modbison/scripts/studio/studio_main.gd

class_name StudioMain
extends Control
## Standalone ModBison Studio Application Shell.
## Implements multi-panel docking layout, top menu bar with keyboard shortcuts,
## 3D interactive viewport with raycast picking, gizmos, hierarchy, inspector,
## collections dock, quick insert toolbar, instructions HUD, and simulation harness.

const MBWorldProjectIOClass = preload("res://scripts/studio/mbworld_project_io.gd")
const StudioViewportCameraClass = preload("res://scripts/studio/studio_viewport_camera.gd")
const TransformGizmo3DClass = preload("res://scripts/studio/gizmos/transform_gizmo_3d.gd")
const StudioHierarchyDockClass = preload("res://scripts/studio/studio_hierarchy_dock.gd")
const StudioInspectorDockClass = preload("res://scripts/studio/studio_inspector_dock.gd")
const StudioCollectionsDockClass = preload("res://scripts/studio/studio_collections_dock.gd")
const StudioSimulationManagerClass = preload("res://scripts/studio/studio_simulation_manager.gd")
const StudioHelpDialogClass = preload("res://scripts/studio/studio_help_dialog.gd")
const StaticObjectNodeClass = preload("res://scripts/static_object_node.gd")
const WorldObjectClass = preload("res://scripts/world_object.gd")

# Custom SubViewportContainer supporting drag & drop model placement and click picking
class StudioViewportContainer extends SubViewportContainer:
	var studio_main: Node = null

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

	func _drop_data(at_position: Vector2, data: Variant) -> void:
		if studio_main != null and studio_main.has_method("handle_viewport_drop"):
			studio_main.handle_viewport_drop(at_position, data)

	func _gui_input(event: InputEvent) -> void:
		if studio_main != null and studio_main.has_method("handle_viewport_input"):
			studio_main.handle_viewport_input(event)


# Core state
var core: EditorCore = null
var current_project_path: String = ""
var project_title: String = "Untitled World"

# Top Menu & Toolbar
var _menu_bar: MenuBar
var _toolbar: HBoxContainer
var _btn_select: Button
var _btn_move: Button
var _btn_rotate: Button
var _btn_scale: Button
var _btn_play: Button
var _btn_stop: Button
var _snap_spin: SpinBox

# Main Viewport & 3D Elements
var _vp_container: StudioViewportContainer
var _sub_viewport: SubViewport
var _camera_3d: Camera3D
var _world_container: Node3D
var _gizmo_3d: Node3D
var _baseplate_mesh: MeshInstance3D

# Docks & Dialogs
var _hierarchy_dock = null
var _inspector_dock = null
var _collections_dock = null
var _simulation_mgr = null
var _help_dialog = null
var _status_bar_label: Label
var _is_built: bool = false


func _init() -> void:
	name = "StudioMain"
	if not _is_built:
		_init_core_model()
		_build_studio_layout()


func _ready() -> void:
	if not _is_built:
		_init_core_model()
		_build_studio_layout()
	_setup_shortcuts()
	_parse_cmdline_arguments()

	# If the world has no objects yet, load the Baseplate starter template automatically
	if core != null and core.model != null and core.model.payload.objects.is_empty():
		load_template("baseplate")

	# Show Help & Quick Start Guide on first launch if enabled in settings
	if _help_dialog != null and StudioHelpDialogClass.should_show_on_startup():
		_help_dialog.visible = true
		_help_dialog.move_to_front()


func _init_core_model() -> void:
	var payload := ChunkDataDecoder.ChunkPayload.new()
	var layer := ChunkDataDecoder.TileLayerData.new()
	layer.name = "ground"
	layer.layer_id = 0
	layer.width = 32
	layer.height = 32
	layer.depth = 1
	layer.tiles = PackedInt32Array()
	layer.tiles.resize(32 * 32)
	payload.tile_layers.append(layer)

	var model := ChunkEditorModel.new(payload)
	var catalog := EditorObjectCatalog.new()
	catalog.load_catalog()
	core = EditorCore.new(model, catalog)


func _build_studio_layout() -> void:
	if _is_built:
		return
	_is_built = true
	set_anchors_preset(Control.PRESET_FULL_RECT)

	var bg := ColorRect.new()
	bg.set_anchors_preset(Control.PRESET_FULL_RECT)
	bg.color = Color(0.13, 0.14, 0.17)
	add_child(bg)

	var main_vbox := VBoxContainer.new()
	main_vbox.set_anchors_preset(Control.PRESET_FULL_RECT)
	add_child(main_vbox)

	# 1. Top Menu Bar
	_build_top_menu_bar(main_vbox)

	# 2. Main Action Toolbar (Tools, Snap, Quick Insert, Simulation, Help)
	_build_toolbar(main_vbox)

	# 3. Center Workspace (Horizontal Split: Left Dock | Center Viewport | Right Docks)
	var workspace_hbox := HBoxContainer.new()
	workspace_hbox.size_flags_vertical = Control.SIZE_EXPAND_FILL
	main_vbox.add_child(workspace_hbox)

	# Left Dock: Scene Hierarchy
	var left_panel := PanelContainer.new()
	left_panel.custom_minimum_size = Vector2(240, 0)
	left_panel.size_flags_vertical = Control.SIZE_EXPAND_FILL
	_hierarchy_dock = StudioHierarchyDockClass.new()
	_hierarchy_dock.setup(core)
	left_panel.add_child(_hierarchy_dock)
	workspace_hbox.add_child(left_panel)

	# Center: 3D Viewport with interactive picking & drop support
	_vp_container = StudioViewportContainer.new()
	_vp_container.studio_main = self
	_vp_container.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	_vp_container.size_flags_vertical = Control.SIZE_EXPAND_FILL
	_vp_container.stretch = true
	workspace_hbox.add_child(_vp_container)

	_sub_viewport = SubViewport.new()
	_sub_viewport.handle_input_locally = true
	_vp_container.add_child(_sub_viewport)

	_setup_3d_viewport_scene(_sub_viewport)
	_setup_viewport_hud_overlay(_vp_container)

	# Right Dock: TabContainer with Inspector & Collections
	var right_panel := PanelContainer.new()
	right_panel.custom_minimum_size = Vector2(300, 0)
	right_panel.size_flags_vertical = Control.SIZE_EXPAND_FILL
	var tabs := TabContainer.new()
	tabs.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	tabs.size_flags_vertical = Control.SIZE_EXPAND_FILL

	_inspector_dock = StudioInspectorDockClass.new()
	_inspector_dock.setup(core)
	tabs.add_child(_inspector_dock)
	tabs.set_tab_title(0, "Inspector")

	_collections_dock = StudioCollectionsDockClass.new()
	_collections_dock.model_selected.connect(_on_collection_model_selected)
	tabs.add_child(_collections_dock)
	tabs.set_tab_title(1, "Collections")

	right_panel.add_child(tabs)
	workspace_hbox.add_child(right_panel)

	# 4. Bottom Status Bar
	var status_panel := PanelContainer.new()
	status_panel.custom_minimum_size = Vector2(0, 24)
	_status_bar_label = Label.new()
	_status_bar_label.text = "ModBison Studio Ready | Baseplate Loaded | Press [F1] for Quick Start Guide"
	_status_bar_label.add_theme_font_size_override("font_size", 10)
	status_panel.add_child(_status_bar_label)
	main_vbox.add_child(status_panel)

	# Simulation Manager
	_simulation_mgr = StudioSimulationManagerClass.new()
	_simulation_mgr.setup(core, _world_container)
	_simulation_mgr.simulation_started.connect(func(_m): _update_simulation_ui(true))
	_simulation_mgr.simulation_stopped.connect(func(): _update_simulation_ui(false))
	add_child(_simulation_mgr)

	# Help Dialog Overlay
	_help_dialog = StudioHelpDialogClass.new()
	_help_dialog.visible = false
	_help_dialog.set_anchors_preset(Control.PRESET_CENTER)
	add_child(_help_dialog)


func _build_top_menu_bar(parent: Control) -> void:
	_menu_bar = MenuBar.new()
	_menu_bar.custom_minimum_size = Vector2(0, 28)

	# File Menu
	var file_menu := PopupMenu.new()
	file_menu.name = "File"
	file_menu.add_item("New Project (Baseplate)", 0, KEY_MASK_CTRL | KEY_N)
	file_menu.add_item("Open Project...", 1, KEY_MASK_CTRL | KEY_O)
	file_menu.add_separator()
	file_menu.add_item("Save Project (Ctrl+S)", 2, KEY_MASK_CTRL | KEY_S)
	file_menu.add_item("Save As...", 3)
	file_menu.add_separator()
	file_menu.add_item("Publish to Cloud...", 4)
	file_menu.add_separator()
	file_menu.add_item("Return to Main Menu", 5)
	file_menu.add_item("Exit Studio (Quit)", 6)
	file_menu.id_pressed.connect(_on_file_menu_pressed)
	_menu_bar.add_child(file_menu)

	# Edit Menu
	var edit_menu := PopupMenu.new()
	edit_menu.name = "Edit"
	edit_menu.add_item("Undo", 0, KEY_MASK_CTRL | KEY_Z)
	edit_menu.add_item("Redo", 1, KEY_MASK_CTRL | KEY_Y)
	edit_menu.add_separator()
	edit_menu.add_item("Duplicate", 2, KEY_MASK_CTRL | KEY_D)
	edit_menu.add_item("Delete", 3, KEY_DELETE)
	edit_menu.id_pressed.connect(_on_edit_menu_pressed)
	_menu_bar.add_child(edit_menu)

	# View Menu
	var view_menu := PopupMenu.new()
	view_menu.name = "View"
	view_menu.add_item("Perspective", 0, KEY_P)
	view_menu.add_item("Top View", 1, KEY_7)
	view_menu.add_item("Front View", 2, KEY_1)
	view_menu.add_item("Side View", 3, KEY_3)
	view_menu.add_separator()
	view_menu.add_item("Focus Selection", 4, KEY_F)
	view_menu.id_pressed.connect(_on_view_menu_pressed)
	_menu_bar.add_child(view_menu)

	# Model Menu
	var model_menu := PopupMenu.new()
	model_menu.name = "Model"
	model_menu.add_item("Add ModBison", 0)
	model_menu.add_item("Add Wooden Crate", 1)
	model_menu.add_item("Add Pine Tree", 2)
	model_menu.add_item("Add Street Lamp", 3)
	model_menu.add_item("Add Treasure Chest", 4)
	model_menu.add_item("Add Buffalo Chip Coin", 5)
	model_menu.id_pressed.connect(_on_model_menu_pressed)
	_menu_bar.add_child(model_menu)

	# Test Menu
	var test_menu := PopupMenu.new()
	test_menu.name = "Test"
	test_menu.add_item("Play Solo", 0, KEY_F5)
	test_menu.add_item("Run Simulation", 1, KEY_F6)
	test_menu.add_item("Stop Playtest", 2, KEY_MASK_SHIFT | KEY_F5)
	test_menu.id_pressed.connect(_on_test_menu_pressed)
	_menu_bar.add_child(test_menu)

	# Publish Menu
	var pub_menu := PopupMenu.new()
	pub_menu.name = "Publish"
	pub_menu.add_item("Export .mbworld Package", 0)
	pub_menu.add_item("Sync to Game Server", 1)
	pub_menu.id_pressed.connect(_on_publish_menu_pressed)
	_menu_bar.add_child(pub_menu)

	# Help Menu
	var help_menu := PopupMenu.new()
	help_menu.name = "Help"
	help_menu.add_item("Quick Start Guide (F1)", 0, KEY_F1)
	help_menu.add_item("Keyboard & Mouse Controls", 1)
	help_menu.add_separator()
	help_menu.add_item("Reset Camera to Center", 2)
	help_menu.id_pressed.connect(_on_help_menu_pressed)
	_menu_bar.add_child(help_menu)

	parent.add_child(_menu_bar)


func _build_toolbar(parent: Control) -> void:
	_toolbar = HBoxContainer.new()
	_toolbar.custom_minimum_size = Vector2(0, 36)
	_toolbar.add_theme_constant_override("separation", 6)

	_btn_select = _add_tool_btn("↖ [1] Select", func(): _set_gizmo_mode(TransformGizmo3DClass.Mode.NONE))
	_btn_move = _add_tool_btn("✛ [2] Move", func(): _set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE))
	_btn_rotate = _add_tool_btn("↻ [3] Rotate", func(): _set_gizmo_mode(TransformGizmo3DClass.Mode.ROTATE))
	_btn_scale = _add_tool_btn("⤢ [4] Scale", func(): _set_gizmo_mode(TransformGizmo3DClass.Mode.SCALE))

	var vsep1 := VSeparator.new()
	_toolbar.add_child(vsep1)

	var snap_lbl := Label.new()
	snap_lbl.text = "Snap:"
	snap_lbl.add_theme_font_size_override("font_size", 10)
	_toolbar.add_child(snap_lbl)

	_snap_spin = SpinBox.new()
	_snap_spin.min_value = 0.1
	_snap_spin.max_value = 10.0
	_snap_spin.step = 0.5
	_snap_spin.value = 1.0
	_snap_spin.value_changed.connect(func(v):
		if _gizmo_3d != null:
			_gizmo_3d.snap_translate = v
	)
	_toolbar.add_child(_snap_spin)

	var vsep2 := VSeparator.new()
	_toolbar.add_child(vsep2)

	# Quick Insert Bar
	var add_lbl := Label.new()
	add_lbl.text = "+ Quick Add:"
	add_lbl.add_theme_font_size_override("font_size", 10)
	add_lbl.add_theme_color_override("font_color", Color(1.0, 0.9, 0.4))
	_toolbar.add_child(add_lbl)

	_add_quick_insert_btn("🦬 Bison", "bison", "ModBison")
	_add_quick_insert_btn("📦 Crate", "crate_small", "Wooden Crate")
	_add_quick_insert_btn("🌲 Tree", "tree_pine_01", "Pine Tree")
	_add_quick_insert_btn("💡 Lamp", "lamp_post_01", "Street Lamp")

	var spacer := Control.new()
	spacer.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	_toolbar.add_child(spacer)

	# Simulation Controls
	_btn_play = Button.new()
	_btn_play.text = "▶ Play (F5)"
	_btn_play.add_theme_color_override("font_color", Color(0.3, 0.9, 0.4))
	_btn_play.pressed.connect(func(): _simulation_mgr.start_play(true))
	_toolbar.add_child(_btn_play)

	_btn_stop = Button.new()
	_btn_stop.text = "⏹ Stop"
	_btn_stop.add_theme_color_override("font_color", Color(1.0, 0.4, 0.4))
	_btn_stop.disabled = true
	_btn_stop.pressed.connect(func(): _simulation_mgr.stop_simulation())
	_toolbar.add_child(_btn_stop)

	var vsep3 := VSeparator.new()
	_toolbar.add_child(vsep3)

	# Help & Return to Main Menu
	var btn_help := Button.new()
	btn_help.text = "❓ Help & Guide (F1)"
	btn_help.add_theme_color_override("font_color", Color(1.0, 0.9, 0.3))
	btn_help.tooltip_text = "Open Quick Start Guide and Controls Reference (F1)"
	btn_help.pressed.connect(func(): _toggle_help_dialog())
	_toolbar.add_child(btn_help)

	var btn_home := Button.new()
	btn_home.text = "🏠 Main Menu"
	btn_home.add_theme_color_override("font_color", Color(0.82, 0.86, 0.95))
	btn_home.tooltip_text = "Return to ModBison Main Menu"
	btn_home.pressed.connect(_return_to_main_menu)
	_toolbar.add_child(btn_home)

	parent.add_child(_toolbar)


func _add_tool_btn(text: String, callback: Callable) -> Button:
	var btn := Button.new()
	btn.text = text
	btn.pressed.connect(callback)
	_toolbar.add_child(btn)
	return btn


func _add_quick_insert_btn(btn_text: String, cat_id: String, display_name: String) -> Button:
	var btn := Button.new()
	btn.text = btn_text
	btn.custom_minimum_size = Vector2(0, 26)
	btn.tooltip_text = "Spawn %s into the world at camera focus point" % display_name
	btn.pressed.connect(func(): _quick_insert(cat_id, display_name))
	_toolbar.add_child(btn)
	return btn


func _quick_insert(cat_id: String, display_name: String) -> void:
	var spawn_pos: Vector3 = Vector3.ZERO
	if _camera_3d != null:
		spawn_pos = _camera_3d.focal_point
		spawn_pos.y = 0.0
	var new_id := core.place_object(cat_id, spawn_pos, Vector4(0, 0, 0, 1), Vector3.ONE, {
		"display_name": display_name,
		"catalog_id": cat_id
	})
	if new_id != "":
		core.select_object(new_id)
		_spawn_visual_node(new_id)
		_hierarchy_dock.refresh_tree()
		_set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE)
		_status_bar_label.text = "Spawned %s at (%.1f, 0, %.1f) | ✛ Move gizmo active" % [display_name, spawn_pos.x, spawn_pos.z]


func _setup_3d_viewport_scene(vp: SubViewport) -> void:
	# World Environment
	var env := WorldEnvironment.new()
	var environment := Environment.new()
	environment.background_mode = Environment.BG_COLOR
	environment.background_color = Color(0.18, 0.22, 0.28)
	environment.ambient_light_source = Environment.AMBIENT_SOURCE_COLOR
	environment.ambient_light_color = Color(0.65, 0.65, 0.7)
	env.environment = environment
	vp.add_child(env)

	# Directional Sun Light
	var sun := DirectionalLight3D.new()
	sun.rotation_degrees = Vector3(-45, 30, 0)
	sun.shadow_enabled = true
	vp.add_child(sun)

	# Studio Baseplate Ground Mesh
	_baseplate_mesh = MeshInstance3D.new()
	var plane := PlaneMesh.new()
	plane.size = Vector2(64, 64)
	var gmat := StandardMaterial3D.new()
	gmat.albedo_color = Color(0.20, 0.23, 0.27)
	gmat.roughness = 0.85
	_baseplate_mesh.mesh = plane
	vp.add_child(_baseplate_mesh)

	# 3D Grid floor lines
	var grid := _create_3d_grid(32, 1.0)
	vp.add_child(grid)

	# Camera
	_camera_3d = StudioViewportCameraClass.new()
	vp.add_child(_camera_3d)

	# World Object Container
	_world_container = Node3D.new()
	_world_container.name = "WorldContainer"
	vp.add_child(_world_container)

	# Interactive Gizmo
	_gizmo_3d = TransformGizmo3DClass.new()
	_gizmo_3d.name = "TransformGizmo3D"
	vp.add_child(_gizmo_3d)

	core.selection.selection_changed.connect(_on_selection_changed)


func _setup_viewport_hud_overlay(parent: Control) -> void:
	var hud_bar := PanelContainer.new()
	var h_style := StyleBoxFlat.new()
	h_style.bg_color = Color(0.08, 0.10, 0.14, 0.88)
	h_style.border_color = Color(0.3, 0.45, 0.6, 0.6)
	h_style.set_border_width_all(1)
	h_style.set_corner_radius_all(6)
	h_style.content_margin_left = 12
	h_style.content_margin_right = 12
	h_style.content_margin_top = 6
	h_style.content_margin_bottom = 6
	hud_bar.add_theme_stylebox_override("panel", h_style)
	hud_bar.mouse_filter = Control.MOUSE_FILTER_IGNORE
	hud_bar.set_anchors_preset(Control.PRESET_BOTTOM_LEFT)
	hud_bar.position = Vector2(16, -42)

	var hud_text := Label.new()
	hud_text.text = "🎥 RMB+WASD: Fly  |  🖱️ LMB: Click to Select  |  ✛ [2] Move  |  ↻ [3] Rotate  |  [F] Focus  |  ▶ [F5] Play  |  ❓ [F1] Help"
	hud_text.add_theme_font_size_override("font_size", 11)
	hud_text.add_theme_color_override("font_color", Color(0.9, 0.92, 0.96))
	hud_bar.add_child(hud_text)
	parent.add_child(hud_bar)


func _create_3d_grid(size: int, step: float) -> Node3D:
	var mi := MeshInstance3D.new()
	var imm := ImmediateMesh.new()
	var mat := StandardMaterial3D.new()
	mat.albedo_color = Color(0.35, 0.42, 0.5, 0.6)
	mat.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED

	imm.surface_begin(Mesh.PRIMITIVE_LINES, mat)
	var half := (size * step) / 2.0
	for i in range(-size / 2, size / 2 + 1):
		var p := i * step
		imm.surface_add_vertex(Vector3(p, 0.01, -half))
		imm.surface_add_vertex(Vector3(p, 0.01, half))
		imm.surface_add_vertex(Vector3(-half, 0.01, p))
		imm.surface_add_vertex(Vector3(half, 0.01, p))
	imm.surface_end()
	mi.mesh = imm
	return mi


func _setup_shortcuts() -> void:
	set_process_unhandled_key_input(true)


func _unhandled_key_input(event: InputEvent) -> void:
	var k := event as InputEventKey
	if not k.pressed or k.echo:
		return

	if k.is_command_or_control_pressed():
		if k.keycode == KEY_Z:
			core.undo()
			_refresh_scene_visuals()
		elif k.keycode == KEY_Y:
			core.redo()
			_refresh_scene_visuals()
		elif k.keycode == KEY_S:
			save_current_project()
		elif k.keycode == KEY_D:
			_hierarchy_dock._on_duplicate_pressed()
	elif k.keycode == KEY_F1:
		_toggle_help_dialog()
	elif k.keycode == KEY_F5:
		if _simulation_mgr.is_playing():
			_simulation_mgr.stop_simulation()
		else:
			_simulation_mgr.start_play(true)
	elif k.keycode == KEY_1 and not k.is_command_or_control_pressed():
		_set_gizmo_mode(TransformGizmo3DClass.Mode.NONE)
	elif k.keycode == KEY_2 and not k.is_command_or_control_pressed():
		_set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE)
	elif k.keycode == KEY_3 and not k.is_command_or_control_pressed():
		_set_gizmo_mode(TransformGizmo3DClass.Mode.ROTATE)
	elif k.keycode == KEY_4 and not k.is_command_or_control_pressed():
		_set_gizmo_mode(TransformGizmo3DClass.Mode.SCALE)
	elif k.keycode == KEY_F and not k.is_command_or_control_pressed():
		var sel_id = core.selection.get_selected_id() if core.selection.has_method("get_selected_id") else ""
		if sel_id != "":
			var n = _world_container.get_node_or_null(sel_id)
			if n is Node3D and _camera_3d != null:
				_camera_3d.focus_on(n.global_position)


func _set_gizmo_mode(mode: TransformGizmo3DClass.Mode) -> void:
	if _gizmo_3d != null:
		_gizmo_3d.set_mode(mode)
	var mode_name := "Select"
	match mode:
		TransformGizmo3DClass.Mode.TRANSLATE: mode_name = "Move (✛)"
		TransformGizmo3DClass.Mode.ROTATE: mode_name = "Rotate (↻)"
		TransformGizmo3DClass.Mode.SCALE: mode_name = "Scale (⤢)"
	_status_bar_label.text = "Tool: %s | Snap: %.1fm | [F1] Help" % [mode_name, _snap_spin.value if _snap_spin else 1.0]


func _toggle_help_dialog() -> void:
	if _help_dialog == null:
		return
	_help_dialog.visible = not _help_dialog.visible
	if _help_dialog.visible:
		_help_dialog.move_to_front()


func _return_to_main_menu() -> void:
	if _simulation_mgr != null and _simulation_mgr.is_playing():
		_simulation_mgr.stop_simulation()
	get_tree().change_scene_to_file("res://scenes/main_menu.tscn")


# ── Interactive 3D Viewport Input & Raycast Picking ─────────────────────

func handle_viewport_input(event: InputEvent) -> void:
	if event is InputEventMouseButton:
		var mb := event as InputEventMouseButton
		if mb.button_index == MOUSE_BUTTON_LEFT and mb.pressed:
			var hit_obj := _raycast_find_object(mb.position)
			if hit_obj != null:
				core.select_object(hit_obj.name)
				if mb.double_click and _camera_3d != null:
					_camera_3d.focus_on(hit_obj.global_position)
				_status_bar_label.text = "Selected: %s | ✛ Drag handles or [2-4] switch tools" % hit_obj.name
			else:
				core.select_object("")
				_status_bar_label.text = "Deselected | Click an object or [+ Add] to build"


func handle_viewport_drop(at_pos: Vector2, data: Variant) -> void:
	if not (data is Dictionary):
		return
	var cat_id := str(data.get("catalog_id", "crate_small"))
	var drop_pos := _raycast_ground_plane(at_pos)
	var target_obj := _raycast_find_object(at_pos)
	var new_id: String = ""

	if target_obj != null and target_obj.name != "":
		new_id = core.place_object_stacked(cat_id, target_obj.name, drop_pos, Vector3(0, 0, 1), 0.0, false, {
			"display_name": data.get("name", cat_id),
			"catalog_id": cat_id,
			"asset_id": data.get("asset_id", "")
		})
	else:
		new_id = core.place_object(cat_id, drop_pos, Vector4(0, 0, 0, 1), Vector3.ONE, {
			"display_name": data.get("name", cat_id),
			"catalog_id": cat_id,
			"asset_id": data.get("asset_id", "")
		})

	if new_id != "":
		core.select_object(new_id)
		_spawn_visual_node(new_id)
		_hierarchy_dock.refresh_tree()
		_set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE)
		_status_bar_label.text = "Placed %s at (%.1f, %.1f, %.1f)" % [data.get("name", cat_id), drop_pos.x, drop_pos.y, drop_pos.z]


func _raycast_find_object(screen_pos: Vector2) -> Node3D:
	if _camera_3d == null or _world_container == null:
		return null
	var from: Vector3 = _camera_3d.project_ray_origin(screen_pos)
	var dir: Vector3 = _camera_3d.project_ray_normal(screen_pos)

	# 1. Physics raycast against colliders in viewport world
	if _sub_viewport != null and _sub_viewport.world_3d != null:
		var space = _sub_viewport.world_3d.direct_space_state
		var query := PhysicsRayQueryParameters3D.create(from, from + dir * 500.0)
		var res := space.intersect_ray(query)
		if not res.is_empty() and res.collider != null:
			var curr: Node = res.collider
			while curr != null and curr != _world_container:
				if curr.get_parent() == _world_container and curr is Node3D:
					return curr as Node3D
				curr = curr.get_parent()

	# 2. Geometric fallback (ray-to-object closest distance)
	var best_node: Node3D = null
	var best_dist: float = 1e9
	for child in _world_container.get_children():
		if not (child is Node3D):
			continue
		var obj_pos: Vector3 = (child as Node3D).global_position
		var to_obj: Vector3 = obj_pos - from
		var proj: float = to_obj.dot(dir)
		if proj < 0.2:
			continue
		var closest: Vector3 = from + dir * proj
		var dist: float = closest.distance_to(obj_pos)
		if dist < 1.8 and proj < best_dist:
			best_dist = proj
			best_node = child as Node3D
	return best_node


func _raycast_ground_plane(screen_pos: Vector2) -> Vector3:
	if _camera_3d == null:
		return Vector3.ZERO
	var from: Vector3 = _camera_3d.project_ray_origin(screen_pos)
	var dir: Vector3 = _camera_3d.project_ray_normal(screen_pos)
	if absf(dir.y) < 0.0001:
		return from + dir * 10.0
	var t: float = -from.y / dir.y
	if t < 0.0:
		return from + dir * 10.0
	return from + dir * t


# ── Selection & Scene Visual Sync ─────────────────────────────────────

func _on_selection_changed(obj_id: String) -> void:
	if obj_id == "":
		_gizmo_3d.attach_to_node(null)
		return

	var obj_node = _world_container.get_node_or_null(obj_id)
	if obj_node is Node3D:
		_gizmo_3d.attach_to_node(obj_node)
		_camera_3d.focus_on(obj_node.global_position)


func _on_collection_model_selected(model_data: Dictionary) -> void:
	var cat_id := str(model_data.get("catalog_id", "crate_small"))
	var spawn_pos: Vector3 = Vector3.ZERO
	if _camera_3d != null:
		spawn_pos = _camera_3d.focal_point
		spawn_pos.y = 0.0
	var new_id := core.place_object(cat_id, spawn_pos, Vector4(0, 0, 0, 1), Vector3.ONE, {
		"display_name": model_data.get("name", cat_id),
		"catalog_id": cat_id,
		"asset_id": model_data.get("asset_id", "")
	})
	if new_id != "":
		core.select_object(new_id)
		_spawn_visual_node(new_id)
		_hierarchy_dock.refresh_tree()
		_set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE)
		_status_bar_label.text = "Placed %s at (%.1f, 0, %.1f)" % [model_data.get("name", cat_id), spawn_pos.x, spawn_pos.z]


func _spawn_visual_node(obj_id: String) -> void:
	var obj = core.model.find_object(obj_id)
	if obj == null:
		return
	var wo := WorldObjectClass.new()
	wo.id = obj.id
	wo.type = obj.type
	wo.asset_id = obj.asset_id
	wo.position = obj.position
	wo.properties = obj.properties.duplicate(true)

	var node = StaticObjectNodeClass.new()
	node.name = obj.id
	node.world_object = wo
	node.position = Vector3(obj.position.x, obj.position.z, obj.position.y)
	_world_container.add_child(node)


func _refresh_scene_visuals() -> void:
	for c in _world_container.get_children():
		c.queue_free()
	for obj in core.model.payload.objects:
		_spawn_visual_node(obj.id)
	_hierarchy_dock.refresh_tree()


# ── Templates & Project IO ───────────────────────────────────────────

func load_template(template_name: String) -> void:
	var data := MBWorldProjectIOClass.create_template(template_name)
	project_title = data.get("title", "Untitled World")
	for obj in data.get("objects", []):
		var p: Array = obj.get("position", [0, 0, 0])
		var r: Array = obj.get("rotation", [0, 0, 0, 1])
		var s: Array = obj.get("scale", [1, 1, 1])
		core.place_object(
			obj.get("catalog_id", "crate_small"),
			Vector3(p[0], p[1], p[2]),
			Vector4(r[0], r[1], r[2], r[3]),
			Vector3(s[0], s[1], s[2]),
			obj.get("properties", {})
		)
	_refresh_scene_visuals()
	# Select mascot or first object to showcase inspector & gizmo
	if not core.model.payload.objects.is_empty():
		core.select_object(core.model.payload.objects[0].id)
		_set_gizmo_mode(TransformGizmo3DClass.Mode.TRANSLATE)
	_status_bar_label.text = "Loaded template: %s | Press [F1] for Controls" % project_title


func save_current_project(path: String = "") -> bool:
	if path == "":
		path = "user://saved_world.mbworld"
	var data := {
		"title": project_title,
		"objects": []
	}
	for obj in core.model.payload.objects:
		data["objects"].append({
			"id": obj.id,
			"catalog_id": obj.properties.get("catalog_id", "crate_small"),
			"asset_id": obj.asset_id,
			"position": [obj.position.x, obj.position.y, obj.position.z],
			"rotation": [obj.rotation.x, obj.rotation.y, obj.rotation.z, obj.rotation.w],
			"scale": [obj.scale.x, obj.scale.y, obj.scale.z],
			"properties": obj.properties
		})
	var ok := MBWorldProjectIOClass.save_project(path, data)
	if ok:
		_status_bar_label.text = "Saved world project to %s" % path
	return ok


func _update_simulation_ui(playing: bool) -> void:
	_btn_play.disabled = playing
	_btn_stop.disabled = not playing
	_status_bar_label.text = "Simulation: PLAYING (F5 to Stop)" if playing else "Simulation: STOPPED (Edit mode)"


# ── Menu Bar Dispatch ────────────────────────────────────────────────

func _on_file_menu_pressed(id: int) -> void:
	match id:
		0: load_template("baseplate")
		2: save_current_project()
		3: save_current_project("user://saved_world_as.mbworld")
		4: save_current_project("user://published_world.mbworld")
		5: _return_to_main_menu()
		6: get_tree().quit(0)


func _on_edit_menu_pressed(id: int) -> void:
	match id:
		0: core.undo(); _refresh_scene_visuals()
		1: core.redo(); _refresh_scene_visuals()
		2: _hierarchy_dock._on_duplicate_pressed()
		3: _hierarchy_dock._on_delete_pressed()


func _on_view_menu_pressed(id: int) -> void:
	match id:
		0: _camera_3d.set_view_preset(StudioViewportCameraClass.ViewPreset.PERSPECTIVE)
		1: _camera_3d.set_view_preset(StudioViewportCameraClass.ViewPreset.TOP)
		2: _camera_3d.set_view_preset(StudioViewportCameraClass.ViewPreset.FRONT)
		3: _camera_3d.set_view_preset(StudioViewportCameraClass.ViewPreset.SIDE)
		4:
			var sel_id = core.selection.get_selected_id() if core.selection.has_method("get_selected_id") else ""
			if sel_id != "":
				var n = _world_container.get_node_or_null(sel_id)
				if n is Node3D and _camera_3d != null:
					_camera_3d.focus_on(n.global_position)


func _on_model_menu_pressed(id: int) -> void:
	var cat_info := [
		{"catalog_id": "bison", "name": "ModBison"},
		{"catalog_id": "crate_small", "name": "Wooden Crate"},
		{"catalog_id": "tree_pine_01", "name": "Pine Tree"},
		{"catalog_id": "lamp_post_01", "name": "Street Lamp"},
		{"catalog_id": "chest_01", "name": "Treasure Chest"},
		{"catalog_id": "buffalo_chip_coin", "name": "Buffalo Chip Coin"}
	]
	if id >= 0 and id < cat_info.size():
		_quick_insert(cat_info[id]["catalog_id"], cat_info[id]["name"])


func _on_test_menu_pressed(id: int) -> void:
	match id:
		0: _simulation_mgr.start_play(true)
		1: _simulation_mgr.start_play(false)
		2: _simulation_mgr.stop_simulation()


func _on_publish_menu_pressed(id: int) -> void:
	if id == 0:
		save_current_project("user://exported_world.mbworld")


func _on_help_menu_pressed(id: int) -> void:
	match id:
		0, 1: _toggle_help_dialog()
		2:
			if _camera_3d != null:
				_camera_3d.focus_on(Vector3.ZERO, 5.0)


func _parse_cmdline_arguments() -> void:
	var args := OS.get_cmdline_args()
	for i in range(args.size()):
		var arg := args[i]
		if arg == "--template" and i + 1 < args.size():
			load_template(args[i + 1])
		elif arg.ends_with(".mbworld") and FileAccess.file_exists(arg):
			var d := MBWorldProjectIOClass.load_project(arg)
			if not d.is_empty():
				project_title = d.get("title", "Loaded World")