diff options
Diffstat (limited to 'backend/djvu/djvu-links.c')
| -rw-r--r-- | backend/djvu/djvu-links.c | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/backend/djvu/djvu-links.c b/backend/djvu/djvu-links.c new file mode 100644 index 00000000..d13af0be --- /dev/null +++ b/backend/djvu/djvu-links.c @@ -0,0 +1,434 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; c-indent-level: 8 -*- */ +/* + * Implements hyperlink functionality for Djvu files. + * Copyright (C) 2006 Pauli Virtanen <[email protected]> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include <config.h> +#include <string.h> +#include <glib.h> +#include <libdjvu/miniexp.h> +#include "djvu-document.h" +#include "djvu-links.h" +#include "djvu-document-private.h" +#include "ev-document-links.h" +#include "ev-mapping-list.h" + +static gboolean number_from_miniexp(miniexp_t sexp, int *number) +{ + if (miniexp_numberp (sexp)) { + *number = miniexp_to_int (sexp); + return TRUE; + } else { + return FALSE; + } +} + +static gboolean string_from_miniexp(miniexp_t sexp, const char **str) +{ + if (miniexp_stringp (sexp)) { + *str = miniexp_to_str (sexp); + return TRUE; + } else { + return FALSE; + } +} + +static gboolean number_from_string_10(const gchar *str, guint64 *number) +{ + gchar *end_ptr; + + *number = g_ascii_strtoull(str, &end_ptr, 10); + if (*end_ptr == '\0') { + return TRUE; + } else { + return FALSE; + } +} + +static EvLinkDest * +get_djvu_link_dest (const DjvuDocument *djvu_document, const gchar *link_name, int base_page) +{ + guint64 page_num = 0; + + /* #pagenum, #+pageoffset, #-pageoffset */ + if (g_str_has_prefix (link_name, "#")) { + if (base_page > 0 && g_str_has_prefix (link_name+1, "+")) { + if (number_from_string_10 (link_name + 2, &page_num)) { + return ev_link_dest_new_page (base_page + page_num); + } + } else if (base_page > 0 && g_str_has_prefix (link_name+1, "-")) { + if (number_from_string_10 (link_name + 2, &page_num)) { + return ev_link_dest_new_page (base_page - page_num); + } + } else { + if (number_from_string_10 (link_name + 1, &page_num)) { + return ev_link_dest_new_page (page_num - 1); + } + } + } else { + /* FIXME: component file identifiers */ + } + + return NULL; +} + +static EvLinkAction * +get_djvu_link_action (const DjvuDocument *djvu_document, const gchar *link_name, int base_page) +{ + EvLinkDest *ev_dest = NULL; + EvLinkAction *ev_action = NULL; + + ev_dest = get_djvu_link_dest (djvu_document, link_name, base_page); + + if (ev_dest) { + ev_action = ev_link_action_new_dest (ev_dest); + } else if (strstr(link_name, "://") != NULL) { + /* It's probably an URI */ + ev_action = ev_link_action_new_external_uri (link_name); + } else { + /* FIXME: component file identifiers */ + } + + return ev_action; +} + +static gchar * +str_to_utf8 (const gchar *text) +{ + static const gchar *encodings_to_try[2]; + static gint n_encodings_to_try = 0; + gchar *utf8_text = NULL; + gint i; + + if (n_encodings_to_try == 0) { + const gchar *charset; + gboolean charset_is_utf8; + + charset_is_utf8 = g_get_charset (&charset); + if (!charset_is_utf8) { + encodings_to_try[n_encodings_to_try++] = charset; + } + + if (g_ascii_strcasecmp (charset, "ISO-8859-1") != 0) { + encodings_to_try[n_encodings_to_try++] = "ISO-8859-1"; + } + } + + for (i = 0; i < n_encodings_to_try; i++) { + utf8_text = g_convert (text, -1, "UTF-8", + encodings_to_try[i], + NULL, NULL, NULL); + if (utf8_text) + break; + } + + return utf8_text; +} + +/** + * Builds the index GtkTreeModel from DjVu s-expr + * + * (bookmarks + * ("title1" "dest1" + * ("title12" "dest12" + * ... ) + * ... ) + * ("title2" "dest2" + * ... ) + * ... ) + */ +static void +build_tree (const DjvuDocument *djvu_document, + GtkTreeModel *model, + GtkTreeIter *parent, + miniexp_t iter) +{ + const char *title, *link_dest; + char *title_markup; + + EvLinkAction *ev_action = NULL; + EvLink *ev_link = NULL; + GtkTreeIter tree_iter; + + if (miniexp_car (iter) == miniexp_symbol ("bookmarks")) { + /* The (bookmarks) cons */ + iter = miniexp_cdr (iter); + } else if ( miniexp_length (iter) >= 2 ) { + gchar *utf8_title = NULL; + + /* An entry */ + if (!string_from_miniexp (miniexp_car (iter), &title)) goto unknown_entry; + if (!string_from_miniexp (miniexp_cadr (iter), &link_dest)) goto unknown_entry; + + + if (!g_utf8_validate (title, -1, NULL)) { + utf8_title = str_to_utf8 (title); + title_markup = g_markup_escape_text (utf8_title, -1); + } else { + title_markup = g_markup_escape_text (title, -1); + } + + ev_action = get_djvu_link_action (djvu_document, link_dest, -1); + + if (g_str_has_suffix (link_dest, ".djvu")) { + /* FIXME: component file identifiers */ + } else if (ev_action) { + ev_link = ev_link_new (utf8_title ? utf8_title : title, ev_action); + gtk_tree_store_append (GTK_TREE_STORE (model), &tree_iter, parent); + gtk_tree_store_set (GTK_TREE_STORE (model), &tree_iter, + EV_DOCUMENT_LINKS_COLUMN_MARKUP, title_markup, + EV_DOCUMENT_LINKS_COLUMN_LINK, ev_link, + EV_DOCUMENT_LINKS_COLUMN_EXPAND, FALSE, + -1); + g_object_unref (ev_link); + } else { + gtk_tree_store_append (GTK_TREE_STORE (model), &tree_iter, parent); + gtk_tree_store_set (GTK_TREE_STORE (model), &tree_iter, + EV_DOCUMENT_LINKS_COLUMN_MARKUP, title_markup, + EV_DOCUMENT_LINKS_COLUMN_EXPAND, FALSE, + -1); + } + + g_free (title_markup); + g_free (utf8_title); + iter = miniexp_cddr (iter); + parent = &tree_iter; + } else { + goto unknown_entry; + } + + for (; iter != miniexp_nil; iter = miniexp_cdr (iter)) { + build_tree (djvu_document, model, parent, miniexp_car (iter)); + } + return; + + unknown_entry: + g_warning ("DjvuLibre error: Unknown entry in bookmarks"); + return; +} + +static gboolean +get_djvu_hyperlink_area (ddjvu_pageinfo_t *page_info, + miniexp_t sexp, + EvMapping *ev_link_mapping) +{ + miniexp_t iter; + + iter = sexp; + + if ((miniexp_car (iter) == miniexp_symbol ("rect") || miniexp_car (iter) == miniexp_symbol ("oval")) + && miniexp_length (iter) == 5) { + /* FIXME: get bounding box for (oval) since Evince doesn't support shaped links */ + int minx, miny, width, height; + + iter = miniexp_cdr (iter); + if (!number_from_miniexp (miniexp_car (iter), &minx)) goto unknown_link; + iter = miniexp_cdr (iter); + if (!number_from_miniexp (miniexp_car (iter), &miny)) goto unknown_link; + iter = miniexp_cdr (iter); + if (!number_from_miniexp (miniexp_car (iter), &width)) goto unknown_link; + iter = miniexp_cdr (iter); + if (!number_from_miniexp (miniexp_car (iter), &height)) goto unknown_link; + + ev_link_mapping->area.x1 = minx; + ev_link_mapping->area.x2 = (minx + width); + ev_link_mapping->area.y1 = (page_info->height - (miny + height)); + ev_link_mapping->area.y2 = (page_info->height - miny); + } else if (miniexp_car (iter) == miniexp_symbol ("poly") + && miniexp_length (iter) >= 5 && miniexp_length (iter) % 2 == 1) { + + /* FIXME: get bounding box since Evince doesn't support shaped links */ + int minx = G_MAXINT, miny = G_MAXINT; + int maxx = G_MININT, maxy = G_MININT; + + iter = miniexp_cdr(iter); + while (iter != miniexp_nil) { + int x, y; + + if (!number_from_miniexp (miniexp_car(iter), &x)) goto unknown_link; + iter = miniexp_cdr (iter); + if (!number_from_miniexp (miniexp_car(iter), &y)) goto unknown_link; + iter = miniexp_cdr (iter); + + minx = MIN (minx, x); + miny = MIN (miny, y); + maxx = MAX (maxx, x); + maxy = MAX (maxy, y); + } + + ev_link_mapping->area.x1 = minx; + ev_link_mapping->area.x2 = maxx; + ev_link_mapping->area.y1 = (page_info->height - maxy); + ev_link_mapping->area.y2 = (page_info->height - miny); + } else { + /* unknown */ + goto unknown_link; + } + + return TRUE; + + unknown_link: + g_warning("DjvuLibre error: Unknown hyperlink area %s", miniexp_to_name(miniexp_car(sexp))); + return FALSE; +} + +static EvMapping * +get_djvu_hyperlink_mapping (DjvuDocument *djvu_document, + int page, + ddjvu_pageinfo_t *page_info, + miniexp_t sexp) +{ + EvMapping *ev_link_mapping = NULL; + EvLinkAction *ev_action = NULL; + miniexp_t iter; + const char *url, *url_target, *comment; + + ev_link_mapping = g_new (EvMapping, 1); + + iter = sexp; + + if (miniexp_car (iter) != miniexp_symbol ("maparea")) goto unknown_mapping; + + iter = miniexp_cdr(iter); + + if (miniexp_caar(iter) == miniexp_symbol("url")) { + if (!string_from_miniexp (miniexp_cadr (miniexp_car (iter)), &url)) goto unknown_mapping; + if (!string_from_miniexp (miniexp_caddr (miniexp_car (iter)), &url_target)) goto unknown_mapping; + } else { + if (!string_from_miniexp (miniexp_car(iter), &url)) goto unknown_mapping; + url_target = NULL; + } + + iter = miniexp_cdr (iter); + if (!string_from_miniexp (miniexp_car(iter), &comment)) goto unknown_mapping; + + iter = miniexp_cdr (iter); + if (!get_djvu_hyperlink_area (page_info, miniexp_car(iter), ev_link_mapping)) goto unknown_mapping; + + iter = miniexp_cdr (iter); + /* FIXME: DjVu hyperlink attributes are ignored */ + + ev_action = get_djvu_link_action (djvu_document, url, page); + if (!ev_action) goto unknown_mapping; + + ev_link_mapping->data = ev_link_new (comment, ev_action); + + return ev_link_mapping; + + unknown_mapping: + if (ev_link_mapping) g_free(ev_link_mapping); + g_warning("DjvuLibre error: Unknown hyperlink %s", miniexp_to_name(miniexp_car(sexp))); + return NULL; +} + + +gboolean +djvu_links_has_document_links (EvDocumentLinks *document_links) +{ + DjvuDocument *djvu_document = DJVU_DOCUMENT (document_links); + miniexp_t outline; + + while ((outline = ddjvu_document_get_outline (djvu_document->d_document)) == miniexp_dummy) + djvu_handle_events (djvu_document, TRUE, NULL); + + if (outline) { + ddjvu_miniexp_release (djvu_document->d_document, outline); + return TRUE; + } + + return FALSE; +} + +EvMappingList * +djvu_links_get_links (EvDocumentLinks *document_links, + gint page, + double scale_factor) +{ + DjvuDocument *djvu_document = DJVU_DOCUMENT (document_links); + GList *retval = NULL; + miniexp_t page_annotations = miniexp_nil; + miniexp_t *hyperlinks = NULL, *iter = NULL; + EvMapping *ev_link_mapping; + ddjvu_pageinfo_t page_info; + + while ((page_annotations = ddjvu_document_get_pageanno (djvu_document->d_document, page)) == miniexp_dummy) + djvu_handle_events (djvu_document, TRUE, NULL); + + while (ddjvu_document_get_pageinfo (djvu_document->d_document, page, &page_info) < DDJVU_JOB_OK) + djvu_handle_events(djvu_document, TRUE, NULL); + + if (page_annotations) { + hyperlinks = ddjvu_anno_get_hyperlinks (page_annotations); + if (hyperlinks) { + for (iter = hyperlinks; *iter; ++iter) { + ev_link_mapping = get_djvu_hyperlink_mapping (djvu_document, page, &page_info, *iter); + if (ev_link_mapping) { + ev_link_mapping->area.x1 *= scale_factor; + ev_link_mapping->area.x2 *= scale_factor; + ev_link_mapping->area.y1 *= scale_factor; + ev_link_mapping->area.y2 *= scale_factor; + retval = g_list_prepend (retval, ev_link_mapping); + } + } + free (hyperlinks); + } + ddjvu_miniexp_release (djvu_document->d_document, page_annotations); + } + + return ev_mapping_list_new (page, retval, (GDestroyNotify)g_object_unref); +} + +EvLinkDest * +djvu_links_find_link_dest (EvDocumentLinks *document_links, + const gchar *link_name) +{ + DjvuDocument *djvu_document = DJVU_DOCUMENT (document_links); + EvLinkDest *ev_dest = NULL; + + ev_dest = get_djvu_link_dest (djvu_document, link_name, -1); + + if (!ev_dest) { + g_warning ("DjvuLibre error: unknown link destination %s", link_name); + } + + return ev_dest; +} + +GtkTreeModel * +djvu_links_get_links_model (EvDocumentLinks *document_links) +{ + DjvuDocument *djvu_document = DJVU_DOCUMENT (document_links); + GtkTreeModel *model = NULL; + miniexp_t outline = miniexp_nil; + + while ((outline = ddjvu_document_get_outline (djvu_document->d_document)) == miniexp_dummy) + djvu_handle_events (djvu_document, TRUE, NULL); + + if (outline) { + model = (GtkTreeModel *) gtk_tree_store_new (EV_DOCUMENT_LINKS_COLUMN_NUM_COLUMNS, + G_TYPE_STRING, + G_TYPE_OBJECT, + G_TYPE_BOOLEAN, + G_TYPE_STRING); + build_tree (djvu_document, model, NULL, outline); + + ddjvu_miniexp_release (djvu_document->d_document, outline); + } + + return model; +} |