webdvd.cpp

   1 // Copyright 2005 Ben Hutchings <ben@decadentplace.org.uk>.
   2 // See the file "COPYING" for licence details.
   3
   4 #include <cassert>
   5 #include <exception>
   6 #include <fstream>
   7 #include <iomanip>
   8 #include <iostream>
   9 #include <memory>
  10 #include <queue>
  11 #include <set>
  12 #include <sstream>
  13 #include <string>
  14
  15 #include <stdlib.h>
  16 #include <unistd.h>
  17
  18 #include <boost/shared_ptr.hpp>
  19
  20 #include <gdkmm/pixbuf.h>
  21 #include <glibmm/convert.h>
  22 #include <glibmm/spawn.h>
  23 #include <gtkmm/main.h>
  24 #include <gtkmm/window.h>
  25
  26 #include <imglib2/ImageErrors.h>
  27 #include <nsGUIEvent.h>
  28 #include <nsIBoxObject.h>
  29 #include <nsIContent.h>
  30 #include <nsIDocShell.h>
  31 #include <nsIDOMAbstractView.h>
  32 #include <nsIDOMDocumentEvent.h>
  33 #include <nsIDOMDocumentView.h>
  34 #include <nsIDOMElement.h>
  35 #include <nsIDOMEventTarget.h>
  36 #include <nsIDOMHTMLDocument.h>
  37 #include <nsIDOMMouseEvent.h>
  38 #include <nsIDOMNSDocument.h>
  39 #include <nsIDOMWindow.h>
  40 #include <nsIEventStateManager.h>
  41 #include <nsIInterfaceRequestorUtils.h>
  42 #include <nsIURI.h> // required before nsILink.h
  43 #include <nsILink.h>
  44 #include <nsIPresContext.h>
  45 #include <nsIPresShell.h>
  46 #include <nsIWebBrowser.h>
  47 #include <nsString.h>
  48
  49 #include "browserwidget.hpp"
  50 #include "childiterator.hpp"
  51 #include "dvd.hpp"
  52 #include "framebuffer.hpp"
  53 #include "linkiterator.hpp"
  54 #include "pixbufs.hpp"
  55 #include "stylesheets.hpp"
  56 #include "temp_file.hpp"
  57 #include "video.hpp"
  58 #include "xpcom_support.hpp"
  59
  60 using xpcom_support::check;
  61
  62 namespace
  63 {
  64     struct rectangle
  65     {
  66         int left, top;     // inclusive
  67         int right, bottom; // exclusive
  68
  69         rectangle operator|=(const rectangle & other)
  70             {
  71                 if (other.empty())
  72                 {
  73                     // use current extents unchanged
  74                 }
  75                 else if (empty())
  76                 {
  77                     // use other extents
  78                     *this = other;
  79                 }
  80                 else
  81                 {
  82                     // find rectangle enclosing both extents
  83                     left = std::min(left, other.left);
  84                     top = std::min(top, other.top);
  85                     right = std::max(right, other.right);
  86                     bottom = std::max(bottom, other.bottom);
  87                 }
  88
  89                 return *this;
  90             }
  91
  92         rectangle operator&=(const rectangle & other)
  93             {
  94                 // find rectangle enclosed in both extents
  95                 left = std::max(left, other.left);
  96                 top = std::max(top, other.top);
  97                 right = std::max(left, std::min(right, other.right));
  98                 bottom = std::max(top, std::min(bottom, other.bottom));
  99                 return *this;
 100             }
 101
 102         bool empty() const
 103             {
 104                 return left == right || bottom == top;
 105             }
 106     };
 107
 108     rectangle get_elem_rect(nsIDOMNSDocument * ns_doc,
 109                             nsIDOMElement * elem)
 110     {
 111         rectangle result;
 112
 113         // Start with this element's bounding box
 114         nsCOMPtr<nsIBoxObject> box;
 115         check(ns_doc->GetBoxObjectFor(elem, getter_AddRefs(box)));
 116         int width, height;
 117         check(box->GetScreenX(&result.left));
 118         check(box->GetScreenY(&result.top));
 119         check(box->GetWidth(&width));
 120         check(box->GetHeight(&height));
 121         result.right = result.left + width;
 122         result.bottom = result.top + height;
 123
 124         // Merge bounding boxes of all child elements
 125         for (ChildIterator it = ChildIterator(elem), end; it != end; ++it)
 126         {
 127             nsCOMPtr<nsIDOMNode> child_node(*it);
 128             PRUint16 child_type;
 129             if (check(child_node->GetNodeType(&child_type)),
 130                 child_type == nsIDOMNode::ELEMENT_NODE)
 131             {
 132                 nsCOMPtr<nsIDOMElement> child_elem(
 133                     do_QueryInterface(child_node));
 134                 result |= get_elem_rect(ns_doc, child_elem);
 135             }
 136         }
 137
 138         return result;
 139     }
 140
 141     class WebDvdWindow : public Gtk::Window
 142     {
 143     public:
 144         WebDvdWindow(
 145             const video::frame_params & frame_params,
 146             const std::string & main_page_uri,
 147             const std::string & output_dir);
 148
 149     private:
 150         void add_page(const std::string & uri);
 151         void add_video(const std::string & uri);
 152         void load_next_page();
 153         void on_net_state_change(const char * uri, gint flags, guint status);
 154         bool process_page();
 155         void save_screenshot();
 156         void process_links(nsIPresShell * pres_shell,
 157                            nsIPresContext * pres_context,
 158                            nsIDOMWindow * dom_window);
 159         void generate_dvd();
 160
 161         enum ResourceType { page_resource, video_resource };
 162         typedef std::pair<ResourceType, int> ResourceEntry;
 163         video::frame_params frame_params_;
 164         std::string output_dir_;
 165         BrowserWidget browser_widget_;
 166         nsCOMPtr<nsIStyleSheet> stylesheet_;
 167         std::queue<std::string> page_queue_;
 168         std::map<std::string, ResourceEntry> resource_map_;
 169         std::vector<std::vector<std::string> > page_links_;
 170         std::vector<std::string> video_paths_;
 171         bool pending_window_update_;
 172         int pending_req_count_;
 173         std::auto_ptr<temp_file> background_temp_;
 174         struct page_state;
 175         std::auto_ptr<page_state> page_state_;
 176         std::vector<boost::shared_ptr<temp_file> > page_temp_files_;
 177     };
 178
 179     WebDvdWindow::WebDvdWindow(
 180         const video::frame_params & frame_params,
 181         const std::string & main_page_uri,
 182         const std::string & output_dir)
 183             : frame_params_(frame_params),
 184               output_dir_(output_dir),
 185               stylesheet_(load_css("file://" WEBDVD_LIB_DIR "/webdvd.css")),
 186               pending_window_update_(false),
 187               pending_req_count_(0)
 188     {
 189         set_default_size(frame_params_.width, frame_params_.height);
 190         add(browser_widget_);
 191         browser_widget_.show();
 192         browser_widget_.signal_net_state().connect(
 193             SigC::slot(*this, &WebDvdWindow::on_net_state_change));
 194
 195         add_page(main_page_uri);
 196         load_next_page();
 197     }
 198
 199     void WebDvdWindow::add_page(const std::string & uri)
 200     {
 201         if (resource_map_.insert(
 202                 std::make_pair(uri, ResourceEntry(page_resource, 0)))
 203             .second)
 204         {
 205             page_queue_.push(uri);
 206         }
 207     }
 208
 209     void WebDvdWindow::add_video(const std::string & uri)
 210     {
 211         if (resource_map_.insert(
 212                 std::make_pair(uri, ResourceEntry(video_resource,
 213                                                   video_paths_.size() + 1)))
 214             .second)
 215         {
 216             // FIXME: Should accept some slightly different URI prefixes
 217             // (e.g. file://localhost/) and decode any URI-escaped
 218             // characters in the path.
 219             assert(uri.compare(0, 8, "file:///") == 0);
 220             video_paths_.push_back(uri.substr(7));
 221         }
 222     }
 223
 224     void WebDvdWindow::load_next_page()
 225     {
 226         assert(!page_queue_.empty());
 227         const std::string & uri = page_queue_.front();
 228         std::cout << "loading " << uri << std::endl;
 229
 230         std::size_t page_count = page_links_.size();
 231         resource_map_[uri].second = ++page_count;
 232         page_links_.resize(page_count);
 233
 234         pending_window_update_ = true;
 235         browser_widget_.load_uri(uri);
 236     }
 237
 238     void WebDvdWindow::on_net_state_change(const char * uri,
 239                                            gint flags, guint status)
 240     {
 241         if (flags & GTK_MOZ_EMBED_FLAG_IS_REQUEST)
 242         {
 243             if (flags & GTK_MOZ_EMBED_FLAG_START)
 244                 ++pending_req_count_;
 245
 246             if (flags & GTK_MOZ_EMBED_FLAG_STOP)
 247             {
 248                 assert(pending_req_count_ != 0);
 249                 --pending_req_count_;
 250             }
 251         }
 252
 253         if (flags & GTK_MOZ_EMBED_FLAG_STOP
 254             && flags & GTK_MOZ_EMBED_FLAG_IS_WINDOW)
 255         {
 256             // Check whether the load was successful, ignoring this
 257             // pseudo-error.
 258             if (status != NS_IMAGELIB_ERROR_LOAD_ABORTED)
 259                 check(status);
 260
 261             pending_window_update_ = false;
 262         }
 263
 264         if (pending_req_count_ == 0 && !pending_window_update_)
 265         {
 266             try
 267             {
 268                 if (!process_page())
 269                     Gtk::Main::quit();
 270             }
 271             catch (std::exception & e)
 272             {
 273                 std::cerr << "Fatal error";
 274                 if (!page_queue_.empty())
 275                     std::cerr << " while processing <" << page_queue_.front()
 276                               << ">";
 277                 std::cerr << ": " << e.what() << "\n";
 278                 Gtk::Main::quit();
 279             }
 280         }
 281     }
 282
 283     bool WebDvdWindow::process_page()
 284     {
 285         assert(!page_queue_.empty());
 286
 287         nsCOMPtr<nsIWebBrowser> browser(browser_widget_.get_browser());
 288         nsCOMPtr<nsIDocShell> doc_shell(do_GetInterface(browser));
 289         assert(doc_shell);
 290         nsCOMPtr<nsIPresShell> pres_shell;
 291         check(doc_shell->GetPresShell(getter_AddRefs(pres_shell)));
 292         nsCOMPtr<nsIPresContext> pres_context;
 293         check(doc_shell->GetPresContext(getter_AddRefs(pres_context)));
 294         nsCOMPtr<nsIDOMWindow> dom_window;
 295         check(browser->GetContentDOMWindow(getter_AddRefs(dom_window)));
 296
 297         if (output_dir_.empty())
 298         {
 299             // In preview mode, just apply the stylesheet and let the
 300             // user select links.
 301             apply_style_sheet(stylesheet_, pres_shell);
 302         }
 303         else
 304         {
 305             // If we haven't already started work on this page, apply
 306             // the stylesheet and save a screenshot of its normal
 307             // appearance.
 308             if (!page_state_.get())
 309             {
 310                 apply_style_sheet(stylesheet_, pres_shell);
 311                 save_screenshot();
 312             }
 313
 314             // Start or continue processing links.
 315             process_links(pres_shell, pres_context, dom_window);
 316
 317             // If we've finished work on the links, move on to the
 318             // next page, if any, or else generate the DVD filesystem.
 319             if (!page_state_.get())
 320             {
 321                 page_queue_.pop();
 322                 if (page_queue_.empty())
 323                 {
 324                     generate_dvd();
 325                     return false;
 326                 }
 327                 else
 328                 {
 329                     load_next_page();
 330                 }
 331             }
 332         }
 333
 334         return true;
 335     }
 336
 337     void WebDvdWindow::save_screenshot()
 338     {
 339         Glib::RefPtr<Gdk::Window> window(get_window());
 340         assert(window);
 341         window->process_updates(true);
 342
 343         background_temp_.reset(new temp_file("webdvd-back-"));
 344         background_temp_->close();
 345         std::cout << "saving " << background_temp_->get_name() << std::endl;
 346         Gdk::Pixbuf::create(Glib::RefPtr<Gdk::Drawable>(window),
 347                             window->get_colormap(),
 348                             0, 0, 0, 0,
 349                             frame_params_.width, frame_params_.height)
 350             ->save(background_temp_->get_name(), "png");
 351     }
 352
 353     struct WebDvdWindow::page_state
 354     {
 355         page_state(nsIDOMDocument * doc, int width, int height)
 356                 : diff_pixbuf(Gdk::Pixbuf::create(
 357                                   Gdk::COLORSPACE_RGB,
 358                                   true, 8, // has_alpha, bits_per_sample
 359                                   width, height)),
 360                   spumux_temp("webdvd-spumux-"),
 361                   links_temp("webdvd-links-"),
 362                   link_num(0),
 363                   links_it(doc),
 364                   link_changing(false)
 365             {
 366                 spumux_temp.close();
 367                 links_temp.close();
 368             }
 369
 370         Glib::RefPtr<Gdk::Pixbuf> diff_pixbuf;
 371
 372         temp_file spumux_temp;
 373         std::ofstream spumux_file;
 374
 375         temp_file links_temp;
 376
 377         int link_num;
 378         LinkIterator links_it, links_end;
 379
 380         rectangle link_rect;
 381         bool link_changing;
 382         Glib::RefPtr<Gdk::Pixbuf> norm_pixbuf;
 383     };
 384
 385     void WebDvdWindow::process_links(nsIPresShell * pres_shell,
 386                                      nsIPresContext * pres_context,
 387                                      nsIDOMWindow * dom_window)
 388     {
 389         Glib::RefPtr<Gdk::Window> window(get_window());
 390         assert(window);
 391
 392         nsCOMPtr<nsIDOMDocument> basic_doc;
 393         check(dom_window->GetDocument(getter_AddRefs(basic_doc)));
 394         nsCOMPtr<nsIDOMNSDocument> ns_doc(do_QueryInterface(basic_doc));
 395         assert(ns_doc);
 396         nsCOMPtr<nsIEventStateManager> event_state_man(
 397             pres_context->EventStateManager()); // does not AddRef
 398         assert(event_state_man);
 399         nsCOMPtr<nsIDOMDocumentEvent> event_factory(
 400             do_QueryInterface(basic_doc));
 401         assert(event_factory);
 402         nsCOMPtr<nsIDOMDocumentView> doc_view(do_QueryInterface(basic_doc));
 403         assert(doc_view);
 404         nsCOMPtr<nsIDOMAbstractView> view;
 405         check(doc_view->GetDefaultView(getter_AddRefs(view)));
 406
 407         // Set up or recover our iteration state.
 408         std::auto_ptr<page_state> state(page_state_);
 409         if (!state.get())
 410         {
 411             state.reset(
 412                 new page_state(
 413                     basic_doc, frame_params_.width, frame_params_.height));
 414
 415             state->spumux_file.open(state->spumux_temp.get_name().c_str());
 416             state->spumux_file <<
 417                 "<subpictures>\n"
 418                 "  <stream>\n"
 419                 "    <spu force='yes' start='00:00:00.00'\n"
 420                 "        highlight='" << state->links_temp.get_name() << "'\n"
 421                 "        select='" << state->links_temp.get_name() << "'>\n";
 422         }
 423
 424         rectangle window_rect = {
 425             0, 0, frame_params_.width, frame_params_.height
 426         };
 427
 428         for (/* no initialisation */;
 429              state->links_it != state->links_end;
 430              ++state->links_it)
 431         {
 432             nsCOMPtr<nsIDOMNode> node(*state->links_it);
 433
 434             // Find the link URI.
 435             nsCOMPtr<nsILink> link(do_QueryInterface(node));
 436             assert(link);
 437             nsCOMPtr<nsIURI> uri;
 438             check(link->GetHrefURI(getter_AddRefs(uri)));
 439             std::string uri_string;
 440             {
 441                 nsCString uri_ns_string;
 442                 check(uri->GetSpec(uri_ns_string));
 443                 uri_string.assign(uri_ns_string.BeginReading(),
 444                                   uri_ns_string.EndReading());
 445             }
 446             std::string uri_sans_fragment(uri_string, 0, uri_string.find('#'));
 447
 448             // Is this a new link?
 449             if (!state->link_changing)
 450             {
 451                 // Find a rectangle enclosing the link and clip it to the
 452                 // window.
 453                 nsCOMPtr<nsIDOMElement> elem(do_QueryInterface(node));
 454                 assert(elem);
 455                 state->link_rect = get_elem_rect(ns_doc, elem);
 456                 state->link_rect &= window_rect;
 457
 458                 if (state->link_rect.empty())
 459                 {
 460                     std::cerr << "Ignoring invisible link to "
 461                               << uri_string << "\n";
 462                     continue;
 463                 }
 464
 465                 ++state->link_num;
 466
 467                 if (state->link_num >= dvd::menu_buttons_max)
 468                 {
 469                     if (state->link_num == dvd::menu_buttons_max)
 470                         std::cerr << "No more than " << dvd::menu_buttons_max
 471                                   << " buttons can be placed on a page\n";
 472                     std::cerr << "Ignoring link to " << uri_string << "\n";
 473                     continue;
 474                 }
 475
 476                 // Check whether this is a link to a video or a page then
 477                 // add it to the known resources if not already seen.
 478                 nsCString path;
 479                 check(uri->GetPath(path));
 480                 // FIXME: This is a bit of a hack.  Perhaps we could decide
 481                 // later based on the MIME type determined by Mozilla?
 482                 if (path.Length() > 4
 483                     && std::strcmp(path.EndReading() - 4, ".vob") == 0)
 484                 {
 485                     PRBool is_file;
 486                     check(uri->SchemeIs("file", &is_file));
 487                     if (!is_file)
 488                     {
 489                         std::cerr << "Links to video must use the file:"
 490                                   << " scheme\n";
 491                         continue;
 492                     }
 493                     add_video(uri_sans_fragment);
 494                 }
 495                 else
 496                 {
 497                     add_page(uri_sans_fragment);
 498                 }
 499
 500                 nsCOMPtr<nsIContent> content(do_QueryInterface(node));
 501                 assert(content);
 502                 nsCOMPtr<nsIDOMEventTarget> event_target(
 503                     do_QueryInterface(node));
 504                 assert(event_target);
 505
 506                 state->norm_pixbuf = Gdk::Pixbuf::create(
 507                     Glib::RefPtr<Gdk::Drawable>(window),
 508                     window->get_colormap(),
 509                     state->link_rect.left,
 510                     state->link_rect.top,
 511                     0,
 512                     0,
 513                     state->link_rect.right - state->link_rect.left,
 514                     state->link_rect.bottom - state->link_rect.top);
 515
 516                 nsCOMPtr<nsIDOMEvent> event;
 517                 check(event_factory->CreateEvent(
 518                           NS_ConvertASCIItoUTF16("MouseEvents"),
 519                           getter_AddRefs(event)));
 520                 nsCOMPtr<nsIDOMMouseEvent> mouse_event(
 521                     do_QueryInterface(event));
 522                 assert(mouse_event);
 523                 check(mouse_event->InitMouseEvent(
 524                           NS_ConvertASCIItoUTF16("mouseover"),
 525                           true,  // can bubble
 526                           true,  // cancelable
 527                           view,
 528                           0,     // detail: mouse click count
 529                           state->link_rect.left, // screenX
 530                           state->link_rect.top,  // screenY
 531                           state->link_rect.left, // clientX
 532                           state->link_rect.top,  // clientY
 533                           false, false, false, false, // qualifiers
 534                           0,     // button: left (or primary)
 535                           0));   // related target
 536                 PRBool dummy;
 537                 check(event_target->DispatchEvent(mouse_event,
 538                                                   &dummy));
 539                 check(event_state_man->SetContentState(content,
 540                                                        NS_EVENT_STATE_HOVER));
 541
 542                 pres_shell->FlushPendingNotifications(true);
 543
 544                 // We may have to exit and wait for image loading
 545                 // to complete, at which point we will be called
 546                 // again.
 547                 if (pending_req_count_ > 0)
 548                 {
 549                     state->link_changing = true;
 550                     page_state_ = state;
 551                     return;
 552                 }
 553             }
 554
 555             window->process_updates(true);
 556
 557             Glib::RefPtr<Gdk::Pixbuf> changed_pixbuf(
 558                 Gdk::Pixbuf::create(
 559                     Glib::RefPtr<Gdk::Drawable>(window),
 560                     window->get_colormap(),
 561                     state->link_rect.left,
 562                     state->link_rect.top,
 563                     0,
 564                     0,
 565                     state->link_rect.right - state->link_rect.left,
 566                     state->link_rect.bottom - state->link_rect.top));
 567             diff_rgb_pixbufs(
 568                 state->norm_pixbuf,
 569                 changed_pixbuf,
 570                 state->diff_pixbuf,
 571                 state->link_rect.left,
 572                 state->link_rect.top,
 573                 state->link_rect.right - state->link_rect.left,
 574                 state->link_rect.bottom - state->link_rect.top);
 575
 576             state->spumux_file <<
 577                 "      <button x0='" << state->link_rect.left << "'"
 578                 " y0='" << state->link_rect.top << "'"
 579                 " x1='" << state->link_rect.right - 1 << "'"
 580                 " y1='" << state->link_rect.bottom - 1 << "'/>\n";
 581
 582             // Add to the page's links, ignoring any fragment (for now).
 583             page_links_.back().push_back(uri_sans_fragment);
 584         }
 585
 586         quantise_rgba_pixbuf(state->diff_pixbuf, dvd::button_n_colours);
 587
 588         std::cout << "saving " << state->links_temp.get_name()
 589                   << std::endl;
 590         state->diff_pixbuf->save(state->links_temp.get_name(), "png");
 591
 592         state->spumux_file <<
 593             "    </spu>\n"
 594             "  </stream>\n"
 595             "</subpictures>\n";
 596
 597         state->spumux_file.close();
 598
 599         // TODO: if (!state->spumux_file) throw ...
 600
 601         {
 602             boost::shared_ptr<temp_file> vob_temp(
 603                 new temp_file("webdvd-vob-"));
 604             std::ostringstream command_stream;
 605             command_stream << "pngtopnm "
 606                            << background_temp_->get_name()
 607                            << " | ppmtoy4m -v0 -n1 -F"
 608                            << frame_params_.rate_numer
 609                            << ":" << frame_params_.rate_denom
 610                            << " -A" << frame_params_.pixel_ratio_width
 611                            << ":" << frame_params_.pixel_ratio_height
 612                            << (" -Ip -S420_mpeg2"
 613                                " | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
 614                                " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
 615                                " | spumux -v0 -mdvd ")
 616                            << state->spumux_temp.get_name()
 617                            << " > " << vob_temp->get_name();
 618             std::string command(command_stream.str());
 619             const char * argv[] = {
 620                 "/bin/sh", "-c", command.c_str(), 0
 621             };
 622             std::cout << "running " << argv[2] << std::endl;
 623             int command_result;
 624             Glib::spawn_sync(".",
 625                              Glib::ArrayHandle<std::string>(
 626                                  argv, sizeof(argv)/sizeof(argv[0]),
 627                                  Glib::OWNERSHIP_NONE),
 628                              Glib::SPAWN_STDOUT_TO_DEV_NULL,
 629                              SigC::Slot0<void>(),
 630                              0, 0,
 631                              &command_result);
 632             if (command_result != 0)
 633                 throw std::runtime_error("spumux pipeline failed");
 634
 635             page_temp_files_.push_back(vob_temp);
 636         }
 637     }
 638
 639     void generate_page_dispatch(std::ostream &, int indent,
 640                                 int first_page, int last_page);
 641
 642     void WebDvdWindow::generate_dvd()
 643     {
 644         temp_file temp("webdvd-dvdauthor-");
 645         temp.close();
 646         std::ofstream file(temp.get_name().c_str());
 647
 648         // We generate code that uses registers in the following way:
 649         //
 650         // g0:     link destination (when jumping to menu 1), then scratch
 651         // g1:     current location
 652         // g2-g11: location history (g2 = most recent)
 653         // g12:    location that last linked to a video
 654         //
 655         // All locations are divided into two bitfields: the least
 656         // significant 10 bits are a page/menu number and the most
 657         // significant 6 bits are a link/button number.  This is
 658         // chosen for compatibility with the encoding of the s8
 659         // (button) register.
 660         //
 661         static const int link_mult = dvd::reg_s8_button_mult;
 662         static const int page_mask = link_mult - 1;
 663         static const int link_mask = (1 << dvd::reg_bits) - link_mult;
 664
 665         file <<
 666             "<dvdauthor>\n"
 667             "  <vmgm>\n"
 668             "    <menus>\n";
 669
 670         for (std::size_t page_num = 1;
 671              page_num <= page_links_.size();
 672              ++page_num)
 673         {
 674             std::vector<std::string> & page_links =
 675                 page_links_[page_num - 1];
 676
 677             if (page_num == 1)
 678             {
 679                 // This is the first page (root menu) which needs to
 680                 // include initialisation and dispatch code.
 681
 682                 file <<
 683                     "      <pgc entry='title'>\n"
 684                     "        <pre>\n"
 685                     // Has the location been set yet?
 686                     "          if (g1 eq 0)\n"
 687                     "          {\n"
 688                     // Initialise the current location to first link on
 689                     // this page.
 690                     "            g1 = " << 1 * link_mult + 1 << ";\n"
 691                     "          }\n"
 692                     "          else\n"
 693                     "          {\n"
 694                     // Has the user selected a link?
 695                     "            if (g0 ne 0)\n"
 696                     "            {\n"
 697                     // First update the history.
 698                     // Does link go to the last page in the history?
 699                     "              if (((g0 ^ g2) &amp; " << page_mask
 700                      << ") == 0)\n"
 701                     // It does; we treat this as going back and pop the old
 702                     // location off the history stack into the current
 703                     // location.  Clear the free stack slot.
 704                     "              {\n"
 705                     "                g1 = g2; g2 = g3; g3 = g4; g4 = g5;\n"
 706                     "                g5 = g6; g6 = g7; g7 = g8; g8 = g9;\n"
 707                     "                g9 = g10; g10 = g11; g11 = 0;\n"
 708                     "              }\n"
 709                     "              else\n"
 710                     // Link goes to some other page, so push current
 711                     // location onto the history stack and set the current
 712                     // location to be exactly the target location.
 713                     "              {\n"
 714                     "                g11 = g10; g10 = g9; g9 = g8; g8 = g7;\n"
 715                     "                g7 = g6; g6 = g5; g5 = g4; g4 = g3;\n"
 716                     "                g3 = g2; g2 = g1; g1 = g0;\n"
 717                     "              }\n"
 718                     "            }\n"
 719                     // Find the target page number.
 720                     "            g0 = g1 &amp; " << page_mask << ";\n";
 721                 // There seems to be no way to perform a computed jump,
 722                 // so we generate all possible jumps and a binary search
 723                 // to select the correct one.
 724                 generate_page_dispatch(file, 12, 1, page_links_.size());
 725                 file <<
 726                     "          }\n";
 727             }
 728             else // page_num != 1
 729             {
 730                 file <<
 731                     "      <pgc>\n"
 732                     "        <pre>\n";
 733             }
 734
 735             file <<
 736                 // Clear link indicator and highlight the
 737                 // appropriate link/button.
 738                 "          g0 = 0; s8 = g1 &amp; " << link_mask << ";\n"
 739                 "        </pre>\n"
 740                 "        <vob file='"
 741                  << page_temp_files_[page_num - 1]->get_name() << "'/>\n";
 742
 743             for (std::size_t link_num = 1;
 744                  link_num <= page_links.size();
 745                  ++link_num)
 746             {
 747                 file <<
 748                     "        <button>"
 749                     // Update current location.
 750                     " g1 = " << link_num * link_mult + page_num << ";";
 751
 752                 // Jump to appropriate resource.
 753                 const ResourceEntry & resource_loc =
 754                     resource_map_[page_links[link_num - 1]];
 755                 if (resource_loc.first == page_resource)
 756                     file <<
 757                         " g0 = " << 1 * link_mult + resource_loc.second << ";"
 758                         " jump menu 1;";
 759                 else if (resource_loc.first == video_resource)
 760                     file << " jump title " << resource_loc.second << ";";
 761
 762                 file <<  " </button>\n";
 763             }
 764
 765             file << "      </pgc>\n";
 766         }
 767
 768         file <<
 769             "    </menus>\n"
 770             "  </vmgm>\n";
 771
 772         // Generate a titleset for each video.  This appears to make
 773         // jumping to titles a whole lot simpler.
 774         for (std::size_t video_num = 1;
 775              video_num <= video_paths_.size();
 776              ++video_num)
 777         {
 778             file <<
 779                 "  <titleset>\n"
 780                 // Generate a dummy menu so that the menu button on the
 781                 // remote control will work.
 782                 "    <menus>\n"
 783                 "      <pgc entry='root'>\n"
 784                 "        <pre> jump vmgm menu; </pre>\n"
 785                 "      </pgc>\n"
 786                 "    </menus>\n"
 787                 "    <titles>\n"
 788                 "      <pgc>\n"
 789                 // Record calling page/menu.
 790                 "        <pre> g12 = g1; </pre>\n"
 791                 // FIXME: Should XML-escape the path
 792                 "        <vob file='" << video_paths_[video_num - 1]
 793                  << "'/>\n"
 794                 // If page/menu location has not been changed during the
 795                 // video, change the location to be the following
 796                 // link/button when returning to it.  In any case,
 797                 // return to a page/menu.
 798                 "        <post> if (g1 eq g12) g1 = g1 + " << link_mult
 799                  << "; call menu; </post>\n"
 800                 "      </pgc>\n"
 801                 "    </titles>\n"
 802                 "  </titleset>\n";
 803         }
 804
 805         file <<
 806             "</dvdauthor>\n";
 807
 808         file.close();
 809
 810         {
 811             const char * argv[] = {
 812                 "dvdauthor",
 813                 "-o", output_dir_.c_str(),
 814                 "-x", temp.get_name().c_str(),
 815                 0
 816             };
 817             int command_result;
 818             Glib::spawn_sync(".",
 819                              Glib::ArrayHandle<std::string>(
 820                                  argv, sizeof(argv)/sizeof(argv[0]),
 821                                  Glib::OWNERSHIP_NONE),
 822                              Glib::SPAWN_SEARCH_PATH
 823                              | Glib::SPAWN_STDOUT_TO_DEV_NULL,
 824                              SigC::Slot0<void>(),
 825                              0, 0,
 826                              &command_result);
 827             if (command_result != 0)
 828                 throw std::runtime_error("dvdauthor failed");
 829         }
 830     }
 831
 832     void generate_page_dispatch(std::ostream & file, int indent,
 833                                 int first_page, int last_page)
 834     {
 835         if (first_page == 1 && last_page == 1)
 836         {
 837             // The dispatch code is *on* page 1 so we must not dispatch to
 838             // page 1 since that would cause an infinite loop.  This case
 839             // should be unreachable if there is more than one page due
 840             // to the following case.
 841         }
 842         else if (first_page == 1 && last_page == 2)
 843         {
 844             // dvdauthor doesn't allow empty blocks or null statements so
 845             // when selecting between pages 1 and 2 we don't use an "else"
 846             // part.  We must use braces so that a following "else" will
 847             // match the right "if".
 848             file << std::setw(indent) << "" << "{\n"
 849                  << std::setw(indent) << "" << "if (g0 eq 2)\n"
 850                  << std::setw(indent + 2) << "" << "jump menu 2;\n"
 851                  << std::setw(indent) << "" << "}\n";
 852         }
 853         else if (first_page == last_page)
 854         {
 855             file << std::setw(indent) << ""
 856                  << "jump menu " << first_page << ";\n";
 857         }
 858         else
 859         {
 860             int middle = (first_page + last_page) / 2;
 861             file << std::setw(indent) << "" << "if (g0 le " << middle << ")\n";
 862             generate_page_dispatch(file, indent + 2, first_page, middle);
 863             file << std::setw(indent) << "" << "else\n";
 864             generate_page_dispatch(file, indent + 2, middle + 1, last_page);
 865         }
 866     }
 867
 868     const video::frame_params & lookup_frame_params(const char * str)
 869     {
 870         assert(str);
 871         static const struct { const char * str; bool is_ntsc; }
 872         known_strings[] = {
 873             { "NTSC",  true },
 874             { "ntsc",  true },
 875             { "PAL",   false },
 876             { "pal",   false },
 877             // For DVD purposes, SECAM can be treated identically to PAL.
 878             { "SECAM", false },
 879             { "secam", false }
 880         };
 881         for (std::size_t i = 0;
 882              i != sizeof(known_strings)/sizeof(known_strings[0]);
 883              ++i)
 884             if (std::strcmp(str, known_strings[i].str) == 0)
 885                 return known_strings[i].is_ntsc ?
 886                     video::ntsc_params : video::pal_params;
 887         throw std::runtime_error(
 888             std::string("Invalid video standard: ").append(str));
 889     }
 890
 891     void print_usage(std::ostream & stream, const char * command_name)
 892     {
 893         stream << "Usage: " << command_name
 894                << (" [gtk-options] [--video-std std-name]"
 895                    " [--preview] menu-url [output-dir]\n");
 896     }
 897
 898 } // namespace
 899
 900 int main(int argc, char ** argv)
 901 {
 902     try
 903     {
 904         video::frame_params frame_params = video::pal_params;
 905         bool preview_mode = false;
 906
 907         // Do initial argument parsing.  We have to do this before
 908         // letting Gtk parse the arguments since we may need to spawn
 909         // Xvfb first.
 910         int argi = 1;
 911         while (argi != argc)
 912         {
 913             if (std::strcmp(argv[argi], "--") == 0)
 914             {
 915                 break;
 916             }
 917             else if (std::strcmp(argv[argi], "--help") == 0)
 918             {
 919                 print_usage(std::cout, argv[0]);
 920                 return EXIT_SUCCESS;
 921             }
 922             else if (std::strcmp(argv[argi], "--preview") == 0)
 923             {
 924                 preview_mode = true;
 925                 argi += 1;
 926             }
 927             else if (std::strcmp(argv[argi], "--video-std") == 0)
 928             {
 929                 if (argi + 1 == argc)
 930                 {
 931                     std::cerr << "Missing argument to --video-std\n";
 932                     print_usage(std::cerr, argv[0]);
 933                     return EXIT_FAILURE;
 934                 }
 935                 frame_params = lookup_frame_params(argv[argi + 1]);
 936                 argi += 2;
 937             }
 938             else
 939             {
 940                 argi += 1;
 941             }
 942         }
 943
 944         std::auto_ptr<FrameBuffer> fb;
 945         if (!preview_mode)
 946         {
 947             // Spawn Xvfb and set env variables so that Xlib will use it
 948             // Use 8 bits each for RGB components, which should translate into
 949             // "enough" bits for YUV components.
 950             fb.reset(new FrameBuffer(frame_params.width, frame_params.height,
 951                                      3 * 8));
 952             setenv("XAUTHORITY", fb->get_x_authority().c_str(), true);
 953             setenv("DISPLAY", fb->get_x_display().c_str(), true);
 954         }
 955
 956         // Initialise Gtk
 957         Gtk::Main kit(argc, argv);
 958
 959         // Complete argument parsing with Gtk's options out of the way.
 960         argi = 1;
 961         while (argi != argc)
 962         {
 963             if (std::strcmp(argv[argi], "--") == 0)
 964             {
 965                 argi += 1;
 966                 break;
 967             }
 968             else if (std::strcmp(argv[argi], "--preview") == 0)
 969             {
 970                 argi += 1;
 971             }
 972             else if (std::strcmp(argv[argi], "--video-std") == 0)
 973             {
 974                 argi += 2;
 975             }
 976             else if (argv[argi][0] == '-')
 977             {
 978                 std::cerr << "Invalid option: " << argv[argi] << "\n";
 979                 print_usage(std::cerr, argv[0]);
 980                 return EXIT_FAILURE;
 981             }
 982             else
 983             {
 984                 break;
 985             }
 986         }
 987         if (argc - argi != (preview_mode ? 1 : 2))
 988         {
 989             print_usage(std::cerr, argv[0]);
 990             return EXIT_FAILURE;
 991         }
 992
 993         // Initialise Mozilla
 994         BrowserWidget::init();
 995
 996         WebDvdWindow window(frame_params,
 997                             argv[argi],
 998                             preview_mode ? "" : argv[argi + 1]);
 999         Gtk::Main::run(window);
1000     }
1001     catch (std::exception & e)
1002     {
1003         std::cerr << "Fatal error: " << e.what() << "\n";
1004         return EXIT_FAILURE;
1005     }
1006
1007     return EXIT_SUCCESS;
1008 }