dropdown.cpp

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/* $Id: dropdown.cpp 14168 2008-08-25 16:07:10Z peter1138 $ */

#include "../stdafx.h"
#include "../openttd.h"
#include "../strings_type.h"
#include "../window_gui.h"
#include "../strings_func.h"
#include "../strings_type.h"
#include "../gfx_func.h"
#include "../window_func.h"
#include "../core/math_func.hpp"
#include "dropdown_type.h"
#include "dropdown_func.h"

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

void DropDownListItem::Draw(int x, int y, uint width, uint height, bool sel, int bg_colour) const
{
  int c1 = _colour_gradient[bg_colour][3];
  int c2 = _colour_gradient[bg_colour][7];

  GfxFillRect(x + 1, y + 3, x + width - 2, y + 3, c1);
  GfxFillRect(x + 1, y + 4, x + width - 2, y + 4, c2);
}

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

void DropDownListStringItem::Draw(int x, int y, uint width, uint height, bool sel, int bg_colour) const
{
  DrawStringTruncated(x + 2, y, this->String(), sel ? TC_WHITE : TC_BLACK, width);
}

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

static void DeleteDropDownList(DropDownList *list)
{
  for (DropDownList::iterator it = list->begin(); it != list->end(); ++it) {
    DropDownListItem *item = *it;
    delete item;
  }
  delete list;
}

static const Widget _dropdown_menu_widgets[] = {
{      WWT_PANEL,   RESIZE_NONE,  COLOUR_END,     0, 0,     0, 0, 0x0, STR_NULL},
{  WWT_SCROLLBAR,   RESIZE_NONE,  COLOUR_END,     0, 0,     0, 0, 0x0, STR_0190_SCROLL_BAR_SCROLLS_LIST},
{   WIDGETS_END},
};

struct DropdownWindow : Window {
  WindowClass parent_wnd_class;
  WindowNumber parent_wnd_num;
  byte parent_button;
  DropDownList *list;
  int selected_index;
  byte click_delay;
  bool drag_mode;
  bool instant_close;
  int scrolling;

  DropdownWindow(int x, int y, int width, int height, const Widget *widget) : Window(x, y, width, height, WC_DROPDOWN_MENU, widget)
  {
    this->FindWindowPlacementAndResize(width, height);
  }

  ~DropdownWindow()
  {
    Window *w2 = FindWindowById(this->parent_wnd_class, this->parent_wnd_num);
    if (w2 != NULL) {
      w2->RaiseWidget(this->parent_button);
      w2->InvalidateWidget(this->parent_button);
    }

    DeleteDropDownList(this->list);
  }

  bool GetDropDownItem(int &value)
  {
    if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;

    int y     = _cursor.pos.y - this->top - 2;
    int width = this->widget[0].right - 3;
    int pos   = this->vscroll.pos;

    const DropDownList *list = this->list;

    for (DropDownList::const_iterator 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 OnPaint()
  {
    this->DrawWidgets();

    int x = 1;
    int y = 2;

    int sel    = this->selected_index;
    int width  = this->widget[0].right - 2;
    int height = this->widget[0].bottom;
    int pos    = this->vscroll.pos;

    DropDownList *list = this->list;

    for (DropDownList::const_iterator it = list->begin(); it != list->end(); ++it) {
      const DropDownListItem *item = *it;
      int item_height = item->Height(width);

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

      if (y + item_height < height) {
        if (sel == item->result) GfxFillRect(x + 1, y, x + width - 1, y + item_height - 1, 0);

        item->Draw(x, y, width, height, sel == item->result, (TextColour)this->widget[0].color);

        if (item->masked) {
          GfxFillRect(x, y, x + width - 1, y + item_height - 1,
            _colour_gradient[this->widget[0].color][5], FILLRECT_CHECKER
          );
        }
      }
      y += item_height;
    }
  };

  virtual void OnClick(Point pt, int widget)
  {
    if (widget != 0) return;
    int item;
    if (this->GetDropDownItem(item)) {
      this->click_delay = 4;
      this->selected_index = item;
      this->SetDirty();
    }
  }

  virtual void OnTick()
  {
    if (this->scrolling == -1) {
      this->vscroll.pos = max(0, this->vscroll.pos - 1);
      this->SetDirty();
    } else if (this->scrolling == 1) {
      this->vscroll.pos = min(this->vscroll.count - this->vscroll.cap, this->vscroll.pos + 1);
      this->SetDirty();
    }
    this->scrolling = 0;
  }

  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) {
      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) {
            if (GetWidgetFromPos(w2, _cursor.pos.x - w2->left, _cursor.pos.y - w2->top) == this->parent_button) {
              /* Send event for selected option if we're still
               * on the parent button of the list. */
              w2->OnDropdownSelect(this->parent_button, this->selected_index);
            }
            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;
      }

      this->selected_index = item;
      this->SetDirty();
    }
  }
};

void ShowDropDownList(Window *w, DropDownList *list, int selected, int button, uint width, bool auto_width, bool instant_close)
{
  bool is_dropdown_menu_shown = w->IsWidgetLowered(button);

  DeleteWindowById(WC_DROPDOWN_MENU, 0);

  if (is_dropdown_menu_shown) {
    DeleteDropDownList(list);
    return;
  }

  w->LowerWidget(button);
  w->InvalidateWidget(button);

  /* Our parent's button widget is used to determine where to place the drop
   * down list window. */
  const Widget *wi = &w->widget[button];

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

  if (width == 0) width = wi->right - wi->left + 1;

  uint max_item_width = 0;

  if (auto_width) {
    /* Find the longest item in the list */
    for (DropDownList::const_iterator it = list->begin(); it != list->end(); ++it) {
      const DropDownListItem *item = *it;
      max_item_width = max(max_item_width, item->Width() + 5);
    }
  }

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

  for (DropDownList::const_iterator it = list->begin(); it != list->end(); ++it) {
    DropDownListItem *item = *it;
    list_height += item->Height(width);
  }

  /* Height of window visible */
  int height = list_height;

  /* Check if the status bar is visible, as we don't want to draw over it */
  Window *w3 = FindWindowById(WC_STATUS_BAR, 0);
  int screen_bottom = w3 == NULL ? _screen.height : w3->top;

  bool scroll = false;

  /* Check if the dropdown will fully fit below the widget */
  if (top + height + 4 >= screen_bottom) {
    w3 = FindWindowById(WC_MAIN_TOOLBAR, 0);
    int screen_top = w3 == NULL ? 0 : w3->top + w3->height;

    /* If not, check if it will fit above the widget */
    if (w->top + wi->top - height > screen_top) {
      top = w->top + wi->top - height - 4;
    } else {
      /* ... and lastly if it won't, enable the scroll bar and fit the
       * list in below the widget */
      int avg_height = list_height / (int)list->size();
      int rows = (screen_bottom - 4 - top) / avg_height;
      height = rows * avg_height;
      scroll = true;
      /* Add space for the scroll bar if we automatically determined
       * the width of the list. */
      max_item_width += 12;
    }
  }

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

  DropdownWindow *dw = new DropdownWindow(
    w->left + wi->left,
    top,
    width,
    height + 4,
    _dropdown_menu_widgets);

  dw->widget[0].color = wi->color;
  dw->widget[0].right = width - 1;
  dw->widget[0].bottom = height + 3;

  dw->SetWidgetHiddenState(1, !scroll);

  if (scroll) {
    /* We're scrolling, so enable the scroll bar and shrink the list by
     * the scrollbar's width */
    dw->widget[1].color  = wi->color;
    dw->widget[1].right  = dw->widget[0].right;
    dw->widget[1].left   = dw->widget[1].right - 11;
    dw->widget[1].bottom = dw->widget[0].bottom;
    dw->widget[0].right -= 12;

    /* Capacity is the average number of items visible */
    dw->vscroll.cap   = height * (uint16)list->size() / list_height;
    dw->vscroll.count = (uint16)list->size();
  }

  dw->desc_flags = WDF_DEF_WIDGET;
  dw->flags4 &= ~WF_WHITE_BORDER_MASK;

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

void ShowDropDownMenu(Window *w, const StringID *strings, int selected, int button, uint32 disabled_mask, uint32 hidden_mask, uint width)
{
  /* Don't create a new list if we're just closing an existing menu */
  if (w->IsWidgetLowered(button)) {
    DeleteWindowById(WC_DROPDOWN_MENU, 0);
    return;
  }

  uint result = 0;
  DropDownList *list = new DropDownList();

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

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

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

void HideDropDownMenu(Window *pw)
{
  Window **wz;
  FOR_ALL_WINDOWS(wz) {
    if ((*wz)->window_class != WC_DROPDOWN_MENU) continue;

    DropdownWindow *dw = dynamic_cast<DropdownWindow*>(*wz);
    if (pw->window_class == dw->parent_wnd_class &&
        pw->window_number == dw->parent_wnd_num) {
      delete dw;
      break;
    }
  }
}