[gnome-calendar] month-view: Use last cell to calculate multday event end

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 0b4119367a79f2c9946b38bdf64dccf3c0fcb253
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Wed Jun 26 11:01:36 2019 -0300

    month-view: Use last cell to calculate multday event end
    
    Instead of assuming all cells have the same width, use the last
    cell to figure out the width of the event with the traditional:
    
        event width = end.x2 - start.x1
        event width = (end.x1 + end.width) - start.x1
    
    https://gitlab.gnome.org/GNOME/gnome-calendar/issues/413

 src/views/gcal-month-view.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)
---
diff --git a/src/views/gcal-month-view.c b/src/views/gcal-month-view.c
index 64b4c982..e7c41418 100644
--- a/src/views/gcal-month-view.c
+++ b/src/views/gcal-month-view.c
@@ -581,7 +581,6 @@ allocate_multiday_events (GcalMonthView *self,
                           gint          *allocated_events_at_day)
 {
   GtkAllocation event_allocation;
-  GtkAllocation cell_allocation;
   GtkBorder margin;
   GList *l;
   gboolean is_rtl;
@@ -623,6 +622,9 @@ allocate_multiday_events (GcalMonthView *self,
           g_autoptr (GDateTime) dt_start = NULL;
           g_autoptr (GDateTime) dt_end = NULL;
           GcalEventBlock *block;
+          GtkAllocation first_cell_allocation;
+          GtkAllocation last_cell_allocation;
+          GtkWidget *last_month_cell;
           GtkWidget *month_cell;
           GList *aux;
           gdouble pos_x;
@@ -666,16 +668,19 @@ allocate_multiday_events (GcalMonthView *self,
             }
 
 
-          /*
-           * Retrieve the cell widget. On RTL languages, we use the last month cell as the starting
-           * point.
-           */
+          /* Retrieve the cell widget. On RTL languages, swap the first and last cells */
+          month_cell = self->month_cell[cell / 7][cell % 7];
+          last_month_cell = self->month_cell[last_block_cell / 7][last_block_cell % 7];
+
           if (is_rtl)
-            month_cell = self->month_cell[last_block_cell / 7][last_block_cell % 7];
-          else
-            month_cell = self->month_cell[cell / 7][cell % 7];
+            {
+              GtkWidget *aux = month_cell;
+              month_cell = last_month_cell;
+              last_month_cell = aux;
+            }
 
-          gtk_widget_get_allocation (month_cell, &cell_allocation);
+          gtk_widget_get_allocation (month_cell, &first_cell_allocation);
+          gtk_widget_get_allocation (last_month_cell, &last_cell_allocation);
 
           gtk_widget_set_child_visible (child_widget, TRUE);
 
@@ -703,9 +708,9 @@ allocate_multiday_events (GcalMonthView *self,
                                         &margin);
 
 
-          pos_x = cell_allocation.x + margin.left;
-          pos_y = cell_allocation.y + margin.top;
-          width = cell_allocation.width * length;
+          pos_x = first_cell_allocation.x + margin.left;
+          pos_y = first_cell_allocation.y + margin.top;
+          width = last_cell_allocation.x + last_cell_allocation.width - first_cell_allocation.x;
 
           remove_cell_border_and_padding (month_cell, &pos_x, &pos_y, &width);