Handle new dives correctly if trips exist

There is an interesting issue when adding new dives into a dive list with
existing trips. Since fill_dive_list walks the list backwards and trips
are determined by the timestamp of the first dive in a trip, it is
non-trivial to know when a dive is added if it should be part of an
existing trip or not. Let's say when we see the dive we can also see a
trip entry that starts four days earlier. Without looking forward in the
list of dives we cannot tell if this is a multi-day trip that this dive
would fit into, or if there is a break of more than tree days (our current
trip threshold).

Instead this commit adds a second scan of the dives in chronological order
that does the right thing for new dives.

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

dive.h

@@ -271,6 +271,7 @@ extern gboolean autogroup;
 
 #define UNGROUPED_DIVE(_dive) ((_dive)->tripflag == NO_TRIP)
 #define DIVE_IN_TRIP(_dive) ((_dive)->tripflag == IN_TRIP)
+#define DIVE_NEEDS_TRIP(_dive) ((_dive)->tripflag == TF_NONE)
 #define NEXT_TRIP(_entry) ((_entry) ? g_list_next(_entry) : (dive_trip_list))
 #define PREV_TRIP(_entry) ((_entry) ? g_list_previous(_entry) : g_list_last(dive_trip_list))
 #define DIVE_TRIP(_trip) ((struct dive *)(_trip)->data)

divelist.c

@@ -65,6 +65,9 @@ enum {
 	DIVELIST_COLUMNS
 };
 
+static void turn_dive_into_trip(GtkTreePath *path);
+static void merge_dive_into_trip_above_cb(GtkWidget *menuitem, GtkTreePath *path);
+
 #ifdef DEBUG_MODEL
 static gboolean dump_model_entry(GtkTreeModel *model, GtkTreePath *path,
 				GtkTreeIter *iter, gpointer data)
@@ -136,6 +139,28 @@ static void first_leaf(GtkTreeModel *model, GtkTreeIter *iter, int *diveidx)
 	}
 }
 
+static GtkTreePath *path_match;
+
+static gboolean match_dive(GtkTreeModel *model, GtkTreePath *path, GtkTreeIter *iter, gpointer data)
+{
+	int idx;
+	struct dive *dive = data;
+
+	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, -1);
+	if (idx >= 0)
+		if (get_dive(idx)->when == dive->when) {
+			path_match = gtk_tree_path_copy(path);
+			return TRUE;
+		}
+	return FALSE;
+}
+
+static GtkTreePath *get_path_from(struct dive *dive)
+{
+	gtk_tree_model_foreach(TREEMODEL(dive_list), match_dive, dive);
+	return path_match;
+}
+
 /* make sure that if we expand a summary row that is selected, the children show
    up as selected, too */
 void row_expanded_cb(GtkTreeView *tree_view, GtkTreeIter *iter, GtkTreePath *path, gpointer data)
@@ -935,6 +960,7 @@ static void fill_dive_list(void)
 	struct dive *last_trip = NULL;
 	GList *trip;
 	struct dive *dive_trip = NULL;
+	gboolean need_scan = FALSE;
 
 	/* if we have pre-existing trips, start on the last one */
 	trip = g_list_last(dive_trip_list);
@@ -981,6 +1007,15 @@ static void fill_dive_list(void)
 			dive_trip = NULL;
 			parent_ptr = NULL;
 		}
+		/* if we have an new dive and the dive_trip date is earlier than the
+		 * dive then this is an existing trip and a new dive; as we are walking the
+		 * dive_list oldest first it's very hard right now to know if this dive
+		 * should be in that trip; so postpone this decision until the 'forward'
+		 * scan at the end of this function */
+		if (DIVE_NEEDS_TRIP(dive) && dive_trip && dive_trip->when < dive->when) {
+			dive_trip = NULL;
+			need_scan = TRUE;
+		}
 		/* update dive as part of dive_trip and
 		 * (if necessary) update dive_trip time and location */
 		if (dive_trip) {
@@ -1041,6 +1076,43 @@ static void fill_dive_list(void)
 				DIVE_DATE, dive_trip->when,
 				DIVE_LOCATION, dive_trip->location,
 				-1);
+	/* now walk the dive list one more time to make sure any new
+	 * dives that fit into an existing dive_trip have been added
+	 * to the matching trips */
+	if (autogroup && need_scan) {
+		struct dive *dive;
+		time_t last_trip_dive_when;
+		GtkTreePath *path;
+
+		trip = dive_trip_list;
+		last_trip_dive_when = DIVE_TRIP(trip)->when;
+		for (i = 0; i < dive_table.nr; i++) {
+			dive = get_dive(i);
+			if (UNGROUPED_DIVE(dive)) {
+				/* this ends any trip */
+				trip = NULL;
+				last_trip_dive_when = 0;
+			} else if (DIVE_IN_TRIP(dive)) {
+				trip = find_matching_trip(dive->when);
+				if (dive->when > last_trip_dive_when)
+					last_trip_dive_when = dive->when;
+			} else { /* DIVE_NEEDS_TRIP */
+				if (dive->when - last_trip_dive_when < TRIP_THRESHOLD) {
+					/* dive should be in this trip */
+					dive->tripflag = IN_TRIP;
+					dive->divetrip = DIVE_TRIP(trip);
+					/* now move the tree node into place */
+					path = get_path_from(dive);
+					merge_dive_into_trip_above_cb(NULL, path);
+
+				} else {
+					/* we did need a new trip for this dive */
+					path = get_path_from(dive);
+					turn_dive_into_trip(path);
+				}
+			}
+		}
+	}
 	update_dive_list_units();
 	if (gtk_tree_model_get_iter_first(MODEL(dive_list), &iter)) {
 		GtkTreeSelection *selection;