#pragma region Copyright (c) 2014-2017 OpenRCT2 Developers
/*****************************************************************************
 * OpenRCT2, an open source clone of Roller Coaster Tycoon 2.
 *
 * OpenRCT2 is the work of many authors, a full list can be found in contributors.md
 * For more information, visit https://github.com/OpenRCT2/OpenRCT2
 *
 * OpenRCT2 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, either version 3 of the License, or
 * (at your option) any later version.
 *
 * A full copy of the GNU General Public License can be found in licence.txt
 *****************************************************************************/
#pragma endregion

#include <openrct2/interface/Cursors.h>
#include <openrct2/object/ObjectManager.h>
#include <openrct2/object/ObjectRepository.h>
#include <openrct2/OpenRCT2.h>
#include <openrct2/core/Util.hpp>
#include <openrct2-ui/windows/Window.h>

#include <openrct2/Editor.h>
#include <openrct2/input.h>
#include <openrct2/interface/widget.h>
#include <openrct2/localisation/localisation.h>
#include <openrct2/management/Research.h>
#include <openrct2/sprites.h>
#include <openrct2/util/util.h>
#include <openrct2/world/scenery.h>
#include <openrct2/windows/_legacy.h>

#pragma region Widgets

enum {
    WIDX_BACKGROUND,
    WIDX_TITLE,
    WIDX_CLOSE,
    WIDX_PAGE_BACKGROUND,
    WIDX_TAB_1,
    WIDX_PRE_RESEARCHED_SCROLL,
    WIDX_RESEARCH_ORDER_SCROLL,
    WIDX_PREVIEW,
    WIDX_RANDOM_SHUFFLE,
    WIDX_MOVE_ITEMS_TO_BOTTOM,
    WIDX_MOVE_ITEMS_TO_TOP
};

static rct_widget window_editor_inventions_list_widgets[] = {
    { WWT_FRAME,            0,  0,      599,    0,      399,    STR_NONE,               STR_NONE                },
    { WWT_CAPTION,          0,  1,      598,    1,      14,     STR_INVENTION_LIST,     STR_WINDOW_TITLE_TIP    },
    { WWT_CLOSEBOX,         0,  587,    597,    2,      13,     STR_CLOSE_X,            STR_CLOSE_WINDOW_TIP    },
    { WWT_RESIZE,           1,  0,      599,    43,     399,    STR_NONE,               STR_NONE                },
    { WWT_TAB,              1,  3,      33,     17,     43,     IMAGE_TYPE_REMAP | SPR_TAB,   STR_NONE                },
    { WWT_SCROLL,           1,  4,      371,    56,     175,    SCROLL_VERTICAL,        STR_NONE                },
    { WWT_SCROLL,           1,  4,      371,    189,    396,    SCROLL_VERTICAL,        STR_NONE                },
    { WWT_FLATBTN,          1,  431,    544,    106,    219,    0xFFFFFFFF,             STR_NONE                },
    { WWT_DROPDOWN_BUTTON,  1,  375,    594,    383,    396,    STR_RANDOM_SHUFFLE,     STR_RANDOM_SHUFFLE_TIP  },
    { WWT_DROPDOWN_BUTTON,  1,  375,    594,    368,    381,    STR_MOVE_ALL_BOTTOM,    STR_NONE                },
    { WWT_DROPDOWN_BUTTON,  1,  375,    594,    353,    366,    STR_MOVE_ALL_TOP,       STR_NONE                },
    { WIDGETS_END }
};

static rct_widget window_editor_inventions_list_drag_widgets[] = {
    { WWT_IMGBTN,           0,  0,      149,    0,      13,     STR_NONE,               STR_NONE                },
    { WIDGETS_END }
};

#pragma endregion

#pragma region Events

static void window_editor_inventions_list_close(rct_window *w);
static void window_editor_inventions_list_mouseup(rct_window *w, rct_widgetindex widgetIndex);
static void window_editor_inventions_list_update(rct_window *w);
static void window_editor_inventions_list_scrollgetheight(rct_window *w, sint32 scrollIndex, sint32 *width, sint32 *height);
static void window_editor_inventions_list_scrollmousedown(rct_window *w, sint32 scrollIndex, sint32 x, sint32 y);
static void window_editor_inventions_list_scrollmouseover(rct_window *w, sint32 scrollIndex, sint32 x, sint32 y);
static void window_editor_inventions_list_tooltip(rct_window* w, rct_widgetindex widgetIndex, rct_string_id *stringId);
static void window_editor_inventions_list_cursor(rct_window *w, rct_widgetindex widgetIndex, sint32 x, sint32 y, sint32 *cursorId);
static void window_editor_inventions_list_invalidate(rct_window *w);
static void window_editor_inventions_list_paint(rct_window *w, rct_drawpixelinfo *dpi);
static void window_editor_inventions_list_scrollpaint(rct_window *w, rct_drawpixelinfo *dpi, sint32 scrollIndex);

static void window_editor_inventions_list_drag_cursor(rct_window *w, rct_widgetindex widgetIndex, sint32 x, sint32 y, sint32 *cursorId);
static void window_editor_inventions_list_drag_moved(rct_window* w, sint32 x, sint32 y);
static void window_editor_inventions_list_drag_paint(rct_window *w, rct_drawpixelinfo *dpi);

// 0x0098177C
static rct_window_event_list window_editor_inventions_list_events = {
    window_editor_inventions_list_close,
    window_editor_inventions_list_mouseup,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    window_editor_inventions_list_update,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    window_editor_inventions_list_scrollgetheight,
    window_editor_inventions_list_scrollmousedown,
    nullptr,
    window_editor_inventions_list_scrollmouseover,
    nullptr,
    nullptr,
    nullptr,
    window_editor_inventions_list_tooltip,
    window_editor_inventions_list_cursor,
    nullptr,
    window_editor_inventions_list_invalidate,
    window_editor_inventions_list_paint,
    window_editor_inventions_list_scrollpaint
};

// 0x009817EC
static rct_window_event_list window_editor_inventions_list_drag_events = {
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    nullptr,
    window_editor_inventions_list_drag_cursor,
    window_editor_inventions_list_drag_moved,
    nullptr,
    window_editor_inventions_list_drag_paint,
    nullptr
};

#pragma endregion

static rct_research_item *_editorInventionsListDraggedItem;

static const rct_string_id EditorInventionsResearchCategories[] = {
    STR_RESEARCH_NEW_TRANSPORT_RIDES,
    STR_RESEARCH_NEW_GENTLE_RIDES,
    STR_RESEARCH_NEW_ROLLER_COASTERS,
    STR_RESEARCH_NEW_THRILL_RIDES,
    STR_RESEARCH_NEW_WATER_RIDES,
    STR_RESEARCH_NEW_SHOPS_AND_STALLS,
    STR_RESEARCH_NEW_SCENERY_AND_THEMING,
};

static void window_editor_inventions_list_drag_open(rct_research_item *researchItem);
static void move_research_item(rct_research_item *beforeItem);

static sint32 research_item_is_always_researched(rct_research_item *researchItem)
{
    return (researchItem->entryIndex & (RESEARCH_ENTRY_FLAG_RIDE_ALWAYS_RESEARCHED | RESEARCH_ENTRY_FLAG_SCENERY_SET_ALWAYS_RESEARCHED)) != 0;
}

/**
 *
 *  rct2: 0x0068596F
 * Sets rides that are in use to be always researched
 */
static void research_rides_setup(){
    // Reset all objects to not required
    for (uint8 object_type = OBJECT_TYPE_RIDE; object_type < OBJECT_TYPE_COUNT; object_type++){
        uint8* in_use = Editor::SelectedObjects[object_type];
        for (uint8 num_objects = object_entry_group_counts[object_type]; num_objects != 0; num_objects--){
            *in_use++ = OBJECT_SELECTION_NOT_SELECTED_OR_REQUIRED;
        }
    }

    // Set research required for rides in use
    for (uint16 rideIndex = 0; rideIndex < 255; rideIndex++){
        Ride * ride = get_ride(rideIndex);
        if (ride->type == RIDE_TYPE_NULL)continue;
        Editor::SelectedObjects[OBJECT_TYPE_RIDE][ride->subtype] |= OBJECT_SELECTION_FLAG_SELECTED;
    }

    for (rct_research_item* research = gResearchItems; research->entryIndex != RESEARCHED_ITEMS_END; research++)
    {
        if (research->entryIndex & RESEARCH_ENTRY_FLAG_RIDE_ALWAYS_RESEARCHED)
            continue;

        // If not a ride
        if ((research->entryIndex & 0xFFFFFF) < 0x10000)
            continue;

        uint8 ride_base_type = research_get_ride_base_type(research->entryIndex);

        uint8 object_index = research->entryIndex & 0xFF;
        rct_ride_entry* ride_entry = get_ride_entry(object_index);

        bool master_found = false;
        if (!(ride_entry->flags & RIDE_ENTRY_FLAG_SEPARATE_RIDE))
        {
            for (uint8 rideType = 0; rideType < object_entry_group_counts[OBJECT_TYPE_RIDE]; rideType++)
            {
                rct_ride_entry * master_ride = get_ride_entry(rideType);
                if (master_ride == nullptr)
                    continue;

                if (master_ride->flags & RIDE_ENTRY_FLAG_SEPARATE_RIDE)
                    continue;

                // If master ride not in use
                if (!(Editor::SelectedObjects[OBJECT_TYPE_RIDE][rideType] & OBJECT_SELECTION_FLAG_SELECTED))
                    continue;

                for (uint8 j = 0; j < MAX_RIDE_TYPES_PER_RIDE_ENTRY; j++)
                {
                    if (master_ride->ride_type[j] == ride_base_type)
                    {
                        master_found = true;
                        break;
                    }
                }

                if (master_found)
                {
                    break;
                }
            }
        }

        if (!master_found){
            // If not in use
            if (!(Editor::SelectedObjects[OBJECT_TYPE_RIDE][object_index] & OBJECT_SELECTION_FLAG_SELECTED)) {
                continue;
            }

            bool foundBaseType = false;
            for (uint8 j = 0; j < MAX_RIDE_TYPES_PER_RIDE_ENTRY; j++) {
                if (ride_entry->ride_type[j] == ride_base_type) {
                    foundBaseType = true;
                }
            }

            if (!foundBaseType) {
                continue;
            }
        }

        research->entryIndex |= RESEARCH_ENTRY_FLAG_RIDE_ALWAYS_RESEARCHED;
        _editorInventionsListDraggedItem = research;
        move_research_item(gResearchItems);
        _editorInventionsListDraggedItem = nullptr;
        research--;
    }
}

/**
 *
 *  rct2: 0x0068590C
 * Sets the critical scenery sets to always researched
 */
static void research_scenery_sets_setup(){

    for (size_t i = 0; i < Util::CountOf(RequiredSelectedObjects); i++) {
        const rct_object_entry * object = &RequiredSelectedObjects[i];

        uint8 entry_type, entry_index;
        if (!find_object_in_entry_group(object, &entry_type, &entry_index))
            continue;

        if (entry_type != OBJECT_TYPE_SCENERY_GROUP)
            continue;

        rct_research_item* research = gResearchItems;
        for (; research->entryIndex != RESEARCHED_ITEMS_END; research++){

            if ((research->entryIndex & 0xFFFFFF) != entry_index)
                continue;

            research->entryIndex |= RESEARCH_ENTRY_FLAG_SCENERY_SET_ALWAYS_RESEARCHED;
            _editorInventionsListDraggedItem = research;
            move_research_item(gResearchItems);
            _editorInventionsListDraggedItem = nullptr;
        }
    }
}

/**
 *
 *  rct2: 0x00685901
 */
static void research_always_researched_setup()
{
    research_rides_setup();
    research_scenery_sets_setup();
}

/**
 *
 *  rct2: 0x00685A93
 */
static void research_items_shuffle()
{
    rct_research_item *researchItem, *researchOrderBase, researchItemTemp;
    sint32 i, numNonResearchedItems;

    // Skip pre-researched items
    for (researchItem = gResearchItems; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) {}
    researchItem++;
    researchOrderBase = researchItem;

    // Count non pre-researched items
    numNonResearchedItems = 0;
    for (; researchItem->entryIndex != RESEARCHED_ITEMS_END; researchItem++)
        numNonResearchedItems++;

    // Shuffle list
    for (i = 0; i < numNonResearchedItems; i++) {
        sint32 ri = util_rand() % numNonResearchedItems;
        if (ri == i)
            continue;

        researchItemTemp = researchOrderBase[i];
        researchOrderBase[i] = researchOrderBase[ri];
        researchOrderBase[ri] = researchItemTemp;
    }
}

static void research_items_make_all_unresearched()
{
    rct_research_item *researchItem, *nextResearchItem, researchItemTemp;

    sint32 sorted;
    do {
        sorted = 1;
        for (researchItem = gResearchItems; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) {
            if (research_item_is_always_researched(researchItem))
                continue;

            nextResearchItem = researchItem + 1;
            if (nextResearchItem->entryIndex == RESEARCHED_ITEMS_SEPARATOR || research_item_is_always_researched(nextResearchItem)) {
                // Bubble up always researched item or separator
                researchItemTemp = *researchItem;
                *researchItem = *nextResearchItem;
                *nextResearchItem = researchItemTemp;
                sorted = 0;

                if (researchItem->entryIndex == RESEARCHED_ITEMS_SEPARATOR)
                    break;
            }
        }
    } while (!sorted);
}

static void research_items_make_all_researched()
{
    rct_research_item *researchItem, researchItemTemp;

    // Find separator
    for (researchItem = gResearchItems; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) { }

    // Move separator below all items
    for (; (researchItem + 1)->entryIndex != RESEARCHED_ITEMS_END; researchItem++) {
        // Swap separator with research item
        researchItemTemp = *researchItem;
        *researchItem = *(researchItem + 1);
        *(researchItem + 1) = researchItemTemp;
    }
}

/**
 *
 *  rct2: 0x006855E7
 */
static void move_research_item(rct_research_item *beforeItem)
{
    rct_window *w;
    rct_research_item *researchItem, draggedItem;

    if (_editorInventionsListDraggedItem + 1 == beforeItem)
        return;

    // Back up the dragged item
    draggedItem = *_editorInventionsListDraggedItem;

    // Remove dragged item from list
    researchItem = _editorInventionsListDraggedItem;
    do {
        *researchItem = *(researchItem + 1);
        researchItem++;
    } while (researchItem->entryIndex != RESEARCHED_ITEMS_END_2);
    // At end of this researchItem points to the end of the list

    if (beforeItem > _editorInventionsListDraggedItem)
        beforeItem--;

    // Add dragged item to list
    do {
        *researchItem = *(researchItem - 1);
        researchItem--;
    } while (researchItem != beforeItem);

    *researchItem = draggedItem;

    w = window_find_by_class(WC_EDITOR_INVENTION_LIST);
    if (w != nullptr) {
        w->research_item = nullptr;
        window_invalidate(w);
    }
}

/**
 *
 *  rct2: 0x0068558E
 */
static rct_research_item *window_editor_inventions_list_get_item_from_scroll_y(sint32 scrollIndex, sint32 y)
{
    rct_research_item *researchItem;

    researchItem = gResearchItems;

    if (scrollIndex != 0) {
        // Skip pre-researched items
        for (; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) { }
        researchItem++;
    }

    for (; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR && researchItem->entryIndex != RESEARCHED_ITEMS_END; researchItem++) {
        y -= SCROLLABLE_ROW_HEIGHT;
        if (y < 0)
            return researchItem;
    }

    return nullptr;
}

/**
 *
 *  rct2: 0x006855BB
 */
static rct_research_item *window_editor_inventions_list_get_item_from_scroll_y_include_seps(sint32 scrollIndex, sint32 y)
{
    rct_research_item *researchItem;

    researchItem = gResearchItems;

    if (scrollIndex != 0) {
        // Skip pre-researched items
        for (; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) { }
        researchItem++;
    }

    for (; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR && researchItem->entryIndex != RESEARCHED_ITEMS_END; researchItem++) {
        y -= SCROLLABLE_ROW_HEIGHT;
        if (y < 0)
            return researchItem;
    }

    return researchItem;
}

static rct_research_item *get_research_item_at(sint32 x, sint32 y)
{
    rct_window *w = window_find_by_class(WC_EDITOR_INVENTION_LIST);
    if (w != nullptr && w->x <= x && w->y < y && w->x + w->width > x && w->y + w->height > y) {
        rct_widgetindex widgetIndex = window_find_widget_from_point(w, x, y);
        rct_widget *widget = &w->widgets[widgetIndex];
        if (widgetIndex == WIDX_PRE_RESEARCHED_SCROLL || widgetIndex == WIDX_RESEARCH_ORDER_SCROLL) {
            gPressedWidget.widget_index = widgetIndex;
            sint32 outX, outY, outScrollArea, outScrollId;
            widget_scroll_get_part(w, widget, x, y, &outX, &outY, &outScrollArea, &outScrollId);
            if (outScrollArea == SCROLL_PART_VIEW) {
                outScrollId = outScrollId == 0 ? 0 : 1;

                sint32 scrollY = y - (w->y + widget->top) + w->scrolls[outScrollId].v_top + 5;
                return window_editor_inventions_list_get_item_from_scroll_y_include_seps(outScrollId, scrollY);
            }
        }
    }

    return nullptr;
}

/**
 *
 *  rct2: 0x00684E04
 */
rct_window * window_editor_inventions_list_open()
{
    rct_window *w;

    w = window_bring_to_front_by_class(WC_EDITOR_INVENTION_LIST);
    if (w != nullptr)
        return w;

    research_always_researched_setup();

    w = window_create_centred(
        600,
        400,
        &window_editor_inventions_list_events,
        WC_EDITOR_INVENTION_LIST,
        WF_NO_SCROLLING
    );
    w->widgets = window_editor_inventions_list_widgets;
    w->enabled_widgets =
        (1 << WIDX_CLOSE) |
        (1 << WIDX_TAB_1) |
        (1 << WIDX_RANDOM_SHUFFLE) |
        (1 << WIDX_MOVE_ITEMS_TO_BOTTOM) |
        (1 << WIDX_MOVE_ITEMS_TO_TOP);
    window_init_scroll_widgets(w);
    w->var_4AE = 0;
    w->selected_tab = 0;
    w->research_item = nullptr;
    _editorInventionsListDraggedItem = nullptr;

    return w;
}

/**
 *
 *  rct2: 0x006853D2
 */
static void window_editor_inventions_list_close(rct_window *w)
{
    research_remove_flags();

    // When used in-game (as a cheat)
    if (!(gScreenFlags & SCREEN_FLAGS_EDITOR)) {
        gSilentResearch = true;
        research_reset_current_item();
        gSilentResearch = false;
    }
}

/**
 *
 *  rct2: 0x0068521B
 */
static void window_editor_inventions_list_mouseup(rct_window *w, rct_widgetindex widgetIndex)
{
    switch (widgetIndex) {
    case WIDX_CLOSE:
        window_close(w);
        break;
    case WIDX_RANDOM_SHUFFLE:
        research_items_shuffle();
        window_invalidate(w);
        break;
    case WIDX_MOVE_ITEMS_TO_TOP:
        research_items_make_all_researched();
        window_init_scroll_widgets(w);
        window_invalidate(w);
        break;
    case WIDX_MOVE_ITEMS_TO_BOTTOM:
        research_items_make_all_unresearched();
        window_init_scroll_widgets(w);
        window_invalidate(w);
        break;
    }
}

/**
 *
 *  rct2: 0x00685392
 */
static void window_editor_inventions_list_update(rct_window *w)
{
    w->frame_no++;
    window_event_invalidate_call(w);
    widget_invalidate(w, WIDX_TAB_1);

    if (_editorInventionsListDraggedItem == nullptr)
        return;

    if (window_find_by_class(WC_EDITOR_INVENTION_LIST_DRAG) != nullptr)
        return;

    _editorInventionsListDraggedItem = nullptr;
    window_invalidate(w);
}

/**
 *
 *  rct2: 0x00685239
 */
static void window_editor_inventions_list_scrollgetheight(rct_window *w, sint32 scrollIndex, sint32 *width, sint32 *height)
{
    rct_research_item *researchItem;

    *height = 0;

    // Count / skip pre-researched items
    for (researchItem = gResearchItems; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++)
        *height += SCROLLABLE_ROW_HEIGHT;

    if (scrollIndex == 1) {
        researchItem++;

        // Count non pre-researched items
        *height = 0;
        for (; researchItem->entryIndex != RESEARCHED_ITEMS_END; researchItem++)
            *height += SCROLLABLE_ROW_HEIGHT;
    }
}

/**
 *
 *  rct2: 0x006852D4
 */
static void window_editor_inventions_list_scrollmousedown(rct_window *w, sint32 scrollIndex, sint32 x, sint32 y)
{
    rct_research_item *researchItem;

    researchItem = window_editor_inventions_list_get_item_from_scroll_y(scrollIndex, y);
    if (researchItem == nullptr)
        return;

    if (researchItem->entryIndex < RESEARCHED_ITEMS_END_2 && research_item_is_always_researched(researchItem))
        return;

    window_invalidate(w);
    window_editor_inventions_list_drag_open(researchItem);
}

/**
 *
 *  rct2: 0x00685275
 */
static void window_editor_inventions_list_scrollmouseover(rct_window *w, sint32 scrollIndex, sint32 x, sint32 y)
{
    rct_research_item *researchItem;

    researchItem = window_editor_inventions_list_get_item_from_scroll_y(scrollIndex, y);
    if (researchItem != w->research_item) {
        w->research_item = researchItem;
        window_invalidate(w);
    }
}

/**
 *
 *  rct2: 0x0068526B
 */
static void window_editor_inventions_list_tooltip(rct_window* w, rct_widgetindex widgetIndex, rct_string_id *stringId)
{
    set_format_arg(0, rct_string_id, STR_LIST);
}

/**
 *
 *  rct2: 0x00685291
 */
static void window_editor_inventions_list_cursor(rct_window *w, rct_widgetindex widgetIndex, sint32 x, sint32 y, sint32 *cursorId)
{
    rct_research_item *researchItem;
    sint32 scrollIndex;

    switch (widgetIndex) {
    case WIDX_PRE_RESEARCHED_SCROLL:
        scrollIndex = 0;
        break;
    case WIDX_RESEARCH_ORDER_SCROLL:
        scrollIndex = 1;
        break;
    default:
        return;
    }

    researchItem = window_editor_inventions_list_get_item_from_scroll_y(scrollIndex, y);
    if (researchItem == nullptr)
        return;

    if (researchItem->entryIndex < RESEARCHED_ITEMS_END_2 && research_item_is_always_researched(researchItem)) {
        return;
    }

    *cursorId = CURSOR_HAND_OPEN;
}

/**
 *
 *  rct2: 0x00685392
 */
static void window_editor_inventions_list_invalidate(rct_window *w)
{
    w->pressed_widgets |= 1 << WIDX_PREVIEW;
    w->pressed_widgets |= 1 << WIDX_TAB_1;

    w->widgets[WIDX_CLOSE].type =
        gScreenFlags & SCREEN_FLAGS_SCENARIO_EDITOR ? WWT_EMPTY : WWT_CLOSEBOX;
}

/**
 *
 *  rct2: 0x00684EE0
 */
static void window_editor_inventions_list_paint(rct_window *w, rct_drawpixelinfo *dpi)
{
    rct_widget *widget;
    rct_research_item *researchItem;
    rct_string_id stringId;
    sint32 x, y, width;

    window_draw_widgets(w, dpi);

    // Tab image
    x = w->x + w->widgets[WIDX_TAB_1].left;
    y = w->y + w->widgets[WIDX_TAB_1].top;
    gfx_draw_sprite(dpi, SPR_TAB_FINANCES_RESEARCH_0 + (w->frame_no / 2) % 8, x, y, 0);

    // Pre-researched items label
    x = w->x + w->widgets[WIDX_PRE_RESEARCHED_SCROLL].left;
    y = w->y + w->widgets[WIDX_PRE_RESEARCHED_SCROLL].top - 11;
    gfx_draw_string_left(dpi, STR_INVENTION_PREINVENTED_ITEMS, nullptr, COLOUR_BLACK, x, y - 1);

    // Research order label
    x = w->x + w->widgets[WIDX_RESEARCH_ORDER_SCROLL].left;
    y = w->y + w->widgets[WIDX_RESEARCH_ORDER_SCROLL].top - 11;
    gfx_draw_string_left(dpi, STR_INVENTION_TO_BE_INVENTED_ITEMS, nullptr, COLOUR_BLACK, x, y - 1);

    // Preview background
    widget = &w->widgets[WIDX_PREVIEW];
    gfx_fill_rect(
        dpi,
        w->x + widget->left + 1,
        w->y + widget->top + 1,
        w->x + widget->right - 1,
        w->y + widget->bottom - 1,
        ColourMapA[w->colours[1]].darkest
    );

    researchItem = _editorInventionsListDraggedItem;
    if (researchItem == nullptr)
        researchItem = w->research_item;
    // If the research item is null or a list separator.
    if (researchItem == nullptr || researchItem->entryIndex < 0)
        return;

    // Preview image
    sint32 objectEntryType = 7;
    sint32 eax = researchItem->entryIndex & 0xFFFFFF;
    if (eax >= 0x10000)
        objectEntryType = 0;

    void *chunk = object_entry_groups[objectEntryType].chunks[researchItem->entryIndex & 0xFF];

    if (chunk == nullptr)
        return;

    rct_object_entry * entry = &object_entry_groups[objectEntryType].entries[researchItem->entryIndex & 0xFF].entry;

    // Draw preview
    widget = &w->widgets[WIDX_PREVIEW];

    void * object = object_manager_get_loaded_object(entry);
    if (object != nullptr) {
        rct_drawpixelinfo clipDPI;
        x = w->x + widget->left + 1;
        y = w->y + widget->top + 1;
        width = widget->right - widget->left - 1;
        sint32 height = widget->bottom - widget->top - 1;
        if (clip_drawpixelinfo(&clipDPI, dpi, x, y, width, height)) {
            object_draw_preview(object, &clipDPI, width, height);
        }
    }

    // Item name
    x = w->x + ((widget->left + widget->right) / 2) + 1;
    y = w->y + widget->bottom + 3;
    width = w->width - w->widgets[WIDX_RESEARCH_ORDER_SCROLL].right - 6;
    stringId = research_item_get_name(eax);
    gfx_draw_string_centred_clipped(dpi, STR_WINDOW_COLOUR_2_STRINGID, &stringId, COLOUR_BLACK, x, y, width);
    y += 15;

    // Item category
    x = w->x + w->widgets[WIDX_RESEARCH_ORDER_SCROLL].right + 4;
    stringId = EditorInventionsResearchCategories[researchItem->category];
    gfx_draw_string_left(dpi, STR_INVENTION_RESEARCH_GROUP, &stringId, COLOUR_BLACK, x, y);
}

/**
 *
 *  rct2: 0x006850BD
 */
static void window_editor_inventions_list_scrollpaint(rct_window *w, rct_drawpixelinfo *dpi, sint32 scrollIndex)
{
    rct_research_item *researchItem;
    sint32 left, top, bottom, itemY, disableItemMovement;
    sint32 researchItemEndMarker;
    rct_string_id stringId;
    utf8 buffer[256], *ptr;

    // Draw background
    uint8 paletteIndex = ColourMapA[w->colours[1]].mid_light;
    gfx_clear(dpi, paletteIndex);

    researchItem = gResearchItems;

    if (scrollIndex == 1) {
        // Skip pre-researched items
        for (; researchItem->entryIndex != RESEARCHED_ITEMS_SEPARATOR; researchItem++) { }
        researchItem++;
        researchItemEndMarker = RESEARCHED_ITEMS_END;
    } else {
        researchItemEndMarker = RESEARCHED_ITEMS_SEPARATOR;
    }

    // Since this is now a do while need to counteract the +SCROLLABLE_ROW_HEIGHT
    itemY = -SCROLLABLE_ROW_HEIGHT;
    do
    {
        itemY += SCROLLABLE_ROW_HEIGHT;
        if (itemY + SCROLLABLE_ROW_HEIGHT < dpi->y || itemY >= dpi->y + dpi->height)
            continue;

        uint8 colour = COLOUR_BRIGHT_GREEN | COLOUR_FLAG_TRANSLUCENT;
        if (w->research_item == researchItem) {
            if (_editorInventionsListDraggedItem == nullptr) {
                // Highlight
                top = itemY;
                bottom = itemY + SCROLLABLE_ROW_HEIGHT - 1;
            } else {
                // Drop horizontal rule
                top = itemY - 1;
                bottom = itemY;
            }
            gfx_filter_rect(dpi, 0, top, w->width, bottom, PALETTE_DARKEN_1);

            if (_editorInventionsListDraggedItem == nullptr)
                colour = COLOUR_BRIGHT_GREEN;
        }

        if (researchItem->entryIndex == RESEARCHED_ITEMS_SEPARATOR || researchItem->entryIndex == RESEARCHED_ITEMS_END)
            continue;

        if (researchItem == _editorInventionsListDraggedItem)
            continue;

        disableItemMovement = research_item_is_always_researched(researchItem);
        stringId = research_item_get_name(researchItem->entryIndex & 0xFFFFFF);

        ptr = buffer;
        if (!disableItemMovement) {
            ptr = utf8_write_codepoint(ptr, colour);
        }

        format_string(ptr, 256, stringId, nullptr);

        if (disableItemMovement) {
            gCurrentFontSpriteBase = FONT_SPRITE_BASE_MEDIUM_DARK;
            if (colour == COLOUR_BRIGHT_GREEN && _editorInventionsListDraggedItem == nullptr) {
                gCurrentFontSpriteBase = FONT_SPRITE_BASE_MEDIUM_EXTRA_DARK;
            }
            colour = COLOUR_FLAG_INSET | w->colours[1];
        } else {
            gCurrentFontSpriteBase = FONT_SPRITE_BASE_MEDIUM;
            colour = COLOUR_BLACK;
        }

        left = 1;
        top = itemY;
        gfx_draw_string(dpi, buffer, colour, left, top);
    }while(researchItem++->entryIndex != researchItemEndMarker);
}

#pragma region Drag item

/**
 *
 *  rct2: 0x006852F4
 */
static void window_editor_inventions_list_drag_open(rct_research_item *researchItem)
{
    char buffer[256];
    sint32 stringWidth;
    rct_string_id stringId;
    rct_window *w;

    window_close_by_class(WC_EDITOR_INVENTION_LIST_DRAG);
    _editorInventionsListDraggedItem = researchItem;

    stringId = research_item_get_name(researchItem->entryIndex & 0xFFFFFF);
    format_string(buffer, 256, stringId, nullptr);
    stringWidth = gfx_get_string_width(buffer);
    window_editor_inventions_list_drag_widgets[0].right = stringWidth;

    w = window_create(
        gTooltipCursorX - (stringWidth / 2),
        gTooltipCursorY - 7,
        stringWidth,
        14,
        &window_editor_inventions_list_drag_events,
        WC_EDITOR_INVENTION_LIST_DRAG,
        WF_STICK_TO_FRONT | WF_TRANSPARENT | WF_NO_SNAPPING
    );
    w->widgets = window_editor_inventions_list_drag_widgets;
    w->colours[1] = COLOUR_WHITE;
    input_window_position_begin(w, 0, gTooltipCursorX, gTooltipCursorY);
}

/**
 *
 *  rct2: 0x0068549C
 */
static void window_editor_inventions_list_drag_cursor(rct_window *w, rct_widgetindex widgetIndex, sint32 x, sint32 y, sint32 *cursorId)
{
    rct_window *inventionListWindow = window_find_by_class(WC_EDITOR_INVENTION_LIST);
    if (inventionListWindow != nullptr) {
        rct_research_item *researchItem = get_research_item_at(x, y);
        if (researchItem != inventionListWindow->research_item) {
            inventionListWindow = (rct_window *)researchItem;
            window_invalidate(inventionListWindow);
        }
    }

    *cursorId = CURSOR_HAND_CLOSED;
}

/**
 *
 *  rct2: 0x00685412
 */
static void window_editor_inventions_list_drag_moved(rct_window* w, sint32 x, sint32 y)
{
    rct_research_item *researchItem;

    researchItem = get_research_item_at(x, y);
    if (researchItem != nullptr)
        move_research_item(researchItem);

    window_close(w);
    _editorInventionsListDraggedItem = nullptr;
    window_invalidate_by_class(WC_EDITOR_INVENTION_LIST);
}

/**
 *
 *  rct2: 0x006853D9
 */
static void window_editor_inventions_list_drag_paint(rct_window *w, rct_drawpixelinfo *dpi)
{
    rct_string_id stringId;
    sint32 x, y;

    x = w->x;
    y = w->y + 2;
    stringId = research_item_get_name(_editorInventionsListDraggedItem->entryIndex & 0xFFFFFF);
    gfx_draw_string_left(dpi, STR_WINDOW_COLOUR_2_STRINGID, &stringId, COLOUR_BLACK | COLOUR_FLAG_OUTLINE, x, y);
}

#pragma endregion