extends Control

@export var min_zoom: float = 0.3
@export var max_zoom: float = 3.0

@onready var content: Node2D = $MapContent
@onready var open_button: IconButton = get_node("../MapButton")
@onready var recenter_button: IconButton = $RecenterButton
@onready var close_button: IconButton = $CloseButton
@onready var fleet: Node2D = get_node("../../Fleet")

var touches: Dictionary = {}
var pinch_active: bool = false
var pinch_start_distance: float = 0.0
var pinch_start_zoom: float = 1.0


func _ready() -> void:
	open_button.pressed.connect(open_map)
	recenter_button.pressed.connect(recenter_view)
	close_button.pressed.connect(close_map)
	# #128: a dialog stops the tree, and the prologue opens on one - so
	# _process's first frame never comes and the button below would sit on
	# screen behind the opening line. Applied once here too, where it does
	# not depend on the game running.
	_apply_intro_lock()


func _process(_delta: float) -> void:
	_apply_intro_lock()


# #122: the prologue leaves movement and nothing else, and the map is a
# button like any other. Owned here rather than by BuildController, which
# hides the rest - this button belongs to the map.
func _apply_intro_lock() -> void:
	if GameState.intro_active:
		if open_button.visible:
			open_button.visible = false
		if visible:
			close_map()
			open_button.visible = false
	elif not open_button.visible and not visible:
		open_button.visible = true


func open_map() -> void:
	visible = true
	open_button.visible = false
	recenter_view()


func close_map() -> void:
	visible = false
	open_button.visible = true
	touches.clear()
	pinch_active = false


func recenter_view() -> void:
	var fleet_local: Vector2 = fleet.get_centroid() * content.WORLD_TO_LOCAL
	var viewport_center: Vector2 = get_viewport_rect().size / 2.0
	content.position = viewport_center - fleet_local * content.scale.x


# The map takes over touch input while it is open, so a drag pans the map
# instead of ordering the fleet somewhere. What it must NOT take over is a
# touch aimed at its own buttons.
#
# _input() runs BEFORE the GUI system, so set_input_as_handled() here stopped
# the touch ever reaching CloseButton._gui_input: the map could be opened and
# then not closed. On Android and desktop that stayed hidden, because Godot
# also emits an emulated MOUSE event for each touch and this only ever
# swallowed touch events - the button still got the mouse one, a second
# chance a phone browser does not give. So it surfaced on the web build,
# while being a real routing bug on every platform.
#
# Letting those events through is safe: IconButton consumes them with
# accept_event(), which marks them handled before GameController's
# _unhandled_input runs - so tapping Close still cannot also move the fleet.
func _input(event: InputEvent) -> void:
	if not visible:
		return

	if event is InputEventScreenTouch:
		# A press over one of the map's own buttons is never adopted, and
		# because it is never adopted, neither is anything else that touch
		# goes on to do - the index simply never enters `touches`.
		if event.pressed and _over_own_button(event.position):
			return
		if not event.pressed and not touches.has(event.index):
			return
		_handle_touch(event)
		get_viewport().set_input_as_handled()
	elif event is InputEventScreenDrag:
		if not touches.has(event.index):
			return
		_handle_drag(event)
		get_viewport().set_input_as_handled()
	elif event is InputEventMagnifyGesture:
		_handle_magnify(event)
		get_viewport().set_input_as_handled()


# Asked of the children rather than listed by name, so a button added to the
# map panel later is covered without anyone having to remember this exists.
# Keyed on having a `pressed` signal: the backdrop is a full-screen ColorRect
# and would otherwise match every point on the display.
func _over_own_button(at: Vector2) -> bool:
	for child in get_children():
		if child is Control and child.visible and child.has_signal("pressed") \
				and (child as Control).get_global_rect().has_point(at):
			return true
	return false


func _handle_touch(event: InputEventScreenTouch) -> void:
	if event.pressed:
		touches[event.index] = event.position
		if touches.size() == 2:
			pinch_active = true
			var positions: Array = touches.values()
			pinch_start_distance = positions[0].distance_to(positions[1])
			pinch_start_zoom = content.scale.x
	else:
		touches.erase(event.index)
		if touches.size() < 2:
			pinch_active = false


func _handle_drag(event: InputEventScreenDrag) -> void:
	if not touches.has(event.index):
		return
	var previous_pos: Vector2 = touches[event.index]
	touches[event.index] = event.position

	if pinch_active and touches.size() == 2 and pinch_start_distance > 0.0:
		var positions: Array = touches.values()
		var current_distance: float = positions[0].distance_to(positions[1])
		var new_zoom: float = pinch_start_zoom * (current_distance / max(pinch_start_distance, 1.0))
		_set_zoom(new_zoom)
	elif touches.size() == 1:
		content.position += event.position - previous_pos


func _handle_magnify(event: InputEventMagnifyGesture) -> void:
	_set_zoom(content.scale.x * event.factor)


func _set_zoom(z: float) -> void:
	var clamped: float = clamp(z, min_zoom, max_zoom)
	content.scale = Vector2(clamped, clamped)