Add a method in NewGRFInspectWindow to resolve FeatureIndex

[openttd/fttd.git] / src / newgrf_debug_gui.cpp

/* $Id$ */

/*
 * 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 newgrf_debug_gui.cpp GUIs for debugging NewGRFs. */

#include "stdafx.h"
#include <stdarg.h>
#include "window_gui.h"
#include "window_func.h"
#include "fileio_func.h"
#include "spritecache.h"
#include "string_func.h"
#include "strings_func.h"
#include "textbuf_gui.h"

#include "engine_base.h"
#include "industry.h"
#include "object_base.h"
#include "station_base.h"
#include "town.h"
#include "vehicle_base.h"
#include "map/depot.h"

#include "newgrf_airporttiles.h"
#include "newgrf_debug.h"
#include "newgrf_object.h"
#include "newgrf_spritegroup.h"
#include "newgrf_station.h"
#include "newgrf_town.h"
#include "newgrf_railtype.h"
#include "newgrf_industries.h"
#include "newgrf_industrytiles.h"

#include "widgets/newgrf_debug_widget.h"

#include "table/strings.h"

/** The sprite picker. */
NewGrfDebugSpritePicker _newgrf_debug_sprite_picker = { SPM_NONE, NULL, 0, SmallVector<SpriteID, 256>() };

/**
 * Get the feature index related to the window number.
 * @param window_number The window to get the feature index from.
 * @return the feature index
 */
static inline uint GetFeatureIndex(uint window_number)
{
        return GB(window_number, 0, 24);
}

/**
 * Get the window number for the inspect window given a
 * feature and index.
 * @param feature The feature we want to inspect.
 * @param index   The index/identifier of the feature to inspect.
 * @return the InspectWindow (Window)Number
 */
static inline uint GetInspectWindowNumber(GrfSpecFeature feature, uint index)
{
        assert((index >> 24) == 0);
        return (feature << 24) | index;
}

/**
 * The type of a property to show. This is used to
 * provide an appropriate representation in the GUI.
 */
enum NIType {
        NIT_INT,   ///< The property is a simple integer
        NIT_CARGO, ///< The property is a cargo
};

/** Representation of the data from a NewGRF property. */
struct NIProperty {
        const char *name;       ///< A (human readable) name for the property
        ptrdiff_t offset;       ///< Offset of the variable in the class
        byte read_size;         ///< Number of bytes (i.e. byte, word, dword etc)
        byte prop;              ///< The number of the property
        byte type;
};


/**
 * Representation of the available callbacks with
 * information on when they actually apply.
 */
struct NICallback {
        const char *name; ///< The human readable name of the callback
        ptrdiff_t offset; ///< Offset of the variable in the class
        byte read_size;   ///< The number of bytes (i.e. byte, word, dword etc) to read
        byte cb_bit;      ///< The bit that needs to be set for this callback to be enabled
        uint16 cb_id;     ///< The number of the callback
};
/** Mask to show no bit needs to be enabled for the callback. */
static const int CBM_NO_BIT = UINT8_MAX;

/** Representation on the NewGRF variables. */
struct NIVariable {
        const char *name;
        byte var;
};

/** Helper class to wrap some functionality/queries in. */
class NIHelper {
public:
        /** Silence a warning. */
        virtual ~NIHelper() {}

        /**
         * Is the item with the given index inspectable?
         * @param index the index to check.
         * @return true iff the index is inspectable.
         */
        virtual bool IsInspectable(uint index) const = 0;

        /**
         * Get the parent "window_number" of a given instance.
         * @param index the instance to get the parent for.
         * @return the parent's window_number or UINT32_MAX if there is none.
         */
        virtual uint GetParent(uint index) const = 0;

        /**
         * Get the instance given an index.
         * @param index the index to get the instance for.
         * @return the instance.
         */
        virtual const void *GetInstance(uint index) const = 0;

        /**
         * Get (NewGRF) specs given an index.
         * @param index the index to get the specs for for.
         * @return the specs.
         */
        virtual const void *GetSpec(uint index) const = 0;

        /**
         * Set the string parameters to write the right data for a STRINGn.
         * @param index the index to get the string parameters for.
         */
        virtual void SetStringParameters(uint index) const = 0;

        /**
         * Get the GRFID of the file that includes this item.
         * @param index index to check.
         * @return GRFID of the item. 0 means that the item is not inspectable.
         */
        virtual uint32 GetGRFID(uint index) const = 0;

        /**
         * Resolve (action2) variable for a given index.
         * @param index The (instance) index to resolve the variable for.
         * @param var   The variable to actually resolve.
         * @param param The varaction2 0x60+x parameter to pass.
         * @param avail Return whether the variable is available.
         * @return The resolved variable's value.
         */
        virtual uint Resolve(uint index, uint var, uint param, bool *avail) const = 0;

        /**
         * Used to decide if the PSA needs a parameter or not.
         * @return True iff this item has a PSA that requires a parameter.
         */
        virtual bool PSAWithParameter() const
        {
                return false;
        }

        /**
         * Allows to know the size of the persistent storage.
         * @param index Index of the item.
         * @param grfid Parameter for the PSA. Only required for items with parameters.
         * @return Size of the persistent storage in indices.
         */
        virtual uint GetPSASize(uint index, uint32 grfid) const
        {
                return 0;
        }

        /**
         * Gets the first position of the array containing the persistent storage.
         * @param index Index of the item.
         * @param grfid Parameter for the PSA. Only required for items with parameters.
         * @return Pointer to the first position of the storage array or NULL if not present.
         */
        virtual const int32 *GetPSAFirstPosition(uint index, uint32 grfid) const
        {
                return NULL;
        }

protected:
        /**
         * Helper to make setting the strings easier.
         * @param string the string to actually draw.
         * @param index  the (instance) index for the string.
         */
        void SetSimpleStringParameters(StringID string, uint32 index) const
        {
                SetDParam(0, string);
                SetDParam(1, index);
        }


        /**
         * Helper to make setting the strings easier for objects at a specific tile.
         * @param string the string to draw the object's name
         * @param index  the (instance) index for the string.
         * @param tile   the tile the object is at
         */
        void SetObjectAtStringParameters(StringID string, uint32 index, TileIndex tile) const
        {
                SetDParam(0, STR_NEWGRF_INSPECT_CAPTION_OBJECT_AT);
                SetDParam(1, string);
                SetDParam(2, index);
                SetDParam(3, tile);
        }
};


/** Container for all information for a given feature. */
struct NIFeature {
        const NIProperty *properties; ///< The properties associated with this feature.
        const NICallback *callbacks;  ///< The callbacks associated with this feature.
        const NIVariable *variables;  ///< The variables associated with this feature.
        const NIHelper   *helper;     ///< The class container all helper functions.
};

/* Load all the NewGRF debug data; externalised as it is just a huge bunch of tables. */
#include "table/newgrf_debug_data.h"

/**
 * Get the feature number related to the window number.
 * @param window_number The window to get the feature number for.
 * @return The feature number.
 */
static inline GrfSpecFeature GetFeatureNum(uint window_number)
{
        return (GrfSpecFeature)GB(window_number, 24, 8);
}

/**
 * Get the NIFeature related to the window number.
 * @param window_number The window to get the NIFeature for.
 * @return the NIFeature, or NULL is there isn't one.
 */
static inline const NIFeature *GetFeature(uint window_number)
{
        GrfSpecFeature idx = GetFeatureNum(window_number);
        return idx < GSF_FAKE_END ? _nifeatures[idx] : NULL;
}

/**
 * Get the NIHelper related to the window number.
 * @param window_number The window to get the NIHelper for.
 * @pre GetFeature(window_number) != NULL
 * @return the NIHelper
 */
static inline const NIHelper *GetFeatureHelper(uint window_number)
{
        return GetFeature(window_number)->helper;
}

/** Window used for inspecting NewGRFs. */
struct NewGRFInspectWindow : Window {
        static const int LEFT_OFFSET   = 5; ///< Position of left edge
        static const int RIGHT_OFFSET  = 5; ///< Position of right edge
        static const int TOP_OFFSET    = 5; ///< Position of top edge
        static const int BOTTOM_OFFSET = 5; ///< Position of bottom edge

        /** The value for the variable 60 parameters. */
        static uint32 var60params[GSF_FAKE_END][0x20];

        /** GRFID of the caller of this window, 0 if it has no caller. */
        uint32 caller_grfid;

        /** The currently edited parameter, to update the right one. */
        byte current_edit_param;

        Scrollbar *vscroll;

        /**
         * Check whether the given variable has a parameter.
         * @param variable the variable to check.
         * @return true iff the variable has a parameter.
         */
        static bool HasVariableParameter(uint variable)
        {
                return IsInsideBS(variable, 0x60, 0x20);
        }

        /**
         * Set the GRFID of the item opening this window.
         * @param grfid GRFID of the item opening this window, or 0 if not opened by other window.
         */
        void SetCallerGRFID(uint32 grfid)
        {
                this->caller_grfid = grfid;
                this->SetDirty();
        }

        /**
         * Get the feature index.
         * @return the feature index
         */
        uint GetFeatureIndex() const
        {
                uint index = ::GetFeatureIndex(this->window_number);
                return index;
        }

        NewGRFInspectWindow(WindowDesc *desc, WindowNumber wno) : Window(desc)
        {
                this->CreateNestedTree();
                this->vscroll = this->GetScrollbar(WID_NGRFI_SCROLLBAR);
                this->FinishInitNested(wno);

                this->vscroll->SetCount(0);
                this->SetWidgetDisabledState(WID_NGRFI_PARENT, GetFeatureHelper(this->window_number)->GetParent(this->GetFeatureIndex()) == UINT32_MAX);
        }

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

                GetFeatureHelper(this->window_number)->SetStringParameters(this->GetFeatureIndex());
        }

        virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
        {
                if (widget != WID_NGRFI_MAINPANEL) return;

                resize->height = max(11, FONT_HEIGHT_NORMAL + 1);
                resize->width  = 1;

                size->height = 5 * resize->height + TOP_OFFSET + BOTTOM_OFFSET;
        }

        /**
         * Helper function to draw a string (line) in the window.
         * @param r      The (screen) rectangle we must draw within
         * @param offset The offset (in lines) we want to draw for
         * @param format The format string
         */
        void WARN_FORMAT(4, 5) DrawString(const Rect &r, int offset, const char *format, ...) const
        {
                char buf[1024];

                va_list va;
                va_start(va, format);
                vsnprintf(buf, lengthof(buf), format, va);
                va_end(va);

                offset -= this->vscroll->GetPosition();
                if (offset < 0 || offset >= this->vscroll->GetCapacity()) return;

                ::DrawString(r.left + LEFT_OFFSET, r.right - RIGHT_OFFSET, r.top + TOP_OFFSET + (offset * this->resize.step_height), buf, TC_BLACK);
        }

        virtual void DrawWidget(const Rect &r, int widget) const
        {
                if (widget != WID_NGRFI_MAINPANEL) return;

                uint index = this->GetFeatureIndex();
                const NIFeature *nif  = GetFeature(this->window_number);
                const NIHelper *nih   = nif->helper;
                const void *base      = nih->GetInstance(index);
                const void *base_spec = nih->GetSpec(index);

                uint i = 0;
                if (nif->variables != NULL) {
                        this->DrawString(r, i++, "Variables:");
                        for (const NIVariable *niv = nif->variables; niv->name != NULL; niv++) {
                                bool avail = true;
                                uint param = HasVariableParameter(niv->var) ? NewGRFInspectWindow::var60params[GetFeatureNum(this->window_number)][niv->var - 0x60] : 0;
                                uint value = nih->Resolve(index, niv->var, param, &avail);

                                if (!avail) continue;

                                if (HasVariableParameter(niv->var)) {
                                        this->DrawString(r, i++, "  %02x[%02x]: %08x (%s)", niv->var, param, value, niv->name);
                                } else {
                                        this->DrawString(r, i++, "  %02x: %08x (%s)", niv->var, value, niv->name);
                                }
                        }
                }

                uint psa_size = nih->GetPSASize(index, this->caller_grfid);
                const int32 *psa = nih->GetPSAFirstPosition(index, this->caller_grfid);
                if (psa_size != 0 && psa != NULL) {
                        if (nih->PSAWithParameter()) {
                                this->DrawString(r, i++, "Persistent storage [%08X]:", BSWAP32(this->caller_grfid));
                        } else {
                                this->DrawString(r, i++, "Persistent storage:");
                        }
                        assert(psa_size % 4 == 0);
                        for (uint j = 0; j < psa_size; j += 4, psa += 4) {
                                this->DrawString(r, i++, "  %i: %i %i %i %i", j, psa[0], psa[1], psa[2], psa[3]);
                        }
                }

                if (nif->properties != NULL) {
                        this->DrawString(r, i++, "Properties:");
                        for (const NIProperty *nip = nif->properties; nip->name != NULL; nip++) {
                                const void *ptr = (const byte *)base + nip->offset;
                                uint value;
                                switch (nip->read_size) {
                                        case 1: value = *(const uint8  *)ptr; break;
                                        case 2: value = *(const uint16 *)ptr; break;
                                        case 4: value = *(const uint32 *)ptr; break;
                                        default: NOT_REACHED();
                                }

                                StringID string;
                                SetDParam(0, value);
                                switch (nip->type) {
                                        case NIT_INT:
                                                string = STR_JUST_INT;
                                                break;

                                        case NIT_CARGO:
                                                string = value != INVALID_CARGO ? CargoSpec::Get(value)->name : STR_QUANTITY_N_A;
                                                break;

                                        default:
                                                NOT_REACHED();
                                }

                                char buffer[64];
                                GetString(buffer, string, lastof(buffer));
                                this->DrawString(r, i++, "  %02x: %s (%s)", nip->prop, buffer, nip->name);
                        }
                }

                if (nif->callbacks != NULL) {
                        this->DrawString(r, i++, "Callbacks:");
                        for (const NICallback *nic = nif->callbacks; nic->name != NULL; nic++) {
                                if (nic->cb_bit != CBM_NO_BIT) {
                                        const void *ptr = (const byte *)base_spec + nic->offset;
                                        uint value;
                                        switch (nic->read_size) {
                                                case 1: value = *(const uint8  *)ptr; break;
                                                case 2: value = *(const uint16 *)ptr; break;
                                                case 4: value = *(const uint32 *)ptr; break;
                                                default: NOT_REACHED();
                                        }

                                        if (!HasBit(value, nic->cb_bit)) continue;
                                        this->DrawString(r, i++, "  %03x: %s", nic->cb_id, nic->name);
                                } else {
                                        this->DrawString(r, i++, "  %03x: %s (unmasked)", nic->cb_id, nic->name);
                                }
                        }
                }

                /* Not nice and certainly a hack, but it beats duplicating
                 * this whole function just to count the actual number of
                 * elements. Especially because they need to be redrawn. */
                const_cast<NewGRFInspectWindow*>(this)->vscroll->SetCount(i);
        }

        virtual void OnClick(Point pt, int widget, int click_count)
        {
                switch (widget) {
                        case WID_NGRFI_PARENT: {
                                const NIHelper *nih   = GetFeatureHelper(this->window_number);
                                uint index = nih->GetParent(this->GetFeatureIndex());
                                ::ShowNewGRFInspectWindow((GrfSpecFeature)GB(index, 24, 8), ::GetFeatureIndex(index), nih->GetGRFID(this->GetFeatureIndex()));
                                break;
                        }

                        case WID_NGRFI_MAINPANEL: {
                                /* Does this feature have variables? */
                                const NIFeature *nif  = GetFeature(this->window_number);
                                if (nif->variables == NULL) return;

                                /* Get the line, make sure it's within the boundaries. */
                                int line = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_NGRFI_MAINPANEL, TOP_OFFSET);
                                if (line == INT_MAX) return;

                                /* Find the variable related to the line */
                                for (const NIVariable *niv = nif->variables; niv->name != NULL; niv++, line--) {
                                        if (line != 1) continue; // 1 because of the "Variables:" line

                                        if (!HasVariableParameter(niv->var)) break;

                                        this->current_edit_param = niv->var;
                                        ShowQueryString(STR_EMPTY, STR_NEWGRF_INSPECT_QUERY_CAPTION, 9, this, CS_HEXADECIMAL, QSF_NONE);
                                }
                        }
                }
        }

        virtual void OnQueryTextFinished(char *str)
        {
                if (StrEmpty(str)) return;

                NewGRFInspectWindow::var60params[GetFeatureNum(this->window_number)][this->current_edit_param - 0x60] = strtol(str, NULL, 16);
                this->SetDirty();
        }

        virtual void OnResize()
        {
                this->vscroll->SetCapacityFromWidget(this, WID_NGRFI_MAINPANEL, TOP_OFFSET + BOTTOM_OFFSET);
        }
};

/* static */ uint32 NewGRFInspectWindow::var60params[GSF_FAKE_END][0x20] = { {0} }; // Use spec to have 0s in whole array

static const NWidgetPart _nested_newgrf_inspect_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_GREY),
                NWidget(WWT_CAPTION, COLOUR_GREY, WID_NGRFI_CAPTION), SetDataTip(STR_NEWGRF_INSPECT_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_NGRFI_PARENT), SetDataTip(STR_NEWGRF_INSPECT_PARENT_BUTTON, STR_NEWGRF_INSPECT_PARENT_TOOLTIP),
                NWidget(WWT_SHADEBOX, COLOUR_GREY),
                NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
                NWidget(WWT_STICKYBOX, COLOUR_GREY),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PANEL, COLOUR_GREY, WID_NGRFI_MAINPANEL), SetMinimalSize(300, 0), SetScrollbar(WID_NGRFI_SCROLLBAR), EndContainer(),
                NWidget(NWID_VERTICAL),
                        NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_NGRFI_SCROLLBAR),
                        NWidget(WWT_RESIZEBOX, COLOUR_GREY),
                EndContainer(),
        EndContainer(),
};

static WindowDesc _newgrf_inspect_desc(
        WDP_AUTO, "newgrf_inspect", 400, 300,
        WC_NEWGRF_INSPECT, WC_NONE,
        0,
        _nested_newgrf_inspect_widgets, lengthof(_nested_newgrf_inspect_widgets)
);

/**
 * Show the inspect window for a given feature and index.
 * The index is normally an in-game location/identifier, such
 * as a TileIndex or an IndustryID depending on the feature
 * we want to inspect.
 * @param feature The feature we want to inspect.
 * @param index   The index/identifier of the feature to inspect.
 * @param grfid   GRFID of the item opening this window, or 0 if not opened by other window.
 */
void ShowNewGRFInspectWindow(GrfSpecFeature feature, uint index, const uint32 grfid)
{
        if (!IsNewGRFInspectable(feature, index)) return;

        WindowNumber wno = GetInspectWindowNumber(feature, index);
        NewGRFInspectWindow *w = AllocateWindowDescFront<NewGRFInspectWindow>(&_newgrf_inspect_desc, wno);
        if (w == NULL) w = (NewGRFInspectWindow *)FindWindowById(WC_NEWGRF_INSPECT, wno);
        w->SetCallerGRFID(grfid);
}

/**
 * Delete inspect window for a given feature and index.
 * The index is normally an in-game location/identifier, such
 * as a TileIndex or an IndustryID depending on the feature
 * we want to inspect.
 * @param feature The feature we want to delete the window for.
 * @param index   The index/identifier of the feature to delete.
 */
void DeleteNewGRFInspectWindow(GrfSpecFeature feature, uint index)
{
        if (feature == GSF_INVALID) return;

        WindowNumber wno = GetInspectWindowNumber(feature, index);
        DeleteWindowById(WC_NEWGRF_INSPECT, wno);

        /* Reinitialise the land information window to remove the "debug" sprite if needed.
         * Note: Since we might be called from a command here, it is important to not execute
         * the invalidation immediately. The landinfo window tests commands itself. */
        InvalidateWindowData(WC_LAND_INFO, 0, 1);
}

/**
 * Can we inspect the data given a certain feature and index.
 * The index is normally an in-game location/identifier, such
 * as a TileIndex or an IndustryID depending on the feature
 * we want to inspect.
 * @param feature The feature we want to inspect.
 * @param index   The index/identifier of the feature to inspect.
 * @return true if there is something to show.
 */
bool IsNewGRFInspectable(GrfSpecFeature feature, uint index)
{
        const NIFeature *nif = GetFeature(GetInspectWindowNumber(feature, index));
        if (nif == NULL) return false;
        return nif->helper->IsInspectable(index);
}

/**
 * Get the GrfSpecFeature associated with the tile.
 * @param tile The tile to get the feature from.
 * @return the GrfSpecFeature.
 */
GrfSpecFeature GetGrfSpecFeature(TileIndex tile)
{
        if (IsHouseTile(tile)) {
                return GSF_HOUSES;
        } else if (IsIndustryTile(tile)) {
                return GSF_INDUSTRYTILES;
        }

        switch (GetTileType(tile)) {
                default:              return GSF_INVALID;
                case TT_RAILWAY:      return IsTileSubtype(tile, TT_TRACK) ? GSF_RAILTYPES : GSF_INVALID;
                case TT_MISC:         return (IsRailDepotTile(tile) || IsLevelCrossingTile(tile)) ? GSF_RAILTYPES : GSF_INVALID;
                case TT_OBJECT:       return GSF_OBJECTS;

                case TT_STATION:
                        switch (GetStationType(tile)) {
                                case STATION_RAIL:    return GSF_STATIONS;
                                case STATION_AIRPORT: return GSF_AIRPORTTILES;
                                default:              return GSF_INVALID;
                        }
        }
}

/**
 * Get the GrfSpecFeature associated with the vehicle.
 * @param type The vehicle type to get the feature from.
 * @return the GrfSpecFeature.
 */
GrfSpecFeature GetGrfSpecFeature(VehicleType type)
{
        switch (type) {
                case VEH_TRAIN:    return GSF_TRAINS;
                case VEH_ROAD:     return GSF_ROADVEHICLES;
                case VEH_SHIP:     return GSF_SHIPS;
                case VEH_AIRCRAFT: return GSF_AIRCRAFT;
                default:           return GSF_INVALID;
        }
}



/**** Sprite Aligner ****/

/** Window used for aligning sprites. */
struct SpriteAlignerWindow : Window {
        SpriteID current_sprite; ///< The currently shown sprite
        Scrollbar *vscroll;

        SpriteAlignerWindow(WindowDesc *desc, WindowNumber wno) : Window(desc)
        {
                this->CreateNestedTree();
                this->vscroll = this->GetScrollbar(WID_SA_SCROLLBAR);
                this->FinishInitNested(wno);

                /* Oh yes, we assume there is at least one normal sprite! */
                while (GetSpriteType(this->current_sprite) != ST_NORMAL) this->current_sprite++;
        }

        virtual void SetStringParameters(int widget) const
        {
                switch (widget) {
                        case WID_SA_CAPTION:
                                SetDParam(0, this->current_sprite);
                                SetDParamStr(1, FioGetFilename(GetOriginFileSlot(this->current_sprite)));
                                break;

                        case WID_SA_OFFSETS: {
                                const Sprite *spr = GetSprite(this->current_sprite, ST_NORMAL);
                                SetDParam(0, spr->x_offs / ZOOM_LVL_BASE);
                                SetDParam(1, spr->y_offs / ZOOM_LVL_BASE);
                                break;
                        }

                        default:
                                break;
                }
        }

        virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
        {
                if (widget != WID_SA_LIST) return;

                resize->height = max(11, FONT_HEIGHT_NORMAL + 1);
                resize->width  = 1;

                /* Resize to about 200 pixels (for the preview) */
                size->height = (1 + 200 / resize->height) * resize->height;
        }

        virtual void DrawWidget(const Rect &r, int widget) const
        {
                switch (widget) {
                        case WID_SA_SPRITE: {
                                /* Center the sprite ourselves */
                                const Sprite *spr = GetSprite(this->current_sprite, ST_NORMAL);
                                int width  = r.right  - r.left + 1;
                                int height = r.bottom - r.top  + 1;
                                int x = r.left - spr->x_offs / ZOOM_LVL_BASE + (width  - spr->width / ZOOM_LVL_BASE) / 2;
                                int y = r.top  - spr->y_offs / ZOOM_LVL_BASE + (height - spr->height / ZOOM_LVL_BASE) / 2;

                                /* And draw only the part within the sprite area */
                                SubSprite subspr = {
                                        spr->x_offs + (spr->width  - width  * ZOOM_LVL_BASE) / 2 + 1,
                                        spr->y_offs + (spr->height - height * ZOOM_LVL_BASE) / 2 + 1,
                                        spr->x_offs + (spr->width  + width  * ZOOM_LVL_BASE) / 2 - 1,
                                        spr->y_offs + (spr->height + height * ZOOM_LVL_BASE) / 2 - 1,
                                };

                                DrawSprite(this->current_sprite, PAL_NONE, x, y, &subspr, ZOOM_LVL_GUI);
                                break;
                        }

                        case WID_SA_LIST: {
                                const NWidgetBase *nwid = this->GetWidget<NWidgetBase>(widget);
                                int step_size = nwid->resize_y;

                                SmallVector<SpriteID, 256> &list = _newgrf_debug_sprite_picker.sprites;
                                int max = min<int>(this->vscroll->GetPosition() + this->vscroll->GetCapacity(), list.Length());

                                int y = r.top + WD_FRAMERECT_TOP;
                                for (int i = this->vscroll->GetPosition(); i < max; i++) {
                                        SetDParam(0, list[i]);
                                        DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, STR_BLACK_COMMA, TC_FROMSTRING, SA_RIGHT | SA_FORCE);
                                        y += step_size;
                                }
                                break;
                        }
                }
        }

        virtual void OnClick(Point pt, int widget, int click_count)
        {
                switch (widget) {
                        case WID_SA_PREVIOUS:
                                do {
                                        this->current_sprite = (this->current_sprite == 0 ? GetMaxSpriteID() :  this->current_sprite) - 1;
                                } while (GetSpriteType(this->current_sprite) != ST_NORMAL);
                                this->SetDirty();
                                break;

                        case WID_SA_GOTO:
                                ShowQueryString(STR_EMPTY, STR_SPRITE_ALIGNER_GOTO_CAPTION, 7, this, CS_NUMERAL, QSF_NONE);
                                break;

                        case WID_SA_NEXT:
                                do {
                                        this->current_sprite = (this->current_sprite + 1) % GetMaxSpriteID();
                                } while (GetSpriteType(this->current_sprite) != ST_NORMAL);
                                this->SetDirty();
                                break;

                        case WID_SA_PICKER:
                                this->LowerWidget(WID_SA_PICKER);
                                _newgrf_debug_sprite_picker.mode = SPM_WAIT_CLICK;
                                this->SetDirty();
                                break;

                        case WID_SA_LIST: {
                                const NWidgetBase *nwid = this->GetWidget<NWidgetBase>(widget);
                                int step_size = nwid->resize_y;

                                uint i = this->vscroll->GetPosition() + (pt.y - nwid->pos_y) / step_size;
                                if (i < _newgrf_debug_sprite_picker.sprites.Length()) {
                                        SpriteID spr = _newgrf_debug_sprite_picker.sprites[i];
                                        if (GetSpriteType(spr) == ST_NORMAL) this->current_sprite = spr;
                                }
                                this->SetDirty();
                                break;
                        }

                        case WID_SA_UP:
                        case WID_SA_DOWN:
                        case WID_SA_LEFT:
                        case WID_SA_RIGHT: {
                                /*
                                 * Yes... this is a hack.
                                 *
                                 * No... I don't think it is useful to make this less of a hack.
                                 *
                                 * If you want to align sprites, you just need the number. Generally
                                 * the sprite caches are big enough to not remove the sprite from the
                                 * cache. If that's not the case, just let the NewGRF developer
                                 * increase the cache size instead of storing thousands of offsets
                                 * for the incredibly small chance that it's actually going to be
                                 * used by someone and the sprite cache isn't big enough for that
                                 * particular NewGRF developer.
                                 */
                                Sprite *spr = const_cast<Sprite *>(GetSprite(this->current_sprite, ST_NORMAL));
                                switch (widget) {
                                        case WID_SA_UP:    spr->y_offs -= ZOOM_LVL_BASE; break;
                                        case WID_SA_DOWN:  spr->y_offs += ZOOM_LVL_BASE; break;
                                        case WID_SA_LEFT:  spr->x_offs -= ZOOM_LVL_BASE; break;
                                        case WID_SA_RIGHT: spr->x_offs += ZOOM_LVL_BASE; break;
                                }
                                /* Of course, we need to redraw the sprite, but where is it used?
                                 * Everywhere is a safe bet. */
                                MarkWholeScreenDirty();
                                break;
                        }
                }
        }

        virtual void OnQueryTextFinished(char *str)
        {
                if (StrEmpty(str)) return;

                this->current_sprite = atoi(str);
                if (this->current_sprite >= GetMaxSpriteID()) this->current_sprite = 0;
                while (GetSpriteType(this->current_sprite) != ST_NORMAL) {
                        this->current_sprite = (this->current_sprite + 1) % GetMaxSpriteID();
                }
                this->SetDirty();
        }

        /**
         * Some data on this window has become invalid.
         * @param data Information about the changed data.
         * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
         */
        virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
        {
                if (!gui_scope) return;
                if (data == 1) {
                        /* Sprite picker finished */
                        this->RaiseWidget(WID_SA_PICKER);
                        this->vscroll->SetCount(_newgrf_debug_sprite_picker.sprites.Length());
                }
        }

        virtual void OnResize()
        {
                this->vscroll->SetCapacityFromWidget(this, WID_SA_LIST);
        }
};

static const NWidgetPart _nested_sprite_aligner_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_GREY),
                NWidget(WWT_CAPTION, COLOUR_GREY, WID_SA_CAPTION), SetDataTip(STR_SPRITE_ALIGNER_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_SHADEBOX, COLOUR_GREY),
                NWidget(WWT_STICKYBOX, COLOUR_GREY),
        EndContainer(),
        NWidget(WWT_PANEL, COLOUR_GREY),
                NWidget(NWID_HORIZONTAL), SetPIP(0, 0, 10),
                        NWidget(NWID_VERTICAL), SetPIP(10, 5, 10),
                                NWidget(NWID_HORIZONTAL, NC_EQUALSIZE), SetPIP(10, 5, 10),
                                        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SA_PREVIOUS), SetDataTip(STR_SPRITE_ALIGNER_PREVIOUS_BUTTON, STR_SPRITE_ALIGNER_PREVIOUS_TOOLTIP), SetFill(1, 0),
                                        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SA_GOTO), SetDataTip(STR_SPRITE_ALIGNER_GOTO_BUTTON, STR_SPRITE_ALIGNER_GOTO_TOOLTIP), SetFill(1, 0),
                                        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SA_NEXT), SetDataTip(STR_SPRITE_ALIGNER_NEXT_BUTTON, STR_SPRITE_ALIGNER_NEXT_TOOLTIP), SetFill(1, 0),
                                EndContainer(),
                                NWidget(NWID_HORIZONTAL), SetPIP(10, 5, 10),
                                        NWidget(NWID_SPACER), SetFill(1, 1),
                                        NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SA_UP), SetDataTip(SPR_ARROW_UP, STR_SPRITE_ALIGNER_MOVE_TOOLTIP), SetResize(0, 0),
                                        NWidget(NWID_SPACER), SetFill(1, 1),
                                EndContainer(),
                                NWidget(NWID_HORIZONTAL_LTR), SetPIP(10, 5, 10),
                                        NWidget(NWID_VERTICAL),
                                                NWidget(NWID_SPACER), SetFill(1, 1),
                                                NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SA_LEFT), SetDataTip(SPR_ARROW_LEFT, STR_SPRITE_ALIGNER_MOVE_TOOLTIP), SetResize(0, 0),
                                                NWidget(NWID_SPACER), SetFill(1, 1),
                                        EndContainer(),
                                        NWidget(WWT_PANEL, COLOUR_DARK_BLUE, WID_SA_SPRITE), SetDataTip(STR_NULL, STR_SPRITE_ALIGNER_SPRITE_TOOLTIP),
                                        EndContainer(),
                                        NWidget(NWID_VERTICAL),
                                                NWidget(NWID_SPACER), SetFill(1, 1),
                                                NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SA_RIGHT), SetDataTip(SPR_ARROW_RIGHT, STR_SPRITE_ALIGNER_MOVE_TOOLTIP), SetResize(0, 0),
                                                NWidget(NWID_SPACER), SetFill(1, 1),
                                        EndContainer(),
                                EndContainer(),
                                NWidget(NWID_HORIZONTAL), SetPIP(10, 5, 10),
                                        NWidget(NWID_SPACER), SetFill(1, 1),
                                        NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SA_DOWN), SetDataTip(SPR_ARROW_DOWN, STR_SPRITE_ALIGNER_MOVE_TOOLTIP), SetResize(0, 0),
                                        NWidget(NWID_SPACER), SetFill(1, 1),
                                EndContainer(),
                                NWidget(NWID_HORIZONTAL), SetPIP(10, 5, 10),
                                        NWidget(WWT_LABEL, COLOUR_GREY, WID_SA_OFFSETS), SetDataTip(STR_SPRITE_ALIGNER_OFFSETS, STR_NULL), SetFill(1, 0),
                                EndContainer(),
                        EndContainer(),
                        NWidget(NWID_VERTICAL), SetPIP(10, 5, 10),
                                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_SA_PICKER), SetDataTip(STR_SPRITE_ALIGNER_PICKER_BUTTON, STR_SPRITE_ALIGNER_PICKER_TOOLTIP), SetFill(1, 0),
                                NWidget(NWID_HORIZONTAL),
                                        NWidget(WWT_MATRIX, COLOUR_GREY, WID_SA_LIST), SetResize(1, 1), SetMatrixDataTip(1, 0, STR_NULL), SetFill(1, 1), SetScrollbar(WID_SA_SCROLLBAR),
                                        NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_SA_SCROLLBAR),
                                EndContainer(),
                        EndContainer(),
                EndContainer(),
        EndContainer(),
};

static WindowDesc _sprite_aligner_desc(
        WDP_AUTO, "sprite_aligner", 400, 300,
        WC_SPRITE_ALIGNER, WC_NONE,
        0,
        _nested_sprite_aligner_widgets, lengthof(_nested_sprite_aligner_widgets)
);

/**
 * Show the window for aligning sprites.
 */
void ShowSpriteAlignerWindow()
{
        AllocateWindowDescFront<SpriteAlignerWindow>(&_sprite_aligner_desc, 0);
}