PDFViewer/src/pdfviewer.c

/* $Id$ */
static char const _copyright[] =
"Copyright © 2010-2011 Sébastien Bocahu <zecrazytux@zecrazytux.net>\n"
"Copyright © 2011-2014 Pierre Pronchery <khorben@defora.org>";
static char const _license[] =
"This program is free software; you can redistribute it and/or modify\n"
"it under the terms of the GNU General Public License as published by the\n"
"Free Software Foundation, version 3 of the License.\n"
"\n"
"This program is distributed in the hope that it will be useful,\n"
"but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
"MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
"GNU General Public License for more details.\n"
"\n"
"You should have received a copy of the GNU General Public License\n"
"along with this program. If not, see <http://www.gnu.org/licenses/>.\n";



#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <math.h>
#include <libintl.h>
#include <gdk/gdkkeysyms.h>
#include <poppler.h>
#include <Desktop.h>
#include "callbacks.h"
#include "pdfviewer.h"
#include "../config.h"
#define _(string) gettext(string)
#define N_(string) (string)

/* constants */
#ifndef PROGNAME
# define PROGNAME	"pdfviewer"
#endif


/* PDFviewer */
/* private */
/* types */
typedef struct _PDF
{
	PopplerDocument * document;

	int pages;
	int current;

	GtkWidget * area;
	cairo_surface_t * surface;
	double scale;
} PDF;

struct _PDFviewer
{
	PDF * pdf;

	/* widgets */
	PangoFontDescription * bold;
	GtkWidget * window;
#ifndef EMBEDDED
	GtkWidget * menubar;
#endif
	GtkWidget * view;
	GtkWidget * statusbar;
	GtkWidget * toolbar;
	GtkToolItem * tb_fullscreen;
	/* about */
	GtkWidget * ab_window;
};


/* variables */
static char const * _authors[] =
{
	"Sébastien Bocahu <zecrazytux@zecrazytux.net>",
	"Pierre Pronchery <khorben@defora.org>",
	NULL
};

static DesktopAccel _pdfviewer_accel[] =
{
#ifdef EMBEDDED
	{ G_CALLBACK(on_contents), 0, GDK_KEY_F1 },
#endif
	{ G_CALLBACK(on_fullscreen), 0, GDK_KEY_F11 },
	{ G_CALLBACK(on_next), 0, GDK_KEY_Page_Down },
	{ G_CALLBACK(on_next), GDK_CONTROL_MASK, GDK_KEY_N },
#ifdef EMBEDDED
	{ G_CALLBACK(on_open), GDK_CONTROL_MASK, GDK_KEY_O },
	{ G_CALLBACK(on_pdf_close), GDK_CONTROL_MASK, GDK_KEY_W },
#endif
	{ G_CALLBACK(on_previous), 0, GDK_KEY_Page_Up },
	{ G_CALLBACK(on_previous), GDK_CONTROL_MASK, GDK_KEY_P },
	{ NULL, 0, 0 }
};

#ifndef EMBEDDED
static DesktopMenu _pdfviewer_menu_file[] =
{
	{ N_("_Open"), G_CALLBACK(on_file_open), GTK_STOCK_OPEN,
		GDK_CONTROL_MASK, GDK_KEY_O },
	{ "", NULL, NULL, 0, 0 },
	{ N_("_Properties"), G_CALLBACK(on_file_properties),
		GTK_STOCK_PROPERTIES, GDK_MOD1_MASK, GDK_KEY_Return },
	{ "", NULL, NULL, 0, 0 },
	{ N_("_Close"), G_CALLBACK(on_file_close), GTK_STOCK_CLOSE,
		GDK_CONTROL_MASK, GDK_KEY_W },
	{ NULL, NULL, NULL, 0, 0 }
};

static DesktopMenu _pdfviewer_menu_edit[] =
{
	{ N_("_Preferences"), G_CALLBACK(on_edit_preferences),
		GTK_STOCK_PREFERENCES, GDK_CONTROL_MASK, GDK_KEY_P },
	{ NULL, NULL, NULL, 0, 0 }
};

static DesktopMenu _pdfviewer_menu_view[] =
{
	{ N_("Zoom _in"), G_CALLBACK(on_view_zoom_in), "zoom-in",
		GDK_CONTROL_MASK, GDK_KEY_plus },
	{ N_("Zoom _out"), G_CALLBACK(on_view_zoom_out), "zoom-out",
		GDK_CONTROL_MASK, GDK_KEY_minus },
	{ N_("Normal size"), G_CALLBACK(on_view_normal_size), "zoom-original",
		GDK_CONTROL_MASK, GDK_KEY_0 },
	{ "", NULL, NULL, 0, 0 },
#if GTK_CHECK_VERSION(2, 8, 0)
	{ N_("_Fullscreen"), G_CALLBACK(on_view_fullscreen),
		GTK_STOCK_FULLSCREEN, 0, GDK_KEY_F11 },
#else
	{ N_("_Fullscreen"), G_CALLBACK(on_view_fullscreen), NULL, 0,
		GDK_KEY_F11 },
#endif
	{ NULL, NULL, NULL, 0, 0 }
};

static DesktopMenu _pdfviewer_menu_help[] =
{
	{ N_("_Contents"), G_CALLBACK(on_help_contents), "help-contents", 0,
		GDK_KEY_F1 },
	{ N_("_About"), G_CALLBACK(on_help_about),
#if GTK_CHECK_VERSION(2, 6, 0)
		GTK_STOCK_ABOUT, 0, 0 },
#else
		NULL, 0, 0 },
#endif
	{ NULL, NULL, NULL, 0, 0 }
};

static DesktopMenubar _pdfviewer_menubar[] =
{
	{ N_("_File"), _pdfviewer_menu_file },
	{ N_("_Edit"), _pdfviewer_menu_edit },
	{ N_("_View"), _pdfviewer_menu_view },
	{ N_("_Help"), _pdfviewer_menu_help },
	{ NULL, NULL }
};
#endif

static DesktopToolbar _pdfviewer_toolbar[] =
{
	{ N_("Open"), G_CALLBACK(on_open), GTK_STOCK_OPEN, 0, 0, NULL },
	{ "", NULL, NULL, 0, 0, NULL },
	{ N_("Far before"), G_CALLBACK(on_far_before), GTK_STOCK_MEDIA_PREVIOUS,
		 0, 0, NULL },
	{ N_("Previous"), G_CALLBACK(on_previous), GTK_STOCK_GO_BACK,
		 0, 0, NULL },
	{ N_("Next"), G_CALLBACK(on_next), GTK_STOCK_GO_FORWARD, 0, 0, NULL },
	{ N_("Far after"), G_CALLBACK(on_far_after), GTK_STOCK_MEDIA_NEXT, 0, 0,
		NULL },
	{ "", NULL, NULL, 0, 0, NULL },
	{ N_("Zoom in"), G_CALLBACK(on_zoom_in), GTK_STOCK_ZOOM_IN, 0, 0,
		NULL },
	{ N_("Zoom out"), G_CALLBACK(on_zoom_out), GTK_STOCK_ZOOM_OUT, 0, 0,
		NULL },
	{ NULL, NULL, NULL, 0, 0, NULL }
};


/* prototypes */
static void _pdfviewer_set_title(PDFviewer * pdfviewer);


/* public */
/* functions */
/* pdfviewer_new */
PDFviewer * pdfviewer_new(void)
{
	PDFviewer * pdfviewer;
	GtkAccelGroup * group;
	GtkSettings * settings;
	GtkWidget * vbox;
	GtkWidget * widget;
	GtkToolItem * toolitem;

	if((pdfviewer = malloc(sizeof(*pdfviewer))) == NULL)
		return NULL;
	settings = gtk_settings_get_default();
	pdfviewer->pdf = NULL;
	/* widgets */
	pdfviewer->bold = pango_font_description_new();
	pango_font_description_set_weight(pdfviewer->bold, PANGO_WEIGHT_BOLD);
	group = gtk_accel_group_new();
	pdfviewer->window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
	gtk_window_add_accel_group(GTK_WINDOW(pdfviewer->window), group);
	g_object_unref(group);
	gtk_window_set_default_size(GTK_WINDOW(pdfviewer->window), 600, 400);
	_pdfviewer_set_title(pdfviewer);
#if GTK_CHECK_VERSION(2, 6, 0)
	gtk_window_set_icon_name(GTK_WINDOW(pdfviewer->window),
		"gnome-mime-application-pdf");
#endif
	g_signal_connect_swapped(G_OBJECT(pdfviewer->window), "delete-event",
			G_CALLBACK(on_closex), pdfviewer);
	vbox = gtk_vbox_new(FALSE, 0);
	/* menubar */
#ifndef EMBEDDED
	pdfviewer->menubar = desktop_menubar_create(_pdfviewer_menubar,
			pdfviewer, group);
	gtk_box_pack_start(GTK_BOX(vbox), pdfviewer->menubar, FALSE, FALSE, 0);
#endif
	desktop_accel_create(_pdfviewer_accel, pdfviewer, group);
	/* toolbar */
	pdfviewer->toolbar = desktop_toolbar_create(_pdfviewer_toolbar,
		pdfviewer, group);
	set_prevnext_sensitivity(pdfviewer);
#if GTK_CHECK_VERSION(2, 8, 0)
	toolitem = gtk_toggle_tool_button_new_from_stock(GTK_STOCK_FULLSCREEN);
#else
	toolitem = gtk_toggle_tool_button_new_from_stock(GTK_STOCK_ZOOM_FIT);
#endif
	pdfviewer->tb_fullscreen = toolitem;
	g_signal_connect_swapped(G_OBJECT(toolitem), "toggled", G_CALLBACK(
				on_fullscreen), pdfviewer);
	gtk_toolbar_insert(GTK_TOOLBAR(pdfviewer->toolbar), toolitem, -1);
	gtk_box_pack_start(GTK_BOX(vbox), pdfviewer->toolbar, FALSE, FALSE, 0);
	/* view */
	widget = gtk_scrolled_window_new(NULL, NULL);
	gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(widget),
			GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
	
	pdfviewer->view = gtk_drawing_area_new();
	gtk_scrolled_window_add_with_viewport(GTK_SCROLLED_WINDOW(widget),
			pdfviewer->view);
	gtk_box_pack_start(GTK_BOX(vbox), widget, TRUE, TRUE, 0);

	/* statusbar */
	pdfviewer->statusbar = gtk_statusbar_new();
	gtk_box_pack_start(GTK_BOX(vbox), pdfviewer->statusbar,
		FALSE, FALSE, 0);

	/* about */
	pdfviewer->ab_window = NULL;
	gtk_container_add(GTK_CONTAINER(pdfviewer->window), vbox);
	gtk_widget_show_all(pdfviewer->window);
	return pdfviewer;
}


/* pdfviewer_delete */
void pdfviewer_delete(PDFviewer * pdfviewer)
{
#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
#if 0 /* FIXME */
	if(pdfviewer->pdf != NULL)
		pdf_delete(pdfviewer->pdf);
#endif
	pdf_close(pdfviewer);
	pango_font_description_free(pdfviewer->bold);
	if(pdfviewer->window != NULL)
		gtk_widget_destroy(pdfviewer->window);
	free(pdfviewer);
}


/* accessors */
/* pdfviewer_set_fullscreen */
void pdfviewer_set_fullscreen(PDFviewer * pdfviewer, gboolean fullscreen)
{
	if(fullscreen == TRUE)
	{
#ifndef EMBEDDED
		gtk_widget_hide(pdfviewer->menubar);
#endif
		gtk_toggle_tool_button_set_active(GTK_TOGGLE_TOOL_BUTTON(
					pdfviewer->tb_fullscreen), TRUE);
		gtk_window_fullscreen(GTK_WINDOW(pdfviewer->window));
	}
	else
	{
#ifndef EMBEDDED
		gtk_widget_show(pdfviewer->menubar);
#endif
		gtk_toggle_tool_button_set_active(GTK_TOGGLE_TOOL_BUTTON(
					pdfviewer->tb_fullscreen), FALSE);
		gtk_window_unfullscreen(GTK_WINDOW(pdfviewer->window));
	}
}


/* useful */
/* pdfviewer_about */
static gboolean _about_on_closex(GtkWidget * widget);

void pdfviewer_about(PDFviewer * pdfviewer)
{
	if(pdfviewer->ab_window != NULL)
	{
		gtk_widget_show(pdfviewer->ab_window);
		return;
	}
	pdfviewer->ab_window = desktop_about_dialog_new();
	gtk_window_set_transient_for(GTK_WINDOW(pdfviewer->ab_window),
			GTK_WINDOW(pdfviewer->window));
	g_signal_connect(G_OBJECT(pdfviewer->ab_window), "delete-event",
			G_CALLBACK(_about_on_closex), NULL);
	desktop_about_dialog_set_authors(pdfviewer->ab_window, _authors);
	desktop_about_dialog_set_comments(pdfviewer->ab_window,
			_("PDF viewer for the DeforaOS desktop"));
	desktop_about_dialog_set_copyright(pdfviewer->ab_window, _copyright);
	desktop_about_dialog_set_license(pdfviewer->ab_window, _license);
	desktop_about_dialog_set_logo_icon_name(pdfviewer->ab_window,
			"document-print-preview");
	desktop_about_dialog_set_name(pdfviewer->ab_window, PACKAGE);
	desktop_about_dialog_set_version(pdfviewer->ab_window, VERSION);
	desktop_about_dialog_set_website(pdfviewer->ab_window,
			"http://www.defora.org/");
	gtk_widget_show(pdfviewer->ab_window);
}

static gboolean _about_on_closex(GtkWidget * widget)
{
	gtk_widget_hide(widget);
	return TRUE;
}


/* pdfviewer_error */
int pdfviewer_error(PDFviewer * pdfviewer, char const * message, int ret)
{
	GtkWidget * dialog;

	dialog = gtk_message_dialog_new(GTK_WINDOW(pdfviewer->window),
			GTK_DIALOG_DESTROY_WITH_PARENT,
			GTK_MESSAGE_ERROR, GTK_BUTTONS_CLOSE,
#if GTK_CHECK_VERSION(2, 6, 0)
			"%s", _("Error"));
	gtk_message_dialog_format_secondary_text(GTK_MESSAGE_DIALOG(dialog),
#endif
			"%s", message);
	gtk_window_set_title(GTK_WINDOW(dialog), _("Error"));
	g_signal_connect(G_OBJECT(dialog), "response", G_CALLBACK(
				gtk_widget_destroy), NULL);
	gtk_widget_show(dialog);
	return ret;
}


/* pdfviewer_close */
void pdfviewer_close(PDFviewer * pdfviewer)
{
#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
	gtk_widget_hide(pdfviewer->window);
	gtk_main_quit();
}


/* pdfviewer_fullscreen_toggle */
void pdfviewer_fullscreen_toggle(PDFviewer * pdfviewer)
{
	GdkWindow * window;

#if GTK_CHECK_VERSION(2, 14, 0)
	window = gtk_widget_get_window(pdfviewer->window);
#else
	window = pdfviewer->window->window;
#endif
	if((gdk_window_get_state(window) & GDK_WINDOW_STATE_FULLSCREEN)
			!= GDK_WINDOW_STATE_FULLSCREEN)
		pdfviewer_set_fullscreen(pdfviewer, TRUE);
	else
		pdfviewer_set_fullscreen(pdfviewer, FALSE);
}


/* pdfviewer_open */
int pdfviewer_open(PDFviewer * pdfviewer, char const * filename)
{
	int ret;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
	/* FIXME handle errors */
	if(filename == NULL)
		return pdfviewer_open_dialog(pdfviewer);
	if((ret = pdf_open(pdfviewer, filename)) != 0)
		return ret;
	_pdfviewer_set_title(pdfviewer);
	return 0;
}


/* pdfviewer_properties */
static GtkWidget * _properties_label(PDFviewer * pdfviewer,
		GtkSizeGroup * group, char const * label, char const * value);
static GtkWidget * _properties_label_date(PDFviewer * pdfviewer,
		GtkSizeGroup * group, char const * label, time_t t);

void pdfviewer_properties(PDFviewer * pdfviewer)
{
	GtkWidget * dialog;
	GtkSizeGroup * group;
	GtkWidget * vbox;
	GtkWidget * hbox;
	GtkWidget * widget;
	char * p;
	time_t t;

	if(pdfviewer->pdf == NULL)
		return;
	dialog = gtk_dialog_new_with_buttons(_("Properties of FIXME"),
			GTK_WINDOW(pdfviewer->window),
			GTK_DIALOG_MODAL | GTK_DIALOG_DESTROY_WITH_PARENT,
			GTK_STOCK_CLOSE, GTK_RESPONSE_CLOSE, NULL);
	gtk_window_set_default_size(GTK_WINDOW(dialog), 300, 200);
	group = gtk_size_group_new(GTK_SIZE_GROUP_HORIZONTAL);
#if GTK_CHECK_VERSION(2, 14, 0)
	vbox = gtk_dialog_get_content_area(GTK_DIALOG(dialog));
#else
	vbox = dialog->vbox;
#endif
	gtk_box_set_spacing(GTK_BOX(vbox), 4);
	/* title */
	widget = gtk_entry_new();
	if((p = poppler_document_get_title(pdfviewer->pdf->document)) != NULL)
		gtk_entry_set_text(GTK_ENTRY(widget), p);
	gtk_editable_set_editable(GTK_EDITABLE(widget), FALSE);
	gtk_box_pack_start(GTK_BOX(vbox), widget, FALSE, TRUE, 0);
	free(p);
	/* author */
	p = poppler_document_get_author(pdfviewer->pdf->document);
	hbox = _properties_label(pdfviewer, group, "Author: ", p);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	free(p);
	/* subject */
	p = poppler_document_get_subject(pdfviewer->pdf->document);
	hbox = _properties_label(pdfviewer, group, "Subject: ", p);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	free(p);
	/* keywords */
	p = poppler_document_get_keywords(pdfviewer->pdf->document);
	hbox = _properties_label(pdfviewer, group, "Keywords: ", p);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	free(p);
	/* creator */
	p = poppler_document_get_creator(pdfviewer->pdf->document);
	hbox = _properties_label(pdfviewer, group, "Creator: ", p);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	free(p);
	/* producer */
	p = poppler_document_get_producer(pdfviewer->pdf->document);
	hbox = _properties_label(pdfviewer, group, "Producer: ", p);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	free(p);
	/* creation time */
	t = poppler_document_get_creation_date(pdfviewer->pdf->document);
	hbox = _properties_label_date(pdfviewer, group, "Created on: ", t);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	/* modification time */
	t = poppler_document_get_modification_date(pdfviewer->pdf->document);
	hbox = _properties_label_date(pdfviewer, group, "Modified on: ", t);
	gtk_box_pack_start(GTK_BOX(vbox), hbox, FALSE, TRUE, 0);
	gtk_widget_show_all(vbox);
	gtk_dialog_run(GTK_DIALOG(dialog));
	gtk_widget_destroy(dialog);
}

static GtkWidget * _properties_label(PDFviewer * pdfviewer,
		GtkSizeGroup * group, char const * label, char const * value)
{
	GtkWidget * hbox;
	GtkWidget * widget;

	hbox = gtk_hbox_new(FALSE, 4);
	widget = gtk_label_new(label);
	gtk_widget_modify_font(widget, pdfviewer->bold);
	gtk_misc_set_alignment(GTK_MISC(widget), 0.0, 0.5);
	gtk_size_group_add_widget(group, widget);
	gtk_box_pack_start(GTK_BOX(hbox), widget, FALSE, TRUE, 0);
	widget = gtk_label_new((value != NULL) ? value : "");
	gtk_label_set_ellipsize(GTK_LABEL(widget), PANGO_ELLIPSIZE_END);
	gtk_misc_set_alignment(GTK_MISC(widget), 0.0, 0.5);
	gtk_box_pack_start(GTK_BOX(hbox), widget, TRUE, TRUE, 0);
	return hbox;
}

static GtkWidget * _properties_label_date(PDFviewer * pdfviewer,
		GtkSizeGroup * group, char const * label, time_t t)
{
	char buf[256];
	struct tm tm;

	localtime_r(&t, &tm);
	strftime(buf, sizeof(buf), "%b %d %Y, %H:%M:%S", &tm);
	return _properties_label(pdfviewer, group, label, buf);
}


/* pdf_open */
int pdf_open(PDFviewer * pdfviewer, const char * filename)
{
	gchar * uri;
	gchar * p;
	PDF * pdf;
	GError * error = NULL;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s(\"%s\")\n", __func__, uri);
#endif
	if(filename == NULL)
		/* XXX report error */
		return -1;
	if(filename[0] == '/')
		uri = g_strdup_printf("%s%s", "file://", filename);
	else
	{
		p = g_get_current_dir();
		uri = g_strdup_printf("%s%s/%s", "file://", p, filename);
		g_free(p);
	}
	pdf = g_new0(PDF, 1);
	if(uri == NULL || pdf == NULL)
	{
		g_free(pdf);
		g_free(uri);
		/* XXX report error */
		return -1;
	}
	pdf->document = poppler_document_new_from_file(uri, NULL, &error);
	g_free(uri);
	if(pdf->document == NULL)
	{
		if(error != NULL)
		{
			fprintf(stderr, PROGNAME ": %s: %s\n", filename,
					error->message);
			g_error_free(error);
		}
		g_free(pdf);
		return -1;
	}
	/* close the current document if any was opened */
	pdf_close(pdfviewer);
	pdfviewer->pdf = pdf;
	pdf->pages = poppler_document_get_n_pages(pdf->document);
	pdf_update_current(pdfviewer, '=', 0);
/*	pdfviewer->pdf->scale = 1.0; */	
	pdf_load_page(pdfviewer);
	return 0;
}


/* pdfviewer_open_dialog */
int pdfviewer_open_dialog(PDFviewer * pdfviewer)
{
	int ret;
	GtkWidget * dialog;
	GtkFileFilter * filter;
	char * filename = NULL;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
	dialog = gtk_file_chooser_dialog_new(_("Open file..."),
			GTK_WINDOW(pdfviewer->window),
			GTK_FILE_CHOOSER_ACTION_OPEN,
			GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,
			GTK_STOCK_OPEN, GTK_RESPONSE_ACCEPT, NULL);
	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter, _("PDF documents"));
	gtk_file_filter_add_mime_type(filter, "application/pdf");
	gtk_file_chooser_add_filter(GTK_FILE_CHOOSER(dialog), filter);
	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter, _("All files"));
	gtk_file_filter_add_pattern(filter, "*");
	gtk_file_chooser_add_filter(GTK_FILE_CHOOSER(dialog), filter);
	if(gtk_dialog_run(GTK_DIALOG(dialog)) == GTK_RESPONSE_ACCEPT)
		filename = gtk_file_chooser_get_filename(GTK_FILE_CHOOSER(
					dialog));
	gtk_widget_destroy(dialog);
	if(filename == NULL)
		return 0;
	ret = pdfviewer_open(pdfviewer, filename);
	g_free(filename);
	return ret;
}


/* pdfviewer_show_preferences */
void pdfviewer_show_preferences(PDFviewer * pdfviewer, gboolean show)
{
	/* FIXME implement */
}


/* pdf_close */
void pdf_close(PDFviewer * pdfviewer)
{
	GdkWindow * window;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
#if GTK_CHECK_VERSION(2, 14, 0)
	window = gtk_widget_get_window(pdfviewer->view);
#else
	window = pdfviewer->view->window;
#endif
	if(window != NULL)
		gdk_window_clear(window);
	if(pdfviewer->pdf != NULL)
		free(pdfviewer->pdf);
	pdfviewer->pdf = NULL;
}


/* pdf_load_page */
void pdf_load_page(PDFviewer * pdfviewer)
{
	PopplerPage *page;
	cairo_t *cr;
	gdouble width, height;
	GtkAllocation view_allocation;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
	if((page = poppler_document_get_page(pdfviewer->pdf->document,
					pdfviewer->pdf->current)) == NULL)
		/* FIXME prevent this from happening but keep the check in */
		return;
	poppler_page_get_size(page, &width, &height);

	if(!pdfviewer->pdf->scale) {
		/* gdk_drawable_get_size(gtk_widget_get_window(pdfviewer->view), &w, &h); */
#ifdef DEBUG
		fprintf(stderr, "DEBUG: %s() scale not set!\n", __func__);
#endif
#if GTK_CHECK_VERSION(2, 18, 0)
		gtk_widget_get_allocation(pdfviewer->view, &view_allocation);
		pdfviewer->pdf->scale = ((view_allocation.width - 20) / width); 
#else
		/* FIXME implement or re-work */
#endif
#if 0
		pdfviewer->pdf->scale = (view_allocation.height / height); /* view whole page */
#endif
	}

	gtk_statusbar_push(GTK_STATUSBAR(pdfviewer->statusbar),
		gtk_statusbar_get_context_id(
			GTK_STATUSBAR(pdfviewer->statusbar), "read-page"),
		g_strdup_printf(_("Page %d/%d"),
			pdfviewer->pdf->current + 1, pdfviewer->pdf->pages));

	if (pdfviewer->pdf->surface)
		cairo_surface_destroy (pdfviewer->pdf->surface);
	pdfviewer->pdf->surface = NULL;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s() scale: %f\n", __func__,
			pdfviewer->pdf->scale);
#endif
	pdfviewer->pdf->surface = cairo_image_surface_create(
		CAIRO_FORMAT_ARGB32, ceil(pdfviewer->pdf->scale * width),
		ceil(pdfviewer->pdf->scale * height));
	cr = cairo_create(pdfviewer->pdf->surface);
	cairo_save(cr);
	cairo_scale(cr, pdfviewer->pdf->scale, pdfviewer->pdf->scale);
	poppler_page_render(page, cr);
	cairo_restore(cr);
	cairo_destroy(cr);
	g_object_unref(page);

	g_signal_connect(pdfviewer->view, "expose-event", G_CALLBACK(
				pdf_render_area), pdfviewer->pdf);

	gtk_widget_set_size_request(pdfviewer->view,
		pdfviewer->pdf->scale * ceil(width),
		pdfviewer->pdf->scale * ceil(height));
	gtk_widget_queue_draw(pdfviewer->view);
}


/* pdf_render_area */
void pdf_render_area(GtkWidget *area, GdkEventExpose *event, void * data)
{
	PDF * pdf = data;
	GdkWindow * window;
        cairo_t *cr;

#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
#if GTK_CHECK_VERSION(2, 14, 0)
	window = gtk_widget_get_window(area);
#else
	window = area->window;
#endif
	if(window != NULL)
		gdk_window_clear(window);
	if(pdf == NULL)
		return;
        cr = gdk_cairo_create(window);
        cairo_set_source_surface(cr, pdf->surface, 0, 0);
        cairo_paint(cr);
        cairo_destroy(cr);
}


/* pdf_update_current */
void pdf_update_current(PDFviewer * pdfviewer, const char op, int n)
{
#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
	switch(op)
	{
		case '=':	if((n >= 0) && 
				  (n <= (pdfviewer->pdf->pages - 1)))
					pdfviewer->pdf->current = n;
					break;
		case '+':	if((pdfviewer->pdf->current + n)
				   <= pdfviewer->pdf->pages)
					pdfviewer->pdf->current =
						pdfviewer->pdf->current + n;
					break;
		case '-':	if((pdfviewer->pdf->current - n) >= 0)	
					pdfviewer->pdf->current =
						pdfviewer->pdf->current - n;
					break;
	}
	set_prevnext_sensitivity(pdfviewer);
}

/* set_prevnext_sensitivity */
void set_prevnext_sensitivity(PDFviewer * pdfviewer)
{
	GtkToolbar * toolbar = GTK_TOOLBAR(pdfviewer->toolbar);
	gboolean farbefore, prev, next, farafter;

	if(pdfviewer->pdf != NULL) {
		/* XXX s/5/preferences/ */
		farbefore = (pdfviewer->pdf->current > 5) ? TRUE : FALSE;
		prev = (pdfviewer->pdf->current > 0) ? TRUE : FALSE;
		next = (pdfviewer->pdf->current + 1 < pdfviewer->pdf->pages)
			? TRUE : FALSE;
		farafter = (pdfviewer->pdf->current + 5 < pdfviewer->pdf->pages)
			? TRUE : FALSE;
	} else {
		farbefore = FALSE;
		prev = FALSE;
		next = FALSE;
		farafter = FALSE;
	}
	gtk_widget_set_sensitive(GTK_WIDGET(
		gtk_toolbar_get_nth_item(toolbar, 2)), farbefore);
	gtk_widget_set_sensitive(GTK_WIDGET(
		gtk_toolbar_get_nth_item(toolbar, 3)), prev);
	gtk_widget_set_sensitive(GTK_WIDGET(
		gtk_toolbar_get_nth_item(toolbar, 4)), next);
	gtk_widget_set_sensitive(GTK_WIDGET(
		gtk_toolbar_get_nth_item(toolbar, 5)), farafter);
}


/* pdf_update_scale */
void pdf_update_scale(PDFviewer * pdfviewer, const char op, double n)
{
#ifdef DEBUG
	fprintf(stderr, "DEBUG: %s('%c', %f)\n", __func__, op, n);
#endif
	switch(op)
	{
		case '=':
			pdfviewer->pdf->scale = n;
			break;
		case '+':
			pdfviewer->pdf->scale = pdfviewer->pdf->scale + n;
			break;
		case '-':
			if((pdfviewer->pdf->scale - n) > 0)	
				pdfviewer->pdf->scale =
					pdfviewer->pdf->scale - n;
			break;
	}
	pdf_load_page(pdfviewer);
}


/* private */
/* functions */
/* pdfviewer_set_title */
static void _pdfviewer_set_title(PDFviewer * pdfviewer)
{
	char const * title = _("(Untitled)");
	char * p = NULL;
	char buf[256];

	if(pdfviewer->pdf != NULL)
		if((p = poppler_document_get_title(pdfviewer->pdf->document))
				!= NULL)
			/* FIXME use the filename instead */
			title = p;
	snprintf(buf, sizeof(buf), "%s%s", _("PDF viewer - "), title);
	gtk_window_set_title(GTK_WINDOW(pdfviewer->window), buf);
	free(p);
}