From 3373f7797901dbae1b33e8ed1f0f92cd4fc8fa5d Mon Sep 17 00:00:00 2001
From: Joshua Sled <jsled@asynchronous.org>
Date: Mon, 19 Feb 2007 22:08:57 +0000
Subject: [PATCH] Add a cmp() function for Recurrence (lists).

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@15631 57a11ea4-9604-0410-9ed3-97b8803252fd
---
 src/doc/sx.rst                             |  2 +-
 src/engine/Recurrence.c                    | 87 ++++++++++++++++++++++
 src/engine/Recurrence.h                    |  4 +
 src/gnome/gnc-sx-list-tree-model-adapter.c |  3 +-
 4 files changed, 93 insertions(+), 3 deletions(-)

diff --git a/src/doc/sx.rst b/src/doc/sx.rst
index 2a6f4b137a..b4c67da926 100644
--- a/src/doc/sx.rst
+++ b/src/doc/sx.rst
@@ -138,7 +138,7 @@ TODO
     - [x] gnc_sxed_update_cal
     - [x] gnc_sxed_save_sx
   - sx list
-    - [ ] recurrence_cmp(...)
+    - [x] recurrence_cmp(...)
     - [x] More compact recurrenceListToString(...).
   - [ ] remove FreqSpec code
     - [ ] SX code
diff --git a/src/engine/Recurrence.c b/src/engine/Recurrence.c
index 3bbffa4494..57fc55eefc 100644
--- a/src/engine/Recurrence.c
+++ b/src/engine/Recurrence.c
@@ -577,3 +577,90 @@ rtn:
     return g_string_free(buf, FALSE);
 }
 
+/**
+ * The ordering, in increasing degrees of frequent-ness:
+ *
+ *   day < week < {nth-weekday < month < end-month, last_weekday} < year < once
+ *
+ * all the monthly types are basically together, but are broken down
+ * internally cause they have to be ordered somehow.
+ **/
+static int cmp_order_indexes[] =
+{
+    6, // PERIOD_ONCE
+    1, // PERIOD_DAY
+    2, // PERIOD_WEEK
+    // 3, // "semi-monthly" ... Note that this isn't presently used, just the
+    //    // way the code worked out. :(
+    4, // PERIOD_MONTH
+    4, // PERIOD_END_OF_MONTH
+    4, // PERIOD_NTH_WEEKDAY
+    4, // PERIOD_LAST_WEEKDAY
+    5, // PERIOD_YEAR
+};
+
+static int cmp_monthly_order_indexes[] =
+{
+    -1, // PERIOD_ONCE
+    -1, // PERIOD_DAY
+    -1, // PERIOD_WEEK
+    2, // PERIOD_MONTH
+    3, // PERIOD_END_OF_MONTH
+    1, // PERIOD_NTH_WEEKDAY
+    4, // PERIOD_LAST_WEEKDAY
+    -1, // PERIOD_YEAR
+};
+
+int
+recurrenceCmp(Recurrence *a, Recurrence *b)
+{
+    PeriodType period_a, period_b;
+    int a_order_index, b_order_index;
+
+    g_return_val_if_fail(a != NULL && b != NULL, 0);
+    g_return_val_if_fail(a != NULL, 1);
+    g_return_val_if_fail(b != NULL, -1);
+
+    period_a = recurrenceGetPeriodType(a);
+    period_b = recurrenceGetPeriodType(b);
+
+    a_order_index = cmp_order_indexes[period_a];
+    b_order_index = cmp_order_indexes[period_b];
+    if (a_order_index != b_order_index)
+    {
+        return a_order_index - b_order_index;
+    }
+    else if (a_order_index == cmp_order_indexes[PERIOD_MONTH])
+    {
+        // re-order intra-month options:
+        a_order_index = cmp_monthly_order_indexes[period_a];
+        b_order_index = cmp_monthly_order_indexes[period_b];
+        g_assert(a_order_index != -1 && b_order_index != -1);
+        if (a_order_index != b_order_index)
+            return a_order_index - b_order_index;
+    }
+    /* else { the basic periods are equal; compare the multipliers } */
+
+    {
+        int a_mult, b_mult;
+        a_mult = recurrenceGetMultiplier(a);
+        b_mult = recurrenceGetMultiplier(b);
+
+        return a_mult - b_mult;
+    }
+}
+
+int
+recurrenceListCmp(GList *a, GList *b)
+{
+    Recurrence *most_freq_a, *most_freq_b;
+
+    g_return_val_if_fail(g_list_length(a) != 0 && g_list_length(b) != 0, 0);
+    g_return_val_if_fail(g_list_length(a) != 0, -1);
+    g_return_val_if_fail(g_list_length(b) != 0, 1);
+
+    most_freq_a = (Recurrence*)g_list_nth_data(g_list_sort(a, (GCompareFunc)recurrenceCmp), 0);
+    most_freq_b = (Recurrence*)g_list_nth_data(g_list_sort(b, (GCompareFunc)recurrenceCmp), 0);
+
+    return recurrenceCmp(most_freq_a, most_freq_b);
+}
diff --git a/src/engine/Recurrence.h b/src/engine/Recurrence.h
index 5d1c26ff0f..4ddc946939 100644
--- a/src/engine/Recurrence.h
+++ b/src/engine/Recurrence.h
@@ -166,4 +166,8 @@ gboolean recurrenceListIsWeeklyMultiple(GList *recurrences);
  **/
 gchar *recurrenceListToCompactString(GList *recurrence_list);
 
+/** @return integer representing the relationship between @a a and @a b, with the semantics of qsort. **/
+int recurrenceCmp(Recurrence *a, Recurrence *b);
+int recurrenceListCmp(GList *a, GList *b);
+
 #endif  /* RECURRENCE_H */
diff --git a/src/gnome/gnc-sx-list-tree-model-adapter.c b/src/gnome/gnc-sx-list-tree-model-adapter.c
index c6c78ccbca..b66ed66faf 100644
--- a/src/gnome/gnc-sx-list-tree-model-adapter.c
+++ b/src/gnome/gnc-sx-list-tree-model-adapter.c
@@ -382,8 +382,7 @@ _freq_comparator(GtkTreeModel *model, GtkTreeIter *a, GtkTreeIter *b, gpointer u
     if (a_inst == NULL) return 1;
     if (b_inst == NULL) return -1;
 
-    return gnc_freq_spec_compare(xaccSchedXactionGetFreqSpec(a_inst->sx),
-                                 xaccSchedXactionGetFreqSpec(b_inst->sx));
+    return recurrenceListCmp(gnc_sx_get_schedule(a_inst->sx), gnc_sx_get_schedule(b_inst->sx));
 }
 
 static gint