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 <cstring>
   6 #include <exception>
   7 #include <fstream>
   8 #include <iomanip>
   9 #include <iostream>
  10 #include <memory>
  11 #include <queue>
  12 #include <set>
  13 #include <sstream>
  14 #include <string>
  15
  16 #include <stdlib.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 <nsIDOMBarProp.h>
  33 #include <nsIDOMDocumentEvent.h>
  34 #include <nsIDOMDocumentView.h>
  35 #include <nsIDOMElement.h>
  36 #include <nsIDOMEventTarget.h>
  37 #include <nsIDOMHTMLDocument.h>
  38 #include <nsIDOMMouseEvent.h>
  39 #include <nsIDOMNSDocument.h>
  40 #include <nsIDOMWindow.h>
  41 #include <nsIEventStateManager.h>
  42 #include <nsIInterfaceRequestorUtils.h>
  43 #include <nsIURI.h> // required before nsILink.h
  44 #include <nsILink.h>
  45 #include <nsIPresContext.h>
  46 #include <nsIPresShell.h>
  47 #include <nsIWebBrowser.h>
  48 #include <nsString.h>
  49
  50 #include "browserwidget.hpp"
  51 #include "childiterator.hpp"
  52 #include "dvd.hpp"
  53 #include "framebuffer.hpp"
  54 #include "linkiterator.hpp"
  55 #include "pixbufs.hpp"
  56 #include "stylesheets.hpp"
  57 #include "temp_file.hpp"
  58 #include "video.hpp"
  59 #include "xpcom_support.hpp"
  60
  61 using xpcom_support::check;
  62
  63 namespace
  64 {
  65     struct rectangle
  66     {
  67         int left, top;     // inclusive
  68         int right, bottom; // exclusive
  69
  70         rectangle operator|=(const rectangle & other)
  71             {
  72                 if (other.empty())
  73                 {
  74                     // use current extents unchanged
  75                 }
  76                 else if (empty())
  77                 {
  78                     // use other extents
  79                     *this = other;
  80                 }
  81                 else
  82                 {
  83                     // find rectangle enclosing both extents
  84                     left = std::min(left, other.left);
  85                     top = std::min(top, other.top);
  86                     right = std::max(right, other.right);
  87                     bottom = std::max(bottom, other.bottom);
  88                 }
  89
  90                 return *this;
  91             }
  92
  93         rectangle operator&=(const rectangle & other)
  94             {
  95                 // find rectangle enclosed in both extents
  96                 left = std::max(left, other.left);
  97                 top = std::max(top, other.top);
  98                 right = std::max(left, std::min(right, other.right));
  99                 bottom = std::max(top, std::min(bottom, other.bottom));
 100                 return *this;
 101             }
 102
 103         bool empty() const
 104             {
 105                 return left == right || bottom == top;
 106             }
 107     };
 108
 109     rectangle get_elem_rect(nsIDOMNSDocument * ns_doc,
 110                             nsIDOMElement * elem)
 111     {
 112         rectangle result;
 113
 114         // Start with this element's bounding box
 115         nsCOMPtr<nsIBoxObject> box;
 116         check(ns_doc->GetBoxObjectFor(elem, getter_AddRefs(box)));
 117         int width, height;
 118         check(box->GetScreenX(&result.left));
 119         check(box->GetScreenY(&result.top));
 120         check(box->GetWidth(&width));
 121         check(box->GetHeight(&height));
 122         result.right = result.left + width;
 123         result.bottom = result.top + height;
 124
 125         // Merge bounding boxes of all child elements
 126         for (ChildIterator it = ChildIterator(elem), end; it != end; ++it)
 127         {
 128             nsCOMPtr<nsIDOMNode> child_node(*it);
 129             PRUint16 child_type;
 130             if (check(child_node->GetNodeType(&child_type)),
 131                 child_type == nsIDOMNode::ELEMENT_NODE)
 132             {
 133                 nsCOMPtr<nsIDOMElement> child_elem(
 134                     do_QueryInterface(child_node));
 135                 result |= get_elem_rect(ns_doc, child_elem);
 136             }
 137         }
 138
 139         return result;
 140     }
 141
 142     class WebDvdWindow : public Gtk::Window
 143     {
 144     public:
 145         WebDvdWindow(
 146             const video::frame_params & frame_params,
 147             const std::string & main_page_uri,
 148             const std::string & output_dir);
 149
 150     private:
 151         void add_page(const std::string & uri);
 152         void add_video(const std::string & uri);
 153         void load_next_page();
 154         void on_net_state_change(const char * uri, gint flags, guint status);
 155         bool process_page();
 156         void save_screenshot();
 157         void process_links(nsIPresShell * pres_shell,
 158                            nsIPresContext * pres_context,
 159                            nsIDOMWindow * dom_window);
 160         void generate_dvd();
 161
 162         enum ResourceType { page_resource, video_resource };
 163         typedef std::pair<ResourceType, int> ResourceEntry;
 164         video::frame_params frame_params_;
 165         std::string output_dir_;
 166         BrowserWidget browser_widget_;
 167         nsCOMPtr<nsIStyleSheet> stylesheet_;
 168         std::queue<std::string> page_queue_;
 169         std::map<std::string, ResourceEntry> resource_map_;
 170         std::vector<std::vector<std::string> > page_links_;
 171         std::vector<std::string> video_paths_;
 172         bool pending_window_update_;
 173         int pending_req_count_;
 174         bool have_tweaked_page_;
 175         std::auto_ptr<temp_file> background_temp_;
 176         struct page_state;
 177         std::auto_ptr<page_state> page_state_;
 178         std::vector<boost::shared_ptr<temp_file> > page_temp_files_;
 179     };
 180
 181     WebDvdWindow::WebDvdWindow(
 182         const video::frame_params & frame_params,
 183         const std::string & main_page_uri,
 184         const std::string & output_dir)
 185             : frame_params_(frame_params),
 186               output_dir_(output_dir),
 187               stylesheet_(load_css("file://" WEBDVD_LIB_DIR "/webdvd.css")),
 188               pending_window_update_(false),
 189               pending_req_count_(0),
 190               have_tweaked_page_(false)
 191     {
 192         set_size_request(frame_params_.width, frame_params_.height);
 193         set_resizable(false);
 194
 195         add(browser_widget_);
 196         browser_widget_.show();
 197         browser_widget_.signal_net_state().connect(
 198             SigC::slot(*this, &WebDvdWindow::on_net_state_change));
 199
 200         add_page(main_page_uri);
 201         load_next_page();
 202     }
 203
 204     void WebDvdWindow::add_page(const std::string & uri)
 205     {
 206         if (resource_map_.insert(
 207                 std::make_pair(uri, ResourceEntry(page_resource, 0)))
 208             .second)
 209         {
 210             page_queue_.push(uri);
 211         }
 212     }
 213
 214     void WebDvdWindow::add_video(const std::string & uri)
 215     {
 216         if (resource_map_.insert(
 217                 std::make_pair(uri, ResourceEntry(video_resource,
 218                                                   video_paths_.size() + 1)))
 219             .second)
 220         {
 221             Glib::ustring hostname;
 222             std::string filename(Glib::filename_from_uri(uri, hostname));
 223             // FIXME: Should check the hostname
 224             if (!Glib::file_test(filename, Glib::FILE_TEST_IS_REGULAR))
 225                 throw std::runtime_error(
 226                     filename + " is missing or not a regular file");
 227             video_paths_.push_back(filename);
 228         }
 229     }
 230
 231     void WebDvdWindow::load_next_page()
 232     {
 233         assert(!page_queue_.empty());
 234         const std::string & uri = page_queue_.front();
 235         std::cout << "loading " << uri << std::endl;
 236
 237         std::size_t page_count = page_links_.size();
 238         resource_map_[uri].second = ++page_count;
 239         page_links_.resize(page_count);
 240
 241         browser_widget_.load_uri(uri);
 242     }
 243
 244     void WebDvdWindow::on_net_state_change(const char * uri,
 245                                            gint flags, guint status)
 246     {
 247         if (flags & GTK_MOZ_EMBED_FLAG_IS_REQUEST)
 248         {
 249             if (flags & GTK_MOZ_EMBED_FLAG_START)
 250                 ++pending_req_count_;
 251
 252             if (flags & GTK_MOZ_EMBED_FLAG_STOP)
 253             {
 254                 assert(pending_req_count_ != 0);
 255                 --pending_req_count_;
 256             }
 257         }
 258
 259         if (flags & GTK_MOZ_EMBED_FLAG_IS_DOCUMENT
 260             && flags & GTK_MOZ_EMBED_FLAG_START)
 261         {
 262             pending_window_update_ = true;
 263             have_tweaked_page_ = false;
 264         }
 265
 266         if (flags & GTK_MOZ_EMBED_FLAG_IS_WINDOW
 267             && flags & GTK_MOZ_EMBED_FLAG_STOP)
 268         {
 269             // Check whether the load was successful, ignoring this
 270             // pseudo-error.
 271             if (status != NS_IMAGELIB_ERROR_LOAD_ABORTED)
 272                 check(status);
 273
 274             pending_window_update_ = false;
 275         }
 276
 277         if (pending_req_count_ == 0 && !pending_window_update_)
 278         {
 279             try
 280             {
 281                 if (!process_page())
 282                     Gtk::Main::quit();
 283             }
 284             catch (std::exception & e)
 285             {
 286                 std::cerr << "Fatal error";
 287                 if (!page_queue_.empty())
 288                     std::cerr << " while processing <" << page_queue_.front()
 289                               << ">";
 290                 std::cerr << ": " << e.what() << "\n";
 291                 Gtk::Main::quit();
 292             }
 293         }
 294     }
 295
 296     bool WebDvdWindow::process_page()
 297     {
 298         assert(!page_queue_.empty());
 299
 300         nsCOMPtr<nsIWebBrowser> browser(browser_widget_.get_browser());
 301         nsCOMPtr<nsIDocShell> doc_shell(do_GetInterface(browser));
 302         assert(doc_shell);
 303         nsCOMPtr<nsIPresShell> pres_shell;
 304         check(doc_shell->GetPresShell(getter_AddRefs(pres_shell)));
 305         nsCOMPtr<nsIPresContext> pres_context;
 306         check(doc_shell->GetPresContext(getter_AddRefs(pres_context)));
 307         nsCOMPtr<nsIDOMWindow> dom_window;
 308         check(browser->GetContentDOMWindow(getter_AddRefs(dom_window)));
 309
 310         // If we haven't done so already, apply the stylesheet and
 311         // disable scrollbars.
 312         if (!have_tweaked_page_)
 313         {
 314             apply_style_sheet(stylesheet_, pres_shell);
 315
 316             // This actually only needs to be done once.
 317             nsCOMPtr<nsIDOMBarProp> dom_bar_prop;
 318             check(dom_window->GetScrollbars(getter_AddRefs(dom_bar_prop)));
 319             check(dom_bar_prop->SetVisible(false));
 320
 321             have_tweaked_page_ = true;
 322
 323             // Might need to wait a while for things to load or more
 324             // likely for a re-layout.
 325             if (pending_req_count_ > 0)
 326                 return true;
 327         }
 328
 329         // All further work should only be done if we're not in preview mode.
 330         if (!output_dir_.empty())
 331         {
 332             // If we haven't already started work on this page, save a
 333             // screenshot of its normal appearance.
 334             if (!page_state_.get())
 335                 save_screenshot();
 336
 337             // Start or continue processing links.
 338             process_links(pres_shell, pres_context, dom_window);
 339
 340             // If we've finished work on the links, move on to the
 341             // next page, if any, or else generate the DVD filesystem.
 342             if (!page_state_.get())
 343             {
 344                 page_queue_.pop();
 345                 if (page_queue_.empty())
 346                 {
 347                     generate_dvd();
 348                     return false;
 349                 }
 350                 else
 351                 {
 352                     load_next_page();
 353                 }
 354             }
 355         }
 356
 357         return true;
 358     }
 359
 360     void WebDvdWindow::save_screenshot()
 361     {
 362         Glib::RefPtr<Gdk::Window> window(get_window());
 363         assert(window);
 364         window->process_updates(true);
 365
 366         background_temp_.reset(new temp_file("webdvd-back-"));
 367         background_temp_->close();
 368         std::cout << "saving " << background_temp_->get_name() << std::endl;
 369         Gdk::Pixbuf::create(Glib::RefPtr<Gdk::Drawable>(window),
 370                             window->get_colormap(),
 371                             0, 0, 0, 0,
 372                             frame_params_.width, frame_params_.height)
 373             ->save(background_temp_->get_name(), "png");
 374     }
 375
 376     struct WebDvdWindow::page_state
 377     {
 378         page_state(nsIDOMDocument * doc, int width, int height)
 379                 : diff_pixbuf(Gdk::Pixbuf::create(
 380                                   Gdk::COLORSPACE_RGB,
 381                                   true, 8, // has_alpha, bits_per_sample
 382                                   width, height)),
 383                   spumux_temp("webdvd-spumux-"),
 384                   links_temp("webdvd-links-"),
 385                   link_num(0),
 386                   links_it(doc),
 387                   link_changing(false)
 388             {
 389                 spumux_temp.close();
 390                 links_temp.close();
 391             }
 392
 393         Glib::RefPtr<Gdk::Pixbuf> diff_pixbuf;
 394
 395         temp_file spumux_temp;
 396         std::ofstream spumux_file;
 397
 398         temp_file links_temp;
 399
 400         int link_num;
 401         LinkIterator links_it, links_end;
 402
 403         rectangle link_rect;
 404         bool link_changing;
 405         Glib::RefPtr<Gdk::Pixbuf> norm_pixbuf;
 406     };
 407
 408     void WebDvdWindow::process_links(nsIPresShell * pres_shell,
 409                                      nsIPresContext * pres_context,
 410                                      nsIDOMWindow * dom_window)
 411     {
 412         Glib::RefPtr<Gdk::Window> window(get_window());
 413         assert(window);
 414
 415         nsCOMPtr<nsIDOMDocument> basic_doc;
 416         check(dom_window->GetDocument(getter_AddRefs(basic_doc)));
 417         nsCOMPtr<nsIDOMNSDocument> ns_doc(do_QueryInterface(basic_doc));
 418         assert(ns_doc);
 419         nsCOMPtr<nsIEventStateManager> event_state_man(
 420             pres_context->EventStateManager()); // does not AddRef
 421         assert(event_state_man);
 422         nsCOMPtr<nsIDOMDocumentEvent> event_factory(
 423             do_QueryInterface(basic_doc));
 424         assert(event_factory);
 425         nsCOMPtr<nsIDOMDocumentView> doc_view(do_QueryInterface(basic_doc));
 426         assert(doc_view);
 427         nsCOMPtr<nsIDOMAbstractView> view;
 428         check(doc_view->GetDefaultView(getter_AddRefs(view)));
 429
 430         // Set up or recover our iteration state.
 431         std::auto_ptr<page_state> state(page_state_);
 432         if (!state.get())
 433         {
 434             state.reset(
 435                 new page_state(
 436                     basic_doc, frame_params_.width, frame_params_.height));
 437
 438             state->spumux_file.open(state->spumux_temp.get_name().c_str());
 439             state->spumux_file <<
 440                 "<subpictures>\n"
 441                 "  <stream>\n"
 442                 "    <spu force='yes' start='00:00:00.00'\n"
 443                 "        highlight='" << state->links_temp.get_name() << "'\n"
 444                 "        select='" << state->links_temp.get_name() << "'>\n";
 445         }
 446
 447         rectangle window_rect = {
 448             0, 0, frame_params_.width, frame_params_.height
 449         };
 450
 451         for (/* no initialisation */;
 452              state->links_it != state->links_end;
 453              ++state->links_it)
 454         {
 455             nsCOMPtr<nsIDOMNode> node(*state->links_it);
 456
 457             // Find the link URI.
 458             nsCOMPtr<nsILink> link(do_QueryInterface(node));
 459             assert(link);
 460             nsCOMPtr<nsIURI> uri;
 461             check(link->GetHrefURI(getter_AddRefs(uri)));
 462             std::string uri_string;
 463             {
 464                 nsCString uri_ns_string;
 465                 check(uri->GetSpec(uri_ns_string));
 466                 uri_string.assign(uri_ns_string.BeginReading(),
 467                                   uri_ns_string.EndReading());
 468             }
 469             std::string uri_sans_fragment(uri_string, 0, uri_string.find('#'));
 470
 471             // Is this a new link?
 472             if (!state->link_changing)
 473             {
 474                 // Find a rectangle enclosing the link and clip it to the
 475                 // window.
 476                 nsCOMPtr<nsIDOMElement> elem(do_QueryInterface(node));
 477                 assert(elem);
 478                 state->link_rect = get_elem_rect(ns_doc, elem);
 479                 state->link_rect &= window_rect;
 480
 481                 if (state->link_rect.empty())
 482                 {
 483                     std::cerr << "Ignoring invisible link to "
 484                               << uri_string << "\n";
 485                     continue;
 486                 }
 487
 488                 ++state->link_num;
 489
 490                 if (state->link_num >= dvd::menu_buttons_max)
 491                 {
 492                     if (state->link_num == dvd::menu_buttons_max)
 493                         std::cerr << "No more than " << dvd::menu_buttons_max
 494                                   << " buttons can be placed on a page\n";
 495                     std::cerr << "Ignoring link to " << uri_string << "\n";
 496                     continue;
 497                 }
 498
 499                 // Check whether this is a link to a video or a page then
 500                 // add it to the known resources if not already seen.
 501                 nsCString path;
 502                 check(uri->GetPath(path));
 503                 // FIXME: This is a bit of a hack.  Perhaps we could decide
 504                 // later based on the MIME type determined by Mozilla?
 505                 if ((path.Length() > 4
 506                      && std::strcmp(path.EndReading() - 4, ".vob") == 0)
 507                     || (path.Length() > 8
 508                         && std::strcmp(path.EndReading() - 8, ".voblist")
 509                            == 0))
 510                 {
 511                     PRBool is_file;
 512                     check(uri->SchemeIs("file", &is_file));
 513                     if (!is_file)
 514                     {
 515                         std::cerr << "Links to video must use the file:"
 516                                   << " scheme\n";
 517                         continue;
 518                     }
 519                     add_video(uri_sans_fragment);
 520                 }
 521                 else
 522                 {
 523                     add_page(uri_sans_fragment);
 524                 }
 525
 526                 nsCOMPtr<nsIContent> content(do_QueryInterface(node));
 527                 assert(content);
 528                 nsCOMPtr<nsIDOMEventTarget> event_target(
 529                     do_QueryInterface(node));
 530                 assert(event_target);
 531
 532                 state->norm_pixbuf = Gdk::Pixbuf::create(
 533                     Glib::RefPtr<Gdk::Drawable>(window),
 534                     window->get_colormap(),
 535                     state->link_rect.left,
 536                     state->link_rect.top,
 537                     0,
 538                     0,
 539                     state->link_rect.right - state->link_rect.left,
 540                     state->link_rect.bottom - state->link_rect.top);
 541
 542                 nsCOMPtr<nsIDOMEvent> event;
 543                 check(event_factory->CreateEvent(
 544                           NS_ConvertASCIItoUTF16("MouseEvents"),
 545                           getter_AddRefs(event)));
 546                 nsCOMPtr<nsIDOMMouseEvent> mouse_event(
 547                     do_QueryInterface(event));
 548                 assert(mouse_event);
 549                 check(mouse_event->InitMouseEvent(
 550                           NS_ConvertASCIItoUTF16("mouseover"),
 551                           true,  // can bubble
 552                           true,  // cancelable
 553                           view,
 554                           0,     // detail: mouse click count
 555                           state->link_rect.left, // screenX
 556                           state->link_rect.top,  // screenY
 557                           state->link_rect.left, // clientX
 558                           state->link_rect.top,  // clientY
 559                           false, false, false, false, // qualifiers
 560                           0,     // button: left (or primary)
 561                           0));   // related target
 562                 PRBool dummy;
 563                 check(event_target->DispatchEvent(mouse_event,
 564                                                   &dummy));
 565                 check(event_state_man->SetContentState(content,
 566                                                        NS_EVENT_STATE_HOVER));
 567
 568                 pres_shell->FlushPendingNotifications(true);
 569
 570                 // We may have to exit and wait for image loading
 571                 // to complete, at which point we will be called
 572                 // again.
 573                 if (pending_req_count_ > 0)
 574                 {
 575                     state->link_changing = true;
 576                     page_state_ = state;
 577                     return;
 578                 }
 579             }
 580
 581             window->process_updates(true);
 582
 583             Glib::RefPtr<Gdk::Pixbuf> changed_pixbuf(
 584                 Gdk::Pixbuf::create(
 585                     Glib::RefPtr<Gdk::Drawable>(window),
 586                     window->get_colormap(),
 587                     state->link_rect.left,
 588                     state->link_rect.top,
 589                     0,
 590                     0,
 591                     state->link_rect.right - state->link_rect.left,
 592                     state->link_rect.bottom - state->link_rect.top));
 593             diff_rgb_pixbufs(
 594                 state->norm_pixbuf,
 595                 changed_pixbuf,
 596                 state->diff_pixbuf,
 597                 state->link_rect.left,
 598                 state->link_rect.top,
 599                 state->link_rect.right - state->link_rect.left,
 600                 state->link_rect.bottom - state->link_rect.top);
 601
 602             state->spumux_file <<
 603                 "      <button x0='" << state->link_rect.left << "'"
 604                 " y0='" << state->link_rect.top << "'"
 605                 " x1='" << state->link_rect.right - 1 << "'"
 606                 " y1='" << state->link_rect.bottom - 1 << "'/>\n";
 607
 608             // Add to the page's links, ignoring any fragment (for now).
 609             page_links_.back().push_back(uri_sans_fragment);
 610         }
 611
 612         quantise_rgba_pixbuf(state->diff_pixbuf, dvd::button_n_colours);
 613
 614         std::cout << "saving " << state->links_temp.get_name()
 615                   << std::endl;
 616         state->diff_pixbuf->save(state->links_temp.get_name(), "png");
 617
 618         state->spumux_file <<
 619             "    </spu>\n"
 620             "  </stream>\n"
 621             "</subpictures>\n";
 622
 623         state->spumux_file.close();
 624
 625         // TODO: if (!state->spumux_file) throw ...
 626
 627         {
 628             boost::shared_ptr<temp_file> vob_temp(
 629                 new temp_file("webdvd-vob-"));
 630             std::ostringstream command_stream;
 631             command_stream << "pngtopnm "
 632                            << background_temp_->get_name()
 633                            << " | ppmtoy4m -v0 -n1 -F"
 634                            << frame_params_.rate_numer
 635                            << ":" << frame_params_.rate_denom
 636                            << " -A" << frame_params_.pixel_ratio_width
 637                            << ":" << frame_params_.pixel_ratio_height
 638                            << (" -Ip -S420_mpeg2"
 639                                " | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
 640                                " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
 641                                " | spumux -v0 -mdvd ")
 642                            << state->spumux_temp.get_name()
 643                            << " > " << vob_temp->get_name();
 644             std::string command(command_stream.str());
 645             const char * argv[] = {
 646                 "/bin/sh", "-c", command.c_str(), 0
 647             };
 648             std::cout << "running " << argv[2] << std::endl;
 649             int command_result;
 650             Glib::spawn_sync(".",
 651                              Glib::ArrayHandle<std::string>(
 652                                  argv, sizeof(argv)/sizeof(argv[0]),
 653                                  Glib::OWNERSHIP_NONE),
 654                              Glib::SPAWN_STDOUT_TO_DEV_NULL,
 655                              SigC::Slot0<void>(),
 656                              0, 0,
 657                              &command_result);
 658             if (command_result != 0)
 659                 throw std::runtime_error("spumux pipeline failed");
 660
 661             page_temp_files_.push_back(vob_temp);
 662         }
 663     }
 664
 665     void generate_page_dispatch(std::ostream &, int indent,
 666                                 int first_page, int last_page);
 667
 668     void WebDvdWindow::generate_dvd()
 669     {
 670         temp_file temp("webdvd-dvdauthor-");
 671         temp.close();
 672         std::ofstream file(temp.get_name().c_str());
 673
 674         // We generate code that uses registers in the following way:
 675         //
 676         // g0:     link destination (when jumping to menu 1), then scratch
 677         // g1:     current location
 678         // g2-g11: location history (g2 = most recent)
 679         // g12:    location that last linked to a video
 680         //
 681         // All locations are divided into two bitfields: the least
 682         // significant 10 bits are a page/menu number and the most
 683         // significant 6 bits are a link/button number.  This is
 684         // chosen for compatibility with the encoding of the s8
 685         // (button) register.
 686         //
 687         static const int link_mult = dvd::reg_s8_button_mult;
 688         static const int page_mask = link_mult - 1;
 689         static const int link_mask = (1 << dvd::reg_bits) - link_mult;
 690
 691         file <<
 692             "<dvdauthor>\n"
 693             "  <vmgm>\n"
 694             "    <menus>\n";
 695
 696         for (std::size_t page_num = 1;
 697              page_num <= page_links_.size();
 698              ++page_num)
 699         {
 700             std::vector<std::string> & page_links =
 701                 page_links_[page_num - 1];
 702
 703             if (page_num == 1)
 704             {
 705                 // This is the first page (root menu) which needs to
 706                 // include initialisation and dispatch code.
 707
 708                 file <<
 709                     "      <pgc entry='title'>\n"
 710                     "        <pre>\n"
 711                     // Has the location been set yet?
 712                     "          if (g1 eq 0)\n"
 713                     "          {\n"
 714                     // Initialise the current location to first link on
 715                     // this page.
 716                     "            g1 = " << 1 * link_mult + 1 << ";\n"
 717                     "          }\n"
 718                     "          else\n"
 719                     "          {\n"
 720                     // Has the user selected a link?
 721                     "            if (g0 ne 0)\n"
 722                     "            {\n"
 723                     // First update the history.
 724                     // Does link go to the last page in the history?
 725                     "              if (((g0 ^ g2) &amp; " << page_mask
 726                      << ") == 0)\n"
 727                     // It does; we treat this as going back and pop the old
 728                     // location off the history stack into the current
 729                     // location.  Clear the free stack slot.
 730                     "              {\n"
 731                     "                g1 = g2; g2 = g3; g3 = g4; g4 = g5;\n"
 732                     "                g5 = g6; g6 = g7; g7 = g8; g8 = g9;\n"
 733                     "                g9 = g10; g10 = g11; g11 = 0;\n"
 734                     "              }\n"
 735                     "              else\n"
 736                     // Link goes to some other page, so push current
 737                     // location onto the history stack and set the current
 738                     // location to be exactly the target location.
 739                     "              {\n"
 740                     "                g11 = g10; g10 = g9; g9 = g8; g8 = g7;\n"
 741                     "                g7 = g6; g6 = g5; g5 = g4; g4 = g3;\n"
 742                     "                g3 = g2; g2 = g1; g1 = g0;\n"
 743                     "              }\n"
 744                     "            }\n"
 745                     // Find the target page number.
 746                     "            g0 = g1 &amp; " << page_mask << ";\n";
 747                 // There seems to be no way to perform a computed jump,
 748                 // so we generate all possible jumps and a binary search
 749                 // to select the correct one.
 750                 generate_page_dispatch(file, 12, 1, page_links_.size());
 751                 file <<
 752                     "          }\n";
 753             }
 754             else // page_num != 1
 755             {
 756                 file <<
 757                     "      <pgc>\n"
 758                     "        <pre>\n";
 759             }
 760
 761             file <<
 762                 // Clear link indicator and highlight the
 763                 // appropriate link/button.
 764                 "          g0 = 0; s8 = g1 &amp; " << link_mask << ";\n"
 765                 "        </pre>\n"
 766                 "        <vob file='"
 767                  << page_temp_files_[page_num - 1]->get_name() << "'/>\n";
 768
 769             for (std::size_t link_num = 1;
 770                  link_num <= page_links.size();
 771                  ++link_num)
 772             {
 773                 file <<
 774                     "        <button>"
 775                     // Update current location.
 776                     " g1 = " << link_num * link_mult + page_num << ";";
 777
 778                 // Jump to appropriate resource.
 779                 const ResourceEntry & resource_loc =
 780                     resource_map_[page_links[link_num - 1]];
 781                 if (resource_loc.first == page_resource)
 782                     file <<
 783                         " g0 = " << 1 * link_mult + resource_loc.second << ";"
 784                         " jump menu 1;";
 785                 else if (resource_loc.first == video_resource)
 786                     file << " jump title " << resource_loc.second << ";";
 787
 788                 file <<  " </button>\n";
 789             }
 790
 791             file << "      </pgc>\n";
 792         }
 793
 794         file <<
 795             "    </menus>\n"
 796             "  </vmgm>\n";
 797
 798         // Generate a titleset for each video.  This appears to make
 799         // jumping to titles a whole lot simpler.
 800         for (std::size_t video_num = 1;
 801              video_num <= video_paths_.size();
 802              ++video_num)
 803         {
 804             file <<
 805                 "  <titleset>\n"
 806                 // Generate a dummy menu so that the menu button on the
 807                 // remote control will work.
 808                 "    <menus>\n"
 809                 "      <pgc entry='root'>\n"
 810                 "        <pre> jump vmgm menu; </pre>\n"
 811                 "      </pgc>\n"
 812                 "    </menus>\n"
 813                 "    <titles>\n"
 814                 "      <pgc>\n"
 815                 // Record calling page/menu.
 816                 "        <pre> g12 = g1; </pre>\n";
 817
 818             // Write a reference to a linked VOB file, or the contents
 819             // of a linked VOB list file.
 820             const std::string & video_path = video_paths_[video_num - 1];
 821             if (video_path.compare(video_path.size() - 4, 4, ".vob") == 0)
 822             {
 823                 // FIXME: Should XML-escape the path
 824                 file << "        <vob file='" << video_path << "'/>\n";
 825             }
 826             else
 827             {
 828                 assert(video_path.compare(video_path.size() - 8, 8,
 829                                           ".voblist") == 0);
 830                 // TODO: Validate the file contents;
 831                 file << Glib::file_get_contents(video_path);
 832             }
 833
 834             file <<
 835                 // If page/menu location has not been changed during the
 836                 // video, change the location to be the following
 837                 // link/button when returning to it.  In any case,
 838                 // return to a page/menu.
 839                 "        <post> if (g1 eq g12) g1 = g1 + " << link_mult
 840                  << "; call menu; </post>\n"
 841                 "      </pgc>\n"
 842                 "    </titles>\n"
 843                 "  </titleset>\n";
 844         }
 845
 846         file <<
 847             "</dvdauthor>\n";
 848
 849         file.close();
 850
 851         {
 852             const char * argv[] = {
 853                 "dvdauthor",
 854                 "-o", output_dir_.c_str(),
 855                 "-x", temp.get_name().c_str(),
 856                 0
 857             };
 858             int command_result;
 859             Glib::spawn_sync(".",
 860                              Glib::ArrayHandle<std::string>(
 861                                  argv, sizeof(argv)/sizeof(argv[0]),
 862                                  Glib::OWNERSHIP_NONE),
 863                              Glib::SPAWN_SEARCH_PATH
 864                              | Glib::SPAWN_STDOUT_TO_DEV_NULL,
 865                              SigC::Slot0<void>(),
 866                              0, 0,
 867                              &command_result);
 868             if (command_result != 0)
 869                 throw std::runtime_error("dvdauthor failed");
 870         }
 871     }
 872
 873     void generate_page_dispatch(std::ostream & file, int indent,
 874                                 int first_page, int last_page)
 875     {
 876         if (first_page == 1 && last_page == 1)
 877         {
 878             // The dispatch code is *on* page 1 so we must not dispatch to
 879             // page 1 since that would cause an infinite loop.  This case
 880             // should be unreachable if there is more than one page due
 881             // to the following case.
 882         }
 883         else if (first_page == 1 && last_page == 2)
 884         {
 885             // dvdauthor doesn't allow empty blocks or null statements so
 886             // when selecting between pages 1 and 2 we don't use an "else"
 887             // part.  We must use braces so that a following "else" will
 888             // match the right "if".
 889             file << std::setw(indent) << "" << "{\n"
 890                  << std::setw(indent) << "" << "if (g0 eq 2)\n"
 891                  << std::setw(indent + 2) << "" << "jump menu 2;\n"
 892                  << std::setw(indent) << "" << "}\n";
 893         }
 894         else if (first_page == last_page)
 895         {
 896             file << std::setw(indent) << ""
 897                  << "jump menu " << first_page << ";\n";
 898         }
 899         else
 900         {
 901             int middle = (first_page + last_page) / 2;
 902             file << std::setw(indent) << "" << "if (g0 le " << middle << ")\n";
 903             generate_page_dispatch(file, indent + 2, first_page, middle);
 904             file << std::setw(indent) << "" << "else\n";
 905             generate_page_dispatch(file, indent + 2, middle + 1, last_page);
 906         }
 907     }
 908
 909     const video::frame_params & lookup_frame_params(const char * str)
 910     {
 911         assert(str);
 912         static const struct { const char * str; bool is_ntsc; }
 913         known_strings[] = {
 914             { "NTSC",  true },
 915             { "ntsc",  true },
 916             { "PAL",   false },
 917             { "pal",   false },
 918             // For DVD purposes, SECAM can be treated identically to PAL.
 919             { "SECAM", false },
 920             { "secam", false }
 921         };
 922         for (std::size_t i = 0;
 923              i != sizeof(known_strings)/sizeof(known_strings[0]);
 924              ++i)
 925             if (std::strcmp(str, known_strings[i].str) == 0)
 926                 return known_strings[i].is_ntsc ?
 927                     video::ntsc_params : video::pal_params;
 928         throw std::runtime_error(
 929             std::string("Invalid video standard: ").append(str));
 930     }
 931
 932     void print_usage(std::ostream & stream, const char * command_name)
 933     {
 934         stream << "Usage: " << command_name
 935                << (" [gtk-options] [--video-std std-name]"
 936                    " [--preview] menu-url [output-dir]\n");
 937     }
 938
 939 } // namespace
 940
 941 int main(int argc, char ** argv)
 942 {
 943     try
 944     {
 945         video::frame_params frame_params = video::pal_params;
 946         bool preview_mode = false;
 947         std::string menu_url;
 948         std::string output_dir;
 949
 950         // Do initial option parsing.  We have to do this before
 951         // letting Gtk parse the arguments since we may need to spawn
 952         // Xvfb first.
 953         int argi = 1;
 954         while (argi != argc)
 955         {
 956             if (std::strcmp(argv[argi], "--") == 0)
 957             {
 958                 break;
 959             }
 960             else if (std::strcmp(argv[argi], "--help") == 0)
 961             {
 962                 print_usage(std::cout, argv[0]);
 963                 return EXIT_SUCCESS;
 964             }
 965             else if (std::strcmp(argv[argi], "--preview") == 0)
 966             {
 967                 preview_mode = true;
 968                 argi += 1;
 969             }
 970             else if (std::strcmp(argv[argi], "--video-std") == 0)
 971             {
 972                 if (argi + 1 == argc)
 973                 {
 974                     std::cerr << "Missing argument to --video-std\n";
 975                     print_usage(std::cerr, argv[0]);
 976                     return EXIT_FAILURE;
 977                 }
 978                 frame_params = lookup_frame_params(argv[argi + 1]);
 979                 argi += 2;
 980             }
 981             else
 982             {
 983                 argi += 1;
 984             }
 985         }
 986
 987         std::auto_ptr<FrameBuffer> fb;
 988         if (!preview_mode)
 989         {
 990             // Spawn Xvfb and set env variables so that Xlib will use it
 991             // Use 8 bits each for RGB components, which should translate into
 992             // "enough" bits for YUV components.
 993             fb.reset(new FrameBuffer(frame_params.width, frame_params.height,
 994                                      3 * 8));
 995             setenv("XAUTHORITY", fb->get_x_authority().c_str(), true);
 996             setenv("DISPLAY", fb->get_x_display().c_str(), true);
 997         }
 998
 999         // Initialise Gtk
1000         Gtk::Main kit(argc, argv);
1001
1002         // Complete option parsing with Gtk's options out of the way.
1003         argi = 1;
1004         while (argi != argc)
1005         {
1006             if (std::strcmp(argv[argi], "--") == 0)
1007             {
1008                 argi += 1;
1009                 break;
1010             }
1011             else if (std::strcmp(argv[argi], "--preview") == 0)
1012             {
1013                 argi += 1;
1014             }
1015             else if (std::strcmp(argv[argi], "--video-std") == 0)
1016             {
1017                 argi += 2;
1018             }
1019             else if (argv[argi][0] == '-')
1020             {
1021                 std::cerr << "Invalid option: " << argv[argi] << "\n";
1022                 print_usage(std::cerr, argv[0]);
1023                 return EXIT_FAILURE;
1024             }
1025             else
1026             {
1027                 break;
1028             }
1029         }
1030
1031         // Look for a starting URL or filename and (except in preview
1032         // mode) an output directory after the options.
1033         if (argc - argi != (preview_mode ? 1 : 2))
1034         {
1035             print_usage(std::cerr, argv[0]);
1036             return EXIT_FAILURE;
1037         }
1038         if (std::strstr(argv[argi], "://"))
1039         {
1040             // It appears to be an absolute URL, so use it as-is.
1041             menu_url = argv[argi];
1042         }
1043         else
1044         {
1045             // Assume it's a filename.  Resolve it to an absolute URL.
1046             std::string path(argv[argi]);
1047             if (!Glib::path_is_absolute(path))
1048                 path = Glib::build_filename(Glib::get_current_dir(), path);
1049             menu_url = Glib::filename_to_uri(path);
1050         }
1051         if (!preview_mode)
1052             output_dir = argv[argi + 1];
1053
1054         // Initialise Mozilla
1055         BrowserWidget::init();
1056
1057         // Run the browser/converter
1058         WebDvdWindow window(frame_params, menu_url, output_dir);
1059         Gtk::Main::run(window);
1060     }
1061     catch (std::exception & e)
1062     {
1063         std::cerr << "Fatal error: " << e.what() << "\n";
1064         return EXIT_FAILURE;
1065     }
1066
1067     return EXIT_SUCCESS;
1068 }