/* $Id$ */

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file group_gui.cpp GUI for the group window. */

#include "stdafx.h"
#include "openttd.h"
#include "textbuf_gui.h"
#include "command_func.h"
#include "vehicle_gui.h"
#include "vehicle_base.h"
#include "group.h"
#include "strings_func.h"
#include "window_func.h"
#include "vehicle_func.h"
#include "autoreplace_gui.h"
#include "company_func.h"
#include "widgets/dropdown_type.h"
#include "widgets/dropdown_func.h"
#include "tilehighlight_func.h"
#include "vehicle_gui_base.h"
#include "core/geometry_func.hpp"
#include "company_base.h"

#include "table/strings.h"
#include "table/sprites.h"

typedef GUIList<const Group*> GUIGroupList;

enum GroupListWidgets {
	GRP_WIDGET_CAPTION,
	GRP_WIDGET_SORT_BY_ORDER,
	GRP_WIDGET_SORT_BY_DROPDOWN,
	GRP_WIDGET_LIST_VEHICLE,
	GRP_WIDGET_LIST_VEHICLE_SCROLLBAR,
	GRP_WIDGET_AVAILABLE_VEHICLES,
	GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN,
	GRP_WIDGET_STOP_ALL,
	GRP_WIDGET_START_ALL,

	GRP_WIDGET_ALL_VEHICLES,
	GRP_WIDGET_DEFAULT_VEHICLES,
	GRP_WIDGET_LIST_GROUP,
	GRP_WIDGET_LIST_GROUP_SCROLLBAR,
	GRP_WIDGET_CREATE_GROUP,
	GRP_WIDGET_DELETE_GROUP,
	GRP_WIDGET_RENAME_GROUP,
	GRP_WIDGET_REPLACE_PROTECTION,
};

enum GroupActionListFunction {
	GALF_REPLACE,
	GALF_SERVICE,
	GALF_DEPOT,
	GALF_ADD_SHARED,
	GALF_REMOVE_ALL,
};

/**
 * Update/redraw the group action dropdown
 * @param w   the window the dropdown belongs to
 * @param gid the currently selected group in the window
 */
static void ShowGroupActionDropdown(Window *w, GroupID gid)
{
	DropDownList *list = new DropDownList();

	list->push_back(new DropDownListStringItem(STR_VEHICLE_LIST_REPLACE_VEHICLES,    GALF_REPLACE, false));
	list->push_back(new DropDownListStringItem(STR_VEHICLE_LIST_SEND_FOR_SERVICING,  GALF_SERVICE, false));
	list->push_back(new DropDownListStringItem(STR_VEHICLE_LIST_SEND_TRAIN_TO_DEPOT, GALF_DEPOT,   false));

	if (Group::IsValidID(gid)) {
		list->push_back(new DropDownListStringItem(STR_GROUP_ADD_SHARED_VEHICLE,  GALF_ADD_SHARED, false));
		list->push_back(new DropDownListStringItem(STR_GROUP_REMOVE_ALL_VEHICLES, GALF_REMOVE_ALL, false));
	}

	ShowDropDownList(w, list, 0, GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN);
}

static const NWidgetPart _nested_group_widgets[] = {
	NWidget(NWID_HORIZONTAL), // Window header
		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
		NWidget(WWT_CAPTION, COLOUR_GREY, GRP_WIDGET_CAPTION),
		NWidget(WWT_SHADEBOX, COLOUR_GREY),
		NWidget(WWT_STICKYBOX, COLOUR_GREY),
	EndContainer(),
	NWidget(NWID_HORIZONTAL),
		/* left part */
		NWidget(NWID_VERTICAL),
			NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalTextLines(1, WD_DROPDOWNTEXT_TOP + WD_DROPDOWNTEXT_BOTTOM), SetFill(1, 0), EndContainer(),
			NWidget(WWT_PANEL, COLOUR_GREY, GRP_WIDGET_ALL_VEHICLES), SetMinimalSize(200, 13), SetFill(1, 0), EndContainer(),
			NWidget(WWT_PANEL, COLOUR_GREY, GRP_WIDGET_DEFAULT_VEHICLES), SetMinimalSize(200, 13), SetFill(1, 0), EndContainer(),
			NWidget(NWID_HORIZONTAL),
				NWidget(WWT_MATRIX, COLOUR_GREY, GRP_WIDGET_LIST_GROUP), SetMinimalSize(188, 0), SetDataTip(0x701, STR_GROUPS_CLICK_ON_GROUP_FOR_TOOLTIP),
						SetFill(1, 0), SetResize(0, 1),
				NWidget(WWT_SCROLL2BAR, COLOUR_GREY, GRP_WIDGET_LIST_GROUP_SCROLLBAR),
			EndContainer(),
			NWidget(NWID_HORIZONTAL),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_CREATE_GROUP), SetMinimalSize(24, 25), SetFill(0, 1),
						SetDataTip(SPR_GROUP_CREATE_TRAIN, STR_GROUP_CREATE_TOOLTIP),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_DELETE_GROUP), SetMinimalSize(24, 25), SetFill(0, 1),
						SetDataTip(SPR_GROUP_DELETE_TRAIN, STR_GROUP_DELETE_TOOLTIP),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_RENAME_GROUP), SetMinimalSize(24, 25), SetFill(0, 1),
						SetDataTip(SPR_GROUP_RENAME_TRAIN, STR_GROUP_RENAME_TOOLTIP),
				NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalSize(92, 25), SetFill(1, 1), EndContainer(),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_REPLACE_PROTECTION), SetMinimalSize(24, 25), SetFill(0, 1),
						SetDataTip(SPR_GROUP_REPLACE_OFF_TRAIN, STR_GROUP_REPLACE_PROTECTION_TOOLTIP),
				NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalSize(12, 25), SetFill(0, 1), EndContainer(),
			EndContainer(),
		EndContainer(),
		/* right part */
		NWidget(NWID_VERTICAL),
			NWidget(NWID_HORIZONTAL),
				NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, GRP_WIDGET_SORT_BY_ORDER), SetMinimalSize(81, 12), SetDataTip(STR_BUTTON_SORT_BY, STR_TOOLTIP_SORT_ORDER),
				NWidget(WWT_DROPDOWN, COLOUR_GREY, GRP_WIDGET_SORT_BY_DROPDOWN), SetMinimalSize(167, 12), SetDataTip(0x0, STR_TOOLTIP_SORT_CRITERIAP),
				NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalSize(12, 12), SetResize(1, 0), EndContainer(),
			EndContainer(),
			NWidget(NWID_HORIZONTAL),
				NWidget(WWT_MATRIX, COLOUR_GREY, GRP_WIDGET_LIST_VEHICLE), SetMinimalSize(248, 0), SetDataTip(0x701, STR_NULL), SetResize(1, 1), SetFill(1, 0),
				NWidget(WWT_SCROLLBAR, COLOUR_GREY, GRP_WIDGET_LIST_VEHICLE_SCROLLBAR),
			EndContainer(),
			NWidget(NWID_HORIZONTAL),
				NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, GRP_WIDGET_AVAILABLE_VEHICLES), SetMinimalSize(106, 12), SetFill(0, 1),
						SetDataTip(0x0, STR_VEHICLE_LIST_AVAILABLE_ENGINES_TOOLTIP),
				NWidget(WWT_DROPDOWN, COLOUR_GREY, GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN), SetMinimalSize(118, 12), SetFill(0, 1),
						SetDataTip(STR_VEHICLE_LIST_MANAGE_LIST, STR_VEHICLE_LIST_MANAGE_LIST_TOOLTIP),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_STOP_ALL), SetMinimalSize(12, 12), SetFill(0, 1),
						SetDataTip(SPR_FLAG_VEH_STOPPED, STR_VEHICLE_LIST_MASS_STOP_LIST_TOOLTIP),
				NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, GRP_WIDGET_START_ALL), SetMinimalSize(12, 12), SetFill(0, 1),
						SetDataTip(SPR_FLAG_VEH_RUNNING, STR_VEHICLE_LIST_MASS_START_LIST_TOOLTIP),
				NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalSize(0, 12), SetFill(1, 1), SetResize(1, 0), EndContainer(),
				NWidget(WWT_RESIZEBOX, COLOUR_GREY),
			EndContainer(),
		EndContainer(),
	EndContainer(),
};

class VehicleGroupWindow : public BaseVehicleListWindow {
private:
	GroupID group_sel;     ///< Selected group
	VehicleID vehicle_sel; ///< Selected vehicle
	GroupID group_rename;  ///< Group being renamed, INVALID_GROUP if none
	GUIGroupList groups;   ///< List of groups
	uint tiny_step_height; ///< Step height for the group list

	/**
	 * (Re)Build the group list.
	 *
	 * @param owner The owner of the window
	 */
	void BuildGroupList(Owner owner)
	{
		if (!this->groups.NeedRebuild()) return;

		this->groups.Clear();

		const Group *g;
		FOR_ALL_GROUPS(g) {
			if (g->owner == owner && g->vehicle_type == this->vehicle_type) {
				*this->groups.Append() = g;
			}
		}

		this->groups.Compact();
		this->groups.RebuildDone();
	}

	/** Sort the groups by their name */
	static int CDECL GroupNameSorter(const Group * const *a, const Group * const *b)
	{
		static const Group *last_group[2] = { NULL, NULL };
		static char         last_name[2][64] = { "", "" };

		if (*a != last_group[0]) {
			last_group[0] = *a;
			SetDParam(0, (*a)->index);
			GetString(last_name[0], STR_GROUP_NAME, lastof(last_name[0]));
		}

		if (*b != last_group[1]) {
			last_group[1] = *b;
			SetDParam(0, (*b)->index);
			GetString(last_name[1], STR_GROUP_NAME, lastof(last_name[1]));
		}

		int r = strcmp(last_name[0], last_name[1]); // sort by name
		if (r == 0) return (*a)->index - (*b)->index;
		return r;
	}

public:
	VehicleGroupWindow(const WindowDesc *desc, WindowNumber window_number) : BaseVehicleListWindow()
	{
		this->CreateNestedTree(desc);

		this->vehicle_type = (VehicleType)GB(window_number, 11, 5);
		switch (this->vehicle_type) {
			default: NOT_REACHED();
			case VEH_TRAIN:    this->sorting = &_sorting.train;    break;
			case VEH_ROAD:     this->sorting = &_sorting.roadveh;  break;
			case VEH_SHIP:     this->sorting = &_sorting.ship;     break;
			case VEH_AIRCRAFT: this->sorting = &_sorting.aircraft; break;
		}

		this->group_sel = ALL_GROUP;
		this->vehicle_sel = INVALID_VEHICLE;
		this->group_rename = INVALID_GROUP;

		const Owner owner = (Owner)GB(window_number, 0, 8);
		this->vehicles.SetListing(*this->sorting);
		this->vehicles.ForceRebuild();
		this->vehicles.NeedResort();
		this->BuildVehicleList(owner, this->group_sel, IsAllGroupID(this->group_sel) ? VLW_STANDARD : VLW_GROUP_LIST);
		this->SortVehicleList();

		this->groups.ForceRebuild();
		this->groups.NeedResort();
		this->BuildGroupList(owner);
		this->groups.Sort(&GroupNameSorter);

		this->GetWidget<NWidgetCore>(GRP_WIDGET_CAPTION)->widget_data = STR_VEHICLE_LIST_TRAIN_CAPTION + this->vehicle_type;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_LIST_VEHICLE)->tool_tip = STR_VEHICLE_LIST_TRAIN_LIST_TOOLTIP + this->vehicle_type;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_AVAILABLE_VEHICLES)->widget_data = STR_VEHICLE_LIST_AVAILABLE_TRAINS + this->vehicle_type;

		this->GetWidget<NWidgetCore>(GRP_WIDGET_CREATE_GROUP)->widget_data += this->vehicle_type;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_RENAME_GROUP)->widget_data += this->vehicle_type;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_DELETE_GROUP)->widget_data += this->vehicle_type;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_REPLACE_PROTECTION)->widget_data += this->vehicle_type;

		this->FinishInitNested(desc, window_number);
		this->owner = owner;
	}

	~VehicleGroupWindow()
	{
		*this->sorting = this->vehicles.GetListing();
	}

	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
	{
		switch (widget) {
			case GRP_WIDGET_LIST_GROUP:
				this->tiny_step_height = FONT_HEIGHT_NORMAL + WD_MATRIX_TOP;
				resize->height = this->tiny_step_height;
				/* Minimum height is the height of the list widget minus all and default vehicles and a bit for the bottom bar */
				size->height =  4 * GetVehicleListHeight(this->vehicle_type, this->tiny_step_height) - (this->tiny_step_height > 25 ? 2 : 3) * this->tiny_step_height;
				break;

			case GRP_WIDGET_ALL_VEHICLES:
			case GRP_WIDGET_DEFAULT_VEHICLES:
				size->height = FONT_HEIGHT_NORMAL + WD_MATRIX_TOP;
				size->width = max(GetStringBoundingBox(STR_GROUP_DEFAULT_TRAINS + this->vehicle_type).width, GetStringBoundingBox(STR_GROUP_ALL_TRAINS + this->vehicle_type).width);
				size->width += WD_FRAMERECT_LEFT + WD_FRAMERECT_RIGHT + 8 + 8;
				break;

			case GRP_WIDGET_LIST_VEHICLE:
				resize->height = GetVehicleListHeight(this->vehicle_type, FONT_HEIGHT_NORMAL + WD_MATRIX_TOP);
				size->height = 4 * resize->height;
				break;

			case GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN: {
				static const StringID _dropdown_text[] = {STR_VEHICLE_LIST_REPLACE_VEHICLES, STR_VEHICLE_LIST_SEND_FOR_SERVICING, STR_VEHICLE_LIST_SEND_TRAIN_TO_DEPOT, STR_GROUP_ADD_SHARED_VEHICLE, STR_GROUP_REMOVE_ALL_VEHICLES};
				Dimension d = {0, 0};
				for (const StringID *sid = _dropdown_text; sid != endof(_dropdown_text); sid++) {
					d = maxdim(d, GetStringBoundingBox(*sid));
				}
				d.height += padding.height;
				d.width  += padding.width;
				*size = maxdim(*size, d);
			} break;
		}
	}

	virtual void OnInvalidateData(int data)
	{
		if (data == 0) {
			this->vehicles.ForceRebuild();
			this->groups.ForceRebuild();
		} else {
			this->vehicles.ForceResort();
			this->groups.ForceResort();
		}

		if (this->group_rename != INVALID_GROUP && !Group::IsValidID(this->group_rename)) {
			DeleteWindowByClass(WC_QUERY_STRING);
			this->group_rename = INVALID_GROUP;
		}

		if (!(IsAllGroupID(this->group_sel) || IsDefaultGroupID(this->group_sel) || Group::IsValidID(this->group_sel))) {
			this->group_sel = ALL_GROUP;
			HideDropDownMenu(this);
		}
		this->SetDirty();
	}

	virtual void SetStringParameters(int widget) const
	{
		if (widget != GRP_WIDGET_CAPTION) return;

		/* If selected_group == DEFAULT_GROUP || ALL_GROUP, draw the standard caption
		 * We list all vehicles or ungrouped vehicles */
		if (IsDefaultGroupID(this->group_sel) || IsAllGroupID(this->group_sel)) {
			SetDParam(0, STR_COMPANY_NAME);
			SetDParam(1, GB(this->window_number, 0, 8));
			SetDParam(2, this->vehicles.Length());
			SetDParam(3, this->vehicles.Length());
		} else {
			const Group *g = Group::Get(this->group_sel);

			SetDParam(0, STR_GROUP_NAME);
			SetDParam(1, g->index);
			SetDParam(2, g->num_vehicle);
			SetDParam(3, g->num_vehicle);
		}
	}

	virtual void OnPaint()
	{
		const Owner owner = (Owner)GB(this->window_number, 0, 8);

		/* If we select the all vehicles, this->list will contain all vehicles of the owner
		 * else this->list will contain all vehicles which belong to the selected group */
		this->BuildVehicleList(owner, this->group_sel, IsAllGroupID(this->group_sel) ? VLW_STANDARD : VLW_GROUP_LIST);
		this->SortVehicleList();

		this->BuildGroupList(owner);
		this->groups.Sort(&GroupNameSorter);

		this->vscroll2.SetCount(this->groups.Length());
		this->vscroll.SetCount(this->vehicles.Length());

		/* The drop down menu is out, *but* it may not be used, retract it. */
		if (this->vehicles.Length() == 0 && this->IsWidgetLowered(GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN)) {
			this->RaiseWidget(GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN);
			HideDropDownMenu(this);
		}

		/* Disable all lists management button when the list is empty */
		this->SetWidgetsDisabledState(this->vehicles.Length() == 0 || _local_company != owner,
				GRP_WIDGET_STOP_ALL,
				GRP_WIDGET_START_ALL,
				GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN,
				WIDGET_LIST_END);

		/* Disable the group specific function when we select the default group or all vehicles */
		this->SetWidgetsDisabledState(IsDefaultGroupID(this->group_sel) || IsAllGroupID(this->group_sel) || _local_company != owner,
				GRP_WIDGET_DELETE_GROUP,
				GRP_WIDGET_RENAME_GROUP,
				GRP_WIDGET_REPLACE_PROTECTION,
				WIDGET_LIST_END);

		/* Disable remaining buttons for non-local companies
		 * Needed while changing _local_company, eg. by cheats
		 * All procedures (eg. move vehicle to another group)
		 *  verify, whether you are the owner of the vehicle,
		 *  so it doesn't have to be disabled
		 */
		this->SetWidgetsDisabledState(_local_company != owner,
				GRP_WIDGET_CREATE_GROUP,
				GRP_WIDGET_AVAILABLE_VEHICLES,
				WIDGET_LIST_END);

		/* If not a default group and the group has replace protection, show an enabled replace sprite. */
		uint16 protect_sprite = SPR_GROUP_REPLACE_OFF_TRAIN;
		if (!IsDefaultGroupID(this->group_sel) && !IsAllGroupID(this->group_sel) && Group::Get(this->group_sel)->replace_protection) protect_sprite = SPR_GROUP_REPLACE_ON_TRAIN;
		this->GetWidget<NWidgetCore>(GRP_WIDGET_REPLACE_PROTECTION)->widget_data = protect_sprite + this->vehicle_type;

		/* Set text of sort by dropdown */
		this->GetWidget<NWidgetCore>(GRP_WIDGET_SORT_BY_DROPDOWN)->widget_data = this->vehicle_sorter_names[this->vehicles.SortType()];

		this->DrawWidgets();
	}

	virtual void DrawWidget(const Rect &r, int widget) const
	{
		switch (widget) {
			case GRP_WIDGET_ALL_VEHICLES:
				DrawString(r.left + WD_FRAMERECT_LEFT + 8, r.right - WD_FRAMERECT_RIGHT - 8, r.top + WD_MATRIX_TOP,
						STR_GROUP_ALL_TRAINS + this->vehicle_type, IsAllGroupID(this->group_sel) ? TC_WHITE : TC_BLACK);
				break;

			case GRP_WIDGET_DEFAULT_VEHICLES:
				DrawString(r.left + WD_FRAMERECT_LEFT + 8, r.right - WD_FRAMERECT_RIGHT - 8, r.top + WD_MATRIX_TOP,
						STR_GROUP_DEFAULT_TRAINS + this->vehicle_type, IsDefaultGroupID(this->group_sel) ? TC_WHITE : TC_BLACK);
				break;

			case GRP_WIDGET_LIST_GROUP: {
				int y1 = r.top + WD_FRAMERECT_TOP + 1;
				int max = min(this->vscroll2.GetPosition() + this->vscroll2.GetCapacity(), this->groups.Length());
				for (int i = this->vscroll2.GetPosition(); i < max; ++i) {
					const Group *g = this->groups[i];

					assert(g->owner == this->owner);

					/* draw the selected group in white, else we draw it in black */
					SetDParam(0, g->index);
					DrawString(r.left + WD_FRAMERECT_LEFT + 8, r.right - WD_FRAMERECT_RIGHT, y1, STR_GROUP_NAME, (this->group_sel == g->index) ? TC_WHITE : TC_BLACK);

					/* draw the number of vehicles of the group */
					SetDParam(0, g->num_vehicle);
					DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y1 + 1, STR_TINY_COMMA, (this->group_sel == g->index) ? TC_WHITE : TC_BLACK, SA_RIGHT);

					y1 += this->tiny_step_height;
				}
				break;
			}

			case GRP_WIDGET_SORT_BY_ORDER:
				this->DrawSortButtonState(GRP_WIDGET_SORT_BY_ORDER, this->vehicles.IsDescSortOrder() ? SBS_DOWN : SBS_UP);
				break;

			case GRP_WIDGET_LIST_VEHICLE:
				this->DrawVehicleListItems(this->vehicle_sel, this->resize.step_height, r);
				break;
		}
	}

	virtual void OnClick(Point pt, int widget, int click_count)
	{
		switch (widget) {
			case GRP_WIDGET_SORT_BY_ORDER: // Flip sorting method ascending/descending
				this->vehicles.ToggleSortOrder();
				this->SetDirty();
				break;

			case GRP_WIDGET_SORT_BY_DROPDOWN: // Select sorting criteria dropdown menu
				ShowDropDownMenu(this, this->vehicle_sorter_names, this->vehicles.SortType(),  GRP_WIDGET_SORT_BY_DROPDOWN, 0, (this->vehicle_type == VEH_TRAIN || this->vehicle_type == VEH_ROAD) ? 0 : (1 << 10));
				return;

			case GRP_WIDGET_ALL_VEHICLES: // All vehicles button
				if (!IsAllGroupID(this->group_sel)) {
					this->group_sel = ALL_GROUP;
					this->vehicles.ForceRebuild();
					this->SetDirty();
				}
				break;

			case GRP_WIDGET_DEFAULT_VEHICLES: // Ungrouped vehicles button
				if (!IsDefaultGroupID(this->group_sel)) {
					this->group_sel = DEFAULT_GROUP;
					this->vehicles.ForceRebuild();
					this->SetDirty();
				}
				break;

			case GRP_WIDGET_LIST_GROUP: { // Matrix Group
				uint16 id_g = (pt.y - this->GetWidget<NWidgetBase>(GRP_WIDGET_LIST_GROUP)->pos_y) / (int)this->tiny_step_height;

				if (id_g >= this->vscroll2.GetCapacity()) return;

				id_g += this->vscroll2.GetPosition();

				if (id_g >= this->groups.Length()) return;

				this->group_sel = this->groups[id_g]->index;;

				this->vehicles.ForceRebuild();
				this->SetDirty();
				break;
			}

			case GRP_WIDGET_LIST_VEHICLE: { // Matrix Vehicle
				uint32 id_v = (pt.y - this->GetWidget<NWidgetBase>(GRP_WIDGET_LIST_VEHICLE)->pos_y) / (int)this->resize.step_height;
				if (id_v >= this->vscroll.GetCapacity()) return; // click out of bounds

				id_v += this->vscroll.GetPosition();

				if (id_v >= this->vehicles.Length()) return; // click out of list bound

				const Vehicle *v = this->vehicles[id_v];

				this->vehicle_sel = v->index;

				SetObjectToPlaceWnd(v->GetImage(DIR_W), GetVehiclePalette(v), HT_DRAG, this);
				_cursor.vehchain = true;

				this->SetDirty();
				break;
			}

			case GRP_WIDGET_CREATE_GROUP: { // Create a new group
				DoCommandP(0, this->vehicle_type, 0, CMD_CREATE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_CREATE), CcCreateGroup);
				break;
			}

			case GRP_WIDGET_DELETE_GROUP: { // Delete the selected group
				GroupID group = this->group_sel;
				this->group_sel = ALL_GROUP;

				DoCommandP(0, group, 0, CMD_DELETE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_DELETE));
				break;
			}

			case GRP_WIDGET_RENAME_GROUP: // Rename the selected roup
				this->ShowRenameGroupWindow(this->group_sel, false);
				break;

			case GRP_WIDGET_AVAILABLE_VEHICLES:
				ShowBuildVehicleWindow(INVALID_TILE, this->vehicle_type);
				break;

			case GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN:
				ShowGroupActionDropdown(this, this->group_sel);
				break;

			case GRP_WIDGET_START_ALL:
			case GRP_WIDGET_STOP_ALL: { // Start/stop all vehicles of the list
				DoCommandP(0, this->group_sel, ((IsAllGroupID(this->group_sel) ? VLW_STANDARD : VLW_GROUP_LIST) & VLW_MASK)
													| (1 << 6)
													| (widget == GRP_WIDGET_START_ALL ? (1 << 5) : 0)
													| this->vehicle_type, CMD_MASS_START_STOP);

				break;
			}

			case GRP_WIDGET_REPLACE_PROTECTION: {
				const Group *g = Group::GetIfValid(this->group_sel);
				if (g != NULL) {
					DoCommandP(0, this->group_sel, !g->replace_protection, CMD_SET_GROUP_REPLACE_PROTECTION);
				}
				break;
			}
		}
	}

	virtual void OnDragDrop(Point pt, int widget)
	{
		switch (widget) {
			case GRP_WIDGET_ALL_VEHICLES: // All vehicles
			case GRP_WIDGET_DEFAULT_VEHICLES: // Ungrouped vehicles
				DoCommandP(0, DEFAULT_GROUP, this->vehicle_sel, CMD_ADD_VEHICLE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_ADD_VEHICLE));

				this->vehicle_sel = INVALID_VEHICLE;

				this->SetDirty();
				break;

			case GRP_WIDGET_LIST_GROUP: { // Maxtrix group
				uint16 id_g = (pt.y - this->GetWidget<NWidgetBase>(GRP_WIDGET_LIST_GROUP)->pos_y) / (int)this->tiny_step_height;
				const VehicleID vindex = this->vehicle_sel;

				this->vehicle_sel = INVALID_VEHICLE;

				this->SetDirty();

				if (id_g >= this->vscroll2.GetCapacity()) return;

				id_g += this->vscroll2.GetPosition();

				if (id_g >= this->groups.Length()) return;

				DoCommandP(0, this->groups[id_g]->index, vindex, CMD_ADD_VEHICLE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_ADD_VEHICLE));
				break;
			}

			case GRP_WIDGET_LIST_VEHICLE: { // Maxtrix vehicle
				uint32 id_v = (pt.y - this->GetWidget<NWidgetBase>(GRP_WIDGET_LIST_VEHICLE)->pos_y) / (int)this->resize.step_height;
				const VehicleID vindex = this->vehicle_sel;

				this->vehicle_sel = INVALID_VEHICLE;

				this->SetDirty();

				if (id_v >= this->vscroll.GetCapacity()) return; // click out of bounds

				id_v += this->vscroll.GetPosition();

				if (id_v >= this->vehicles.Length()) return; // click out of list bound

				const Vehicle *v = this->vehicles[id_v];
				if (vindex == v->index) {
					ShowVehicleViewWindow(v);
				}
				break;
			}
		}
		_cursor.vehchain = false;
	}

	virtual void OnQueryTextFinished(char *str)
	{
		if (str != NULL) DoCommandP(0, this->group_rename, 0, CMD_RENAME_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_RENAME), NULL, str);
		this->group_rename = INVALID_GROUP;
	}

	virtual void OnResize()
	{
		NWidgetCore *nwi = this->GetWidget<NWidgetCore>(GRP_WIDGET_LIST_GROUP);
		this->vscroll2.SetCapacity(nwi->current_y / this->tiny_step_height);
		nwi->widget_data = (this->vscroll2.GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);

		nwi = this->GetWidget<NWidgetCore>(GRP_WIDGET_LIST_VEHICLE);
		this->vscroll.SetCapacityFromWidget(this, GRP_WIDGET_LIST_VEHICLE);
		nwi->widget_data = (this->vscroll.GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
	}

	virtual void OnDropdownSelect(int widget, int index)
	{
		switch (widget) {
			case GRP_WIDGET_SORT_BY_DROPDOWN:
				this->vehicles.SetSortType(index);
				break;

			case GRP_WIDGET_MANAGE_VEHICLES_DROPDOWN:
				assert(this->vehicles.Length() != 0);

				switch (index) {
					case GALF_REPLACE: // Replace window
						ShowReplaceGroupVehicleWindow(this->group_sel, this->vehicle_type);
						break;
					case GALF_SERVICE: // Send for servicing
						DoCommandP(0, this->group_sel, ((IsAllGroupID(this->group_sel) ? VLW_STANDARD : VLW_GROUP_LIST) & VLW_MASK)
									| DEPOT_MASS_SEND
									| DEPOT_SERVICE, GetCmdSendToDepot(this->vehicle_type));
						break;
					case GALF_DEPOT: // Send to Depots
						DoCommandP(0, this->group_sel, ((IsAllGroupID(this->group_sel) ? VLW_STANDARD : VLW_GROUP_LIST) & VLW_MASK)
									| DEPOT_MASS_SEND, GetCmdSendToDepot(this->vehicle_type));
						break;
					case GALF_ADD_SHARED: // Add shared Vehicles
						assert(Group::IsValidID(this->group_sel));

						DoCommandP(0, this->group_sel, this->vehicle_type, CMD_ADD_SHARED_VEHICLE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_ADD_SHARED_VEHICLE));
						break;
					case GALF_REMOVE_ALL: // Remove all Vehicles from the selected group
						assert(Group::IsValidID(this->group_sel));

						DoCommandP(0, this->group_sel, this->vehicle_type, CMD_REMOVE_ALL_VEHICLES_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_REMOVE_ALL_VEHICLES));
						break;
					default: NOT_REACHED();
				}
				break;

			default: NOT_REACHED();
		}

		this->SetDirty();
	}

	virtual void OnTick()
	{
		if (_pause_mode != PM_UNPAUSED) return;
		if (this->groups.NeedResort() || this->vehicles.NeedResort()) {
			this->SetDirty();
		}
	}

	virtual void OnPlaceObjectAbort()
	{
		/* abort drag & drop */
		this->vehicle_sel = INVALID_VEHICLE;
		this->SetWidgetDirty(GRP_WIDGET_LIST_VEHICLE);
	}

	void ShowRenameGroupWindow(GroupID group, bool empty)
	{
		assert(Group::IsValidID(group));
		this->group_rename = group;
		/* Show empty query for new groups */
		StringID str = STR_EMPTY;
		if (!empty) {
			SetDParam(0, group);
			str = STR_GROUP_NAME;
		}
		ShowQueryString(str, STR_GROUP_RENAME_CAPTION, MAX_LENGTH_GROUP_NAME_BYTES, MAX_LENGTH_GROUP_NAME_PIXELS, this, CS_ALPHANUMERAL, QSF_ENABLE_DEFAULT);
	}

	/**
	 * Tests whether a given vehicle is selected in the window, and unselects it if necessary.
	 * Called when the vehicle is deleted.
	 * @param vehicle Vehicle that is going to be deleted
	 */
	void UnselectVehicle(VehicleID vehicle)
	{
		if (this->vehicle_sel == vehicle) ResetObjectToPlace();
	}
};


static WindowDesc _other_group_desc(
	WDP_AUTO, 460, 246,
	WC_INVALID, WC_NONE,
	WDF_UNCLICK_BUTTONS,
	_nested_group_widgets, lengthof(_nested_group_widgets)
);

const static WindowDesc _train_group_desc(
	WDP_AUTO, 525, 246,
	WC_TRAINS_LIST, WC_NONE,
	WDF_UNCLICK_BUTTONS,
	_nested_group_widgets, lengthof(_nested_group_widgets)
);

void ShowCompanyGroup(CompanyID company, VehicleType vehicle_type)
{
	if (!Company::IsValidID(company)) return;

	WindowNumber num = (vehicle_type << 11) | VLW_GROUP_LIST | company;
	if (vehicle_type == VEH_TRAIN) {
		AllocateWindowDescFront<VehicleGroupWindow>(&_train_group_desc, num);
	} else {
		_other_group_desc.cls = GetWindowClassForVehicleType(vehicle_type);
		AllocateWindowDescFront<VehicleGroupWindow>(&_other_group_desc, num);
	}
}

/**
 * Finds a group list window determined by vehicle type and owner
 * @param vt vehicle type
 * @param owner owner of groups
 * @return pointer to VehicleGroupWindow, NULL if not found
 */
static inline VehicleGroupWindow *FindVehicleGroupWindow(VehicleType vt, Owner owner)
{
	return (VehicleGroupWindow *)FindWindowById(GetWindowClassForVehicleType(vt), (vt << 11) | VLW_GROUP_LIST | owner);
}

/**
 * Opens a 'Rename group' window for newly created group
 * @param success did command succeed?
 * @param tile unused
 * @param p1 vehicle type
 * @param p2 unused
 * @see CmdCreateGroup
 */
void CcCreateGroup(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2)
{
	if (result.Failed()) return;
	assert(p1 <= VEH_AIRCRAFT);

	VehicleGroupWindow *w = FindVehicleGroupWindow((VehicleType)p1, _current_company);
	if (w != NULL) w->ShowRenameGroupWindow(_new_group_id, true);
}

/**
 * Removes the highlight of a vehicle in a group window
 * @param *v Vehicle to remove all highlights from
 */
void DeleteGroupHighlightOfVehicle(const Vehicle *v)
{
	/* If we haven't got any vehicles on the mouse pointer, we haven't got any highlighted in any group windows either
	 * If that is the case, we can skip looping though the windows and save time
	 */
	if (_special_mouse_mode != WSM_DRAGDROP) return;

	VehicleGroupWindow *w = FindVehicleGroupWindow(v->type, v->owner);
	if (w != NULL) w->UnselectVehicle(v->index);
}