EDateEdit: Force 24 hour format for locales without am/pm equivalents

Some locales do not provide equivalents for am/pm (the "%p" of strftime),
thus when the user has set 12 hour format in Preferences, then the am
and pm times are the same, which confuses the widget, especially
in the appointment editor, making it hard (like impossible) to enter
pm times by selection in the time combo. An example locale is de_DE.

1 files changed, 47 insertions, 27 deletions

diff --git a/e-util/e-dateedit.c b/e-util/e-dateedit.c
index 30025557c0..63e19c80ee 100644
--- a/e-util/e-dateedit.c
+++ b/e-util/e-dateedit.c
@@ -1687,6 +1687,39 @@ hide_date_popup (EDateEdit *dedit)
 	}
 }
 
+/* some locales may not define am/pm equivalents for '%p',
+   thus force 24 hour format for these, otherwise the am/pm
+   time clashes */
+static gboolean
+date_edit_use_24_hour_format (gboolean use_24_hour_format)
+{
+	struct tm tmp_tm = { 0 };
+	gchar buffer[40];
+
+	if (use_24_hour_format)
+		return TRUE;
+
+	/* Fill the struct tm with some sane values. */
+	tmp_tm.tm_year = 2000;
+	tmp_tm.tm_mon = 0;
+	tmp_tm.tm_mday = 1;
+	tmp_tm.tm_sec  = 0;
+	tmp_tm.tm_isdst = 0;
+	tmp_tm.tm_hour = 1;
+	tmp_tm.tm_min  = 0;
+
+	if (e_utf8_strftime (buffer, sizeof (buffer), "%p", &tmp_tm) == 0)
+		return TRUE;
+
+	tmp_tm.tm_hour = 13;
+	tmp_tm.tm_min  = 0;
+
+	if (e_utf8_strftime (buffer, sizeof (buffer), "%p", &tmp_tm) == 0)
+		return TRUE;
+
+	return use_24_hour_format;
+}
+
 /* Clears the time popup and rebuilds it using the lower_hour, upper_hour
  * and use_24_hour_format settings. */
 static void
@@ -1697,7 +1730,8 @@ rebuild_time_popup (EDateEdit *dedit)
 	GtkListStore *list_store;
 	GtkTreeIter iter;
 	gchar buffer[40];
-	struct tm tmp_tm;
+	gboolean use_24_hour_format;
+	struct tm tmp_tm = { 0 };
 	gint hour, min;
 
 	priv = dedit->priv;
@@ -1713,6 +1747,8 @@ rebuild_time_popup (EDateEdit *dedit)
 	tmp_tm.tm_sec  = 0;
 	tmp_tm.tm_isdst = 0;
 
+	use_24_hour_format = date_edit_use_24_hour_format (priv->use_24_hour_format);
+
 	for (hour = priv->lower_hour; hour <= priv->upper_hour; hour++) {
 
 		/* We don't want to display midnight at the end,
@@ -1727,24 +1763,14 @@ rebuild_time_popup (EDateEdit *dedit)
 			tmp_tm.tm_hour = hour;
 			tmp_tm.tm_min  = min;
 
-			if (priv->use_24_hour_format)
-				/* This is a strftime() format.
-				 * %H = hour (0-23), %M = minute. */
-				e_time_format_time (
-					&tmp_tm, 1, 0,
-					buffer, sizeof (buffer));
-			else
-				/* This is a strftime() format.
-				 * %I = hour (1-12), %M = minute,
-				 * %p = am/pm string. */
-				e_time_format_time (
-					&tmp_tm, 0, 0,
-					buffer, sizeof (buffer));
+			e_time_format_time (
+				&tmp_tm, use_24_hour_format, 0,
+				buffer, sizeof (buffer));
 
 			/* For 12-hour am/pm format, we want space padding,
 			 * not zero padding. This can be done with strftime's
 			 * %l, but it's a potentially unportable extension. */
-			if (!priv->use_24_hour_format && buffer[0] == '0')
+			if (use_24_hour_format && buffer[0] == '0')
 				buffer[0] = ' ';
 
 			gtk_list_store_append (list_store, &iter);
@@ -2105,7 +2131,7 @@ e_date_edit_update_time_entry (EDateEdit *dedit)
 	} else {
 		GtkTreeModel *model;
 		GtkTreeIter iter;
-		gboolean valid;
+		gboolean valid, use_24_hour_format;
 		gchar *b;
 
 		/* Set these to reasonable values just in case. */
@@ -2119,21 +2145,15 @@ e_date_edit_update_time_entry (EDateEdit *dedit)
 		tmp_tm.tm_sec = 0;
 		tmp_tm.tm_isdst = -1;
 
-		if (priv->use_24_hour_format)
-			/* This is a strftime() format.
-			 * %H = hour (0-23), %M = minute. */
-			e_time_format_time (
-				&tmp_tm, 1, 0, buffer, sizeof (buffer));
-		else
-			/* This is a strftime() format.
-			 * %I = hour (1-12), %M = minute, %p = am/pm. */
-			e_time_format_time (
-				&tmp_tm, 0, 0, buffer, sizeof (buffer));
+		use_24_hour_format = date_edit_use_24_hour_format (priv->use_24_hour_format);
+
+		e_time_format_time (
+			&tmp_tm, use_24_hour_format, 0, buffer, sizeof (buffer));
 
 		/* For 12-hour am/pm format, we want space padding, not
 		 * zero padding.  This can be done with strftime's %l,
 		 * but it's a potentially unportable extension. */
-		if (!priv->use_24_hour_format && buffer[0] == '0')
+		if (!use_24_hour_format && buffer[0] == '0')
 			buffer[0] = ' ';
 
 		gtk_entry_set_text (GTK_ENTRY (child), buffer);