# (c) 2023-present Eroax
# (c) 2023-present Yagich
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
extends GraphEdit
class_name DeckRendererGraphEdit

## Reference to the [DeckNodeRendererGraphNode] used for later instantiation
@export var NODE_SCENE: PackedScene
## Reference to the [AddNodeMenu] used for later instantiation
@export var ADD_NODE_MENU_SCENE: PackedScene

## The [PopupPanel] that holds the [AddNodeMenu] scene.
var search_popup_panel: PopupPanel
## Stores instance of [AddNodeMenu] that is used under [member search_popup_panel]
var add_node_menu: AddNodeMenu

## Used to specify the size of [member search_popup_panel].
@export var search_popup_size: Vector2i = Vector2i(500, 300)
## Stores the position of the [member search_popup_panel] for use when adding
## nodes in [method _on_add_node_menu_node_selected]
var popup_position: Vector2

var rename_popup := RenamePopup.new()
@export var rename_popup_size: Vector2i = Vector2i(200, 0)

## References the [Deck] that holds all the functional properties of this [DeckRendererGraphEdit]
var deck: Deck:
	set(v):
		deck = v
		deck.node_added.connect(_on_deck_node_added)
		deck.node_removed.connect(_on_deck_node_removed)
		deck.nodes_disconnected.connect(_on_deck_nodes_disconnected)

## Emits when Group creation is requested.  Ex. Hitting the "group_nodes" Hotkey.
signal group_enter_requested(group_id: String)

var dirty: bool = false:
	set(v):
		if change_dirty:
			dirty = v
			dirty_state_changed.emit()
var is_group: bool = false

var change_dirty: bool = true

signal dirty_state_changed

## Sets up the [member search_popup_panel] with an instance of [member ADD_NODE_SCENE]
## stored in [member add_node_menu].  And sets its size of [member search_popup_panel] to
## [member add_node_popup_size]
func _ready() -> void:
	add_node_menu = ADD_NODE_MENU_SCENE.instantiate()
	search_popup_panel = PopupPanel.new()
	search_popup_panel.add_child(add_node_menu)
	search_popup_panel.size = search_popup_size
	add_child(search_popup_panel, false, Node.INTERNAL_MODE_BACK)

	rename_popup = RenamePopup.new()
	rename_popup.rename_confirmed.connect(_on_rename_popup_rename_confirmed)
	rename_popup.close_requested.connect(_on_rename_popup_closed)
	add_child(rename_popup, false, Node.INTERNAL_MODE_FRONT)

	for t: DeckType.Types in DeckType.CONVERSION_MAP:
		for out_type: DeckType.Types in DeckType.CONVERSION_MAP[t]:
			add_valid_connection_type(t, out_type)

	add_node_menu.node_selected.connect(_on_add_node_menu_node_selected)

	connection_request.connect(attempt_connection)
	disconnection_request.connect(attempt_disconnect)

## Receives [signal GraphEdit.connection_request] and attempts to create a
## connection between the two [DeckNode]s involved, utilizes [NodeDB] for accessing them.
func attempt_connection(from_node_name: StringName, from_port: int, to_node_name: StringName, to_port: int) -> void:
	var from_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(from_node_name))
	var to_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(to_node_name))

	#var from_output := from_node_renderer.node.get_global_port_idx_from_output(from_port)
	#var to_input := to_node_renderer.node.get_global_port_idx_from_input(to_port)

	if deck.connect_nodes(from_node_renderer.node._id, to_node_renderer.node._id, from_port, to_port):
		connect_node(
				from_node_renderer.name,
				from_port,
				to_node_renderer.name,
				to_port
			)
		dirty = true


func _is_node_hover_valid(from_node: StringName, from_port: int, to_node: StringName, to_port: int) -> bool:
	var from_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(from_node))
	var to_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(to_node))
	
	return deck.is_valid_connection(from_node_renderer.node._id, to_node_renderer.node._id, from_port, to_port)

## Receives [signal GraphEdit.disconnection_request] and attempts to disconnect the two [DeckNode]s
## involved, utilizes [NodeDB] for accessing them.
func attempt_disconnect(from_node_name: StringName, from_port: int, to_node_name: StringName, to_port: int) -> void:
	var from_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(from_node_name))
	var to_node_renderer: DeckNodeRendererGraphNode = get_node(NodePath(to_node_name))

	#var from_output := from_node_renderer.node.get_global_port_idx_from_output(from_port)
	#var to_input := to_node_renderer.node.get_global_port_idx_from_input(to_port)

	deck.disconnect_nodes(from_node_renderer.node._id, to_node_renderer.node._id, from_port, to_port)

	disconnect_node(
				from_node_renderer.name,
				from_port,
				to_node_renderer.name,
				to_port
			)
	dirty = true

## Returns the associated [DeckNodeRendererGraphNode] for the supplied [DeckNode].
## Or [code]null[/code] if none is found.
func get_node_renderer(node: DeckNode) -> DeckNodeRendererGraphNode:
	for i: DeckNodeRendererGraphNode in get_children():
		if i.node == node:
			return i

	return null

## Updates [member Deck]s meta property "offset" whenever [member GraphEdit.scroll_offset]
func _on_scroll_offset_changed(offset: Vector2) -> void:
	deck.set_meta("offset", offset)


## Setups all the data from the set [member deck] in this [DeckRendererGraphEdit]
func initialize_from_deck() -> void:
	change_dirty = false
	for i in get_children():
		i.queue_free()

	is_group = deck.is_group
	for node_id in deck.nodes:
		var node_renderer: DeckNodeRendererGraphNode = NODE_SCENE.instantiate()
		node_renderer.node = deck.nodes[node_id]
		add_child(node_renderer)
		node_renderer.position_offset = node_renderer.node.position_as_vector2()
	change_dirty = true
	dirty = false

	refresh_connections()
	
	var ofs = deck.get_meta("offset", Vector2())
	set_scroll_offset.call_deferred(ofs)


## Loops through all [DeckNode]s in [member Deck.nodes] and calls
## [method GraphEdit.connect_node] for all the connections that exist in each
func refresh_connections() -> void:
	for node_id in deck.nodes:
		var node: DeckNode = deck.nodes[node_id]
		var from_node: DeckNodeRendererGraphNode = get_children().filter(
			func(c: DeckNodeRendererGraphNode):
				return c.node._id == node_id
		)[0]

		for from_port in node.outgoing_connections:
			for to_node_id: String in node.outgoing_connections[from_port]:
				var to_node_ports = node.outgoing_connections[from_port][to_node_id]
				var renderer: Array = get_children().filter(
					func(c: DeckNodeRendererGraphNode):
						return c.node._id == to_node_id
				)
				if renderer.is_empty():
					break
				var to_node: DeckNodeRendererGraphNode = renderer[0]
				for to_node_port: int in to_node_ports:
					connect_node(
						from_node.name,
						from_port,
						to_node.name,
						to_node_port
					)

## Connected to [signal Deck.node_added], used to instance the required
## [DeckNodeRendererGraphNode] and set it's [member DeckNodeRenderGraphNode.position_offset]
func _on_deck_node_added(node: DeckNode) -> void:
	var inst: DeckNodeRendererGraphNode = NODE_SCENE.instantiate()
	inst.node = node
	add_child(inst)
	inst.position_offset = inst.node.position_as_vector2()
	dirty = true


## Connected to [signal Deck.node_added], used to remove the specified
## [DeckNodeRendererGraphNode] and queue_free it.
func _on_deck_node_removed(node: DeckNode) -> void:
	for renderer: DeckNodeRendererGraphNode in get_children():
		if renderer.node != node:
			continue
		# TODO: when multiple nodes are removed and they are connected, the renderer will break
		# trying to get an invalid node. (GraphEdit, this is not on us.)
		# consider a batch removed signal for Deck or a separate signal for grouping nodes in 0.0.6.
		renderer.queue_free()
		break
	dirty = true

## Utility function that gets all [DeckNodeRenderGraphNode]s that are selected
## See [member GraphNode.selected]
func get_selected_nodes() -> Array:
	return get_children().filter(
		func(x: DeckNodeRendererGraphNode):
			return x.selected
	)

## Executes functionality based off hotkey inputs.  Specifically handles creating groups
## based off the action "group_nodes".
func _gui_input(event: InputEvent) -> void:
	if event.is_action_pressed("group_nodes") and get_selected_nodes().size() > 0:
		clear_connections()
		var nodes = get_selected_nodes().map(
			func(x: DeckNodeRendererGraphNode):
				return x.node
		)
		deck.group_nodes(nodes)
		refresh_connections()
		get_viewport().set_input_as_handled()
	
	if event.is_action_pressed("debug_make_unique") and get_selected_nodes().size() == 1:
		var node: DeckNode = get_selected_nodes().map(
			func(x: DeckNodeRendererGraphNode):
				return x.node
		)[0]
		if node.node_type != "group_node":
			return
		
		node.make_unique()

	if event.is_action_pressed("rename_node") and get_selected_nodes().size() == 1:
		var node: DeckNodeRendererGraphNode = get_selected_nodes()[0]
		var pos := get_viewport_rect().position + get_global_mouse_position()
		rename_popup.popup_on_parent(Rect2i(pos, rename_popup_size))
		rename_popup.le.size.x = rename_popup_size.x
		rename_popup.set_text(node.title)


## Handles entering groups with action "enter_group".  Done here to bypass neighbor
## functionality.
func _input(event: InputEvent) -> void:
	if not has_focus():
		return

	if event.is_action_pressed("enter_group") and get_selected_nodes().size() == 1:
		if (get_selected_nodes()[0] as DeckNodeRendererGraphNode).node.node_type != "group_node":
			return
		group_enter_requested.emit((get_selected_nodes()[0] as DeckNodeRendererGraphNode).node.group_id)
		get_viewport().set_input_as_handled()


func _on_rename_popup_rename_confirmed(new_name: String) -> void:
	var node: DeckNodeRendererGraphNode = get_selected_nodes()[0]
	node.title = new_name
	node.node.rename(new_name)
	dirty = true


func _on_rename_popup_closed() -> void:
	pass


## Opens [member search_popup_panel] at the mouse position.  Connected to [signal GraphEdit.popup_request]
func _on_popup_request(p_popup_position: Vector2) -> void:
	var p := get_viewport_rect().position + get_global_mouse_position()
	p += Vector2(10, 10)
	var r := Rect2i(p, search_popup_panel.size)
	search_popup_panel.popup_on_parent(r)
	add_node_menu.focus_search_bar()
	popup_position = p_popup_position

## Connected to [signal AddNodeMenu.node_selected] and creates a [DeckNode] using
## [method NodeDB.instance_node].  Then placing it at the [member scroll_offset] +
## [member popup_position] / [member zoom]
func _on_add_node_menu_node_selected(type: String) -> void:
	var node := NodeDB.instance_node(type) as DeckNode
	deck.add_node_inst(node)
	var node_pos := ((scroll_offset + popup_position) / zoom)
	if snapping_enabled:
		node_pos = node_pos.snapped(Vector2(snapping_distance, snapping_distance))

	get_node_renderer(node).position_offset = node_pos

	search_popup_panel.hide()


func _on_deck_nodes_disconnected(from_node_id: String, to_node_id: String, from_output_port: int, to_input_port: int) -> void:
	print("1")
	var from_node: DeckNodeRendererGraphNode = get_children().filter(
		func(x: DeckNodeRendererGraphNode):
			return x.node._id == from_node_id
	)[0]
	var to_node: DeckNodeRendererGraphNode = get_children().filter(
		func(x: DeckNodeRendererGraphNode):
			return x.node._id == to_node_id
	)[0]
	
	print(is_node_connected(from_node.name, from_output_port, to_node.name, to_input_port))
	disconnect_node(from_node.name, from_output_port, to_node.name, to_input_port)


func _on_delete_nodes_request(nodes: Array[StringName]) -> void:
	var node_ids := nodes.map(
		func(n: StringName):
			return (get_node(NodePath(n)) as DeckNodeRendererGraphNode).node._id
	)

	clear_connections()
	
	if node_ids.is_empty():
		return

	for node_id in node_ids:
		deck.remove_node(node_id, true)

	refresh_connections()
	dirty = true


func _on_copy_nodes_request() -> void:
	var selected := get_selected_nodes()
	if selected.is_empty():
		return

	var selected_ids: Array[String] = []
	selected_ids.assign(selected.map(
		func(x: DeckNodeRendererGraphNode):
			return x.node._id
			))

	DisplayServer.clipboard_set(deck.copy_nodes_json(selected_ids))


func _on_paste_nodes_request() -> void:
	var clip := DisplayServer.clipboard_get()
	var node_pos := (get_local_mouse_position() + scroll_offset - (Vector2(75.0, 0.0) * zoom)) / zoom

	if snapping_enabled:
		node_pos = node_pos.snapped(Vector2(snapping_distance, snapping_distance))

	clear_connections()

	deck.paste_nodes_from_json(clip, node_pos)

	refresh_connections()
	dirty = true


func _on_duplicate_nodes_request() -> void:
	var selected := get_selected_nodes()
	if selected.is_empty():
		return

	var selected_ids: Array[String] = []
	selected_ids.assign(selected.map(
		func(x: DeckNodeRendererGraphNode):
			return x.node._id
			))

	clear_connections()

	deck.duplicate_nodes(selected_ids)

	refresh_connections()
	dirty = true


class RenamePopup extends Popup:
	var le := LineEdit.new()

	signal rename_confirmed(new_text: String)

	func _ready() -> void:
		add_child(le)
		le.placeholder_text = "New Name"
		le.text_submitted.connect(
			func(new_text: String):
				if new_text.is_empty():
					return

				rename_confirmed.emit(new_text)
				hide()
		)


	func set_text(text: String) -> void:
		le.text = text
		le.select_all()
		le.grab_focus()