src/story_gui.cpp

   1 /* $Id: story_gui.cpp 26307 2014-02-06 19:50:34Z zuu $ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file story_gui.cpp GUI for stories. */
  11
  12 #include "stdafx.h"
  13 #include "window_gui.h"
  14 #include "strings_func.h"
  15 #include "date_func.h"
  16 #include "gui.h"
  17 #include "story_base.h"
  18 #include "core/geometry_func.hpp"
  19 #include "company_func.h"
  20 #include "command_func.h"
  21 #include "widgets/dropdown_type.h"
  22 #include "widgets/dropdown_func.h"
  23 #include "sortlist_type.h"
  24 #include "goal_base.h"
  25 #include "viewport_func.h"
  26 #include "window_func.h"
  27 #include "company_base.h"
  28
  29 #include "widgets/story_widget.h"
  30
  31 #include "table/strings.h"
  32 #include "table/sprites.h"
  33
  34 #include "safeguards.h"
  35
  36 typedef GUIList<const StoryPage*> GUIStoryPageList;
  37 typedef GUIList<const StoryPageElement*> GUIStoryPageElementList;
  38
  39 struct StoryBookWindow : Window {
  40 protected:
  41         Scrollbar *vscroll;                ///< Scrollbar of the page text.
  42
  43         GUIStoryPageList story_pages;      ///< Sorted list of pages.
  44         GUIStoryPageElementList story_page_elements; ///< Sorted list of page elements that belong to the current page.
  45         StoryPageID selected_page_id;      ///< Pool index of selected page.
  46         char selected_generic_title[255];  ///< If the selected page doesn't have a custom title, this buffer is used to store a generic page title.
  47
  48         static GUIStoryPageList::SortFunction * const page_sorter_funcs[];
  49         static GUIStoryPageElementList::SortFunction * const page_element_sorter_funcs[];
  50
  51         /** (Re)Build story page list. */
  52         void BuildStoryPageList()
  53         {
  54                 if (this->story_pages.NeedRebuild()) {
  55                         this->story_pages.Clear();
  56
  57                         const StoryPage *p;
  58                         FOR_ALL_STORY_PAGES(p) {
  59                                 if (this->IsPageAvailable(p)) {
  60                                         *this->story_pages.Append() = p;
  61                                 }
  62                         }
  63
  64                         this->story_pages.Compact();
  65                         this->story_pages.RebuildDone();
  66                 }
  67
  68                 this->story_pages.Sort();
  69         }
  70
  71         /** Sort story pages by order value. */
  72         static int CDECL PageOrderSorter(const StoryPage * const *a, const StoryPage * const *b)
  73         {
  74                 return (*a)->sort_value - (*b)->sort_value;
  75         }
  76
  77         /** (Re)Build story page element list. */
  78         void BuildStoryPageElementList()
  79         {
  80                 if (this->story_page_elements.NeedRebuild()) {
  81                         this->story_page_elements.Clear();
  82
  83                         const StoryPage *p = GetSelPage();
  84                         if (p != NULL) {
  85                                 const StoryPageElement *pe;
  86                                 FOR_ALL_STORY_PAGE_ELEMENTS(pe) {
  87                                         if (pe->page == p->index) {
  88                                                 *this->story_page_elements.Append() = pe;
  89                                         }
  90                                 }
  91                         }
  92
  93                         this->story_page_elements.Compact();
  94                         this->story_page_elements.RebuildDone();
  95                 }
  96
  97                 this->story_page_elements.Sort();
  98         }
  99
 100         /** Sort story page elements by order value. */
 101         static int CDECL PageElementOrderSorter(const StoryPageElement * const *a, const StoryPageElement * const *b)
 102         {
 103                 return (*a)->sort_value - (*b)->sort_value;
 104         }
 105
 106         /*
 107          * Checks if a given page should be visible in the story book.
 108          * @param page The page to check.
 109          * @return True if the page should be visible, otherwise false.
 110          */
 111         bool IsPageAvailable(const StoryPage *page) const
 112         {
 113                 return page->company == INVALID_COMPANY || page->company == this->window_number;
 114         }
 115
 116         /**
 117          * Get instance of selected page.
 118          * @return Instance of selected page or NULL if no page is selected.
 119          */
 120         StoryPage *GetSelPage() const
 121         {
 122                 if (!_story_page_pool.IsValidID(selected_page_id)) return NULL;
 123                 return _story_page_pool.Get(selected_page_id);
 124         }
 125
 126         /**
 127          * Get the page number of selected page.
 128          * @return Number of available pages before to the selected one, or -1 if no page is selected.
 129          */
 130         int GetSelPageNum() const
 131         {
 132                 int page_number = 0;
 133                 for (const StoryPage *const*iter = this->story_pages.Begin(); iter != this->story_pages.End(); iter++) {
 134                         const StoryPage *p = *iter;
 135                         if (p->index == this->selected_page_id) {
 136                                 return page_number;
 137                         }
 138                         page_number++;
 139                 }
 140                 return -1;
 141         }
 142
 143         /**
 144          * Check if the selected page is also the first available page.
 145          */
 146         bool IsFirstPageSelected()
 147         {
 148                 /* Verify that the selected page exist. */
 149                 if (!_story_page_pool.IsValidID(this->selected_page_id)) return false;
 150
 151                 return (*this->story_pages.Begin())->index == this->selected_page_id;
 152         }
 153
 154         /**
 155          * Check if the selected page is also the last available page.
 156          */
 157         bool IsLastPageSelected()
 158         {
 159                 /* Verify that the selected page exist. */
 160                 if (!_story_page_pool.IsValidID(this->selected_page_id)) return false;
 161
 162                 if (this->story_pages.Length() <= 1) return true;
 163                 const StoryPage *last = *(this->story_pages.End() - 1);
 164                 return last->index == this->selected_page_id;
 165         }
 166
 167         /**
 168          * Updates the content of selected page.
 169          */
 170         void RefreshSelectedPage()
 171         {
 172                 /* Generate generic title if selected page have no custom title. */
 173                 StoryPage *page = this->GetSelPage();
 174                 if (page != NULL && page->title == NULL) {
 175                         SetDParam(0, GetSelPageNum() + 1);
 176                         GetString(selected_generic_title, STR_STORY_BOOK_GENERIC_PAGE_ITEM, lastof(selected_generic_title));
 177                 }
 178
 179                 this->story_page_elements.ForceRebuild();
 180                 this->BuildStoryPageElementList();
 181
 182                 this->vscroll->SetCount(this->GetContentHeight());
 183                 this->SetWidgetDirty(WID_SB_SCROLLBAR);
 184                 this->SetWidgetDirty(WID_SB_SEL_PAGE);
 185                 this->SetWidgetDirty(WID_SB_PAGE_PANEL);
 186         }
 187
 188         /**
 189          * Selects the previous available page before the currently selected page.
 190          */
 191         void SelectPrevPage()
 192         {
 193                 if (!_story_page_pool.IsValidID(this->selected_page_id)) return;
 194
 195                 /* Find the last available page which is previous to the current selected page. */
 196                 const StoryPage *last_available;
 197                 last_available = NULL;
 198                 for (const StoryPage *const*iter = this->story_pages.Begin(); iter != this->story_pages.End(); iter++) {
 199                         const StoryPage *p = *iter;
 200                         if (p->index == this->selected_page_id) {
 201                                 if (last_available == NULL) return; // No previous page available.
 202                                 this->SetSelectedPage(last_available->index);
 203                                 return;
 204                         }
 205                         last_available = p;
 206                 }
 207         }
 208
 209         /**
 210          * Selects the next available page after the currently selected page.
 211          */
 212         void SelectNextPage()
 213         {
 214                 if (!_story_page_pool.IsValidID(this->selected_page_id)) return;
 215
 216                 /* Find selected page. */
 217                 for (const StoryPage *const*iter = this->story_pages.Begin(); iter != this->story_pages.End(); iter++) {
 218                         const StoryPage *p = *iter;
 219                         if (p->index == this->selected_page_id) {
 220                                 /* Select the page after selected page. */
 221                                 iter++;
 222                                 if (iter != this->story_pages.End()) {
 223                                         this->SetSelectedPage((*iter)->index);
 224                                 }
 225                                 return;
 226                         }
 227                 }
 228         }
 229
 230         /**
 231          * Builds the page selector drop down list.
 232          */
 233         DropDownList *BuildDropDownList() const
 234         {
 235                 DropDownList *list = new DropDownList();
 236                 uint16 page_num = 1;
 237                 for (const StoryPage *const*iter = this->story_pages.Begin(); iter != this->story_pages.End(); iter++) {
 238                         const StoryPage *p = *iter;
 239                         bool current_page = p->index == this->selected_page_id;
 240                         DropDownListStringItem *item = NULL;
 241                         if (p->title != NULL) {
 242                                 item = new DropDownListCharStringItem(p->title, p->index, current_page);
 243                         } else {
 244                                 /* No custom title => use a generic page title with page number. */
 245                                 DropDownListParamStringItem *str_item =
 246                                                 new DropDownListParamStringItem(STR_STORY_BOOK_GENERIC_PAGE_ITEM, p->index, current_page);
 247                                 str_item->SetParam(0, page_num);
 248                                 item = str_item;
 249                         }
 250
 251                         *list->Append() = item;
 252                         page_num++;
 253                 }
 254
 255                 /* Check if list is empty. */
 256                 if (list->Length() == 0) {
 257                         delete list;
 258                         list = NULL;
 259                 }
 260
 261                 return list;
 262         }
 263
 264         /**
 265          * Get the width available for displaying content on the page panel.
 266          */
 267         uint GetAvailablePageContentWidth()
 268         {
 269                 return this->GetWidget<NWidgetCore>(WID_SB_PAGE_PANEL)->current_x - WD_FRAMETEXT_LEFT - WD_FRAMERECT_RIGHT;
 270         }
 271
 272         /**
 273          * Counts how many pixels of height that are used by Date and Title
 274          * (excluding marginal after Title, as each body element has
 275          * an empty row before the elment).
 276          * @param max_width Available width to display content.
 277          * @return the height in pixels.
 278          */
 279         uint GetHeadHeight(int max_width) const
 280         {
 281                 StoryPage *page = this->GetSelPage();
 282                 if (page == NULL) return 0;
 283                 int height = 0;
 284
 285                 /* Title lines */
 286                 height += FONT_HEIGHT_NORMAL; // Date always use exactly one line.
 287                 SetDParamStr(0, page->title != NULL ? page->title : this->selected_generic_title);
 288                 height += GetStringHeight(STR_STORY_BOOK_TITLE, max_width);
 289
 290                 return height;
 291         }
 292
 293         /**
 294          * Decides which sprite to display for a given page element.
 295          * @param pe The page element.
 296          * @return The SpriteID of the sprite to display.
 297          * @pre pe.type must be SPET_GOAL or SPET_LOCATION.
 298          */
 299         SpriteID GetPageElementSprite(const StoryPageElement &pe) const
 300         {
 301                 switch (pe.type) {
 302                         case SPET_GOAL: {
 303                                 Goal *g = Goal::Get((GoalID) pe.referenced_id);
 304                                 if (g == NULL) return SPR_IMG_GOAL_BROKEN_REF;
 305                                 return g->completed ? SPR_IMG_GOAL_COMPLETED : SPR_IMG_GOAL;
 306                         }
 307                         case SPET_LOCATION:
 308                                 return SPR_IMG_VIEW_LOCATION;
 309                         default:
 310                                 NOT_REACHED();
 311                 }
 312         }
 313
 314         /**
 315          * Get the height in pixels used by a page element.
 316          * @param pe The story page element.
 317          * @param max_width Available width to display content.
 318          * @return the height in pixels.
 319          */
 320         uint GetPageElementHeight(const StoryPageElement &pe, int max_width)
 321         {
 322                 switch (pe.type) {
 323                         case SPET_TEXT:
 324                                 SetDParamStr(0, pe.text);
 325                                 return GetStringHeight(STR_BLACK_RAW_STRING, max_width);
 326                                 break;
 327
 328                         case SPET_GOAL:
 329                         case SPET_LOCATION: {
 330                                 Dimension sprite_dim = GetSpriteSize(GetPageElementSprite(pe));
 331                                 return sprite_dim.height;
 332                                 break;
 333                         }
 334                         default:
 335                                 NOT_REACHED();
 336                 }
 337                 return 0;
 338         }
 339
 340         /**
 341          * Get the total height of the content displayed
 342          * in this window.
 343          * @return the height in pixels
 344          */
 345         uint GetContentHeight()
 346         {
 347                 StoryPage *page = this->GetSelPage();
 348                 if (page == NULL) return 0;
 349                 int max_width = GetAvailablePageContentWidth();
 350                 uint element_vertical_dist = FONT_HEIGHT_NORMAL;
 351
 352                 /* Head */
 353                 uint height = GetHeadHeight(max_width);
 354
 355                 /* Body */
 356                 for (const StoryPageElement **iter = this->story_page_elements.Begin(); iter != this->story_page_elements.End(); iter++) {
 357                         const StoryPageElement *pe = *iter;
 358                         height += element_vertical_dist;
 359                         height += GetPageElementHeight(*pe, max_width);
 360                 }
 361
 362                 return height;
 363         }
 364
 365         /**
 366          * Draws a page element that is composed of a sprite to the left and a single line of
 367          * text after that. These page elements are generally clickable and are thus called
 368          * action elements.
 369          * @param y_offset Current y_offset which will get updated when this method has completed its drawing.
 370          * @param width Width of the region available for drawing.
 371          * @param line_height Height of one line of text.
 372          * @param action_sprite The sprite to draw.
 373          * @param string_id The string id to draw.
 374          * @return the number of lines.
 375          */
 376         void DrawActionElement(int &y_offset, int width, int line_height, SpriteID action_sprite, StringID string_id = STR_JUST_RAW_STRING) const
 377         {
 378                 Dimension sprite_dim = GetSpriteSize(action_sprite);
 379                 uint element_height = max(sprite_dim.height, (uint)line_height);
 380
 381                 uint sprite_top = y_offset + (element_height - sprite_dim.height) / 2;
 382                 uint text_top = y_offset + (element_height - line_height) / 2;
 383
 384                 DrawSprite(action_sprite, PAL_NONE, 0, sprite_top);
 385                 DrawString(sprite_dim.width + WD_FRAMETEXT_LEFT, width, text_top, string_id, TC_BLACK);
 386
 387                 y_offset += element_height;
 388         }
 389
 390         /**
 391          * Internal event handler for when a page element is clicked.
 392          * @param pe The clicked page element.
 393          */
 394         void OnPageElementClick(const StoryPageElement& pe)
 395         {
 396                 switch (pe.type) {
 397                         case SPET_TEXT:
 398                                 /* Do nothing. */
 399                                 break;
 400
 401                         case SPET_LOCATION:
 402                                 if (_ctrl_pressed) {
 403                                         ShowExtraViewPortWindow((TileIndex)pe.referenced_id);
 404                                 } else {
 405                                         ScrollMainWindowToTile((TileIndex)pe.referenced_id);
 406                                 }
 407                                 break;
 408
 409                         case SPET_GOAL:
 410                                 ShowGoalsList((CompanyID)this->window_number);
 411                                 break;
 412
 413                         default:
 414                                 NOT_REACHED();
 415                 }
 416         }
 417
 418 public:
 419         StoryBookWindow(WindowDesc *desc, WindowNumber window_number) : Window(desc)
 420         {
 421                 this->CreateNestedTree();
 422                 this->vscroll = this->GetScrollbar(WID_SB_SCROLLBAR);
 423                 this->vscroll->SetStepSize(FONT_HEIGHT_NORMAL);
 424
 425                 /* Initalize page sort. */
 426                 this->story_pages.SetSortFuncs(StoryBookWindow::page_sorter_funcs);
 427                 this->story_pages.ForceRebuild();
 428                 this->BuildStoryPageList();
 429                 this->story_page_elements.SetSortFuncs(StoryBookWindow::page_element_sorter_funcs);
 430                 /* story_page_elements will get built by SetSelectedPage */
 431
 432                 this->FinishInitNested(window_number);
 433                 this->owner = (Owner)this->window_number;
 434
 435                 /* Initialize selected vars. */
 436                 this->selected_generic_title[0] = '\0';
 437                 this->selected_page_id = INVALID_STORY_PAGE;
 438
 439                 this->OnInvalidateData(-1);
 440         }
 441
 442         /**
 443          * Updates the disabled state of the prev/next buttons.
 444          */
 445         void UpdatePrevNextDisabledState()
 446         {
 447                 this->SetWidgetDisabledState(WID_SB_PREV_PAGE, story_pages.Length() == 0 || this->IsFirstPageSelected());
 448                 this->SetWidgetDisabledState(WID_SB_NEXT_PAGE, story_pages.Length() == 0 || this->IsLastPageSelected());
 449                 this->SetWidgetDirty(WID_SB_PREV_PAGE);
 450                 this->SetWidgetDirty(WID_SB_NEXT_PAGE);
 451         }
 452
 453         /**
 454          * Sets the selected page.
 455          * @param page_index pool index of the page to select.
 456          */
 457         void SetSelectedPage(uint16 page_index)
 458         {
 459                 if (this->selected_page_id != page_index) {
 460                         this->selected_page_id = page_index;
 461                         this->RefreshSelectedPage();
 462                         this->UpdatePrevNextDisabledState();
 463                 }
 464         }
 465
 466         virtual void SetStringParameters(int widget) const
 467         {
 468                 switch (widget) {
 469                         case WID_SB_SEL_PAGE: {
 470                                 StoryPage *page = this->GetSelPage();
 471                                 SetDParamStr(0, page != NULL && page->title != NULL ? page->title : this->selected_generic_title);
 472                                 break;
 473                         }
 474                         case WID_SB_CAPTION:
 475                                 if (this->window_number == INVALID_COMPANY) {
 476                                         SetDParam(0, STR_STORY_BOOK_SPECTATOR_CAPTION);
 477                                 } else {
 478                                         SetDParam(0, STR_STORY_BOOK_CAPTION);
 479                                         SetDParam(1, this->window_number);
 480                                 }
 481                                 break;
 482                 }
 483         }
 484
 485         virtual void OnPaint()
 486         {
 487                 /* Detect if content has changed height. This can happen if a
 488                  * multi-line text contains eg. {COMPANY} and that company is
 489                  * renamed.
 490                  */
 491                 if (this->vscroll->GetCount() != this->GetContentHeight()) {
 492                         this->vscroll->SetCount(this->GetContentHeight());
 493                         this->SetWidgetDirty(WID_SB_SCROLLBAR);
 494                         this->SetWidgetDirty(WID_SB_PAGE_PANEL);
 495                 }
 496
 497                 this->DrawWidgets();
 498         }
 499
 500         virtual void DrawWidget(const Rect &r, int widget) const
 501         {
 502                 if (widget != WID_SB_PAGE_PANEL) return;
 503
 504                 StoryPage *page = this->GetSelPage();
 505                 if (page == NULL) return;
 506
 507                 const int x = r.left + WD_FRAMETEXT_LEFT;
 508                 const int y = r.top + WD_FRAMETEXT_TOP;
 509                 const int right = r.right - WD_FRAMETEXT_RIGHT;
 510                 const int bottom = r.bottom - WD_FRAMETEXT_BOTTOM;
 511
 512                 /* Set up a clipping region for the panel. */
 513                 DrawPixelInfo tmp_dpi;
 514                 if (!FillDrawPixelInfo(&tmp_dpi, x, y, right - x + 1, bottom - y + 1)) return;
 515
 516                 DrawPixelInfo *old_dpi = _cur_dpi;
 517                 _cur_dpi = &tmp_dpi;
 518
 519                 /* Draw content (now coordinates given to Draw** are local to the new clipping region). */
 520                 int line_height = FONT_HEIGHT_NORMAL;
 521                 int y_offset = - this->vscroll->GetPosition();
 522
 523                 /* Date */
 524                 if (page->date != INVALID_DATE) {
 525                         SetDParam(0, page->date);
 526                         DrawString(0, right - x, y_offset, STR_JUST_DATE_LONG, TC_BLACK);
 527                 }
 528                 y_offset += line_height;
 529
 530                 /* Title */
 531                 SetDParamStr(0, page->title != NULL ? page->title : this->selected_generic_title);
 532                 y_offset = DrawStringMultiLine(0, right - x, y_offset, bottom - y, STR_STORY_BOOK_TITLE, TC_BLACK, SA_TOP | SA_HOR_CENTER);
 533
 534                 /* Page elements */
 535                 for (const StoryPageElement *const*iter = this->story_page_elements.Begin(); iter != this->story_page_elements.End(); iter++) {
 536                         const StoryPageElement *const pe = *iter;
 537                         y_offset += line_height; // margin to previous element
 538
 539                         switch (pe->type) {
 540                                 case SPET_TEXT:
 541                                         SetDParamStr(0, pe->text);
 542                                         y_offset = DrawStringMultiLine(0, right - x, y_offset, bottom - y, STR_JUST_RAW_STRING, TC_BLACK, SA_TOP | SA_LEFT);
 543                                         break;
 544
 545                                 case SPET_GOAL: {
 546                                         Goal *g = Goal::Get((GoalID) pe->referenced_id);
 547                                         StringID string_id = g == NULL ? STR_STORY_BOOK_INVALID_GOAL_REF : STR_JUST_RAW_STRING;
 548                                         if (g != NULL) SetDParamStr(0, g->text);
 549                                         DrawActionElement(y_offset, right - x, line_height, GetPageElementSprite(*pe), string_id);
 550                                         break;
 551                                 }
 552
 553                                 case SPET_LOCATION:
 554                                         SetDParamStr(0, pe->text);
 555                                         DrawActionElement(y_offset, right - x, line_height, GetPageElementSprite(*pe));
 556                                         break;
 557
 558                                 default: NOT_REACHED();
 559                         }
 560                 }
 561
 562                 /* Restore clipping region. */
 563                 _cur_dpi = old_dpi;
 564         }
 565
 566         virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
 567         {
 568                 if (widget != WID_SB_SEL_PAGE && widget != WID_SB_PAGE_PANEL) return;
 569
 570                 Dimension d;
 571                 d.height = FONT_HEIGHT_NORMAL;
 572                 d.width = 0;
 573
 574                 switch (widget) {
 575                         case WID_SB_SEL_PAGE: {
 576
 577                                 /* Get max title width. */
 578                                 for (uint16 i = 0; i < this->story_pages.Length(); i++) {
 579                                         const StoryPage *s = this->story_pages[i];
 580
 581                                         if (s->title != NULL) {
 582                                                 SetDParamStr(0, s->title);
 583                                         } else {
 584                                                 SetDParamStr(0, this->selected_generic_title);
 585                                         }
 586                                         Dimension title_d = GetStringBoundingBox(STR_BLACK_RAW_STRING);
 587
 588                                         if (title_d.width > d.width) {
 589                                                 d.width = title_d.width;
 590                                         }
 591                                 }
 592
 593                                 d.width += padding.width;
 594                                 d.height += padding.height;
 595                                 *size = maxdim(*size, d);
 596                                 break;
 597                         }
 598
 599                         case WID_SB_PAGE_PANEL: {
 600                                 d.height *= 5;
 601                                 d.height += padding.height + WD_FRAMETEXT_TOP + WD_FRAMETEXT_BOTTOM;
 602                                 *size = maxdim(*size, d);
 603                                 break;
 604                         }
 605                 }
 606
 607         }
 608
 609         virtual void OnResize()
 610         {
 611                 this->vscroll->SetCapacityFromWidget(this, WID_SB_PAGE_PANEL, WD_FRAMETEXT_TOP + WD_FRAMETEXT_BOTTOM);
 612                 this->vscroll->SetCount(this->GetContentHeight());
 613         }
 614
 615         virtual void OnClick(Point pt, int widget, int click_count)
 616         {
 617                 switch (widget) {
 618                         case WID_SB_SEL_PAGE: {
 619                                 DropDownList *list = this->BuildDropDownList();
 620                                 if (list != NULL) {
 621                                         /* Get the index of selected page. */
 622                                         int selected = 0;
 623                                         for (uint16 i = 0; i < this->story_pages.Length(); i++) {
 624                                                 const StoryPage *p = this->story_pages[i];
 625                                                 if (p->index == this->selected_page_id) break;
 626                                                 selected++;
 627                                         }
 628
 629                                         ShowDropDownList(this, list, selected, widget);
 630                                 }
 631                                 break;
 632                         }
 633
 634                         case WID_SB_PREV_PAGE:
 635                                 this->SelectPrevPage();
 636                                 break;
 637
 638                         case WID_SB_NEXT_PAGE:
 639                                 this->SelectNextPage();
 640                                 break;
 641
 642                         case WID_SB_PAGE_PANEL: {
 643                                 uint clicked_y = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_SB_PAGE_PANEL, WD_FRAMETEXT_TOP);
 644                                 uint max_width = GetAvailablePageContentWidth();
 645
 646                                 /* Skip head rows. */
 647                                 uint head_height = this->GetHeadHeight(max_width);
 648                                 if (clicked_y < head_height) return;
 649
 650                                 /* Detect if a page element was clicked. */
 651                                 uint y = head_height;
 652                                 uint element_vertical_dist = FONT_HEIGHT_NORMAL;
 653                                 for (const StoryPageElement *const*iter = this->story_page_elements.Begin(); iter != this->story_page_elements.End(); iter++) {
 654                                         const StoryPageElement *const pe = *iter;
 655
 656                                         y += element_vertical_dist; // margin row
 657
 658                                         uint content_height = GetPageElementHeight(*pe, max_width);
 659                                         if (clicked_y >= y && clicked_y < y + content_height) {
 660                                                 this->OnPageElementClick(*pe);
 661                                                 return;
 662                                         }
 663
 664                                         y += content_height;
 665                                 }
 666                         }
 667                 }
 668         }
 669
 670         virtual void OnDropdownSelect(int widget, int index)
 671         {
 672                 if (widget != WID_SB_SEL_PAGE) return;
 673
 674                 /* index (which is set in BuildDropDownList) is the page id. */
 675                 this->SetSelectedPage(index);
 676         }
 677
 678         /**
 679          * Some data on this window has become invalid.
 680          * @param data Information about the changed data.
 681          *   -1     Rebuild page list and refresh current page;
 682          *   >= 0   Id of the page that needs to be refreshed. If it is not the current page, nothing happens.
 683          * @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.
 684          */
 685         virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 686         {
 687                 if (!gui_scope) return;
 688
 689                 /* If added/removed page, force rebuild. Sort order never change so just a
 690                  * re-sort is never needed.
 691                  */
 692                 if (data == -1) {
 693                         this->story_pages.ForceRebuild();
 694                         this->BuildStoryPageList();
 695
 696                         /* Was the last page removed? */
 697                         if (this->story_pages.Length() == 0) {
 698                                 this->selected_generic_title[0] = '\0';
 699                         }
 700
 701                         /* Verify page selection. */
 702                         if (!_story_page_pool.IsValidID(this->selected_page_id)) {
 703                                 this->selected_page_id = INVALID_STORY_PAGE;
 704                         }
 705                         if (this->selected_page_id == INVALID_STORY_PAGE && this->story_pages.Length() > 0) {
 706                                 /* No page is selected, but there exist at least one available.
 707                                  * => Select first page.
 708                                  */
 709                                 this->SetSelectedPage(this->story_pages[0]->index);
 710                         }
 711
 712                         this->SetWidgetDisabledState(WID_SB_SEL_PAGE, this->story_pages.Length() == 0);
 713                         this->SetWidgetDirty(WID_SB_SEL_PAGE);
 714                         this->UpdatePrevNextDisabledState();
 715                 } else if (data >= 0 && this->selected_page_id == data) {
 716                         this->RefreshSelectedPage();
 717                 }
 718         }
 719 };
 720
 721 GUIStoryPageList::SortFunction * const StoryBookWindow::page_sorter_funcs[] = {
 722         &PageOrderSorter,
 723 };
 724
 725 GUIStoryPageElementList::SortFunction * const StoryBookWindow::page_element_sorter_funcs[] = {
 726         &PageElementOrderSorter,
 727 };
 728
 729 static const NWidgetPart _nested_story_book_widgets[] = {
 730         NWidget(NWID_HORIZONTAL),
 731                 NWidget(WWT_CLOSEBOX, COLOUR_BROWN),
 732                 NWidget(WWT_CAPTION, COLOUR_BROWN, WID_SB_CAPTION), SetDataTip(STR_JUST_STRING, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 733                 NWidget(WWT_SHADEBOX, COLOUR_BROWN),
 734                 NWidget(WWT_DEFSIZEBOX, COLOUR_BROWN),
 735                 NWidget(WWT_STICKYBOX, COLOUR_BROWN),
 736         EndContainer(),
 737         NWidget(NWID_HORIZONTAL), SetFill(1, 1),
 738                 NWidget(NWID_VERTICAL), SetFill(1, 1),
 739                         NWidget(WWT_PANEL, COLOUR_BROWN, WID_SB_PAGE_PANEL), SetResize(1, 1), SetScrollbar(WID_SB_SCROLLBAR), EndContainer(),
 740                         NWidget(NWID_HORIZONTAL),
 741                                 NWidget(WWT_TEXTBTN, COLOUR_BROWN, WID_SB_PREV_PAGE), SetMinimalSize(100, 0), SetFill(0, 0), SetDataTip(STR_STORY_BOOK_PREV_PAGE, STR_STORY_BOOK_PREV_PAGE_TOOLTIP),
 742                                 NWidget(NWID_BUTTON_DROPDOWN, COLOUR_BROWN, WID_SB_SEL_PAGE), SetMinimalSize(93, 12), SetFill(1, 0),
 743                                                                                                                 SetDataTip(STR_BLACK_RAW_STRING, STR_STORY_BOOK_SEL_PAGE_TOOLTIP), SetResize(1, 0),
 744                                 NWidget(WWT_TEXTBTN, COLOUR_BROWN, WID_SB_NEXT_PAGE), SetMinimalSize(100, 0), SetFill(0, 0), SetDataTip(STR_STORY_BOOK_NEXT_PAGE, STR_STORY_BOOK_NEXT_PAGE_TOOLTIP),
 745                         EndContainer(),
 746                 EndContainer(),
 747                 NWidget(NWID_VERTICAL), SetFill(0, 1),
 748                         NWidget(NWID_VSCROLLBAR, COLOUR_BROWN, WID_SB_SCROLLBAR),
 749                         NWidget(WWT_RESIZEBOX, COLOUR_BROWN),
 750                 EndContainer(),
 751         EndContainer(),
 752 };
 753
 754 static WindowDesc _story_book_desc(
 755         WDP_CENTER, "view_story", 400, 300,
 756         WC_STORY_BOOK, WC_NONE,
 757         0,
 758         _nested_story_book_widgets, lengthof(_nested_story_book_widgets)
 759 );
 760
 761 /**
 762  * Raise or create the story book window for \a company, at page \a page_id.
 763  * @param company 'Owner' of the story book, may be #INVALID_COMPANY.
 764  * @param page_id Page to open, may be #INVALID_STORY_PAGE.
 765  */
 766 void ShowStoryBook(CompanyID company, uint16 page_id)
 767 {
 768         if (!Company::IsValidID(company)) company = (CompanyID)INVALID_COMPANY;
 769
 770         StoryBookWindow *w = AllocateWindowDescFront<StoryBookWindow>(&_story_book_desc, company, true);
 771         if (page_id != INVALID_STORY_PAGE) w->SetSelectedPage(page_id);
 772 }