): Color("aeb9c8"),
+	Color("303c55"): Color("b9c4d2"), Color("33425d"): Color("d2dce8"),
+	Color("26354f"): Color("e1e8f1"), Color("20384d"): Color("d8e8ed"),
+	Color("18465a"): Color("d4f2f7"), Color("20647e"): Color("b9e7ef"),
+	Color("153b4d"): Color("c6e8ed"), Color("21344a"): Color("d8e8ed"),
+	Color("202637"): Color("e5e9ef"), Color("2c3445"): Color("c8d0dc"),
+	Color("232b3d"): Color("e1e7ef"), Color("303b53"): Color("b7c2d0"),
+	Color("596982"): Color("66758a"), Color("1f7a3a"): Color("dff4e5"),
+	Color("8f1d2c"): Color("f8dce1")
+}
+
+
+static func set_dark_mode(value: bool) -> void:
+	is_dark = value
+	var palette: Dictionary = DARK_PALETTE if value else LIGHT_PALETTE
+	BACKGROUND = palette.background
+	SURFACE = palette.surface
+	SURFACE_DARK = palette.surface_dark
+	SURFACE_LIGHT = palette.surface_light
+	TEXT = palette.text
+	MUTED = palette.muted
+	CYAN = palette.cyan
+	LIME = palette.lime
+	MAGENTA = palette.magenta
+	AMBER = palette.amber
+	RED = palette.red
+	BORDER = palette.border
 
 static func apply_app_theme(root: Control) -> void:
 	var theme := Theme.new()
 	theme.set_color("font_color", "Label", TEXT)
 	theme.set_color("font_color", "Button", TEXT)
-	theme.set_color("font_color", "RichTextLabel", TEXT)
+	theme.set_color("font_hover_color", "Button", TEXT)
+	theme.set_color("font_pressed_color", "Button", TEXT)
+	theme.set_color("font_disabled_color", "Button", MUTED)
+	theme.set_color("default_color", "RichTextLabel", TEXT)
+	theme.set_color("font_selected_color", "RichTextLabel", TEXT)
+	theme.set_color("selection_color", "RichTextLabel", Color(CYAN, 0.28))
 	theme.set_font_size("font_size", "Label", 17)
 	theme.set_font_size("font_size", "Button", 16)
 	theme.set_stylebox("normal", "Button", button_box(SURFACE_LIGHT, Color("3b4964")))
@@ -27,10 +82,10 @@ static func apply_app_theme(root: Control) -> void:
 	root.theme = theme
 
 
-static func panel_box(color: Color = SURFACE, border: Color = Color("33415c")) -> StyleBoxFlat:
+static func panel_box(color: Color = SURFACE, border: Color = BORDER) -> StyleBoxFlat:
 	var box := StyleBoxFlat.new()
-	box.bg_color = color
-	box.border_color = border
+	box.bg_color = _color_for_current_theme(color)
+	box.border_color = _color_for_current_theme(border)
 	box.set_border_width_all(1)
 	box.corner_radius_top_left = 8
 	box.corner_radius_top_right = 8
@@ -45,8 +100,8 @@ static func panel_box(color: Color = SURFACE, border: Color = Color("33415c")) -
 
 static func button_box(color: Color, border: Color) -> StyleBoxFlat:
 	var box := StyleBoxFlat.new()
-	box.bg_color = color
-	box.border_color = border
+	box.bg_color = _color_for_current_theme(color)
+	box.border_color = _color_for_current_theme(border)
 	box.set_border_width_all(1)
 	box.corner_radius_top_left = 6
 	box.corner_radius_top_right = 6
@@ -76,9 +131,67 @@ static func style_answer_button(button: Button) -> void:
 	button.add_theme_stylebox_override("hover", button_box(Color("26354f"), CYAN))
 	button.add_theme_stylebox_override("pressed", button_box(Color("20384d"), CYAN))
 	button.add_theme_color_override("font_color", TEXT)
+	button.add_theme_color_override("font_disabled_color", MUTED)
 
 
 static func style_chip(button: Button, color: Color) -> void:
 	button.add_theme_stylebox_override("normal", button_box(Color(color, 0.22), color))
 	button.add_theme_stylebox_override("hover", button_box(Color(color, 0.34), color))
 	button.add_theme_color_override("font_color", TEXT)
+	button.add_theme_color_override("font_disabled_color", MUTED)
+
+
+static func refresh_tree(root: Control, was_dark: bool) -> void:
+	apply_app_theme(root)
+	_translate_control(root, DARK_PALETTE if was_dark else LIGHT_PALETTE, LIGHT_PALETTE if was_dark else DARK_PALETTE)
+
+
+static func _translate_control(control: Control, source: Dictionary, target: Dictionary) -> void:
+	if control is ColorRect:
+		control.color = _translate_color(control.color, source, target)
+	for color_name in ["font_color", "font_hover_color", "font_pressed_color", "font_disabled_color", "font_selected_color", "default_color", "font_uneditable_color"]:
+		if control.has_theme_color_override(color_name):
+			control.add_theme_color_override(color_name, _translate_color(control.get_theme_color(color_name), source, target))
+	for style_name in ["panel", "normal", "hover", "pressed", "disabled", "focus", "fill", "background", "read_only"]:
+		if control.has_theme_stylebox_override(style_name):
+			var box := control.get_theme_stylebox(style_name)
+			if box is StyleBoxFlat:
+				var translated := box.duplicate() as StyleBoxFlat
+				translated.bg_color = _translate_color(translated.bg_color, source, target)
+				translated.border_color = _translate_color(translated.border_color, source, target)
+				control.add_theme_stylebox_override(style_name, translated)
+	for child in control.get_children():
+		if child is Control:
+			_translate_control(child, source, target)
+
+
+static func _translate_color(color: Color, source: Dictionary, target: Dictionary) -> Color:
+	for key in source:
+		var candidate: Color = source[key]
+		if color.is_equal_approx(candidate):
+			var replacement: Color = target[key]
+			replacement.a = color.a
+			return replacement
+	for dark_color in CUSTOM_DARK_TO_LIGHT:
+		if color.is_equal_approx(dark_color):
+			var replacement: Color = CUSTOM_DARK_TO_LIGHT[dark_color]
+			replacement.a = color.a
+			return replacement
+	for dark_color in CUSTOM_DARK_TO_LIGHT:
+		var light_color: Color = CUSTOM_DARK_TO_LIGHT[dark_color]
+		if color.is_equal_approx(light_color):
+			var replacement: Color = dark_color
+			replacement.a = color.a
+			return replacement
+	return color
+
+
+static func _color_for_current_theme(color: Color) -> Color:
+	if is_dark:
+		return color
+	for dark_color in CUSTOM_DARK_TO_LIGHT:
+		if color.is_equal_approx(dark_color):
+			var replacement: Color = CUSTOM_DARK_TO_LIGHT[dark_color]
+			replacement.a = color.a
+			return replacement
+	return color

tests/ui_theme_test.gd

@@ -0,0 +1,40 @@
+extends SceneTree
+
+const Style := preload("res://scripts/ui/ui_style.gd")
+
+var failures := 0
+
+
+func _initialize() -> void:
+	Style.set_dark_mode(true)
+	var root := Control.new()
+	var background := ColorRect.new()
+	background.color = Style.BACKGROUND
+	root.add_child(background)
+	var panel := PanelContainer.new()
+	panel.add_theme_stylebox_override("panel", Style.panel_box(Color("172337"), Color("405475")))
+	root.add_child(panel)
+
+	Style.set_dark_mode(false)
+	Style.refresh_tree(root, true)
+	_assert(background.color.is_equal_approx(Style.BACKGROUND), "background should switch to light mode")
+	_assert(root.theme.get_color("default_color", "RichTextLabel").is_equal_approx(Style.TEXT), "rich text should use the light text color")
+	var light_box := panel.get_theme_stylebox("panel") as StyleBoxFlat
+	_assert(light_box.bg_color.is_equal_approx(Color("fffffe")), "custom panel surface should switch to light mode")
+
+	Style.set_dark_mode(true)
+	Style.refresh_tree(root, false)
+	_assert(background.color.is_equal_approx(Style.BACKGROUND), "background should switch back to dark mode")
+	_assert(root.theme.get_color("default_color", "RichTextLabel").is_equal_approx(Style.TEXT), "rich text should use the dark text color")
+	var dark_box := panel.get_theme_stylebox("panel") as StyleBoxFlat
+	_assert(dark_box.bg_color.is_equal_approx(Color("172337")), "custom panel surface should switch back to dark mode")
+
+	root.free()
+	quit(1 if failures > 0 else 0)
+
+
+func _assert(condition: bool, message: String) -> void:
+	if condition:
+		return
+	failures += 1
+	push_error(message)

tests/ui_theme_test.gd.uid

@@ -0,0 +1 @@
+uid://bm47u1leamc1h