class_name EditorViewport
extends Control
## Custom 2D viewport for the in-game editor (docs/architecture/editor.md
## §7.2 `EditorViewport`).
##
## Deliberately 2D top-down, not a 3D gizmo viewport -- per §8's own risk
## mitigation ("start with a 2D tile editor... matches CHUNK_SIZE_Z=1
## default; add 3D later"). Renders one tile layer as a grid plus the
## chunk's objects as dots, and turns clicks into calls on `EditorCore`
## routed through whichever tool is active in `ToolRegistry` -- this is UI
## glue, it never mutates `ChunkEditorModel` itself.
##
## Coordinate convention matches the rest of this codebase's tile system
## (scripts/tile_layer_node.gd `_tile_to_world`): chunk-local X/Y are the
## flat ground plane, Z is height (CHUNK_SIZE_Z=1 by default -- see
## scripts/chunk.gd). One grid cell == one world unit == `cell_size` pixels.

signal edit_applied

var core: EditorCore = null
var layer_idx: int = 0
var cell_size: float = 24.0
## Catalog id the next "object_place" click will place. Set by
## `InGameEditor` from `PalettePanel.object_selected`.
var pending_catalog_id: String = ""
## Tile id the next "brush" click paints. Cycled with number keys 0-9.
var current_tile_id: int = 1
## Elevation offset for placement and hotkey nudging (Q / E).
var current_elevation_offset: float = 0.0
## Whether to align placed object to surface normal slope.
var align_surface_normal: bool = false

var _hover_tx: int = -1
var _hover_ty: int = -1
var _mouse_down: bool = false
var _last_drag_tx: int = -1
var _last_drag_ty: int = -1

const TILE_EMPTY_COLOR := Color(0.15, 0.15, 0.17)
const TILE_SOLID_COLOR := Color(0.35, 0.55, 0.35)
const GRID_COLOR := Color(0, 0, 0, 0.25)
const OBJECT_COLOR := Color(0.9, 0.6, 0.2)
const OBJECT_SELECTED_COLOR := Color(1.0, 0.95, 0.2)


func _init() -> void:
	name = "EditorViewport"
	mouse_filter = Control.MOUSE_FILTER_STOP
	focus_mode = Control.FOCUS_ALL


func _notification(what: int) -> void:
	if what == NOTIFICATION_MOUSE_EXIT:
		_hover_tx = -1
		_hover_ty = -1
		_mouse_down = false
		_last_drag_tx = -1
		_last_drag_ty = -1
		queue_redraw()


func setup(p_core: EditorCore, p_layer_idx: int = 0) -> void:
	core = p_core
	layer_idx = p_layer_idx
	core.selection.selection_changed.connect(func(_id): queue_redraw())
	_resize_to_layer()
	queue_redraw()


func _resize_to_layer() -> void:
	var layer := core.model.get_layer(layer_idx)
	if layer == null:
		custom_minimum_size = Vector2(cell_size * 8, cell_size * 8)
		return
	custom_minimum_size = Vector2(layer.width * cell_size, layer.height * cell_size)


func _draw() -> void:
	if core == null:
		return
	var layer := core.model.get_layer(layer_idx)
	if layer == null:
		return

	for y in range(layer.height):
		for x in range(layer.width):
			var tile_id := layer.get_tile(x, y, 0)
			var color := TILE_EMPTY_COLOR
			var tdef := layer.get_tile_def(tile_id)
			if tdef != null and tdef.solid:
				color = TILE_SOLID_COLOR
			draw_rect(Rect2(x * cell_size, y * cell_size, cell_size, cell_size), color, true)

	for x in range(layer.width + 1):
		draw_line(Vector2(x * cell_size, 0), Vector2(x * cell_size, layer.height * cell_size), GRID_COLOR)
	for y in range(layer.height + 1):
		draw_line(Vector2(0, y * cell_size), Vector2(layer.width * cell_size, y * cell_size), GRID_COLOR)

	# Hover highlight over current cell
	if _hover_tx >= 0 and _hover_tx < layer.width and _hover_ty >= 0 and _hover_ty < layer.height:
		var h_rect := Rect2(_hover_tx * cell_size, _hover_ty * cell_size, cell_size, cell_size)
		draw_rect(h_rect, Color(1.0, 1.0, 1.0, 0.2), true)
		draw_rect(h_rect, Color(1.0, 0.95, 0.3, 0.85), false, 2.0)
		if core.tools.get_active_tool_id() == "object_place" and pending_catalog_id != "":
			var ghost_pos := Vector2((_hover_tx + 0.5) * cell_size, (_hover_ty + 0.5) * cell_size)
			draw_circle(ghost_pos, cell_size * 0.35, Color(1.0, 0.8, 0.2, 0.5))

	var default_font := ThemeDB.fallback_font
	for obj in core.model.payload.objects:
		var center := Vector2(obj.position.x * cell_size, obj.position.y * cell_size)
		var is_selected: bool = core.selection.get_selected() == obj.id
		var color := OBJECT_SELECTED_COLOR if is_selected else OBJECT_COLOR
		var r := cell_size * 0.38
		draw_circle(center, r, color)
		draw_arc(center, r, 0.0, TAU, 16, Color(0, 0, 0, 0.85), 1.5)
		if is_selected:
			draw_arc(center, r + 3.0, 0.0, TAU, 16, Color(1, 1, 1, 0.95), 2.0)

		var display_name: String = ""
		if obj.properties is Dictionary and obj.properties.has("display_name"):
			display_name = str(obj.properties["display_name"])
		if display_name == "":
			display_name = obj.id
		draw_string(default_font, center + Vector2(-r * 1.5, -r - 2), display_name.left(6), HORIZONTAL_ALIGNMENT_CENTER, int(r * 3.0), 10, Color(1, 1, 1, 0.9))

	# Draw motion waypoint path & gizmos for selected object
	var sel_id := core.selection.get_selected()
	if sel_id != "":
		var sel_obj := core.model.find_object(sel_id)
		if sel_obj != null and sel_obj.properties is Dictionary and sel_obj.properties.has("motion"):
			var m_cfg = sel_obj.properties["motion"]
			if m_cfg is Dictionary and m_cfg.has("waypoints") and m_cfg["waypoints"] is Array:
				var wps: Array = m_cfg["waypoints"]
				if not wps.is_empty():
					var prev_pt := Vector2(sel_obj.position.x * cell_size, sel_obj.position.y * cell_size)
					for i in range(wps.size()):
						var wp_val = wps[i]
						var wp_pos := Vector2.ZERO
						if wp_val is Array and wp_val.size() >= 2:
							wp_pos = Vector2(float(wp_val[0]) * cell_size, float(wp_val[1]) * cell_size)
						elif wp_val is Vector3:
							wp_pos = Vector2(wp_val.x * cell_size, wp_val.y * cell_size)

						draw_line(prev_pt, wp_pos, Color(0.2, 0.85, 1.0, 0.8), 2.0)
						var wr := cell_size * 0.28
						draw_circle(wp_pos, wr, Color(0.1, 0.6, 0.9, 0.85))
						draw_arc(wp_pos, wr, 0.0, TAU, 16, Color(1, 1, 1, 0.9), 1.5)
						draw_string(default_font, wp_pos + Vector2(-4, 4), str(i + 1), HORIZONTAL_ALIGNMENT_CENTER, 8, 10, Color(1, 1, 1))
						prev_pt = wp_pos



func _gui_input(event: InputEvent) -> void:
	if core == null:
		return
	if event is InputEventMouseButton:
		var mb := event as InputEventMouseButton
		if mb.button_index == MOUSE_BUTTON_LEFT:
			_mouse_down = mb.pressed
			if mb.pressed:
				_handle_click(mb.position)
				accept_event()
			else:
				_last_drag_tx = -1
				_last_drag_ty = -1
	elif event is InputEventMouseMotion:
		var mm := event as InputEventMouseMotion
		var tx := int(floor(mm.position.x / cell_size))
		var ty := int(floor(mm.position.y / cell_size))
		if tx != _hover_tx or ty != _hover_ty:
			_hover_tx = tx
			_hover_ty = ty
			queue_redraw()
		if _mouse_down and (tx != _last_drag_tx or ty != _last_drag_ty):
			var active_tool := core.tools.get_active_tool_id()
			if active_tool in ["brush", "erase"]:
				_handle_click(mm.position)
		accept_event()
	elif event is InputEventKey:
		var key := event as InputEventKey
		if key.pressed and not key.echo:
			_handle_key(key)


func _handle_key(key: InputEventKey) -> void:
	if key.keycode >= KEY_0 and key.keycode <= KEY_9:
		current_tile_id = key.keycode - KEY_0
	elif key.keycode == KEY_E:
		current_elevation_offset += 0.5
		var sel := core.selection.get_selected()
		if sel != "":
			core.adjust_object_elevation(sel, 0.5)
			edit_applied.emit()
			queue_redraw()
	elif key.keycode == KEY_Q:
		current_elevation_offset = maxf(0.0, current_elevation_offset - 0.5)
		var sel := core.selection.get_selected()
		if sel != "":
			core.adjust_object_elevation(sel, -0.5)
			edit_applied.emit()
			queue_redraw()
	elif key.keycode == KEY_END:
		var sel := core.selection.get_selected()
		if sel != "":
			if core.drop_object_to_surface(sel):
				edit_applied.emit()
				queue_redraw()
	elif key.keycode == KEY_R:
		align_surface_normal = not align_surface_normal
	elif key.keycode == KEY_W:
		var sel := core.selection.get_selected()
		if sel != "" and _hover_tx >= 0 and _hover_ty >= 0:
			var obj := core.model.find_object(sel)
			if obj != null:
				var motion_dict = obj.properties.get("motion", {"motion_type": "waypoint", "waypoints": []})
				if not (motion_dict is Dictionary):
					motion_dict = {"motion_type": "waypoint", "waypoints": []}
				var wps = motion_dict.get("waypoints", [])
				wps.append([float(_hover_tx), float(_hover_ty), obj.position.z])
				motion_dict["motion_type"] = "waypoint"
				motion_dict["waypoints"] = wps
				core.set_object_property(sel, "motion", motion_dict)
				edit_applied.emit()
				queue_redraw()
	elif key.keycode == KEY_BACKSPACE:
		var sel := core.selection.get_selected()
		if sel != "":
			var obj := core.model.find_object(sel)
			if obj != null and obj.properties is Dictionary and obj.properties.has("motion"):
				var motion_dict = obj.properties["motion"]
				if motion_dict is Dictionary and motion_dict.has("waypoints") and motion_dict["waypoints"] is Array:
					var wps: Array = motion_dict["waypoints"]
					if not wps.is_empty():
						wps.pop_back()
						motion_dict["waypoints"] = wps
						core.set_object_property(sel, "motion", motion_dict)
						edit_applied.emit()
						queue_redraw()


func _handle_click(local_pos: Vector2) -> void:
	var tx := int(floor(local_pos.x / cell_size))
	var ty := int(floor(local_pos.y / cell_size))
	_last_drag_tx = tx
	_last_drag_ty = ty

	match core.tools.get_active_tool_id():
		"brush":
			if core.paint_tile(layer_idx, tx, ty, current_tile_id):
				edit_applied.emit()
				queue_redraw()
		"erase":
			var hit := _object_at(tx, ty)
			var changed: bool = core.delete_object(hit) if hit != "" else core.erase_tile(layer_idx, tx, ty)
			if changed:
				edit_applied.emit()
				queue_redraw()
		"object_place":
			if pending_catalog_id != "":
				var existing_hit := _highest_object_at(tx, ty)
				var new_id: String = ""
				if existing_hit != "":
					new_id = core.place_object_stacked(
						pending_catalog_id,
						existing_hit,
						Vector3(tx + 0.5, ty + 0.5, 0.0),
						Vector3(0, 0, 1),
						current_elevation_offset,
						align_surface_normal
					)
				else:
					new_id = core.place_object(
						pending_catalog_id,
						Vector3(tx + 0.5, ty + 0.5, current_elevation_offset)
					)
				if new_id != "":
					edit_applied.emit()
					queue_redraw()
		"select":
			core.select_object(_object_at(tx, ty))
			edit_applied.emit()
			queue_redraw()


func _object_at(tx: int, ty: int) -> String:
	for obj in core.model.payload.objects:
		if int(floor(obj.position.x)) == tx and int(floor(obj.position.y)) == ty:
			return obj.id
	return ""


func _highest_object_at(tx: int, ty: int) -> String:
	var best_id := ""
	var max_z: float = -1.0
	for obj in core.model.payload.objects:
		if int(floor(obj.position.x)) == tx and int(floor(obj.position.y)) == ty:
			if obj.position.z > max_z:
				max_z = obj.position.z
				best_id = obj.id
	return best_id


func _can_drop_data(_at_position: Vector2, data: Variant) -> bool:
	if data is Dictionary and data.get("type") == "model_placement":
		return true
	return false


func _drop_data(at_position: Vector2, data: Variant) -> void:
	if not _can_drop_data(at_position, data):
		return
	if core == null:
		return
	var dict: Dictionary = data as Dictionary
	var cat_id: String = dict.get("catalog_id", "")
	if cat_id == "":
		cat_id = dict.get("model_name", "object").to_lower().replace(" ", "_")

	var tx := int(floor(at_position.x / cell_size))
	var ty := int(floor(at_position.y / cell_size))
	var existing_hit := _highest_object_at(tx, ty)
	var new_id := ""
	if existing_hit != "":
		new_id = core.place_object_stacked(
			cat_id,
			existing_hit,
			Vector3(tx + 0.5, ty + 0.5, 0.0),
			Vector3(0, 0, 1),
			current_elevation_offset,
			align_surface_normal
		)
	else:
		new_id = core.place_object(
			cat_id,
			Vector3(tx + 0.5, ty + 0.5, current_elevation_offset)
		)
	if new_id != "":
		edit_applied.emit()
		queue_redraw()