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