dropdown.cpp

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/*
 * 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 <https://www.gnu.org/licenses/old-licenses/gpl-2.0>.
 */

 
#include "stdafx.h"
#include "core/backup_type.hpp"
#include "dropdown_type.h"
#include "dropdown_func.h"
#include "stringfilter_type.h"
#include "querystring_gui.h"
#include "strings_func.h"
#include "sound_func.h"
#include "timer/timer.h"
#include "timer/timer_window.h"
#include "window_gui.h"
#include "window_func.h"
#include "zoom_func.h"
 
#include "widgets/dropdown_widget.h"
 
#include "table/strings.h"
 
#include "dropdown_common_type.h"
 
#include "safeguards.h"

std::unique_ptr<DropDownListItem> MakeDropDownListDividerItem()
{
  return std::make_unique<DropDownListDividerItem>(-1);
}

std::unique_ptr<DropDownListItem> MakeDropDownListStringItem(StringID str, int value, bool masked, bool shaded)
{
  return MakeDropDownListStringItem(GetString(str), value, masked, shaded);
}

std::unique_ptr<DropDownListItem> MakeDropDownListStringItem(std::string &&str, int value, bool masked, bool shaded)
{
  return std::make_unique<DropDownListStringItem>(std::move(str), value, masked, shaded);
}

std::unique_ptr<DropDownListItem> MakeDropDownListIconItem(SpriteID sprite, PaletteID palette, StringID str, int value, bool masked, bool shaded)
{
  return std::make_unique<DropDownListIconItem>(sprite, palette, GetString(str), value, masked, shaded);
}

std::unique_ptr<DropDownListItem> MakeDropDownListIconItem(const Dimension &dim, SpriteID sprite, PaletteID palette, StringID str, int value, bool masked, bool shaded)
{
  return std::make_unique<DropDownListIconItem>(dim, sprite, palette, GetString(str), value, masked, shaded);
}

std::unique_ptr<DropDownListItem> MakeDropDownListCheckedItem(bool checked, StringID str, int value, bool masked, bool shaded, uint indent)
{
  return std::make_unique<DropDownListCheckedItem>(indent, checked, GetString(str), value, masked, shaded);
}
 
static constexpr std::initializer_list<NWidgetPart> _nested_dropdown_menu_widgets = {
  NWidget(NWID_VERTICAL),
    NWidget(NWID_SELECTION, INVALID_COLOUR, WID_DM_FILTER_SEL),
      NWidget(WWT_PANEL, COLOUR_END, WID_DM_FILTER_PANEL),
        NWidget(WWT_EDITBOX, COLOUR_END, WID_DM_FILTER), SetResize(1, 0), SetFill(1, 0), SetPadding(2), SetStringTip(STR_LIST_FILTER_OSKTITLE, STR_LIST_FILTER_TOOLTIP),
      EndContainer(),
    EndContainer(),
    NWidget(NWID_HORIZONTAL),
      NWidget(WWT_PANEL, COLOUR_END, WID_DM_ITEMS), SetScrollbar(WID_DM_SCROLL),
      EndContainer(),
      NWidget(NWID_SELECTION, INVALID_COLOUR, WID_DM_SHOW_SCROLL),
        NWidget(NWID_VSCROLLBAR, COLOUR_END, WID_DM_SCROLL),
      EndContainer(),
    EndContainer(),
  EndContainer(),
};

static WindowDesc _dropdown_desc(
  WDP_MANUAL, {}, 0, 0,
  WC_DROPDOWN_MENU, WC_NONE,
  {},
  _nested_dropdown_menu_widgets
);

struct DropdownWindow : Window {
  WidgetID parent_button{}; 
  Rect wi_rect{}; 
  DropDownList list{}; 
  int selected_result = 0; 
  int selected_click_result = -1; 
  uint8_t click_delay = 0; 
  bool drag_mode = true;
  bool above = false; 
  DropDownOptions options; 
  int scrolling = 0; 
  Point position{}; 
  Scrollbar *vscroll = nullptr;
  std::string * const persistent_filter_text = nullptr; 
 
  Dimension initial_dim{}; 
  Dimension items_dim{}; 
 
  mutable StringFilter string_filter{}; 
  QueryString editbox; 

  DropdownWindow(Window *parent, DropDownList &&list, int selected, WidgetID button, const Rect wi_rect, Colours wi_colour, DropDownOptions options, std::string * const persistent_filter_text)
      : Window(_dropdown_desc)
      , parent_button(button)
      , wi_rect(wi_rect)
      , list(std::move(list))
      , selected_result(selected)
      , options(options)
      , persistent_filter_text(persistent_filter_text)
      , editbox(60 * MAX_CHAR_LENGTH, 60)
  {
    assert(!this->list.empty());
 
    this->parent = parent;
 
    this->CreateNestedTree();
 
    this->GetWidget<NWidgetStacked>(WID_DM_FILTER_SEL)->SetDisplayedPlane(this->options.Test(DropDownOption::Filterable) ? 0 : SZSP_HORIZONTAL);
    this->GetWidget<NWidgetCore>(WID_DM_FILTER_PANEL)->colour = wi_colour;
    this->GetWidget<NWidgetCore>(WID_DM_FILTER)->colour = wi_colour;
    this->GetWidget<NWidgetCore>(WID_DM_ITEMS)->colour = wi_colour;
    this->GetWidget<NWidgetCore>(WID_DM_SCROLL)->colour = wi_colour;
    this->vscroll = this->GetScrollbar(WID_DM_SCROLL);
    this->UpdateSizeAndPosition();
 
    this->querystrings[WID_DM_FILTER] = &this->editbox;
 
    this->FinishInitNested(0);
 
    if (this->options.Test(DropDownOption::Filterable)) {
      this->SetFocusedWidget(WID_DM_FILTER);
      if (this->persistent_filter_text != nullptr && !this->persistent_filter_text->empty()) {
        this->editbox.text.Assign(*this->persistent_filter_text);
        this->UpdateFilter();
      }
    }
 
    this->flags.Reset(WindowFlag::WhiteBorder);
  }
 
  void Close([[maybe_unused]] int data = 0) override
  {
    this->UnfocusFocusedWidget();
 
    /* Finish closing the dropdown, 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::Close();
 
    if (this->persistent_filter_text != nullptr) {
      *this->persistent_filter_text = this->editbox.text.GetText();
    }
 
    Point pt = _cursor.pos;
    pt.x -= this->parent->left;
    pt.y -= this->parent->top;
    this->parent->OnDropdownClose(pt, this->parent_button, this->selected_result, this->selected_click_result, this->options.Test(DropDownOption::InstantClose));
 
    /* Set flag on parent widget to indicate that we have just closed. */
    NWidgetCore *nwc = this->parent->GetWidget<NWidgetCore>(this->parent_button);
    if (nwc != nullptr) nwc->disp_flags.Set(NWidgetDisplayFlag::DropdownClosed);
  }
 
  void OnFocusLost(bool closing) override
  {
    if (!closing) {
      this->options.Reset(DropDownOption::InstantClose);
      this->Close();
    }
  }

  uint GetFilterBoxHeight() const
  {
    if (!this->options.Test(DropDownOption::Filterable)) return 0;
 
    /* The edit panel widget does not exist yet so we don't know its real size. Calculate it instead. */
    return GetCharacterHeight(FS_NORMAL) + WidgetDimensions::scaled.fullbevel.Vertical() * 3;
  }

  void FitAvailableHeight(Dimension &desired, const Dimension &list, uint available_height)
  {
    available_height -= this->GetFilterBoxHeight();
 
    if (desired.height < available_height) return;
 
    /* If the dropdown doesn't fully fit, we a need a dropdown. */
    uint avg_height = list.height / (uint)this->list.size();
    uint rows = std::max((available_height - WidgetDimensions::scaled.dropdownlist.Vertical()) / avg_height, 1U);
 
    desired.width = std::max(list.width, desired.width - NWidgetScrollbar::GetVerticalDimension().width);
    desired.height = rows * avg_height + WidgetDimensions::scaled.dropdownlist.Vertical();
  }

  uint GetVisibleHeight() const
  {
    uint height = 0;
    for (const auto &item : this->list) {
      if (!this->FilterByText(*item)) continue;
      height += item->Height();
    }
    return height;
  }

  void UpdateSizeAndPosition()
  {
    Rect button_rect = this->wi_rect.Translate(this->parent->left, this->parent->top);
 
    /* Get the dimensions required for the list. */
    Dimension list_dim = GetDropDownListDimension(this->list);
 
    /* Set up dimensions for the items widget. */
    Dimension widget_dim = list_dim;
    widget_dim.width += WidgetDimensions::scaled.dropdownlist.Horizontal();
    widget_dim.height += WidgetDimensions::scaled.dropdownlist.Vertical();
 
    /* Width should match at least the width of the parent widget. */
    widget_dim.width = std::max<uint>(widget_dim.width, button_rect.Width());
 
    /* Available height below (or above, if the dropdown is placed above the widget). */
    uint available_height_below = std::max(GetMainViewBottom() - button_rect.bottom - 1, 0);
    uint available_height_above = std::max(button_rect.top - 1 - GetMainViewTop(), 0);
 
    /* Is it better to place the dropdown above the widget? */
    if (widget_dim.height > available_height_below && available_height_above > available_height_below) {
      FitAvailableHeight(widget_dim, list_dim, available_height_above);
      this->above = true;
      this->position.y = button_rect.top - widget_dim.height - this->GetFilterBoxHeight();
      this->GetWidget<NWidgetCore>(WID_DM_FILTER_PANEL)->GetParentWidget<NWidgetVertical>()->bottom_up = true;
    } else {
      FitAvailableHeight(widget_dim, list_dim, available_height_below);
      this->above = false;
      this->position.y = button_rect.bottom + 1;
      this->GetWidget<NWidgetCore>(WID_DM_FILTER_PANEL)->GetParentWidget<NWidgetVertical>()->bottom_up = false;
    }
 
    if (_current_text_dir == TD_RTL) {
      /* In case the list is wider than the parent button, the list should be right aligned to the button and overflow to the left. */
      this->position.x = button_rect.right + 1 - (int)(widget_dim.width + (list_dim.height > widget_dim.height ? NWidgetScrollbar::GetVerticalDimension().width : 0));
    } else {
      this->position.x = button_rect.left;
    }
 
    this->initial_dim = widget_dim;
    this->items_dim = widget_dim;
    this->GetWidget<NWidgetStacked>(WID_DM_SHOW_SCROLL)->SetDisplayedPlane(list_dim.height > widget_dim.height ? 0 : SZSP_NONE);
 
    /* Capacity is the average number of items visible */
    this->vscroll->SetCapacity(widget_dim.height - WidgetDimensions::scaled.dropdownlist.Vertical());
    this->vscroll->SetStepSize(list_dim.height / this->list.size());
    this->vscroll->SetCount(this->GetVisibleHeight());
 
    /* If the dropdown is positioned above the parent widget, start selection at the bottom. */
    if (this->above) this->vscroll->SetPosition(INT_MAX);
  }
 
  void UpdateWidgetSize(WidgetID widget, Dimension &size, [[maybe_unused]] const Dimension &padding, [[maybe_unused]] Dimension &fill, [[maybe_unused]] Dimension &resize) override
  {
    if (widget == WID_DM_ITEMS) size = this->items_dim;
  }
 
  Point OnInitialPosition([[maybe_unused]] int16_t sm_width, [[maybe_unused]] int16_t sm_height, [[maybe_unused]] int window_number) override
  {
    return this->position;
  }

  bool GetDropDownItem(int &result, int &click_result)
  {
    if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;
 
    const Rect &r = this->GetWidget<NWidgetBase>(WID_DM_ITEMS)->GetCurrentRect().Shrink(WidgetDimensions::scaled.dropdownlist).Shrink(WidgetDimensions::scaled.dropdowntext, RectPadding::zero);
    int click_y = _cursor.pos.y - this->top - r.top;
    int y = -this->vscroll->GetPosition();
    int y_end = r.Height();
 
    for (const auto &item : this->list) {
      if (!this->FilterByText(*item)) continue;
      int item_height = item->Height();
 
      /* Skip items that are scrolled up */
      if (y > y_end) break;
      if (click_y >= y && click_y < y + item_height) {
        if (item->masked || !item->Selectable()) return false;
        result = item->result;
        click_result = item->OnClick(r.WithY(0, item_height - 1), {_cursor.pos.x - this->left, click_y - y});
        return true;
      }
      y += item_height;
    }
 
    return false;
  }

  bool FilterByText(const DropDownListItem &item) const
  {
    /* Do not filter if the filter text box is empty */
    if (this->string_filter.IsEmpty()) return true;
 
    /* Filter table name */
    this->string_filter.ResetState();
    item.FilterText(this->string_filter);
 
    return this->string_filter.GetState();
  }
 
  void DrawWidget(const Rect &r, WidgetID widget) const override
  {
    if (widget != WID_DM_ITEMS) return;
 
    Colours colour = this->GetWidget<NWidgetCore>(widget)->colour;
 
    Rect ir = r.Shrink(WidgetDimensions::scaled.dropdownlist);
    if (ir.Height() == 0) return;
 
    /* Setup a clipping rectangle... */
    DrawPixelInfo tmp_dpi;
    if (!FillDrawPixelInfo(&tmp_dpi, ir)) return;
    /* ...but keep coordinates relative to the window. */
    tmp_dpi.left += ir.left;
    tmp_dpi.top += ir.top;
    AutoRestoreBackup dpi_backup(_cur_dpi, &tmp_dpi);
 
    int y = -this->vscroll->GetPosition();
    int y_end = ir.Height();
 
    for (const auto &item : this->list) {
      if (!this->FilterByText(*item)) continue;
      int item_height = item->Height();
 
      /* Skip items that are scrolled up */
      if (y > y_end) break;
      if (y > -item_height) {
        Rect full = ir.Translate(0, y).WithHeight(item_height);
 
        bool selected = (this->selected_result == item->result) && item->Selectable() && this->selected_click_result < 0;
        if (selected) GfxFillRect(full, PC_BLACK);
 
        item->Draw(full, full.Shrink(WidgetDimensions::scaled.dropdowntext, RectPadding::zero), selected, selected ? this->selected_click_result : -1, colour);
      }
      y += item_height;
    }
  }
 
  void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
  {
    if (widget != WID_DM_ITEMS) return;
    int result, click_result;
    if (this->GetDropDownItem(result, click_result)) {
      this->click_delay = 4;
      this->selected_result = result;
      this->selected_click_result = click_result;
      this->SetDirty();
    }
  }

  const IntervalTimer<TimerWindow> scroll_interval = {std::chrono::milliseconds(30), [this](auto) {
    if (this->scrolling == 0) return;
 
    if (this->vscroll->UpdatePosition(this->scrolling)) this->SetDirty();
 
    this->scrolling = 0;
  }};
 
  void OnMouseLoop() override
  {
    if (this->click_delay != 0 && --this->click_delay == 0) {
      /* Close the dropdown, so it doesn't affect new window placement.
       * Also mark it dirty in case the callback deals with the screen. (e.g. screenshots). */
      if (!this->options.Test(DropDownOption::Persist)) this->Close();
      this->parent->OnDropdownSelect(this->parent_button, this->selected_result, this->selected_click_result);
      return;
    }
 
    if (this->drag_mode) {
      int result, click_result;
 
      if (!_left_button_clicked) {
        this->drag_mode = false;
        if (!this->GetDropDownItem(result, click_result)) {
          if (this->options.Test(DropDownOption::InstantClose)) this->Close();
          return;
        }
        this->click_delay = 2;
      } else {
        if (_cursor.pos.y <= this->top + WidgetDimensions::scaled.dropdownlist.top) {
          /* Cursor is above the list, set scroll up */
          this->scrolling = -1;
          return;
        } else if (_cursor.pos.y >= this->top + this->height - WidgetDimensions::scaled.dropdownlist.bottom) {
          /* Cursor is below list, set scroll down */
          this->scrolling = 1;
          return;
        }
 
        if (!this->GetDropDownItem(result, click_result)) return;
      }
 
      if (this->selected_result != result || this->selected_click_result != click_result) {
        this->selected_result = result;
        this->selected_click_result = click_result;
        this->SetDirty();
      }
    }
  }
 
  void ReplaceList(DropDownList &&list, std::optional<int> selected_result)
  {
    this->list = std::move(list);
    if (selected_result.has_value()) this->selected_result = *selected_result;
    this->UpdateSizeAndPosition();
    this->ReInit();
    this->InitializePositionSize(this->position.x, this->position.y, this->nested_root->smallest_x, this->nested_root->smallest_y);
    this->FindWindowPlacementAndResize(this->window_desc.GetDefaultWidth(), this->window_desc.GetDefaultHeight(), true);
    this->SetDirty();
  }
 
  void OnResize() override
  {
    this->vscroll->SetCapacity(this->items_dim.height - WidgetDimensions::scaled.dropdownlist.Vertical());
  }

  void UpdateFilter()
  {
    this->string_filter.SetFilterTerm(this->editbox.text.GetText());
 
    uint height = this->GetVisibleHeight();
    uint old_height = this->items_dim.height;
    this->items_dim.height = std::min(this->initial_dim.height, height + WidgetDimensions::scaled.dropdownlist.Vertical());
    this->vscroll->SetCount(height);
 
    if (old_height != this->items_dim.height) {
      this->ReInit();
      if (this->above) {
        /* Drop down list needs to be moved to near the parent drop down button. */
        Rect button_rect = this->wi_rect.Translate(this->parent->left, this->parent->top);
        this->top = button_rect.top - this->items_dim.height - this->GetFilterBoxHeight();
        this->SetDirty();
      }
    } else {
      this->SetDirty();
    }
  }
 
  void OnEditboxChanged(WidgetID wid) override
  {
    if (wid != WID_DM_FILTER) return;
    this->UpdateFilter();
  }
};
 
void ReplaceDropDownList(Window *parent, DropDownList &&list, std::optional<int> selected_result)
{
  DropdownWindow *ddw = dynamic_cast<DropdownWindow *>(parent->FindChildWindow(WC_DROPDOWN_MENU));
  if (ddw != nullptr) ddw->ReplaceList(std::move(list), selected_result);
}

Dimension GetDropDownListDimension(const DropDownList &list)
{
  Dimension dim{};
  for (const auto &item : list) {
    dim.height += item->Height();
    dim.width = std::max(dim.width, item->Width());
  }
  dim.width += WidgetDimensions::scaled.dropdowntext.Horizontal();
  return dim;
}

void ShowDropDownListAt(Window *w, DropDownList &&list, int selected, WidgetID button, Rect wi_rect, Colours wi_colour, DropDownOptions options, std::string * const persistent_filter_text)
{
  CloseWindowByClass(WC_DROPDOWN_MENU);
  new DropdownWindow(w, std::move(list), selected, button, wi_rect, wi_colour, options, persistent_filter_text);
}

void ShowDropDownList(Window *w, DropDownList &&list, int selected, WidgetID button, uint width, DropDownOptions options, std::string * const persistent_filter_text)
{
  /* Handle the beep of the player's click. */
  SndClickBeep();
 
  /* Our parent's button widget is used to determine where to place the drop
   * down list window. */
  NWidgetCore *nwi = w->GetWidget<NWidgetCore>(button);
  Rect wi_rect      = nwi->GetCurrentRect();
  Colours wi_colour = nwi->colour;
 
  if ((nwi->type & WWT_MASK) == NWID_BUTTON_DROPDOWN) {
    nwi->disp_flags.Set(NWidgetDisplayFlag::DropdownActive);
  } else {
    nwi->SetLowered(true);
  }
  nwi->SetDirty(w);
 
  if (width != 0) {
    if (_current_text_dir == TD_RTL) {
      wi_rect.left = wi_rect.right + 1 - ScaleGUITrad(width);
    } else {
      wi_rect.right = wi_rect.left + ScaleGUITrad(width) - 1;
    }
  }
 
  ShowDropDownListAt(w, std::move(list), selected, button, wi_rect, wi_colour, options, persistent_filter_text);
}

void ShowDropDownMenu(Window *w, std::span<const StringID> strings, int selected, WidgetID button, uint32_t disabled_mask, uint32_t hidden_mask, uint width, DropDownOptions options, std::string * const persistent_filter_text)
{
  DropDownList list;
 
  uint i = 0;
  for (auto string : strings) {
    if (!HasBit(hidden_mask, i)) {
      list.push_back(MakeDropDownListStringItem(string, i, HasBit(disabled_mask, i)));
    }
    ++i;
  }
 
  if (!list.empty()) ShowDropDownList(w, std::move(list), selected, button, width, options, persistent_filter_text);
}