Switch from date based to dive trip based grouping

Linus HATED the date based grouping - too much wasted space visually
("three levels of grouping are way too much") and asked for dive trip
based grouping instead.

This is a quick change to do just that, with an assumption that no
dive in 3 days means it's a new trip.

This also changes the summary entry to display a location for the trip,
for now we pick the location of the (chronologically) first dive of the
trip.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

diff --git a/divelist.c b/divelist.c
index a4221f7b95b6dd5b410fa42c46eeb62aab4b57d0..5b4ef0a1099678ce8d8bcae3b88125a2290c111e 100644 (file)
--- a/divelist.c
+++ b/divelist.c
@@ -53,10 +53,8 @@ enum {
 };
 
 /* magic numbers that indicate (as negative values) model entries that
- * are summary entries for day / month / year */
-#define NEW_DAY 1
-#define NEW_MON 2
-#define NEW_YR  3
+ * are summary entries for a divetrip */
+#define NEW_TRIP 1
 
 #ifdef DEBUG_MODEL
 static gboolean dump_model_entry(GtkTreeModel *model, GtkTreePath *path,
@@ -240,23 +238,13 @@ static void date_data_func(GtkTreeViewColumn *col,
 
        tm = gmtime(&when);
        switch(idx) {
-       case -NEW_DAY:
+       case -NEW_TRIP:
                snprintf(buffer, sizeof(buffer),
-                       "%s, %s %d, %d",
+                       "Trip %s, %s %d, %d",
                        weekday(tm->tm_wday),
                        monthname(tm->tm_mon),
                        tm->tm_mday, tm->tm_year + 1900);
                break;
-       case -NEW_MON:
-               snprintf(buffer, sizeof(buffer),
-                       "%s %d",
-                       monthname(tm->tm_mon),
-                       tm->tm_year + 1900);
-               break;
-       case -NEW_YR:
-               snprintf(buffer, sizeof(buffer),
-                       "%d", tm->tm_year + 1900);
-               break;
        default:
                snprintf(buffer, sizeof(buffer),
                        "%s, %s %d, %d %02d:%02d",
@@ -748,22 +736,20 @@ void update_dive_list_col_visibility(void)
        return;
 }
 
-static int new_date(struct dive *dive, struct dive **last_dive, const int flag, time_t *tm_date)
+/* random heuristic - not diving in three days implies new dive trip */
+#define TRIP_THRESHOLD 3600*24*3
+static int new_group(struct dive *dive, struct dive **last_dive, time_t *tm_date)
 {
        if (!last_dive)
                return TRUE;
        if (*last_dive) {
                struct dive *ldive = *last_dive;
-               struct tm tm1, tm2;
-               (void) gmtime_r(&dive->when, &tm1);
-               (void) gmtime_r(&ldive->when, &tm2);
-               if (tm1.tm_year == tm2.tm_year &&
-                       (tm1.tm_mon == tm2.tm_mon || flag > NEW_MON) &&
-                       (tm1.tm_mday == tm2.tm_mday || flag > NEW_DAY))
+               if (abs(dive->when - ldive->when) < TRIP_THRESHOLD) {
+                       *last_dive = dive;
                        return FALSE;
+               }
        }
-       if (flag == NEW_DAY)
-               *last_dive = dive;
+       *last_dive = dive;
        if (tm_date) {
                struct tm *tm1 = gmtime(&dive->when);
                tm1->tm_sec = 0;
@@ -776,10 +762,12 @@ static int new_date(struct dive *dive, struct dive **last_dive, const int flag,
 
 static void fill_dive_list(void)
 {
-       int i, j;
-       GtkTreeIter iter, parent_iter[NEW_YR + 2], *parents[NEW_YR + 2] = {NULL, };
+       int i;
+       GtkTreeIter iter, parent_iter;
        GtkTreeStore *liststore, *treestore;
        struct dive *last_dive = NULL;
+       struct dive *first_trip_dive = NULL;
+       struct dive *last_trip_dive = NULL;
        time_t dive_date;
 
        treestore = GTK_TREE_STORE(dive_list.treemodel);
@@ -789,23 +777,29 @@ static void fill_dive_list(void)
        while (--i >= 0) {
                struct dive *dive = dive_table.dives[i];
 
-               for (j = NEW_YR; j >= NEW_DAY; j--) {
-                       if (new_date(dive, &last_dive, j, &dive_date))
-                       {
-                               gtk_tree_store_append(treestore, &parent_iter[j], parents[j+1]);
-                               parents[j] = &parent_iter[j];
-                               gtk_tree_store_set(treestore, parents[j],
-                                               DIVE_INDEX, -j,
-                                               DIVE_NR, -j,
-                                               DIVE_DATE, dive_date,
-                                               DIVE_LOCATION, "",
-                                               DIVE_TEMPERATURE, 0,
-                                               DIVE_SAC, 0,
+               if (new_group(dive, &last_dive, &dive_date))
+               {
+                       /* make sure we display the first date of the trip in previous summary */
+                       if (first_trip_dive && last_trip_dive && last_trip_dive->when < first_trip_dive->when)
+                               gtk_tree_store_set(treestore, &parent_iter,
+                                               DIVE_DATE, last_trip_dive->when,
+                                               DIVE_LOCATION, last_trip_dive->location,
                                                -1);
-                       }
+                       first_trip_dive = dive;
+
+                       gtk_tree_store_append(treestore, &parent_iter, NULL);
+                       gtk_tree_store_set(treestore, &parent_iter,
+                                       DIVE_INDEX, -NEW_TRIP,
+                                       DIVE_NR, -NEW_TRIP,
+                                       DIVE_DATE, dive_date,
+                                       DIVE_LOCATION, dive->location,
+                                       DIVE_TEMPERATURE, 0,
+                                       DIVE_SAC, 0,
+                                       -1);
                }
+               last_trip_dive = dive;
                update_cylinder_related_info(dive);
-               gtk_tree_store_append(treestore, &iter, parents[NEW_DAY]);
+               gtk_tree_store_append(treestore, &iter, &parent_iter);
                gtk_tree_store_set(treestore, &iter,
                        DIVE_INDEX, i,
                        DIVE_NR, dive->number,