#include <poppler/glib/poppler.h>
#include <gtk/gtk.h>

static GtkWidget *title_entry, *author_entry, *file_chooser;
static PopplerDocument *current_document = NULL;

static void
show_error (const gchar *format, ...)
{
	va_list args;
	gchar *msg;

	va_start (args, format);
	msg = g_strdup_vprintf (format, args);

	g_print ("%s\n", msg);
	g_free (msg);
}

static void
move_file (const gchar *source, const gchar *dest)
{
	GFile *f_source, *f_dest;
	GError *error = NULL;

	f_source = g_file_new_for_uri (source);
	f_dest = g_file_new_for_uri (dest);

	if (!g_file_move (f_source, f_dest, G_FILE_COPY_OVERWRITE, NULL, NULL, NULL, &error)) {
		show_error ("Couldn't move %s to %s: %s", source, dest, error->message);
		g_error_free (error);
	}
}

static void
entry_changed_cb (GtkEditable *editable, gpointer user_data)
{
	gtk_widget_set_sensitive (GTK_WIDGET (user_data), TRUE);
}

static GtkWidget *
create_entry (const gchar *title, GtkWidget *table, gint x1, gint x2, gint y1, gint y2, GtkWidget *button)
{
	GtkWidget *label, *entry;

	label = gtk_label_new (title);
	gtk_table_attach (GTK_TABLE (table), label, x1, x2, y1, y2, GTK_FILL, GTK_FILL, 3, 3);
	gtk_widget_show (label);

	entry = gtk_entry_new ();
	g_signal_connect (G_OBJECT (entry), "changed",
			  G_CALLBACK (entry_changed_cb), button);
	gtk_table_attach (GTK_TABLE (table), entry, x2, x2 + 1, y1, y2, GTK_FILL, GTK_FILL, 3, 3);
	gtk_widget_set_sensitive (entry, FALSE);
	gtk_widget_show (entry);

	return entry;
}

static void
file_selected_cb (GtkFileChooserButton *button, gpointer user_data)
{
	gchar *file_uri;

	gtk_widget_set_sensitive (title_entry, TRUE);
	gtk_widget_set_sensitive (author_entry, TRUE);
	gtk_widget_set_sensitive (GTK_WIDGET (user_data), FALSE);

	if (current_document != NULL)
		g_object_unref (current_document);

	/* Load the PDF */
	file_uri = gtk_file_chooser_get_uri (GTK_FILE_CHOOSER (button));
	if (file_uri) {
		GError *error = NULL;

		current_document = poppler_document_new_from_file (file_uri, NULL, &error);
		if (current_document != NULL) {
			gtk_entry_set_text (GTK_ENTRY (title_entry),
					    poppler_document_get_title (current_document) ? 
					    poppler_document_get_title (current_document) : "");
			gtk_entry_set_text (GTK_ENTRY (author_entry),
					    poppler_document_get_author (current_document) ?
					    poppler_document_get_author (current_document) : "");
		} else {
			show_error ("Error loading %s: %s", file_uri, error->message);
			g_error_free (error);
		}

		g_free (file_uri);
	}
}

static void
save_clicked_cb (GtkButton *button, gpointer user_data)
{
	gchar *original_file, *temp_file;

	g_return_if_fail (POPPLER_IS_DOCUMENT (current_document));

	original_file = gtk_file_chooser_get_uri (GTK_FILE_CHOOSER (file_chooser));
	if (original_file != NULL) {
		GError *error = NULL;

		temp_file = g_strdup_printf ("%s.tmp", original_file);

		poppler_document_set_title (current_document, gtk_entry_get_text (GTK_ENTRY (title_entry)));
		poppler_document_set_author (current_document, gtk_entry_get_text (GTK_ENTRY (author_entry)));

		if (poppler_document_save (current_document, temp_file, &error)) {
			move_file (temp_file, original_file);
			gtk_widget_set_sensitive (GTK_WIDGET (button), FALSE);
		} else {
			show_error ("Error saving %s: %s", original_file, error->message);
			g_error_free (error);
		}

		g_free (temp_file);
	}

	g_free (original_file);
}

int
main (int argc, char *argv[])
{
	GtkWidget *dialog, *table, *label, *button;

	gtk_init (&argc, &argv);

	/* Create the main dialog */
	dialog = gtk_dialog_new_with_buttons ("PDF Fixer", NULL, 0,
					      GTK_STOCK_CLOSE, GTK_RESPONSE_CLOSE,
					      NULL);
	g_signal_connect (G_OBJECT (dialog), "response",
			  G_CALLBACK (gtk_main_quit), NULL);

	table = gtk_table_new (3, 4, FALSE);
	gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))), table, TRUE, TRUE, 3);
	gtk_widget_show (table);

	button = gtk_button_new_from_stock (GTK_STOCK_SAVE);
	gtk_widget_set_sensitive (button, FALSE);
	g_signal_connect (G_OBJECT (button), "clicked",
			  G_CALLBACK (save_clicked_cb), NULL);
	gtk_table_attach (GTK_TABLE (table), button, 3, 4, 3, 4, GTK_FILL, GTK_FILL, 3, 3);
	gtk_widget_show (button);

	file_chooser = gtk_file_chooser_button_new ("Select PDF file", GTK_FILE_CHOOSER_ACTION_OPEN);
	g_signal_connect (G_OBJECT (file_chooser), "selection-changed",
			  G_CALLBACK (file_selected_cb), button);
	gtk_table_attach (GTK_TABLE (table), file_chooser, 0, 4, 0, 1, GTK_FILL | GTK_EXPAND, GTK_FILL, 3, 3);
	gtk_widget_show (file_chooser);

	title_entry = create_entry ("Title", table, 1, 2, 1, 2, button);
	author_entry = create_entry ("Author", table, 1, 2, 2, 3, button);

	/* Run the application */
	gtk_widget_show (dialog);
	gtk_main ();
					      
	return 0;
}