(svn r27985) -Codechange: Convert VA2 switches into ones with non-overlapping ranges...

[openttd.git] / src / widgets / dropdown.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 dropdown.cpp Implementation of the dropdown widget. */

#include "../stdafx.h"
#include "../window_gui.h"
#include "../string_func.h"
#include "../strings_func.h"
#include "../window_func.h"
#include "dropdown_type.h"

#include "dropdown_widget.h"

#include "../safeguards.h"


void DropDownListItem::Draw(int left, int right, int top, int bottom, bool sel, int bg_colour) const
{
        int c1 = _colour_gradient[bg_colour][3];
        int c2 = _colour_gradient[bg_colour][7];

        int mid = top + this->Height(0) / 2;
        GfxFillRect(left + 1, mid - 2, right - 1, mid - 2, c1);
        GfxFillRect(left + 1, mid - 1, right - 1, mid - 1, c2);
}

uint DropDownListStringItem::Width() const
{
        char buffer[512];
        GetString(buffer, this->String(), lastof(buffer));
        return GetStringBoundingBox(buffer).width;
}

void DropDownListStringItem::Draw(int left, int right, int top, int bottom, bool sel, int bg_colour) const
{
        DrawString(left + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, this->String(), sel ? TC_WHITE : TC_BLACK);
}

/**
 * Natural sorting comparator function for DropDownList::sort().
 * @param first Left side of comparison.
 * @param second Right side of comparison.
 * @return true if \a first precedes \a second.
 * @warning All items in the list need to be derivates of DropDownListStringItem.
 */
/* static */ int DropDownListStringItem::NatSortFunc(const DropDownListItem * const *first, const DropDownListItem * const * second)
{
        char buffer1[512], buffer2[512];
        GetString(buffer1, static_cast<const DropDownListStringItem*>(*first)->String(), lastof(buffer1));
        GetString(buffer2, static_cast<const DropDownListStringItem*>(*second)->String(), lastof(buffer2));
        return strnatcmp(buffer1, buffer2);
}

StringID DropDownListParamStringItem::String() const
{
        for (uint i = 0; i < lengthof(this->decode_params); i++) SetDParam(i, this->decode_params[i]);
        return this->string;
}

StringID DropDownListCharStringItem::String() const
{
        SetDParamStr(0, this->raw_string);
        return this->string;
}

static const NWidgetPart _nested_dropdown_menu_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PANEL, COLOUR_END, WID_DM_ITEMS), SetMinimalSize(1, 1), SetScrollbar(WID_DM_SCROLL), EndContainer(),
                NWidget(NWID_SELECTION, INVALID_COLOUR, WID_DM_SHOW_SCROLL),
                        NWidget(NWID_VSCROLLBAR, COLOUR_END, WID_DM_SCROLL),
                EndContainer(),
        EndContainer(),
};

static WindowDesc _dropdown_desc(
        WDP_MANUAL, NULL, 0, 0,
        WC_DROPDOWN_MENU, WC_NONE,
        WDF_NO_FOCUS,
        _nested_dropdown_menu_widgets, lengthof(_nested_dropdown_menu_widgets)
);

/** Drop-down menu window */
struct DropdownWindow : Window {
        WindowClass parent_wnd_class; ///< Parent window class.
        WindowNumber parent_wnd_num;  ///< Parent window number.
        int parent_button;            ///< Parent widget number where the window is dropped from.
        const DropDownList *list;     ///< List with dropdown menu items.
        int selected_index;           ///< Index of the selected item in the list.
        byte click_delay;             ///< Timer to delay selection.
        bool drag_mode;
        bool instant_close;           ///< Close the window when the mouse button is raised.
        int scrolling;                ///< If non-zero, auto-scroll the item list (one time).
        Point position;               ///< Position of the topleft corner of the window.
        Scrollbar *vscroll;

        /**
         * Create a dropdown menu.
         * @param parent        Parent window.
         * @param list          Dropdown item list.
         * @param selected      Index of the selected item in the list.
         * @param button        Widget of the parent window doing the dropdown.
         * @param instant_close Close the window when the mouse button is raised.
         * @param position      Topleft position of the dropdown menu window.
         * @param size          Size of the dropdown menu window.
         * @param wi_colour     Colour of the parent widget.
         * @param scroll        Dropdown menu has a scrollbar.
         * @param widget        Widgets of the dropdown menu window.
         */
        DropdownWindow(Window *parent, const DropDownList *list, int selected, int button, bool instant_close, const Point &position, const Dimension &size, Colours wi_colour, bool scroll)
                        : Window(&_dropdown_desc)
        {
                assert(list->Length() > 0);

                this->position = position;

                this->CreateNestedTree();

                this->vscroll = this->GetScrollbar(WID_DM_SCROLL);

                uint items_width = size.width - (scroll ? NWidgetScrollbar::GetVerticalDimension().width : 0);
                NWidgetCore *nwi = this->GetWidget<NWidgetCore>(WID_DM_ITEMS);
                nwi->SetMinimalSize(items_width, size.height + 4);
                nwi->colour = wi_colour;

                nwi = this->GetWidget<NWidgetCore>(WID_DM_SCROLL);
                nwi->colour = wi_colour;

                this->GetWidget<NWidgetStacked>(WID_DM_SHOW_SCROLL)->SetDisplayedPlane(scroll ? 0 : SZSP_NONE);

                this->FinishInitNested(0);
                CLRBITS(this->flags, WF_WHITE_BORDER);

                /* Total length of list */
                int list_height = 0;
                for (const DropDownListItem * const *it = list->Begin(); it != list->End(); ++it) {
                        const DropDownListItem *item = *it;
                        list_height += item->Height(items_width);
                }

                /* Capacity is the average number of items visible */
                this->vscroll->SetCapacity(size.height * (uint16)list->Length() / list_height);
                this->vscroll->SetCount((uint16)list->Length());

                this->parent_wnd_class = parent->window_class;
                this->parent_wnd_num   = parent->window_number;
                this->parent_button    = button;
                this->list             = list;
                this->selected_index   = selected;
                this->click_delay      = 0;
                this->drag_mode        = true;
                this->instant_close    = instant_close;
        }

        ~DropdownWindow()
        {
                /* Make the dropdown "invisible", so it doesn't affect new window placement.
                 * Also mark it dirty in case the callback deals with the screen. (e.g. screenshots). */
                this->window_class = WC_INVALID;
                this->SetDirty();

                Window *w2 = FindWindowById(this->parent_wnd_class, this->parent_wnd_num);
                if (w2 != NULL) {
                        Point pt = _cursor.pos;
                        pt.x -= w2->left;
                        pt.y -= w2->top;
                        w2->OnDropdownClose(pt, this->parent_button, this->selected_index, this->instant_close);
                }
                delete this->list;
        }

        virtual Point OnInitialPosition(int16 sm_width, int16 sm_height, int window_number)
        {
                return this->position;
        }

        /**
         * Find the dropdown item under the cursor.
         * @param value [out] Selected item, if function returns \c true.
         * @return Cursor points to a dropdown item.
         */
        bool GetDropDownItem(int &value)
        {
                if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;

                NWidgetBase *nwi = this->GetWidget<NWidgetBase>(WID_DM_ITEMS);
                int y     = _cursor.pos.y - this->top - nwi->pos_y - 2;
                int width = nwi->current_x - 4;
                int pos   = this->vscroll->GetPosition();

                const DropDownList *list = this->list;

                for (const DropDownListItem * const *it = list->Begin(); it != list->End(); ++it) {
                        /* Skip items that are scrolled up */
                        if (--pos >= 0) continue;

                        const DropDownListItem *item = *it;
                        int item_height = item->Height(width);

                        if (y < item_height) {
                                if (item->masked || !item->Selectable()) return false;
                                value = item->result;
                                return true;
                        }

                        y -= item_height;
                }

                return false;
        }

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

                Colours colour = this->GetWidget<NWidgetCore>(widget)->colour;

                int y = r.top + 2;
                int pos = this->vscroll->GetPosition();
                for (const DropDownListItem * const *it = this->list->Begin(); it != this->list->End(); ++it) {
                        const DropDownListItem *item = *it;
                        int item_height = item->Height(r.right - r.left + 1);

                        /* Skip items that are scrolled up */
                        if (--pos >= 0) continue;

                        if (y + item_height < r.bottom) {
                                bool selected = (this->selected_index == item->result);
                                if (selected) GfxFillRect(r.left + 2, y, r.right - 1, y + item_height - 1, PC_BLACK);

                                item->Draw(r.left, r.right, y, y + item_height, selected, colour);

                                if (item->masked) {
                                        GfxFillRect(r.left + 1, y, r.right - 1, y + item_height - 1, _colour_gradient[colour][5], FILLRECT_CHECKER);
                                }
                        }
                        y += item_height;
                }
        }

        virtual void OnClick(Point pt, int widget, int click_count)
        {
                if (widget != WID_DM_ITEMS) return;
                int item;
                if (this->GetDropDownItem(item)) {
                        this->click_delay = 4;
                        this->selected_index = item;
                        this->SetDirty();
                }
        }

        virtual void OnTick()
        {
                if (this->scrolling != 0) {
                        int pos = this->vscroll->GetPosition();

                        this->vscroll->UpdatePosition(this->scrolling);
                        this->scrolling = 0;

                        if (pos != this->vscroll->GetPosition()) {
                                this->SetDirty();
                        }
                }
        }

        virtual void OnMouseLoop()
        {
                Window *w2 = FindWindowById(this->parent_wnd_class, this->parent_wnd_num);
                if (w2 == NULL) {
                        delete this;
                        return;
                }

                if (this->click_delay != 0 && --this->click_delay == 0) {
                        /* Make the dropdown "invisible", so it doesn't affect new window placement.
                         * Also mark it dirty in case the callback deals with the screen. (e.g. screenshots). */
                        this->window_class = WC_INVALID;
                        this->SetDirty();

                        w2->OnDropdownSelect(this->parent_button, this->selected_index);
                        delete this;
                        return;
                }

                if (this->drag_mode) {
                        int item;

                        if (!_left_button_clicked) {
                                this->drag_mode = false;
                                if (!this->GetDropDownItem(item)) {
                                        if (this->instant_close) delete this;
                                        return;
                                }
                                this->click_delay = 2;
                        } else {
                                if (_cursor.pos.y <= this->top + 2) {
                                        /* Cursor is above the list, set scroll up */
                                        this->scrolling = -1;
                                        return;
                                } else if (_cursor.pos.y >= this->top + this->height - 2) {
                                        /* Cursor is below list, set scroll down */
                                        this->scrolling = 1;
                                        return;
                                }

                                if (!this->GetDropDownItem(item)) return;
                        }

                        if (this->selected_index != item) {
                                this->selected_index = item;
                                this->SetDirty();
                        }
                }
        }
};

/**
 * Show a drop down list.
 * @param w        Parent window for the list.
 * @param list     Prepopulated DropDownList. Will be deleted when the list is
 *                 closed.
 * @param selected The initially selected list item.
 * @param button   The widget which is passed to Window::OnDropdownSelect and OnDropdownClose.
 *                 Unless you override those functions, this should be then widget index of the dropdown button.
 * @param wi_rect  Coord of the parent drop down button, used to position the dropdown menu.
 * @param auto_width The width is determined by the widest item in the list,
 *                   in this case only one of \a left or \a right is used (depending on text direction).
 * @param instant_close Set to true if releasing mouse button should close the
 *                      list regardless of where the cursor is.
 */
void ShowDropDownListAt(Window *w, const DropDownList *list, int selected, int button, Rect wi_rect, Colours wi_colour, bool auto_width, bool instant_close)
{
        DeleteWindowById(WC_DROPDOWN_MENU, 0);

        /* The preferred position is just below the dropdown calling widget */
        int top = w->top + wi_rect.bottom + 1;

        /* The preferred width equals the calling widget */
        uint width = wi_rect.right - wi_rect.left + 1;

        /* Longest item in the list, if auto_width is enabled */
        uint max_item_width = 0;

        /* Total length of list */
        int height = 0;

        for (const DropDownListItem * const *it = list->Begin(); it != list->End(); ++it) {
                const DropDownListItem *item = *it;
                height += item->Height(width);
                if (auto_width) max_item_width = max(max_item_width, item->Width() + 5);
        }

        /* Check if the status bar is visible, as we don't want to draw over it */
        int screen_bottom = GetMainViewBottom();
        bool scroll = false;

        /* Check if the dropdown will fully fit below the widget */
        if (top + height + 4 >= screen_bottom) {
                /* If not, check if it will fit above the widget */
                int screen_top = GetMainViewTop();
                if (w->top + wi_rect.top > screen_top + height) {
                        top = w->top + wi_rect.top - height - 4;
                } else {
                        /* If it doesn't fit above the widget, we need to enable a scrollbar... */
                        int avg_height = height / (int)list->Length();
                        scroll = true;

                        /* ... and choose whether to put the list above or below the widget. */
                        bool put_above = false;
                        int available_height = screen_bottom - w->top - wi_rect.bottom;
                        if (w->top + wi_rect.top - screen_top > available_height) {
                                // Put it above.
                                available_height = w->top + wi_rect.top - screen_top;
                                put_above = true;
                        }

                        /* Check at least there is space for one item. */
                        assert(available_height >= avg_height);

                        /* And lastly, fit the list... */
                        int rows = available_height / avg_height;
                        height = rows * avg_height;

                        /* Add space for the scroll bar if we automatically determined
                         * the width of the list. */
                        max_item_width += NWidgetScrollbar::GetVerticalDimension().width;

                        /* ... and set the top position if needed. */
                        if (put_above) {
                                top = w->top + wi_rect.top - height - 4;
                        }
                }
        }

        if (auto_width) width = max(width, max_item_width);

        Point dw_pos = { w->left + (_current_text_dir == TD_RTL ? wi_rect.right + 1 - (int)width : wi_rect.left), top};
        Dimension dw_size = {width, (uint)height};
        new DropdownWindow(w, list, selected, button, instant_close, dw_pos, dw_size, wi_colour, scroll);
}

/**
 * Show a drop down list.
 * @param w        Parent window for the list.
 * @param list     Prepopulated DropDownList. Will be deleted when the list is
 *                 closed.
 * @param selected The initially selected list item.
 * @param button   The widget within the parent window that is used to determine
 *                 the list's location.
 * @param width    Override the width determined by the selected widget.
 * @param auto_width Maximum width is determined by the widest item in the list.
 * @param instant_close Set to true if releasing mouse button should close the
 *                      list regardless of where the cursor is.
 */
void ShowDropDownList(Window *w, const DropDownList *list, int selected, int button, uint width, bool auto_width, bool instant_close)
{
        /* Our parent's button widget is used to determine where to place the drop
         * down list window. */
        Rect wi_rect;
        NWidgetCore *nwi = w->GetWidget<NWidgetCore>(button);
        wi_rect.left   = nwi->pos_x;
        wi_rect.right  = nwi->pos_x + nwi->current_x - 1;
        wi_rect.top    = nwi->pos_y;
        wi_rect.bottom = nwi->pos_y + nwi->current_y - 1;
        Colours wi_colour = nwi->colour;

        if ((nwi->type & WWT_MASK) == NWID_BUTTON_DROPDOWN) {
                nwi->disp_flags |= ND_DROPDOWN_ACTIVE;
        } else {
                w->LowerWidget(button);
        }
        w->SetWidgetDirty(button);

        if (width != 0) {
                if (_current_text_dir == TD_RTL) {
                        wi_rect.left = wi_rect.right + 1 - width;
                } else {
                        wi_rect.right = wi_rect.left + width - 1;
                }
        }

        ShowDropDownListAt(w, list, selected, button, wi_rect, wi_colour, auto_width, instant_close);
}

/**
 * Show a dropdown menu window near a widget of the parent window.
 * The result code of the items is their index in the \a strings list.
 * @param w             Parent window that wants the dropdown menu.
 * @param strings       Menu list, end with #INVALID_STRING_ID
 * @param selected      Index of initial selected item.
 * @param button        Button widget number of the parent window \a w that wants the dropdown menu.
 * @param disabled_mask Bitmask for disabled items (items with their bit set are displayed, but not selectable in the dropdown list).
 * @param hidden_mask   Bitmask for hidden items (items with their bit set are not copied to the dropdown list).
 * @param width         Width of the dropdown menu. If \c 0, use the width of parent widget \a button.
 */
void ShowDropDownMenu(Window *w, const StringID *strings, int selected, int button, uint32 disabled_mask, uint32 hidden_mask, uint width)
{
        DropDownList *list = new DropDownList();

        for (uint i = 0; strings[i] != INVALID_STRING_ID; i++) {
                if (!HasBit(hidden_mask, i)) {
                        *list->Append() = new DropDownListStringItem(strings[i], i, HasBit(disabled_mask, i));
                }
        }

        /* No entries in the list? */
        if (list->Length() == 0) {
                delete list;
                return;
        }

        ShowDropDownList(w, list, selected, button, width);
}

/**
 * Delete the drop-down menu from window \a pw
 * @param pw Parent window of the drop-down menu window
 * @return Parent widget number if the drop-down was found and closed, \c -1 if the window was not found.
 */
int HideDropDownMenu(Window *pw)
{
        Window *w;
        FOR_ALL_WINDOWS_FROM_BACK(w) {
                if (w->window_class != WC_DROPDOWN_MENU) continue;

                DropdownWindow *dw = dynamic_cast<DropdownWindow*>(w);
                assert(dw != NULL);
                if (pw->window_class == dw->parent_wnd_class &&
                                pw->window_number == dw->parent_wnd_num) {
                        int parent_button = dw->parent_button;
                        delete dw;
                        return parent_button;
                }
        }

        return -1;
}