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 <nsIPrefBranch.h>
  46 #include <nsIPrefService.h>
  47 #include <nsIPresContext.h>
  48 #include <nsIPresShell.h>
  49 #include <nsIServiceManagerUtils.h>
  50 #include <nsIWebBrowser.h>
  51 #include <nsString.h>
  52
  53 #include "browser_widget.hpp"
  54 #include "child_iterator.hpp"
  55 #include "dvd.hpp"
  56 #include "link_iterator.hpp"
  57 #include "pixbufs.hpp"
  58 #include "style_sheets.hpp"
  59 #include "temp_file.hpp"
  60 #include "video.hpp"
  61 #include "x_frame_buffer.hpp"
  62 #include "xpcom_support.hpp"
  63
  64 using xpcom_support::check;
  65
  66 namespace
  67 {
  68     struct rectangle
  69     {
  70         int left, top;     // inclusive
  71         int right, bottom; // exclusive
  72
  73         rectangle operator|=(const rectangle & other)
  74             {
  75                 if (other.empty())
  76                 {
  77                     // use current extents unchanged
  78                 }
  79                 else if (empty())
  80                 {
  81                     // use other extents
  82                     *this = other;
  83                 }
  84                 else
  85                 {
  86                     // find rectangle enclosing both extents
  87                     left = std::min(left, other.left);
  88                     top = std::min(top, other.top);
  89                     right = std::max(right, other.right);
  90                     bottom = std::max(bottom, other.bottom);
  91                 }
  92
  93                 return *this;
  94             }
  95
  96         rectangle operator&=(const rectangle & other)
  97             {
  98                 // find rectangle enclosed in both extents
  99                 left = std::max(left, other.left);
 100                 top = std::max(top, other.top);
 101                 right = std::max(left, std::min(right, other.right));
 102                 bottom = std::max(top, std::min(bottom, other.bottom));
 103                 return *this;
 104             }
 105
 106         bool empty() const
 107             {
 108                 return left == right || bottom == top;
 109             }
 110     };
 111
 112     rectangle get_elem_rect(nsIDOMNSDocument * ns_doc,
 113                             nsIDOMElement * elem)
 114     {
 115         rectangle result;
 116
 117         // Start with this element's bounding box
 118         nsCOMPtr<nsIBoxObject> box;
 119         check(ns_doc->GetBoxObjectFor(elem, getter_AddRefs(box)));
 120         int width, height;
 121         check(box->GetScreenX(&result.left));
 122         check(box->GetScreenY(&result.top));
 123         check(box->GetWidth(&width));
 124         check(box->GetHeight(&height));
 125         result.right = result.left + width;
 126         result.bottom = result.top + height;
 127
 128         // Merge bounding boxes of all child elements
 129         for (child_iterator it = child_iterator(elem), end; it != end; ++it)
 130         {
 131             nsCOMPtr<nsIDOMNode> child_node(*it);
 132             PRUint16 child_type;
 133             if (check(child_node->GetNodeType(&child_type)),
 134                 child_type == nsIDOMNode::ELEMENT_NODE)
 135             {
 136                 nsCOMPtr<nsIDOMElement> child_elem(
 137                     do_QueryInterface(child_node));
 138                 result |= get_elem_rect(ns_doc, child_elem);
 139             }
 140         }
 141
 142         return result;
 143     }
 144
 145
 146     std::string xml_escape(const std::string & str)
 147     {
 148         std::string result;
 149         std::size_t begin = 0;
 150
 151         for (;;)
 152         {
 153             std::size_t end = str.find_first_of("\"&'<>", begin);
 154             result.append(str, begin, end - begin);
 155             if (end == std::string::npos)
 156                 return result;
 157
 158             const char * entity = NULL;
 159             switch (str[end])
 160             {
 161             case '"':  entity = "&quot;"; break;
 162             case '&':  entity = "&amp;";  break;
 163             case '\'': entity = "&apos;"; break;
 164             case '<':  entity = "&lt;";   break;
 165             case '>':  entity = "&gt;";   break;
 166             }
 167             assert(entity);
 168             result.append(entity);
 169
 170             begin = end + 1;
 171         }
 172     }
 173
 174
 175     struct dvd_contents
 176     {
 177         enum pgc_type { menu_pgc, title_pgc };
 178         typedef std::pair<pgc_type, int> pgc_ref;
 179
 180         struct menu
 181         {
 182             menu()
 183                     : vob_temp(new temp_file("webdvd-vob-"))
 184                 {
 185                     vob_temp->close();
 186                 }
 187
 188             boost::shared_ptr<temp_file> vob_temp;
 189             std::vector<pgc_ref> entries;
 190         };
 191
 192         struct title
 193         {
 194             explicit title(const std::string & vob_list)
 195                     : vob_list(vob_list)
 196                 {}
 197
 198             std::string vob_list;
 199         };
 200
 201         std::vector<menu> menus;
 202         std::vector<title> titles;
 203     };
 204
 205     class webdvd_window : public Gtk::Window
 206     {
 207     public:
 208         webdvd_window(
 209             const video::frame_params & frame_params,
 210             const std::string & main_page_uri,
 211             const std::string & output_dir);
 212
 213     private:
 214         dvd_contents::pgc_ref add_menu(const std::string & uri);
 215         dvd_contents::pgc_ref add_title(const std::string & uri);
 216         void load_next_page();
 217         void on_net_state_change(const char * uri, gint flags, guint status);
 218         bool browser_is_busy() const
 219             {
 220                 return pending_window_update_ || pending_req_count_;
 221             }
 222         bool process_page();
 223         void save_screenshot();
 224         void process_links(nsIPresShell * pres_shell,
 225                            nsIPresContext * pres_context,
 226                            nsIDOMWindow * dom_window);
 227         void generate_dvd();
 228
 229         video::frame_params frame_params_;
 230         std::string output_dir_;
 231         browser_widget browser_widget_;
 232         nsCOMPtr<nsIStyleSheet> stylesheet_;
 233
 234         dvd_contents contents_;
 235         typedef std::map<std::string, dvd_contents::pgc_ref> resource_map_type;
 236         resource_map_type resource_map_;
 237
 238         std::queue<std::string> page_queue_;
 239         bool pending_window_update_;
 240         int pending_req_count_;
 241         bool have_tweaked_page_;
 242         std::auto_ptr<temp_file> background_temp_;
 243         struct page_state;
 244         std::auto_ptr<page_state> page_state_;
 245     };
 246
 247     webdvd_window::webdvd_window(
 248         const video::frame_params & frame_params,
 249         const std::string & main_page_uri,
 250         const std::string & output_dir)
 251             : frame_params_(frame_params),
 252               output_dir_(output_dir),
 253               stylesheet_(load_css("file://" WEBDVD_LIB_DIR "/webdvd.css")),
 254               pending_window_update_(false),
 255               pending_req_count_(0),
 256               have_tweaked_page_(false)
 257     {
 258         set_size_request(frame_params_.width, frame_params_.height);
 259         set_resizable(false);
 260
 261         add(browser_widget_);
 262         browser_widget_.show();
 263         browser_widget_.signal_net_state().connect(
 264             SigC::slot(*this, &webdvd_window::on_net_state_change));
 265
 266         add_menu(main_page_uri);
 267         load_next_page();
 268     }
 269
 270     dvd_contents::pgc_ref webdvd_window::add_menu(const std::string & uri)
 271     {
 272         dvd_contents::pgc_ref next_menu(dvd_contents::menu_pgc,
 273                                         contents_.menus.size());
 274         std::pair<resource_map_type::iterator, bool> insert_result(
 275             resource_map_.insert(std::make_pair(uri, next_menu)));
 276
 277         if (!insert_result.second)
 278         {
 279             return insert_result.first->second;
 280         }
 281         else
 282         {
 283             page_queue_.push(uri);
 284             contents_.menus.resize(contents_.menus.size() + 1);
 285             return next_menu;
 286         }
 287     }
 288
 289     dvd_contents::pgc_ref webdvd_window::add_title(const std::string & uri)
 290     {
 291         dvd_contents::pgc_ref next_title(dvd_contents::title_pgc,
 292                                          contents_.titles.size());
 293         std::pair<resource_map_type::iterator, bool> insert_result(
 294             resource_map_.insert(std::make_pair(uri, next_title)));
 295
 296         if (!insert_result.second)
 297         {
 298             return insert_result.first->second;
 299         }
 300         else
 301         {
 302             Glib::ustring hostname;
 303             std::string filename(Glib::filename_from_uri(uri, hostname));
 304             // FIXME: Should check the hostname
 305
 306             std::string vob_list;
 307
 308             // Store a reference to a linked VOB file, or the contents
 309             // of a linked VOB list file.
 310             if (filename.compare(filename.size() - 4, 4, ".vob") == 0)
 311             {
 312                 if (!Glib::file_test(filename, Glib::FILE_TEST_IS_REGULAR))
 313                     throw std::runtime_error(
 314                         filename + " is missing or not a regular file");
 315                 vob_list
 316                     .append("<vob file='")
 317                     .append(xml_escape(filename))
 318                     .append("'/>\n");
 319             }
 320             else
 321             {
 322                 assert(filename.compare(filename.size() - 8, 8, ".voblist")
 323                        == 0);
 324                 // TODO: Validate the file contents
 325                 vob_list.assign(Glib::file_get_contents(filename));
 326             }
 327
 328             contents_.titles.push_back(dvd_contents::title(vob_list));
 329             return next_title;
 330         }
 331     }
 332
 333     void webdvd_window::load_next_page()
 334     {
 335         assert(!page_queue_.empty());
 336         const std::string & uri = page_queue_.front();
 337         std::cout << "loading " << uri << std::endl;
 338
 339         browser_widget_.load_uri(uri);
 340     }
 341
 342     void webdvd_window::on_net_state_change(const char * uri,
 343                                            gint flags, guint status)
 344     {
 345 #       ifdef DEBUG_ON_NET_STATE_CHANGE
 346         std::cout << "webdvd_window::on_net_state_change(";
 347         if (uri)
 348             std::cout << '"' << uri << '"';
 349         else
 350             std::cout << "NULL";
 351         std::cout << ", ";
 352         {
 353             gint flags_left = flags;
 354             static const struct {
 355                 gint value;
 356                 const char * name;
 357             } flag_names[] = {
 358                 { GTK_MOZ_EMBED_FLAG_START, "STATE_START" },
 359                 { GTK_MOZ_EMBED_FLAG_REDIRECTING, "STATE_REDIRECTING" },
 360                 { GTK_MOZ_EMBED_FLAG_TRANSFERRING, "STATE_TRANSFERRING" },
 361                 { GTK_MOZ_EMBED_FLAG_NEGOTIATING, "STATE_NEGOTIATING" },
 362                 { GTK_MOZ_EMBED_FLAG_STOP, "STATE_STOP" },
 363                 { GTK_MOZ_EMBED_FLAG_IS_REQUEST, "STATE_IS_REQUEST" },
 364                 { GTK_MOZ_EMBED_FLAG_IS_DOCUMENT, "STATE_IS_DOCUMENT" },
 365                 { GTK_MOZ_EMBED_FLAG_IS_NETWORK, "STATE_IS_NETWORK" },
 366                 { GTK_MOZ_EMBED_FLAG_IS_WINDOW, "STATE_IS_WINDOW" }
 367             };
 368             for (int i = 0; i != sizeof(flag_names)/sizeof(flag_names[0]); ++i)
 369             {
 370                 if (flags & flag_names[i].value)
 371                 {
 372                     std::cout << flag_names[i].name;
 373                     flags_left -= flag_names[i].value;
 374                     if (flags_left)
 375                         std::cout << " | ";
 376                 }
 377             }
 378             if (flags_left)
 379                 std::cout << "0x" << std::setbase(16) << flags_left;
 380         }
 381         std::cout << ", " << "0x" << std::setbase(16) << status << ")\n";
 382 #       endif // DEBUG_ON_NET_STATE_CHANGE
 383
 384         if (flags & GTK_MOZ_EMBED_FLAG_IS_REQUEST)
 385         {
 386             if (flags & GTK_MOZ_EMBED_FLAG_START)
 387                 ++pending_req_count_;
 388
 389             if (flags & GTK_MOZ_EMBED_FLAG_STOP)
 390             {
 391                 assert(pending_req_count_ != 0);
 392                 --pending_req_count_;
 393             }
 394         }
 395
 396         if (flags & GTK_MOZ_EMBED_FLAG_IS_DOCUMENT
 397             && flags & GTK_MOZ_EMBED_FLAG_START)
 398         {
 399             pending_window_update_ = true;
 400             have_tweaked_page_ = false;
 401         }
 402
 403         if (flags & GTK_MOZ_EMBED_FLAG_IS_WINDOW
 404             && flags & GTK_MOZ_EMBED_FLAG_STOP)
 405         {
 406             // Check whether the load was successful, ignoring this
 407             // pseudo-error.
 408             if (status != NS_IMAGELIB_ERROR_LOAD_ABORTED)
 409                 check(status);
 410
 411             pending_window_update_ = false;
 412         }
 413
 414         if (!browser_is_busy())
 415         {
 416             try
 417             {
 418                 if (!process_page())
 419                     Gtk::Main::quit();
 420             }
 421             catch (std::exception & e)
 422             {
 423                 std::cerr << "Fatal error";
 424                 if (!page_queue_.empty())
 425                     std::cerr << " while processing <" << page_queue_.front()
 426                               << ">";
 427                 std::cerr << ": " << e.what() << "\n";
 428                 Gtk::Main::quit();
 429             }
 430         }
 431     }
 432
 433     bool webdvd_window::process_page()
 434     {
 435         assert(!page_queue_.empty());
 436
 437         nsCOMPtr<nsIWebBrowser> browser(browser_widget_.get_browser());
 438         nsCOMPtr<nsIDocShell> doc_shell(do_GetInterface(browser));
 439         assert(doc_shell);
 440         nsCOMPtr<nsIPresShell> pres_shell;
 441         check(doc_shell->GetPresShell(getter_AddRefs(pres_shell)));
 442         nsCOMPtr<nsIPresContext> pres_context;
 443         check(doc_shell->GetPresContext(getter_AddRefs(pres_context)));
 444         nsCOMPtr<nsIDOMWindow> dom_window;
 445         check(browser->GetContentDOMWindow(getter_AddRefs(dom_window)));
 446
 447         // If we haven't done so already, apply the stylesheet and
 448         // disable scrollbars.
 449         if (!have_tweaked_page_)
 450         {
 451             apply_style_sheet(stylesheet_, pres_shell);
 452
 453             // This actually only needs to be done once.
 454             nsCOMPtr<nsIDOMBarProp> dom_bar_prop;
 455             check(dom_window->GetScrollbars(getter_AddRefs(dom_bar_prop)));
 456             check(dom_bar_prop->SetVisible(false));
 457
 458             have_tweaked_page_ = true;
 459
 460             // Might need to wait a while for things to load or more
 461             // likely for a re-layout.
 462             if (browser_is_busy())
 463                 return true;
 464         }
 465
 466         // All further work should only be done if we're not in preview mode.
 467         if (!output_dir_.empty())
 468         {
 469             // If we haven't already started work on this menu, save a
 470             // screenshot of its normal appearance.
 471             if (!page_state_.get())
 472                 save_screenshot();
 473
 474             // Start or continue processing links.
 475             process_links(pres_shell, pres_context, dom_window);
 476
 477             // If we've finished work on the links, move on to the
 478             // next page, if any, or else generate the DVD filesystem.
 479             if (!page_state_.get())
 480             {
 481                 page_queue_.pop();
 482                 if (page_queue_.empty())
 483                 {
 484                     generate_dvd();
 485                     return false;
 486                 }
 487                 else
 488                 {
 489                     load_next_page();
 490                 }
 491             }
 492         }
 493
 494         return true;
 495     }
 496
 497     void webdvd_window::save_screenshot()
 498     {
 499         Glib::RefPtr<Gdk::Window> window(get_window());
 500         assert(window);
 501         window->process_updates(true);
 502
 503         background_temp_.reset(new temp_file("webdvd-back-"));
 504         background_temp_->close();
 505         std::cout << "saving " << background_temp_->get_name() << std::endl;
 506         Gdk::Pixbuf::create(Glib::RefPtr<Gdk::Drawable>(window),
 507                             window->get_colormap(),
 508                             0, 0, 0, 0,
 509                             frame_params_.width, frame_params_.height)
 510             ->save(background_temp_->get_name(), "png");
 511     }
 512
 513     struct webdvd_window::page_state
 514     {
 515         page_state(nsIDOMDocument * doc, int width, int height)
 516                 : diff_pixbuf(Gdk::Pixbuf::create(
 517                                   Gdk::COLORSPACE_RGB,
 518                                   true, 8, // has_alpha, bits_per_sample
 519                                   width, height)),
 520                   spumux_temp("webdvd-spumux-"),
 521                   links_temp("webdvd-links-"),
 522                   link_num(0),
 523                   links_it(doc),
 524                   link_changing(false)
 525             {
 526                 spumux_temp.close();
 527                 links_temp.close();
 528             }
 529
 530         Glib::RefPtr<Gdk::Pixbuf> diff_pixbuf;
 531
 532         temp_file spumux_temp;
 533         std::ofstream spumux_file;
 534
 535         temp_file links_temp;
 536
 537         int link_num;
 538         link_iterator links_it, links_end;
 539
 540         rectangle link_rect;
 541         bool link_changing;
 542         Glib::RefPtr<Gdk::Pixbuf> norm_pixbuf;
 543     };
 544
 545     void webdvd_window::process_links(nsIPresShell * pres_shell,
 546                                      nsIPresContext * pres_context,
 547                                      nsIDOMWindow * dom_window)
 548     {
 549         Glib::RefPtr<Gdk::Window> window(get_window());
 550         assert(window);
 551
 552         nsCOMPtr<nsIDOMDocument> basic_doc;
 553         check(dom_window->GetDocument(getter_AddRefs(basic_doc)));
 554         nsCOMPtr<nsIDOMNSDocument> ns_doc(do_QueryInterface(basic_doc));
 555         assert(ns_doc);
 556         nsCOMPtr<nsIEventStateManager> event_state_man(
 557             pres_context->EventStateManager()); // does not AddRef
 558         assert(event_state_man);
 559         nsCOMPtr<nsIDOMDocumentEvent> event_factory(
 560             do_QueryInterface(basic_doc));
 561         assert(event_factory);
 562         nsCOMPtr<nsIDOMDocumentView> doc_view(do_QueryInterface(basic_doc));
 563         assert(doc_view);
 564         nsCOMPtr<nsIDOMAbstractView> view;
 565         check(doc_view->GetDefaultView(getter_AddRefs(view)));
 566
 567         // Set up or recover our iteration state.
 568         std::auto_ptr<page_state> state(page_state_);
 569         if (!state.get())
 570         {
 571             state.reset(
 572                 new page_state(
 573                     basic_doc, frame_params_.width, frame_params_.height));
 574
 575             state->spumux_file.open(state->spumux_temp.get_name().c_str());
 576             state->spumux_file <<
 577                 "<subpictures>\n"
 578                 "  <stream>\n"
 579                 "    <spu force='yes' start='00:00:00.00'\n"
 580                 "        highlight='" << state->links_temp.get_name() << "'\n"
 581                 "        select='" << state->links_temp.get_name() << "'>\n";
 582         }
 583
 584         rectangle window_rect = {
 585             0, 0, frame_params_.width, frame_params_.height
 586         };
 587
 588         int menu_num = resource_map_[page_queue_.front()].second;
 589
 590         for (/* no initialisation */;
 591              state->links_it != state->links_end;
 592              ++state->links_it)
 593         {
 594             nsCOMPtr<nsIDOMNode> node(*state->links_it);
 595
 596             // Find the link URI.
 597             nsCOMPtr<nsILink> link(do_QueryInterface(node));
 598             assert(link);
 599             nsCOMPtr<nsIURI> uri;
 600             check(link->GetHrefURI(getter_AddRefs(uri)));
 601             std::string uri_string;
 602             {
 603                 nsCString uri_ns_string;
 604                 check(uri->GetSpec(uri_ns_string));
 605                 uri_string.assign(uri_ns_string.BeginReading(),
 606                                   uri_ns_string.EndReading());
 607             }
 608             std::string uri_sans_fragment(uri_string, 0, uri_string.find('#'));
 609
 610             // Is this a new link?
 611             if (!state->link_changing)
 612             {
 613                 // Find a rectangle enclosing the link and clip it to the
 614                 // window.
 615                 nsCOMPtr<nsIDOMElement> elem(do_QueryInterface(node));
 616                 assert(elem);
 617                 state->link_rect = get_elem_rect(ns_doc, elem);
 618                 state->link_rect &= window_rect;
 619
 620                 if (state->link_rect.empty())
 621                 {
 622                     std::cerr << "Ignoring invisible link to "
 623                               << uri_string << "\n";
 624                     continue;
 625                 }
 626
 627                 ++state->link_num;
 628
 629                 if (state->link_num >= dvd::menu_buttons_max)
 630                 {
 631                     if (state->link_num == dvd::menu_buttons_max)
 632                         std::cerr << "No more than " << dvd::menu_buttons_max
 633                                   << " buttons can be placed on a menu\n";
 634                     std::cerr << "Ignoring link to " << uri_string << "\n";
 635                     continue;
 636                 }
 637
 638                 state->spumux_file <<
 639                     "      <button x0='" << state->link_rect.left << "'"
 640                     " y0='" << state->link_rect.top << "'"
 641                     " x1='" << state->link_rect.right - 1 << "'"
 642                     " y1='" << state->link_rect.bottom - 1 << "'/>\n";
 643
 644                 // Check whether this is a link to a video or a page then
 645                 // add it to the known resources if not already seen; then
 646                 // add it to the menu entries.
 647                 nsCString path;
 648                 check(uri->GetPath(path));
 649                 dvd_contents::pgc_ref dest_pgc;
 650                 // FIXME: This is a bit of a hack.  Perhaps we could decide
 651                 // later based on the MIME type determined by Mozilla?
 652                 if ((path.Length() > 4
 653                      && std::strcmp(path.EndReading() - 4, ".vob") == 0)
 654                     || (path.Length() > 8
 655                         && std::strcmp(path.EndReading() - 8, ".voblist")
 656                            == 0))
 657                 {
 658                     PRBool is_file;
 659                     check(uri->SchemeIs("file", &is_file));
 660                     if (!is_file)
 661                     {
 662                         std::cerr << "Links to video must use the file:"
 663                                   << " scheme\n";
 664                         continue;
 665                     }
 666                     dest_pgc = add_title(uri_sans_fragment);
 667                 }
 668                 else
 669                 {
 670                     dest_pgc = add_menu(uri_sans_fragment);
 671                 }
 672                 contents_.menus[menu_num].entries.push_back(dest_pgc);
 673
 674                 nsCOMPtr<nsIContent> content(do_QueryInterface(node));
 675                 assert(content);
 676                 nsCOMPtr<nsIDOMEventTarget> event_target(
 677                     do_QueryInterface(node));
 678                 assert(event_target);
 679
 680                 state->norm_pixbuf = Gdk::Pixbuf::create(
 681                     Glib::RefPtr<Gdk::Drawable>(window),
 682                     window->get_colormap(),
 683                     state->link_rect.left,
 684                     state->link_rect.top,
 685                     0,
 686                     0,
 687                     state->link_rect.right - state->link_rect.left,
 688                     state->link_rect.bottom - state->link_rect.top);
 689
 690                 nsCOMPtr<nsIDOMEvent> event;
 691                 check(event_factory->CreateEvent(
 692                           NS_ConvertASCIItoUTF16("MouseEvents"),
 693                           getter_AddRefs(event)));
 694                 nsCOMPtr<nsIDOMMouseEvent> mouse_event(
 695                     do_QueryInterface(event));
 696                 assert(mouse_event);
 697                 check(mouse_event->InitMouseEvent(
 698                           NS_ConvertASCIItoUTF16("mouseover"),
 699                           true,  // can bubble
 700                           true,  // cancelable
 701                           view,
 702                           0,     // detail: mouse click count
 703                           state->link_rect.left, // screenX
 704                           state->link_rect.top,  // screenY
 705                           state->link_rect.left, // clientX
 706                           state->link_rect.top,  // clientY
 707                           false, false, false, false, // qualifiers
 708                           0,     // button: left (or primary)
 709                           0));   // related target
 710                 PRBool dummy;
 711                 check(event_target->DispatchEvent(mouse_event,
 712                                                   &dummy));
 713                 check(event_state_man->SetContentState(content,
 714                                                        NS_EVENT_STATE_HOVER));
 715
 716                 pres_shell->FlushPendingNotifications(true);
 717
 718                 // We may have to exit and wait for image loading
 719                 // to complete, at which point we will be called
 720                 // again.
 721                 if (browser_is_busy())
 722                 {
 723                     state->link_changing = true;
 724                     page_state_ = state;
 725                     return;
 726                 }
 727             }
 728
 729             window->process_updates(true);
 730
 731             Glib::RefPtr<Gdk::Pixbuf> changed_pixbuf(
 732                 Gdk::Pixbuf::create(
 733                     Glib::RefPtr<Gdk::Drawable>(window),
 734                     window->get_colormap(),
 735                     state->link_rect.left,
 736                     state->link_rect.top,
 737                     0,
 738                     0,
 739                     state->link_rect.right - state->link_rect.left,
 740                     state->link_rect.bottom - state->link_rect.top));
 741             diff_rgb_pixbufs(
 742                 state->norm_pixbuf,
 743                 changed_pixbuf,
 744                 state->diff_pixbuf,
 745                 state->link_rect.left,
 746                 state->link_rect.top,
 747                 state->link_rect.right - state->link_rect.left,
 748                 state->link_rect.bottom - state->link_rect.top);
 749         }
 750
 751         quantise_rgba_pixbuf(state->diff_pixbuf, dvd::button_n_colours);
 752
 753         std::cout << "saving " << state->links_temp.get_name()
 754                   << std::endl;
 755         state->diff_pixbuf->save(state->links_temp.get_name(), "png");
 756
 757         state->spumux_file <<
 758             "    </spu>\n"
 759             "  </stream>\n"
 760             "</subpictures>\n";
 761
 762         state->spumux_file.close();
 763
 764         // TODO: if (!state->spumux_file) throw ...
 765
 766         {
 767             std::ostringstream command_stream;
 768             command_stream << "pngtopnm "
 769                            << background_temp_->get_name()
 770                            << " | ppmtoy4m -v0 -n1 -F"
 771                            << frame_params_.rate_numer
 772                            << ":" << frame_params_.rate_denom
 773                            << " -A" << frame_params_.pixel_ratio_width
 774                            << ":" << frame_params_.pixel_ratio_height
 775                            << (" -Ip -S420_mpeg2"
 776                                " | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
 777                                " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
 778                                " | spumux -v0 -mdvd ")
 779                            << state->spumux_temp.get_name()
 780                            << " > "
 781                            << contents_.menus[menu_num].vob_temp->get_name();
 782             std::string command(command_stream.str());
 783             const char * argv[] = {
 784                 "/bin/sh", "-c", command.c_str(), 0
 785             };
 786             std::cout << "running " << argv[2] << std::endl;
 787             int command_result;
 788             Glib::spawn_sync(".",
 789                              Glib::ArrayHandle<std::string>(
 790                                  argv, sizeof(argv)/sizeof(argv[0]),
 791                                  Glib::OWNERSHIP_NONE),
 792                              Glib::SPAWN_STDOUT_TO_DEV_NULL,
 793                              SigC::Slot0<void>(),
 794                              0, 0,
 795                              &command_result);
 796             if (command_result != 0)
 797                 throw std::runtime_error("spumux pipeline failed");
 798         }
 799     }
 800
 801     void webdvd_window::generate_dvd()
 802     {
 803         temp_file temp("webdvd-dvdauthor-");
 804         temp.close();
 805         std::ofstream file(temp.get_name().c_str());
 806
 807         // We generate code that uses registers in the following way:
 808         //
 809         // g0:     scratch
 810         // g1:     current location
 811         // g12:    location that last jumped to a video
 812         //
 813         // All locations are divided into two bitfields: the least
 814         // significant 10 bits are a page/menu number and the most
 815         // significant 6 bits are a link/button number, and numbering
 816         // starts at 1, not 0.  This is done for compatibility with
 817         // the encoding of the s8 (button) register.
 818         //
 819         static const int button_mult = dvd::reg_s8_button_mult;
 820         static const int menu_mask = button_mult - 1;
 821         static const int button_mask = (1 << dvd::reg_bits) - button_mult;
 822
 823         file <<
 824             "<dvdauthor>\n"
 825             "  <vmgm>\n"
 826             "    <menus>\n";
 827
 828         for (std::size_t menu_num = 0;
 829              menu_num != contents_.menus.size();
 830              ++menu_num)
 831         {
 832             dvd_contents::menu & menu = contents_.menus[menu_num];
 833
 834             if (menu_num == 0)
 835             {
 836                 // This is the first (title) menu, displayed when the
 837                 // disc is first played.
 838                 file <<
 839                     "      <pgc entry='title'>\n"
 840                     "        <pre>\n"
 841                     // Initialise the current location if it is not set
 842                     // (all general registers are initially 0).
 843                     "          if (g1 eq 0)\n"
 844                     "            g1 = " << 1 + button_mult << ";\n";
 845             }
 846             else
 847             {
 848                 file <<
 849                     "      <pgc>\n"
 850                     "        <pre>\n";
 851             }
 852
 853             // When a title finishes or the user presses the menu
 854             // button, this always jumps to the titleset's root menu.
 855             // We want to return the user to the last menu they used.
 856             // So we arrange for each titleset's root menu to return
 857             // to the vmgm title menu and then dispatch from there to
 858             // whatever the correct menu is.  We determine the correct
 859             // menu by looking at the menu part of g1.
 860
 861             file << "          g0 = g1 &amp; " << menu_mask << ";\n";
 862
 863             // There is a limit of 128 VM instructions in each PGC.
 864             // Therefore in each menu's <pre> section we generate
 865             // jumps to menus with numbers greater by 512, 256, 128,
 866             // ..., 1 where (a) such a menu exists, (b) this menu
 867             // number is divisible by twice that increment and (c) the
 868             // correct menu is that or a later menu.  Thus each menu
 869             // has at most 10 such conditional jumps and is reachable
 870             // by at most 10 jumps from the title menu.  This chain of
 871             // jumps might take too long on some players; this has yet
 872             // to be investigated.
 873
 874             for (std::size_t menu_incr = (menu_mask + 1) / 2;
 875                  menu_incr != 0;
 876                  menu_incr /= 2)
 877             {
 878                 if (menu_num + menu_incr < contents_.menus.size()
 879                     && (menu_num & (menu_incr * 2 - 1)) == 0)
 880                 {
 881                     file <<
 882                         "          if (g0 ge " << 1 + menu_num + menu_incr
 883                                                << ")\n"
 884                         "            jump menu " << 1 + menu_num + menu_incr
 885                                                << ";\n";
 886                 }
 887             }
 888
 889             file <<
 890                 // Highlight the appropriate button.
 891                 "          s8 = g1 &amp; " << button_mask << ";\n"
 892                 "        </pre>\n"
 893                 "        <vob file='" << menu.vob_temp->get_name() << "'/>\n";
 894
 895             for (std::size_t button_num = 0;
 896                  button_num != menu.entries.size();
 897                  ++button_num)
 898             {
 899                 file << "        <button> ";
 900
 901                 if (menu.entries[button_num].first == dvd_contents::menu_pgc)
 902                 {
 903                     int dest_menu_num = menu.entries[button_num].second;
 904
 905                     // Look for a button on the new menu that links
 906                     // back to this one.  If there is one, set that to
 907                     // be the highlighted button; otherwise, use the
 908                     // first button.
 909                     const std::vector<dvd_contents::pgc_ref> &
 910                         dest_menu_entries =
 911                         contents_.menus[dest_menu_num].entries;
 912                     dvd_contents::pgc_ref this_pgc(
 913                         dvd_contents::menu_pgc, menu_num);
 914                     std::size_t dest_button_num = dest_menu_entries.size();
 915                     while (dest_button_num != 0
 916                            && dest_menu_entries[--dest_button_num] != this_pgc)
 917                         ;
 918
 919                     file << "g1 = "
 920                          << (1 + dest_menu_num
 921                              + (1 + dest_button_num) * button_mult)
 922                          << "; jump menu " << 1 + dest_menu_num << ";";
 923                 }
 924                 else
 925                 {
 926                     assert(menu.entries[button_num].first
 927                            == dvd_contents::title_pgc);
 928
 929                     file << "g1 = "
 930                          << 1 + menu_num + (1 + button_num) * button_mult
 931                          << "; jump title "
 932                          << 1 + menu.entries[button_num].second << ";";
 933                 }
 934
 935                 file <<  " </button>\n";
 936             }
 937
 938             file << "      </pgc>\n";
 939         }
 940
 941         file <<
 942             "    </menus>\n"
 943             "  </vmgm>\n";
 944
 945         // Generate a titleset for each title.  This appears to make
 946         // jumping to titles a whole lot simpler (but limits us to 99
 947         // titles).
 948         for (std::size_t title_num = 0;
 949              title_num != contents_.titles.size();
 950              ++title_num)
 951         {
 952             file <<
 953                 "  <titleset>\n"
 954                 // Generate a dummy menu so that the menu button on the
 955                 // remote control will work.
 956                 "    <menus>\n"
 957                 "      <pgc entry='root'>\n"
 958                 "        <pre> jump vmgm menu; </pre>\n"
 959                 "      </pgc>\n"
 960                 "    </menus>\n"
 961                 "    <titles>\n"
 962                 "      <pgc>\n"
 963                 // Record calling location.
 964                 "        <pre> g12 = g1; </pre>\n"
 965                  << contents_.titles[title_num].vob_list <<
 966                 // If the menu location has not been changed during
 967                 // the title, set the location to be the following
 968                 // button in the menu.  In any case, return to some
 969                 // menu.
 970                 "        <post> if (g1 eq g12) g1 = g1 + " << button_mult
 971                  << "; call menu; </post>\n"
 972                 "      </pgc>\n"
 973                 "    </titles>\n"
 974                 "  </titleset>\n";
 975         }
 976
 977         file <<
 978             "</dvdauthor>\n";
 979
 980         file.close();
 981
 982         {
 983             const char * argv[] = {
 984                 "dvdauthor",
 985                 "-o", output_dir_.c_str(),
 986                 "-x", temp.get_name().c_str(),
 987                 0
 988             };
 989             int command_result;
 990             Glib::spawn_sync(".",
 991                              Glib::ArrayHandle<std::string>(
 992                                  argv, sizeof(argv)/sizeof(argv[0]),
 993                                  Glib::OWNERSHIP_NONE),
 994                              Glib::SPAWN_SEARCH_PATH
 995                              | Glib::SPAWN_STDOUT_TO_DEV_NULL,
 996                              SigC::Slot0<void>(),
 997                              0, 0,
 998                              &command_result);
 999             if (command_result != 0)
1000                 throw std::runtime_error("dvdauthor failed");
1001         }
1002     }
1003
1004     const video::frame_params & lookup_frame_params(const char * str)
1005     {
1006         assert(str);
1007         static const struct { const char * str; bool is_ntsc; }
1008         known_strings[] = {
1009             { "NTSC",  true },
1010             { "ntsc",  true },
1011             { "PAL",   false },
1012             { "pal",   false },
1013             // For DVD purposes, SECAM can be treated identically to PAL.
1014             { "SECAM", false },
1015             { "secam", false }
1016         };
1017         for (std::size_t i = 0;
1018              i != sizeof(known_strings)/sizeof(known_strings[0]);
1019              ++i)
1020             if (std::strcmp(str, known_strings[i].str) == 0)
1021                 return known_strings[i].is_ntsc ?
1022                     video::ntsc_params : video::pal_params;
1023         throw std::runtime_error(
1024             std::string("Invalid video standard: ").append(str));
1025     }
1026
1027     void print_usage(std::ostream & stream, const char * command_name)
1028     {
1029         stream << "Usage: " << command_name
1030                << (" [gtk-options] [--video-std std-name]"
1031                    " [--preview] menu-url [output-dir]\n");
1032     }
1033
1034     void set_browser_preferences()
1035     {
1036         nsCOMPtr<nsIPrefService> pref_service;
1037         static const nsCID pref_service_cid = NS_PREFSERVICE_CID;
1038         check(CallGetService<nsIPrefService>(pref_service_cid,
1039                                              getter_AddRefs(pref_service)));
1040         nsCOMPtr<nsIPrefBranch> pref_branch;
1041
1042         // Disable IE-compatibility kluge that causes backgrounds to
1043         // sometimes/usually be missing from snapshots.  This is only
1044         // effective from Mozilla 1.8 onward.
1045 #       if MOZ_VERSION_MAJOR > 1                                 \
1046            || (MOZ_VERSION_MAJOR == 1 && MOZ_VERSION_MINOR >= 8)
1047         check(pref_service->GetDefaultBranch("layout",
1048                                              getter_AddRefs(pref_branch)));
1049         check(pref_branch->SetBoolPref(
1050                   "fire_onload_after_image_background_loads",
1051                   true));
1052 #       endif
1053
1054         // Set display resolution.  With standard-definition video we
1055         // will be fitting ~600 pixels across a screen typically
1056         // ranging from 10 to 25 inches wide, for a resolution of
1057         // 24-60 dpi.  I therefore declare the average horizontal
1058         // resolution to be 40 dpi.  The vertical resolution will be
1059         // slightly higher (PAL/SECAM) or lower (NTSC), but
1060         // unfortunately Mozilla doesn't support non-square pixels
1061         // (and neither do fontconfig or Xft anyway).
1062         check(pref_service->GetDefaultBranch("browser.display",
1063                                              getter_AddRefs(pref_branch)));
1064         check(pref_branch->SetIntPref("screen_resolution", 40));
1065     }
1066
1067 } // namespace
1068
1069 int main(int argc, char ** argv)
1070 {
1071     try
1072     {
1073         video::frame_params frame_params = video::pal_params;
1074         bool preview_mode = false;
1075         std::string menu_url;
1076         std::string output_dir;
1077
1078         // Do initial option parsing.  We have to do this before
1079         // letting Gtk parse the arguments since we may need to spawn
1080         // Xvfb first.
1081         int argi = 1;
1082         while (argi != argc)
1083         {
1084             if (std::strcmp(argv[argi], "--") == 0)
1085             {
1086                 break;
1087             }
1088             else if (std::strcmp(argv[argi], "--help") == 0)
1089             {
1090                 print_usage(std::cout, argv[0]);
1091                 return EXIT_SUCCESS;
1092             }
1093             else if (std::strcmp(argv[argi], "--preview") == 0)
1094             {
1095                 preview_mode = true;
1096                 argi += 1;
1097             }
1098             else if (std::strcmp(argv[argi], "--video-std") == 0)
1099             {
1100                 if (argi + 1 == argc)
1101                 {
1102                     std::cerr << "Missing argument to --video-std\n";
1103                     print_usage(std::cerr, argv[0]);
1104                     return EXIT_FAILURE;
1105                 }
1106                 frame_params = lookup_frame_params(argv[argi + 1]);
1107                 argi += 2;
1108             }
1109             else
1110             {
1111                 argi += 1;
1112             }
1113         }
1114
1115         std::auto_ptr<x_frame_buffer> fb;
1116         if (!preview_mode)
1117         {
1118             // Spawn Xvfb and set env variables so that Xlib will use it
1119             // Use 8 bits each for RGB components, which should translate into
1120             // "enough" bits for YUV components.
1121             fb.reset(new x_frame_buffer(frame_params.width,
1122                                         frame_params.height,
1123                                         3 * 8));
1124             setenv("XAUTHORITY", fb->get_authority().c_str(), true);
1125             setenv("DISPLAY", fb->get_display().c_str(), true);
1126         }
1127
1128         // Initialise Gtk
1129         Gtk::Main kit(argc, argv);
1130
1131         // Complete option parsing with Gtk's options out of the way.
1132         argi = 1;
1133         while (argi != argc)
1134         {
1135             if (std::strcmp(argv[argi], "--") == 0)
1136             {
1137                 argi += 1;
1138                 break;
1139             }
1140             else if (std::strcmp(argv[argi], "--preview") == 0)
1141             {
1142                 argi += 1;
1143             }
1144             else if (std::strcmp(argv[argi], "--video-std") == 0)
1145             {
1146                 argi += 2;
1147             }
1148             else if (argv[argi][0] == '-')
1149             {
1150                 std::cerr << "Invalid option: " << argv[argi] << "\n";
1151                 print_usage(std::cerr, argv[0]);
1152                 return EXIT_FAILURE;
1153             }
1154             else
1155             {
1156                 break;
1157             }
1158         }
1159
1160         // Look for a starting URL or filename and (except in preview
1161         // mode) an output directory after the options.
1162         if (argc - argi != (preview_mode ? 1 : 2))
1163         {
1164             print_usage(std::cerr, argv[0]);
1165             return EXIT_FAILURE;
1166         }
1167         if (std::strstr(argv[argi], "://"))
1168         {
1169             // It appears to be an absolute URL, so use it as-is.
1170             menu_url = argv[argi];
1171         }
1172         else
1173         {
1174             // Assume it's a filename.  Resolve it to an absolute URL.
1175             std::string path(argv[argi]);
1176             if (!Glib::path_is_absolute(path))
1177                 path = Glib::build_filename(Glib::get_current_dir(), path);
1178             menu_url = Glib::filename_to_uri(path);
1179         }
1180         if (!preview_mode)
1181             output_dir = argv[argi + 1];
1182
1183         // Initialise Mozilla
1184         browser_widget::initialiser browser_init;
1185         set_browser_preferences();
1186
1187         // Run the browser/converter
1188         webdvd_window window(frame_params, menu_url, output_dir);
1189         Gtk::Main::run(window);
1190     }
1191     catch (std::exception & e)
1192     {
1193         std::cerr << "Fatal error: " << e.what() << "\n";
1194         return EXIT_FAILURE;
1195     }
1196
1197     return EXIT_SUCCESS;
1198 }