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     void generate_dvd(const dvd_contents & contents,
 206                       const std::string & output_dir);
 207
 208     class webdvd_window : public Gtk::Window
 209     {
 210     public:
 211         webdvd_window(
 212             const video::frame_params & frame_params,
 213             const std::string & main_page_uri,
 214             const std::string & output_dir);
 215
 216     private:
 217         dvd_contents::pgc_ref add_menu(const std::string & uri);
 218         dvd_contents::pgc_ref add_title(const std::string & uri);
 219         void load_next_page();
 220         void on_net_state_change(const char * uri, gint flags, guint status);
 221         bool browser_is_busy() const
 222             {
 223                 return pending_window_update_ || pending_req_count_;
 224             }
 225         bool process_page();
 226         void save_screenshot();
 227         void process_links(nsIPresShell * pres_shell,
 228                            nsIPresContext * pres_context,
 229                            nsIDOMWindow * dom_window);
 230
 231         video::frame_params frame_params_;
 232         std::string output_dir_;
 233         browser_widget browser_widget_;
 234         nsCOMPtr<nsIStyleSheet> stylesheet_;
 235
 236         dvd_contents contents_;
 237         typedef std::map<std::string, dvd_contents::pgc_ref> resource_map_type;
 238         resource_map_type resource_map_;
 239
 240         std::queue<std::string> page_queue_;
 241         bool pending_window_update_;
 242         int pending_req_count_;
 243         bool have_tweaked_page_;
 244         std::auto_ptr<temp_file> background_temp_;
 245         struct page_state;
 246         std::auto_ptr<page_state> page_state_;
 247     };
 248
 249     webdvd_window::webdvd_window(
 250         const video::frame_params & frame_params,
 251         const std::string & main_page_uri,
 252         const std::string & output_dir)
 253             : frame_params_(frame_params),
 254               output_dir_(output_dir),
 255               stylesheet_(load_css("file://" WEBDVD_LIB_DIR "/webdvd.css")),
 256               pending_window_update_(false),
 257               pending_req_count_(0),
 258               have_tweaked_page_(false)
 259     {
 260         set_size_request(frame_params_.width, frame_params_.height);
 261         set_resizable(false);
 262
 263         add(browser_widget_);
 264         browser_widget_.show();
 265         browser_widget_.signal_net_state().connect(
 266             SigC::slot(*this, &webdvd_window::on_net_state_change));
 267
 268         add_menu(main_page_uri);
 269         load_next_page();
 270     }
 271
 272     dvd_contents::pgc_ref webdvd_window::add_menu(const std::string & uri)
 273     {
 274         dvd_contents::pgc_ref next_menu(dvd_contents::menu_pgc,
 275                                         contents_.menus.size());
 276         std::pair<resource_map_type::iterator, bool> insert_result(
 277             resource_map_.insert(std::make_pair(uri, next_menu)));
 278
 279         if (!insert_result.second)
 280         {
 281             return insert_result.first->second;
 282         }
 283         else
 284         {
 285             page_queue_.push(uri);
 286             contents_.menus.resize(contents_.menus.size() + 1);
 287             return next_menu;
 288         }
 289     }
 290
 291     dvd_contents::pgc_ref webdvd_window::add_title(const std::string & uri)
 292     {
 293         dvd_contents::pgc_ref next_title(dvd_contents::title_pgc,
 294                                          contents_.titles.size());
 295         std::pair<resource_map_type::iterator, bool> insert_result(
 296             resource_map_.insert(std::make_pair(uri, next_title)));
 297
 298         if (!insert_result.second)
 299         {
 300             return insert_result.first->second;
 301         }
 302         else
 303         {
 304             Glib::ustring hostname;
 305             std::string filename(Glib::filename_from_uri(uri, hostname));
 306             // FIXME: Should check the hostname
 307
 308             std::string vob_list;
 309
 310             // Store a reference to a linked VOB file, or the contents
 311             // of a linked VOB list file.
 312             if (filename.compare(filename.size() - 4, 4, ".vob") == 0)
 313             {
 314                 if (!Glib::file_test(filename, Glib::FILE_TEST_IS_REGULAR))
 315                     throw std::runtime_error(
 316                         filename + " is missing or not a regular file");
 317                 vob_list
 318                     .append("<vob file='")
 319                     .append(xml_escape(filename))
 320                     .append("'/>\n");
 321             }
 322             else
 323             {
 324                 assert(filename.compare(filename.size() - 8, 8, ".voblist")
 325                        == 0);
 326                 // TODO: Validate the file contents
 327                 vob_list.assign(Glib::file_get_contents(filename));
 328             }
 329
 330             contents_.titles.push_back(dvd_contents::title(vob_list));
 331             return next_title;
 332         }
 333     }
 334
 335     void webdvd_window::load_next_page()
 336     {
 337         assert(!page_queue_.empty());
 338         const std::string & uri = page_queue_.front();
 339         std::cout << "loading " << uri << std::endl;
 340
 341         browser_widget_.load_uri(uri);
 342     }
 343
 344     void webdvd_window::on_net_state_change(const char * uri,
 345                                            gint flags, guint status)
 346     {
 347 #       ifdef DEBUG_ON_NET_STATE_CHANGE
 348         std::cout << "webdvd_window::on_net_state_change(";
 349         if (uri)
 350             std::cout << '"' << uri << '"';
 351         else
 352             std::cout << "NULL";
 353         std::cout << ", ";
 354         {
 355             gint flags_left = flags;
 356             static const struct {
 357                 gint value;
 358                 const char * name;
 359             } flag_names[] = {
 360                 { GTK_MOZ_EMBED_FLAG_START, "STATE_START" },
 361                 { GTK_MOZ_EMBED_FLAG_REDIRECTING, "STATE_REDIRECTING" },
 362                 { GTK_MOZ_EMBED_FLAG_TRANSFERRING, "STATE_TRANSFERRING" },
 363                 { GTK_MOZ_EMBED_FLAG_NEGOTIATING, "STATE_NEGOTIATING" },
 364                 { GTK_MOZ_EMBED_FLAG_STOP, "STATE_STOP" },
 365                 { GTK_MOZ_EMBED_FLAG_IS_REQUEST, "STATE_IS_REQUEST" },
 366                 { GTK_MOZ_EMBED_FLAG_IS_DOCUMENT, "STATE_IS_DOCUMENT" },
 367                 { GTK_MOZ_EMBED_FLAG_IS_NETWORK, "STATE_IS_NETWORK" },
 368                 { GTK_MOZ_EMBED_FLAG_IS_WINDOW, "STATE_IS_WINDOW" }
 369             };
 370             for (int i = 0; i != sizeof(flag_names)/sizeof(flag_names[0]); ++i)
 371             {
 372                 if (flags & flag_names[i].value)
 373                 {
 374                     std::cout << flag_names[i].name;
 375                     flags_left -= flag_names[i].value;
 376                     if (flags_left)
 377                         std::cout << " | ";
 378                 }
 379             }
 380             if (flags_left)
 381                 std::cout << "0x" << std::setbase(16) << flags_left;
 382         }
 383         std::cout << ", " << "0x" << std::setbase(16) << status << ")\n";
 384 #       endif // DEBUG_ON_NET_STATE_CHANGE
 385
 386         if (flags & GTK_MOZ_EMBED_FLAG_IS_REQUEST)
 387         {
 388             if (flags & GTK_MOZ_EMBED_FLAG_START)
 389                 ++pending_req_count_;
 390
 391             if (flags & GTK_MOZ_EMBED_FLAG_STOP)
 392             {
 393                 assert(pending_req_count_ != 0);
 394                 --pending_req_count_;
 395             }
 396         }
 397
 398         if (flags & GTK_MOZ_EMBED_FLAG_IS_DOCUMENT
 399             && flags & GTK_MOZ_EMBED_FLAG_START)
 400         {
 401             pending_window_update_ = true;
 402             have_tweaked_page_ = false;
 403         }
 404
 405         if (flags & GTK_MOZ_EMBED_FLAG_IS_WINDOW
 406             && flags & GTK_MOZ_EMBED_FLAG_STOP)
 407         {
 408             // Check whether the load was successful, ignoring this
 409             // pseudo-error.
 410             if (status != NS_IMAGELIB_ERROR_LOAD_ABORTED)
 411                 check(status);
 412
 413             pending_window_update_ = false;
 414         }
 415
 416         if (!browser_is_busy())
 417         {
 418             try
 419             {
 420                 if (!process_page())
 421                     Gtk::Main::quit();
 422             }
 423             catch (std::exception & e)
 424             {
 425                 std::cerr << "Fatal error";
 426                 if (!page_queue_.empty())
 427                     std::cerr << " while processing <" << page_queue_.front()
 428                               << ">";
 429                 std::cerr << ": " << e.what() << "\n";
 430                 Gtk::Main::quit();
 431             }
 432         }
 433     }
 434
 435     bool webdvd_window::process_page()
 436     {
 437         assert(!page_queue_.empty());
 438
 439         nsCOMPtr<nsIWebBrowser> browser(browser_widget_.get_browser());
 440         nsCOMPtr<nsIDocShell> doc_shell(do_GetInterface(browser));
 441         assert(doc_shell);
 442         nsCOMPtr<nsIPresShell> pres_shell;
 443         check(doc_shell->GetPresShell(getter_AddRefs(pres_shell)));
 444         nsCOMPtr<nsIPresContext> pres_context;
 445         check(doc_shell->GetPresContext(getter_AddRefs(pres_context)));
 446         nsCOMPtr<nsIDOMWindow> dom_window;
 447         check(browser->GetContentDOMWindow(getter_AddRefs(dom_window)));
 448
 449         // If we haven't done so already, apply the stylesheet and
 450         // disable scrollbars.
 451         if (!have_tweaked_page_)
 452         {
 453             apply_style_sheet(stylesheet_, pres_shell);
 454
 455             // This actually only needs to be done once.
 456             nsCOMPtr<nsIDOMBarProp> dom_bar_prop;
 457             check(dom_window->GetScrollbars(getter_AddRefs(dom_bar_prop)));
 458             check(dom_bar_prop->SetVisible(false));
 459
 460             have_tweaked_page_ = true;
 461
 462             // Might need to wait a while for things to load or more
 463             // likely for a re-layout.
 464             if (browser_is_busy())
 465                 return true;
 466         }
 467
 468         // All further work should only be done if we're not in preview mode.
 469         if (!output_dir_.empty())
 470         {
 471             // If we haven't already started work on this menu, save a
 472             // screenshot of its normal appearance.
 473             if (!page_state_.get())
 474                 save_screenshot();
 475
 476             // Start or continue processing links.
 477             process_links(pres_shell, pres_context, dom_window);
 478
 479             // If we've finished work on the links, move on to the
 480             // next page, if any, or else generate the DVD filesystem.
 481             if (!page_state_.get())
 482             {
 483                 page_queue_.pop();
 484                 if (page_queue_.empty())
 485                 {
 486                     generate_dvd(contents_, output_dir_);
 487                     return false;
 488                 }
 489                 else
 490                 {
 491                     load_next_page();
 492                 }
 493             }
 494         }
 495
 496         return true;
 497     }
 498
 499     void webdvd_window::save_screenshot()
 500     {
 501         Glib::RefPtr<Gdk::Window> window(get_window());
 502         assert(window);
 503         window->process_updates(true);
 504
 505         background_temp_.reset(new temp_file("webdvd-back-"));
 506         background_temp_->close();
 507         std::cout << "saving " << background_temp_->get_name() << std::endl;
 508         Gdk::Pixbuf::create(Glib::RefPtr<Gdk::Drawable>(window),
 509                             window->get_colormap(),
 510                             0, 0, 0, 0,
 511                             frame_params_.width, frame_params_.height)
 512             ->save(background_temp_->get_name(), "png");
 513     }
 514
 515     struct webdvd_window::page_state
 516     {
 517         page_state(nsIDOMDocument * doc, int width, int height)
 518                 : diff_pixbuf(Gdk::Pixbuf::create(
 519                                   Gdk::COLORSPACE_RGB,
 520                                   true, 8, // has_alpha, bits_per_sample
 521                                   width, height)),
 522                   spumux_temp("webdvd-spumux-"),
 523                   links_temp("webdvd-links-"),
 524                   link_num(0),
 525                   links_it(doc),
 526                   link_changing(false)
 527             {
 528                 spumux_temp.close();
 529                 links_temp.close();
 530             }
 531
 532         Glib::RefPtr<Gdk::Pixbuf> diff_pixbuf;
 533
 534         temp_file spumux_temp;
 535         std::ofstream spumux_file;
 536
 537         temp_file links_temp;
 538
 539         int link_num;
 540         link_iterator links_it, links_end;
 541
 542         rectangle link_rect;
 543         bool link_changing;
 544         Glib::RefPtr<Gdk::Pixbuf> norm_pixbuf;
 545     };
 546
 547     void webdvd_window::process_links(nsIPresShell * pres_shell,
 548                                      nsIPresContext * pres_context,
 549                                      nsIDOMWindow * dom_window)
 550     {
 551         Glib::RefPtr<Gdk::Window> window(get_window());
 552         assert(window);
 553
 554         nsCOMPtr<nsIDOMDocument> basic_doc;
 555         check(dom_window->GetDocument(getter_AddRefs(basic_doc)));
 556         nsCOMPtr<nsIDOMNSDocument> ns_doc(do_QueryInterface(basic_doc));
 557         assert(ns_doc);
 558         nsCOMPtr<nsIEventStateManager> event_state_man(
 559             pres_context->EventStateManager()); // does not AddRef
 560         assert(event_state_man);
 561         nsCOMPtr<nsIDOMDocumentEvent> event_factory(
 562             do_QueryInterface(basic_doc));
 563         assert(event_factory);
 564         nsCOMPtr<nsIDOMDocumentView> doc_view(do_QueryInterface(basic_doc));
 565         assert(doc_view);
 566         nsCOMPtr<nsIDOMAbstractView> view;
 567         check(doc_view->GetDefaultView(getter_AddRefs(view)));
 568
 569         // Set up or recover our iteration state.
 570         std::auto_ptr<page_state> state(page_state_);
 571         if (!state.get())
 572         {
 573             state.reset(
 574                 new page_state(
 575                     basic_doc, frame_params_.width, frame_params_.height));
 576
 577             state->spumux_file.open(state->spumux_temp.get_name().c_str());
 578             state->spumux_file <<
 579                 "<subpictures>\n"
 580                 "  <stream>\n"
 581                 "    <spu force='yes' start='00:00:00.00'\n"
 582                 "        highlight='" << state->links_temp.get_name() << "'\n"
 583                 "        select='" << state->links_temp.get_name() << "'>\n";
 584         }
 585
 586         rectangle window_rect = {
 587             0, 0, frame_params_.width, frame_params_.height
 588         };
 589
 590         int menu_num = resource_map_[page_queue_.front()].second;
 591
 592         for (/* no initialisation */;
 593              state->links_it != state->links_end;
 594              ++state->links_it)
 595         {
 596             nsCOMPtr<nsIDOMNode> node(*state->links_it);
 597
 598             // Find the link URI.
 599             nsCOMPtr<nsILink> link(do_QueryInterface(node));
 600             assert(link);
 601             nsCOMPtr<nsIURI> uri;
 602             check(link->GetHrefURI(getter_AddRefs(uri)));
 603             std::string uri_string;
 604             {
 605                 nsCString uri_ns_string;
 606                 check(uri->GetSpec(uri_ns_string));
 607                 uri_string.assign(uri_ns_string.BeginReading(),
 608                                   uri_ns_string.EndReading());
 609             }
 610             std::string uri_sans_fragment(uri_string, 0, uri_string.find('#'));
 611
 612             // Is this a new link?
 613             if (!state->link_changing)
 614             {
 615                 // Find a rectangle enclosing the link and clip it to the
 616                 // window.
 617                 nsCOMPtr<nsIDOMElement> elem(do_QueryInterface(node));
 618                 assert(elem);
 619                 state->link_rect = get_elem_rect(ns_doc, elem);
 620                 state->link_rect &= window_rect;
 621
 622                 if (state->link_rect.empty())
 623                 {
 624                     std::cerr << "Ignoring invisible link to "
 625                               << uri_string << "\n";
 626                     continue;
 627                 }
 628
 629                 ++state->link_num;
 630
 631                 if (state->link_num >= dvd::menu_buttons_max)
 632                 {
 633                     if (state->link_num == dvd::menu_buttons_max)
 634                         std::cerr << "No more than " << dvd::menu_buttons_max
 635                                   << " buttons can be placed on a menu\n";
 636                     std::cerr << "Ignoring link to " << uri_string << "\n";
 637                     continue;
 638                 }
 639
 640                 state->spumux_file <<
 641                     "      <button x0='" << state->link_rect.left << "'"
 642                     " y0='" << state->link_rect.top << "'"
 643                     " x1='" << state->link_rect.right - 1 << "'"
 644                     " y1='" << state->link_rect.bottom - 1 << "'/>\n";
 645
 646                 // Check whether this is a link to a video or a page then
 647                 // add it to the known resources if not already seen; then
 648                 // add it to the menu entries.
 649                 nsCString path;
 650                 check(uri->GetPath(path));
 651                 dvd_contents::pgc_ref dest_pgc;
 652                 // FIXME: This is a bit of a hack.  Perhaps we could decide
 653                 // later based on the MIME type determined by Mozilla?
 654                 if ((path.Length() > 4
 655                      && std::strcmp(path.EndReading() - 4, ".vob") == 0)
 656                     || (path.Length() > 8
 657                         && std::strcmp(path.EndReading() - 8, ".voblist")
 658                            == 0))
 659                 {
 660                     PRBool is_file;
 661                     check(uri->SchemeIs("file", &is_file));
 662                     if (!is_file)
 663                     {
 664                         std::cerr << "Links to video must use the file:"
 665                                   << " scheme\n";
 666                         continue;
 667                     }
 668                     dest_pgc = add_title(uri_sans_fragment);
 669                 }
 670                 else
 671                 {
 672                     dest_pgc = add_menu(uri_sans_fragment);
 673                 }
 674                 contents_.menus[menu_num].entries.push_back(dest_pgc);
 675
 676                 nsCOMPtr<nsIContent> content(do_QueryInterface(node));
 677                 assert(content);
 678                 nsCOMPtr<nsIDOMEventTarget> event_target(
 679                     do_QueryInterface(node));
 680                 assert(event_target);
 681
 682                 state->norm_pixbuf = Gdk::Pixbuf::create(
 683                     Glib::RefPtr<Gdk::Drawable>(window),
 684                     window->get_colormap(),
 685                     state->link_rect.left,
 686                     state->link_rect.top,
 687                     0,
 688                     0,
 689                     state->link_rect.right - state->link_rect.left,
 690                     state->link_rect.bottom - state->link_rect.top);
 691
 692                 nsCOMPtr<nsIDOMEvent> event;
 693                 check(event_factory->CreateEvent(
 694                           NS_ConvertASCIItoUTF16("MouseEvents"),
 695                           getter_AddRefs(event)));
 696                 nsCOMPtr<nsIDOMMouseEvent> mouse_event(
 697                     do_QueryInterface(event));
 698                 assert(mouse_event);
 699                 check(mouse_event->InitMouseEvent(
 700                           NS_ConvertASCIItoUTF16("mouseover"),
 701                           true,  // can bubble
 702                           true,  // cancelable
 703                           view,
 704                           0,     // detail: mouse click count
 705                           state->link_rect.left, // screenX
 706                           state->link_rect.top,  // screenY
 707                           state->link_rect.left, // clientX
 708                           state->link_rect.top,  // clientY
 709                           false, false, false, false, // qualifiers
 710                           0,     // button: left (or primary)
 711                           0));   // related target
 712                 PRBool dummy;
 713                 check(event_target->DispatchEvent(mouse_event,
 714                                                   &dummy));
 715                 check(event_state_man->SetContentState(content,
 716                                                        NS_EVENT_STATE_HOVER));
 717
 718                 pres_shell->FlushPendingNotifications(true);
 719
 720                 // We may have to exit and wait for image loading
 721                 // to complete, at which point we will be called
 722                 // again.
 723                 if (browser_is_busy())
 724                 {
 725                     state->link_changing = true;
 726                     page_state_ = state;
 727                     return;
 728                 }
 729             }
 730
 731             window->process_updates(true);
 732
 733             Glib::RefPtr<Gdk::Pixbuf> changed_pixbuf(
 734                 Gdk::Pixbuf::create(
 735                     Glib::RefPtr<Gdk::Drawable>(window),
 736                     window->get_colormap(),
 737                     state->link_rect.left,
 738                     state->link_rect.top,
 739                     0,
 740                     0,
 741                     state->link_rect.right - state->link_rect.left,
 742                     state->link_rect.bottom - state->link_rect.top));
 743             diff_rgb_pixbufs(
 744                 state->norm_pixbuf,
 745                 changed_pixbuf,
 746                 state->diff_pixbuf,
 747                 state->link_rect.left,
 748                 state->link_rect.top,
 749                 state->link_rect.right - state->link_rect.left,
 750                 state->link_rect.bottom - state->link_rect.top);
 751         }
 752
 753         quantise_rgba_pixbuf(state->diff_pixbuf, dvd::button_n_colours);
 754
 755         std::cout << "saving " << state->links_temp.get_name()
 756                   << std::endl;
 757         state->diff_pixbuf->save(state->links_temp.get_name(), "png");
 758
 759         state->spumux_file <<
 760             "    </spu>\n"
 761             "  </stream>\n"
 762             "</subpictures>\n";
 763
 764         state->spumux_file.close();
 765
 766         // TODO: if (!state->spumux_file) throw ...
 767
 768         {
 769             std::ostringstream command_stream;
 770             command_stream << "pngtopnm "
 771                            << background_temp_->get_name()
 772                            << " | ppmtoy4m -v0 -n1 -F"
 773                            << frame_params_.rate_numer
 774                            << ":" << frame_params_.rate_denom
 775                            << " -A" << frame_params_.pixel_ratio_width
 776                            << ":" << frame_params_.pixel_ratio_height
 777                            << (" -Ip -S420_mpeg2"
 778                                " | mpeg2enc -v0 -f8 -a2 -o/dev/stdout"
 779                                " | mplex -v0 -f8 -o/dev/stdout /dev/stdin"
 780                                " | spumux -v0 -mdvd ")
 781                            << state->spumux_temp.get_name()
 782                            << " > "
 783                            << contents_.menus[menu_num].vob_temp->get_name();
 784             std::string command(command_stream.str());
 785             const char * argv[] = {
 786                 "/bin/sh", "-c", command.c_str(), 0
 787             };
 788             std::cout << "running " << argv[2] << std::endl;
 789             int command_result;
 790             Glib::spawn_sync(".",
 791                              Glib::ArrayHandle<std::string>(
 792                                  argv, sizeof(argv)/sizeof(argv[0]),
 793                                  Glib::OWNERSHIP_NONE),
 794                              Glib::SPAWN_STDOUT_TO_DEV_NULL,
 795                              SigC::Slot0<void>(),
 796                              0, 0,
 797                              &command_result);
 798             if (command_result != 0)
 799                 throw std::runtime_error("spumux pipeline failed");
 800         }
 801     }
 802
 803     void generate_dvd(const dvd_contents & contents,
 804                       const std::string & output_dir)
 805     {
 806         temp_file temp("webdvd-dvdauthor-");
 807         temp.close();
 808         std::ofstream file(temp.get_name().c_str());
 809
 810         // We generate code that uses registers in the following way:
 811         //
 812         // g0:     scratch
 813         // g1:     current location
 814         // g12:    location that last jumped to a video
 815         //
 816         // All locations are divided into two bitfields: the least
 817         // significant 10 bits are a page/menu number and the most
 818         // significant 6 bits are a link/button number, and numbering
 819         // starts at 1, not 0.  This is done for compatibility with
 820         // the encoding of the s8 (button) register.
 821         //
 822         static const int button_mult = dvd::reg_s8_button_mult;
 823         static const int menu_mask = button_mult - 1;
 824         static const int button_mask = (1 << dvd::reg_bits) - button_mult;
 825
 826         file <<
 827             "<dvdauthor>\n"
 828             "  <vmgm>\n"
 829             "    <menus>\n";
 830
 831         for (std::size_t menu_num = 0;
 832              menu_num != contents.menus.size();
 833              ++menu_num)
 834         {
 835             const dvd_contents::menu & menu = contents.menus[menu_num];
 836
 837             if (menu_num == 0)
 838             {
 839                 // This is the first (title) menu, displayed when the
 840                 // disc is first played.
 841                 file <<
 842                     "      <pgc entry='title'>\n"
 843                     "        <pre>\n"
 844                     // Initialise the current location if it is not set
 845                     // (all general registers are initially 0).
 846                     "          if (g1 eq 0)\n"
 847                     "            g1 = " << 1 + button_mult << ";\n";
 848             }
 849             else
 850             {
 851                 file <<
 852                     "      <pgc>\n"
 853                     "        <pre>\n";
 854             }
 855
 856             // When a title finishes or the user presses the menu
 857             // button, this always jumps to the titleset's root menu.
 858             // We want to return the user to the last menu they used.
 859             // So we arrange for each titleset's root menu to return
 860             // to the vmgm title menu and then dispatch from there to
 861             // whatever the correct menu is.  We determine the correct
 862             // menu by looking at the menu part of g1.
 863
 864             file << "          g0 = g1 &amp; " << menu_mask << ";\n";
 865
 866             // There is a limit of 128 VM instructions in each PGC.
 867             // Therefore in each menu's <pre> section we generate
 868             // jumps to menus with numbers greater by 512, 256, 128,
 869             // ..., 1 where (a) such a menu exists, (b) this menu
 870             // number is divisible by twice that increment and (c) the
 871             // correct menu is that or a later menu.  Thus each menu
 872             // has at most 10 such conditional jumps and is reachable
 873             // by at most 10 jumps from the title menu.  This chain of
 874             // jumps might take too long on some players; this has yet
 875             // to be investigated.
 876
 877             for (std::size_t menu_incr = (menu_mask + 1) / 2;
 878                  menu_incr != 0;
 879                  menu_incr /= 2)
 880             {
 881                 if (menu_num + menu_incr < contents.menus.size()
 882                     && (menu_num & (menu_incr * 2 - 1)) == 0)
 883                 {
 884                     file <<
 885                         "          if (g0 ge " << 1 + menu_num + menu_incr
 886                                                << ")\n"
 887                         "            jump menu " << 1 + menu_num + menu_incr
 888                                                << ";\n";
 889                 }
 890             }
 891
 892             file <<
 893                 // Highlight the appropriate button.
 894                 "          s8 = g1 &amp; " << button_mask << ";\n"
 895                 "        </pre>\n"
 896                 "        <vob file='" << menu.vob_temp->get_name() << "'/>\n";
 897
 898             for (std::size_t button_num = 0;
 899                  button_num != menu.entries.size();
 900                  ++button_num)
 901             {
 902                 file << "        <button> ";
 903
 904                 if (menu.entries[button_num].first == dvd_contents::menu_pgc)
 905                 {
 906                     int dest_menu_num = menu.entries[button_num].second;
 907
 908                     // Look for a button on the new menu that links
 909                     // back to this one.  If there is one, set that to
 910                     // be the highlighted button; otherwise, use the
 911                     // first button.
 912                     const std::vector<dvd_contents::pgc_ref> &
 913                         dest_menu_entries =
 914                         contents.menus[dest_menu_num].entries;
 915                     dvd_contents::pgc_ref this_pgc(
 916                         dvd_contents::menu_pgc, menu_num);
 917                     std::size_t dest_button_num = dest_menu_entries.size();
 918                     while (dest_button_num != 0
 919                            && dest_menu_entries[--dest_button_num] != this_pgc)
 920                         ;
 921
 922                     file << "g1 = "
 923                          << (1 + dest_menu_num
 924                              + (1 + dest_button_num) * button_mult)
 925                          << "; jump menu " << 1 + dest_menu_num << ";";
 926                 }
 927                 else
 928                 {
 929                     assert(menu.entries[button_num].first
 930                            == dvd_contents::title_pgc);
 931
 932                     file << "g1 = "
 933                          << 1 + menu_num + (1 + button_num) * button_mult
 934                          << "; jump title "
 935                          << 1 + menu.entries[button_num].second << ";";
 936                 }
 937
 938                 file <<  " </button>\n";
 939             }
 940
 941             file << "      </pgc>\n";
 942         }
 943
 944         file <<
 945             "    </menus>\n"
 946             "  </vmgm>\n";
 947
 948         // Generate a titleset for each title.  This appears to make
 949         // jumping to titles a whole lot simpler (but limits us to 99
 950         // titles).
 951         for (std::size_t title_num = 0;
 952              title_num != contents.titles.size();
 953              ++title_num)
 954         {
 955             file <<
 956                 "  <titleset>\n"
 957                 // Generate a dummy menu so that the menu button on the
 958                 // remote control will work.
 959                 "    <menus>\n"
 960                 "      <pgc entry='root'>\n"
 961                 "        <pre> jump vmgm menu; </pre>\n"
 962                 "      </pgc>\n"
 963                 "    </menus>\n"
 964                 "    <titles>\n"
 965                 "      <pgc>\n"
 966                 // Record calling location.
 967                 "        <pre> g12 = g1; </pre>\n"
 968                  << contents.titles[title_num].vob_list <<
 969                 // If the menu location has not been changed during
 970                 // the title, set the location to be the following
 971                 // button in the menu.  In any case, return to some
 972                 // menu.
 973                 "        <post> if (g1 eq g12) g1 = g1 + " << button_mult
 974                  << "; call menu; </post>\n"
 975                 "      </pgc>\n"
 976                 "    </titles>\n"
 977                 "  </titleset>\n";
 978         }
 979
 980         file <<
 981             "</dvdauthor>\n";
 982
 983         file.close();
 984
 985         {
 986             const char * argv[] = {
 987                 "dvdauthor",
 988                 "-o", output_dir.c_str(),
 989                 "-x", temp.get_name().c_str(),
 990                 0
 991             };
 992             int command_result;
 993             Glib::spawn_sync(".",
 994                              Glib::ArrayHandle<std::string>(
 995                                  argv, sizeof(argv)/sizeof(argv[0]),
 996                                  Glib::OWNERSHIP_NONE),
 997                              Glib::SPAWN_SEARCH_PATH
 998                              | Glib::SPAWN_STDOUT_TO_DEV_NULL,
 999                              SigC::Slot0<void>(),
1000                              0, 0,
1001                              &command_result);
1002             if (command_result != 0)
1003                 throw std::runtime_error("dvdauthor failed");
1004         }
1005     }
1006
1007     const video::frame_params & lookup_frame_params(const char * str)
1008     {
1009         assert(str);
1010         static const struct { const char * str; bool is_ntsc; }
1011         known_strings[] = {
1012             { "NTSC",  true },
1013             { "ntsc",  true },
1014             { "PAL",   false },
1015             { "pal",   false },
1016             // For DVD purposes, SECAM can be treated identically to PAL.
1017             { "SECAM", false },
1018             { "secam", false }
1019         };
1020         for (std::size_t i = 0;
1021              i != sizeof(known_strings)/sizeof(known_strings[0]);
1022              ++i)
1023             if (std::strcmp(str, known_strings[i].str) == 0)
1024                 return known_strings[i].is_ntsc ?
1025                     video::ntsc_params : video::pal_params;
1026         throw std::runtime_error(
1027             std::string("Invalid video standard: ").append(str));
1028     }
1029
1030     void print_usage(std::ostream & stream, const char * command_name)
1031     {
1032         stream << "Usage: " << command_name
1033                << (" [gtk-options] [--video-std std-name]"
1034                    " [--preview] menu-url [output-dir]\n");
1035     }
1036
1037     void set_browser_preferences()
1038     {
1039         nsCOMPtr<nsIPrefService> pref_service;
1040         static const nsCID pref_service_cid = NS_PREFSERVICE_CID;
1041         check(CallGetService<nsIPrefService>(pref_service_cid,
1042                                              getter_AddRefs(pref_service)));
1043         nsCOMPtr<nsIPrefBranch> pref_branch;
1044
1045         // Disable IE-compatibility kluge that causes backgrounds to
1046         // sometimes/usually be missing from snapshots.  This is only
1047         // effective from Mozilla 1.8 onward.
1048 #       if MOZ_VERSION_MAJOR > 1                                 \
1049            || (MOZ_VERSION_MAJOR == 1 && MOZ_VERSION_MINOR >= 8)
1050         check(pref_service->GetDefaultBranch("layout",
1051                                              getter_AddRefs(pref_branch)));
1052         check(pref_branch->SetBoolPref(
1053                   "fire_onload_after_image_background_loads",
1054                   true));
1055 #       endif
1056
1057         // Set display resolution.  With standard-definition video we
1058         // will be fitting ~600 pixels across a screen typically
1059         // ranging from 10 to 25 inches wide, for a resolution of
1060         // 24-60 dpi.  I therefore declare the average horizontal
1061         // resolution to be 40 dpi.  The vertical resolution will be
1062         // slightly higher (PAL/SECAM) or lower (NTSC), but
1063         // unfortunately Mozilla doesn't support non-square pixels
1064         // (and neither do fontconfig or Xft anyway).
1065         check(pref_service->GetDefaultBranch("browser.display",
1066                                              getter_AddRefs(pref_branch)));
1067         check(pref_branch->SetIntPref("screen_resolution", 40));
1068     }
1069
1070 } // namespace
1071
1072 int main(int argc, char ** argv)
1073 {
1074     try
1075     {
1076         video::frame_params frame_params = video::pal_params;
1077         bool preview_mode = false;
1078         std::string menu_url;
1079         std::string output_dir;
1080
1081         // Do initial option parsing.  We have to do this before
1082         // letting Gtk parse the arguments since we may need to spawn
1083         // Xvfb first.
1084         int argi = 1;
1085         while (argi != argc)
1086         {
1087             if (std::strcmp(argv[argi], "--") == 0)
1088             {
1089                 break;
1090             }
1091             else if (std::strcmp(argv[argi], "--help") == 0)
1092             {
1093                 print_usage(std::cout, argv[0]);
1094                 return EXIT_SUCCESS;
1095             }
1096             else if (std::strcmp(argv[argi], "--preview") == 0)
1097             {
1098                 preview_mode = true;
1099                 argi += 1;
1100             }
1101             else if (std::strcmp(argv[argi], "--video-std") == 0)
1102             {
1103                 if (argi + 1 == argc)
1104                 {
1105                     std::cerr << "Missing argument to --video-std\n";
1106                     print_usage(std::cerr, argv[0]);
1107                     return EXIT_FAILURE;
1108                 }
1109                 frame_params = lookup_frame_params(argv[argi + 1]);
1110                 argi += 2;
1111             }
1112             else
1113             {
1114                 argi += 1;
1115             }
1116         }
1117
1118         std::auto_ptr<x_frame_buffer> fb;
1119         if (!preview_mode)
1120         {
1121             // Spawn Xvfb and set env variables so that Xlib will use it
1122             // Use 8 bits each for RGB components, which should translate into
1123             // "enough" bits for YUV components.
1124             fb.reset(new x_frame_buffer(frame_params.width,
1125                                         frame_params.height,
1126                                         3 * 8));
1127             setenv("XAUTHORITY", fb->get_authority().c_str(), true);
1128             setenv("DISPLAY", fb->get_display().c_str(), true);
1129         }
1130
1131         // Initialise Gtk
1132         Gtk::Main kit(argc, argv);
1133
1134         // Complete option parsing with Gtk's options out of the way.
1135         argi = 1;
1136         while (argi != argc)
1137         {
1138             if (std::strcmp(argv[argi], "--") == 0)
1139             {
1140                 argi += 1;
1141                 break;
1142             }
1143             else if (std::strcmp(argv[argi], "--preview") == 0)
1144             {
1145                 argi += 1;
1146             }
1147             else if (std::strcmp(argv[argi], "--video-std") == 0)
1148             {
1149                 argi += 2;
1150             }
1151             else if (argv[argi][0] == '-')
1152             {
1153                 std::cerr << "Invalid option: " << argv[argi] << "\n";
1154                 print_usage(std::cerr, argv[0]);
1155                 return EXIT_FAILURE;
1156             }
1157             else
1158             {
1159                 break;
1160             }
1161         }
1162
1163         // Look for a starting URL or filename and (except in preview
1164         // mode) an output directory after the options.
1165         if (argc - argi != (preview_mode ? 1 : 2))
1166         {
1167             print_usage(std::cerr, argv[0]);
1168             return EXIT_FAILURE;
1169         }
1170         if (std::strstr(argv[argi], "://"))
1171         {
1172             // It appears to be an absolute URL, so use it as-is.
1173             menu_url = argv[argi];
1174         }
1175         else
1176         {
1177             // Assume it's a filename.  Resolve it to an absolute URL.
1178             std::string path(argv[argi]);
1179             if (!Glib::path_is_absolute(path))
1180                 path = Glib::build_filename(Glib::get_current_dir(), path);
1181             menu_url = Glib::filename_to_uri(path);
1182         }
1183         if (!preview_mode)
1184             output_dir = argv[argi + 1];
1185
1186         // Initialise Mozilla
1187         browser_widget::initialiser browser_init;
1188         set_browser_preferences();
1189
1190         // Run the browser/converter
1191         webdvd_window window(frame_params, menu_url, output_dir);
1192         Gtk::Main::run(window);
1193     }
1194     catch (std::exception & e)
1195     {
1196         std::cerr << "Fatal error: " << e.what() << "\n";
1197         return EXIT_FAILURE;
1198     }
1199
1200     return EXIT_SUCCESS;
1201 }