move zathura_get_document_size to document.c

It makes more sense, plus now the document knows about the page layout
and can do the computation.

document.c

@@ -427,6 +427,26 @@ zathura_document_get_cell_size(zathura_document_t* document,
 
 }
 
+void
+zathura_document_get_document_size(zathura_document_t* document,
+                                   unsigned int* height, unsigned int* width)
+{
+  g_return_if_fail(document != NULL && height != NULL && width != NULL);
+
+
+  unsigned int npag  = zathura_document_get_number_of_pages(document);
+  unsigned int ncol  = zathura_document_get_pages_per_row(document);
+  unsigned int c0    = zathura_document_get_first_page_column(document);
+  unsigned int nrow  = (npag + c0 - 1 + ncol - 1) / ncol;  /* number of rows */
+  unsigned int pad   = zathura_document_get_page_padding(document);
+
+  unsigned int cell_height=0, cell_width=0;
+  zathura_document_get_cell_size(document, &cell_height, &cell_width);
+
+  *width  = ncol * cell_width + (ncol - 1) * pad;
+  *height = nrow * cell_height + (nrow - 1) * pad;
+}
+
 void
 zathura_document_set_page_layout(zathura_document_t* document, unsigned int page_padding,
                                  unsigned int pages_per_row, unsigned int first_page_column)

document.h

@@ -188,6 +188,18 @@ void zathura_document_set_data(zathura_document_t* document, void* data);
 void zathura_document_get_cell_size(zathura_document_t* document,
                                     unsigned int* height, unsigned int* width);
 
+/**
+ * Compute the size of the entire document to be displayed (in pixels), taking
+ * into account the scale, the layout of the pages, and the padding between
+ * them. It should be equal to the allocation of zathura->ui.page_widget once
+ * it's shown.
+ *
+ * @param[in]  document               The document
+ * @param[out] height,width           The height and width of the document
+ */
+void zathura_document_get_document_size(zathura_document_t* document,
+                                        unsigned int* height, unsigned int* width);
+
 /**
  * Sets the layout of the pages in the document
  *

shortcuts.c

@@ -144,8 +144,7 @@ sc_adjust_window(girara_session_t* session, girara_argument_t* argument,
 
   zathura_document_set_scale(zathura->document, scale);
   zathura_document_get_cell_size(zathura->document, &cell_height, &cell_width);
-  zathura_get_document_size(zathura, cell_height, cell_width,
-                            &document_height, &document_width);
+  zathura_document_get_document_size(zathura->document, &document_height, &document_width);
 
   double page_ratio   = (double)cell_height / (double)document_width;
   double window_ratio = (double)height / (double)width;
@@ -162,8 +161,7 @@ sc_adjust_window(girara_session_t* session, girara_argument_t* argument,
     if (show_vscrollbar) {
       /* If the document is taller than the view, there's a vertical
        * scrollbar; we need to substract its width from the view's width. */
-      zathura_get_document_size(zathura, cell_height, cell_width,
-                                &document_height, &document_width);
+      zathura_document_get_document_size(zathura->document, &document_height, &document_width);
       if (height < document_height) {
         GtkWidget* vscrollbar = gtk_scrolled_window_get_vscrollbar(
             GTK_SCROLLED_WINDOW(session->gtk.view));

utils.c

@@ -262,42 +262,6 @@ page_calc_height_width(zathura_document_t* document, double height, double width
   return real_scale;
 }
 
-void
-zathura_get_document_size(zathura_t* zathura,
-                          unsigned int cell_height, unsigned int cell_width,
-                          unsigned int* height, unsigned int* width)
-{
-  g_return_if_fail(zathura != NULL && zathura->document != NULL &&
-                   height != NULL && width != NULL);
-
-  unsigned int pages_per_row = 1;
-  girara_setting_get(zathura->ui.session, "pages-per-row", &pages_per_row);
-  if (pages_per_row == 0)
-    pages_per_row = 1;
-
-  unsigned int first_page_column = 1;
-  girara_setting_get(zathura->ui.session, "first-page-column", &first_page_column);
-  if (first_page_column < 1)
-    first_page_column = 1;
-  if (first_page_column > pages_per_row)
-    first_page_column = (first_page_column - 1) % pages_per_row + 1;
-
-  int padding = 1;
-  girara_setting_get(zathura->ui.session, "page-padding", &padding);
-
-  double scale = zathura_document_get_scale(zathura->document);
-
-  cell_height = ceil(cell_height * scale);
-  cell_width  = ceil(cell_width * scale);
-
-  *width = pages_per_row * cell_width + (pages_per_row - 1) * padding;
-  unsigned int effective_number_of_pages =
-    zathura_document_get_number_of_pages(zathura->document) +
-    first_page_column - 1;
-  unsigned int rows = effective_number_of_pages / pages_per_row +
-                     (effective_number_of_pages % pages_per_row ? 1 : 0);
-  *height = rows * cell_height + (rows - 1) * padding;
-}
 
 GtkWidget*
 zathura_page_get_widget(zathura_t* zathura, zathura_page_t* page)

utils.h

@@ -99,23 +99,6 @@ double
 page_calc_height_width(zathura_document_t* document, double height, double width,
                        unsigned int* page_height, unsigned int* page_width, bool rotate);
 
-/**
- * Compute the size of the entire document to be displayed (in pixels), taking
- * into account the scale, the layout of the pages, and the padding between
- * them. It should be equal to the allocation of zathura->ui.page_widget once
- * it's shown.
- *
- * @param[in]  zathura                The zathura instance
- * @param[in]  cell_height,cell_width The height and width of a cell containing
- *                                    a single page; it should be obtained
- *                                    using zathura_document_get_cell_size()
- *                                    with the document scale set to 1.0
- * @param[out] height,width           The height and width of the document
- */
-void zathura_get_document_size(zathura_t* zathura,
-                               unsigned int cell_height, unsigned int cell_width,
-                               unsigned int* height, unsigned int* width);
-
 /**
  * Returns the page widget of the page
  *