extends Control

# Settings screen: player-facing video knobs on top of VideoSettings (the
# autoload holding + persisting them). Preset/AA/vsync/fps-cap/resolution
# scale apply immediately since they're Viewport- or DisplayServer-wide;
# glow/brightness/shadow/SDFGI/SSIL/SSAO apply the next time an arena loads
# an Environment, or instantly to an already-loaded one via
# VideoSettings.settings_changed (see arena.gd) — task 0.17.

const AA_OPTIONS := [
	{"name": "Off", "mode": VideoSettings.AAMode.OFF},
	{"name": "FXAA", "mode": VideoSettings.AAMode.FXAA},
	{"name": "MSAA 2x", "mode": VideoSettings.AAMode.MSAA_2X},
	{"name": "MSAA 4x", "mode": VideoSettings.AAMode.MSAA},
	{"name": "MSAA 4x + FXAA", "mode": VideoSettings.AAMode.MSAA_FXAA},
]

const PRESET_OPTIONS := [
	{"name": "Low", "preset": VideoSettings.Preset.LOW},
	{"name": "Medium", "preset": VideoSettings.Preset.MEDIUM},
	{"name": "High", "preset": VideoSettings.Preset.HIGH},
	{"name": "Custom", "preset": VideoSettings.Preset.CUSTOM},
]

const VSYNC_OPTIONS := [
	{"name": "Disabled", "mode": VideoSettings.VsyncMode.DISABLED},
	{"name": "Enabled", "mode": VideoSettings.VsyncMode.ENABLED},
	{"name": "Adaptive", "mode": VideoSettings.VsyncMode.ADAPTIVE},
]

@onready var preset_dropdown: OptionButton = %PresetDropdown
@onready var aa_dropdown: OptionButton = %AADropdown
@onready var glow_slider: HSlider = %GlowSlider
@onready var glow_value_label: Label = %GlowValueLabel
@onready var brightness_slider: HSlider = %BrightnessSlider
@onready var brightness_value_label: Label = %BrightnessValueLabel
@onready var resolution_slider: HSlider = %ResolutionSlider
@onready var resolution_value_label: Label = %ResolutionValueLabel
@onready var vsync_dropdown: OptionButton = %VsyncDropdown
@onready var fps_cap_dropdown: OptionButton = %FpsCapDropdown
@onready var fps_readout_label: Label = %FpsReadoutLabel

# fps_cap_dropdown item index -> VideoSettings divisor (0 = uncapped). Built
# in _ready() from the live refresh rate so the menu never hardcodes a
# specific display's numbers.
var _fps_cap_divisors: Array[int] = []
var _populating := false


func _ready() -> void:
	AudioManager.bind_tree_buttons(self)
	# An idle settings screen has no reason to render past the display's own
	# refresh rate; _on_back_pressed only returns to another capped menu, so
	# no uncap is needed there (contrast main_menu.gd's _leave_to_gameplay).
	var refresh_rate := DisplayServer.screen_get_refresh_rate()
	Engine.max_fps = int(refresh_rate) if refresh_rate > 0 else 0

	_populating = true
	_populate_preset_dropdown()
	_populate_aa_dropdown()
	_populate_vsync_dropdown()
	_populate_fps_cap_dropdown(refresh_rate)
	_populating = false

	glow_slider.value = VideoSettings.glow_scale
	brightness_slider.value = VideoSettings.brightness
	resolution_slider.value = VideoSettings.resolution_scale
	_update_glow_label()
	_update_brightness_label()
	_update_resolution_label()
	_update_fps_cap_enabled()


func _process(_delta: float) -> void:
	fps_readout_label.text = "%d fps" % Performance.get_monitor(Performance.TIME_FPS)


func _populate_preset_dropdown() -> void:
	preset_dropdown.clear()
	var selected := 0
	for i in PRESET_OPTIONS.size():
		preset_dropdown.add_item(PRESET_OPTIONS[i]["name"])
		if PRESET_OPTIONS[i]["preset"] == VideoSettings.preset:
			selected = i
	preset_dropdown.select(selected)


func _populate_aa_dropdown() -> void:
	aa_dropdown.clear()
	var selected := 0
	for i in AA_OPTIONS.size():
		aa_dropdown.add_item(AA_OPTIONS[i]["name"])
		if AA_OPTIONS[i]["mode"] == VideoSettings.aa_mode:
			selected = i
	aa_dropdown.select(selected)


func _populate_vsync_dropdown() -> void:
	vsync_dropdown.clear()
	var selected := 0
	for i in VSYNC_OPTIONS.size():
		vsync_dropdown.add_item(VSYNC_OPTIONS[i]["name"])
		if VSYNC_OPTIONS[i]["mode"] == VideoSettings.vsync_mode:
			selected = i
	vsync_dropdown.select(selected)


# Options derive from the live refresh rate rather than a fixed list, per
# task 0.17's "fps cap derived from screen_get_refresh_rate() divisors".
# A -1 (or otherwise non-positive) query falls back to "Uncapped" only,
# rather than presenting cap choices the engine can't compute a value for.
func _populate_fps_cap_dropdown(refresh_rate: float) -> void:
	fps_cap_dropdown.clear()
	_fps_cap_divisors.clear()
	fps_cap_dropdown.add_item("Uncapped")
	_fps_cap_divisors.append(0)
	if refresh_rate > 0.0:
		for divisor in [1, 2, 3, 4]:
			var hz := refresh_rate / float(divisor)
			fps_cap_dropdown.add_item("%d fps (refresh / %d)" % [roundi(hz), divisor])
			_fps_cap_divisors.append(divisor)
	var selected := _fps_cap_divisors.find(VideoSettings.fps_cap_divisor)
	fps_cap_dropdown.select(maxi(selected, 0))


# The fps cap dropdown only means anything with vsync Disabled — vsync
# itself already caps to (a multiple of) the refresh rate otherwise.
func _update_fps_cap_enabled() -> void:
	fps_cap_dropdown.disabled = VideoSettings.vsync_mode != VideoSettings.VsyncMode.DISABLED


func _update_glow_label() -> void:
	glow_value_label.text = "%d%%" % roundi(glow_slider.value * 100.0)


func _update_brightness_label() -> void:
	brightness_value_label.text = "%d%%" % roundi(brightness_slider.value * 100.0)


func _update_resolution_label() -> void:
	resolution_value_label.text = "%d%%" % roundi(resolution_slider.value * 100.0)


func _on_preset_dropdown_item_selected(index: int) -> void:
	VideoSettings.apply_preset(PRESET_OPTIONS[index]["preset"])
	# The bundle may have changed AA/resolution scale underneath the other
	# controls — resync them without re-triggering their own "user changed
	# this by hand" mark_custom() path.
	_populating = true
	_populate_aa_dropdown()
	resolution_slider.value = VideoSettings.resolution_scale
	_populating = false
	_update_resolution_label()


func _on_aa_dropdown_item_selected(index: int) -> void:
	VideoSettings.aa_mode = AA_OPTIONS[index]["mode"]
	VideoSettings.apply_aa()
	_mark_custom_if_user_driven()


func _on_glow_slider_value_changed(value: float) -> void:
	VideoSettings.glow_scale = value
	_update_glow_label()


func _on_brightness_slider_value_changed(value: float) -> void:
	VideoSettings.brightness = value
	_update_brightness_label()


func _on_resolution_slider_value_changed(value: float) -> void:
	VideoSettings.resolution_scale = value
	VideoSettings.apply_resolution_scale()
	_update_resolution_label()
	_mark_custom_if_user_driven()


func _on_vsync_dropdown_item_selected(index: int) -> void:
	VideoSettings.vsync_mode = VSYNC_OPTIONS[index]["mode"]
	VideoSettings.apply_vsync()
	_update_fps_cap_enabled()


func _on_fps_cap_dropdown_item_selected(index: int) -> void:
	VideoSettings.fps_cap_divisor = _fps_cap_divisors[index]
	VideoSettings.apply_fps_cap()


# Preset-gated fields (AA, resolution scale — glow/shadows/SDFGI/SSIL/SSAO
# have no direct control in this menu yet) flip the preset dropdown to
# Custom when the player overrides them by hand, so the dropdown never shows
# a preset name next to settings that preset doesn't actually produce. Not
# called while _populating (initial load) or while apply_preset() itself is
# writing these same fields (VideoSettings.mark_custom() no-ops there too,
# but skipping the redundant dropdown repopulation here is cheap).
func _mark_custom_if_user_driven() -> void:
	if _populating:
		return
	VideoSettings.mark_custom()
	_populating = true
	_populate_preset_dropdown()
	_populating = false


func _on_back_pressed() -> void:
	VideoSettings.save()
	get_tree().change_scene_to_file(ScenePaths.MAIN_MENU)


func _unhandled_input(event: InputEvent) -> void:
	if event.is_action_pressed("ui_cancel"):
		_on_back_pressed()