Partial rewrite of the dive trip code

This introduces a new data structure for dive trips - reuseing the struct
dive just got way too messy.

The dive_trip_t datastructure now allows the code to remember if the trip
was auto generated or if its time stamp changed when dives where added to
the trip during auto generation.

The algorithm also distinguishes between dives that were intentionally
added to a trip (either in an XML file or by adding them to trip in the
UI) and dives that were added to trips via autogen. Saving dives that were
added to trips via autogen makes that assignment "intentional".

With this partial rewrite several of the oddities of the old code should
be resolved - especially turning autogen on and off again should get the
divelist back to the previous stage.

Also, when dives are merged during file open or import we now try to pick
the correct tripflag (instead of just ignoring the tripflag completely and
resetting it to TF_NONE by mistake).

Finally, the dive trip debugging code got more verbose and is trying
harder to detect issues at the earliest time possible.

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

5 files changed, 136 insertions, 50 deletions

diff --git a/dive.c b/dive.c
index 52ec64517..b1739ad80 100644
--- a/dive.c
+++ b/dive.c
@@ -710,6 +710,11 @@ struct dive *try_to_merge(struct dive *a, struct dive *b)
 	res = alloc_dive();
 
 	res->when = a->when;
+	/* the larger tripflag is more relevant */
+	if(a->tripflag > b->tripflag)
+		res->tripflag = a->tripflag;
+	else
+		res->tripflag = b->tripflag;
 	MERGE_NONZERO(res, a, b, latitude);
 	MERGE_NONZERO(res, a, b, longitude);
 	MERGE_TXT(res, a, b, location);
diff --git a/dive.h b/dive.h
index e443ce965..c326de1ea 100644
--- a/dive.h
+++ b/dive.h
@@ -236,13 +236,21 @@ struct event {
 #define W_IDX_PRIMARY 0
 #define W_IDX_SECONDARY 1
 
-typedef enum { TF_NONE, NO_TRIP, IN_TRIP, NUM_TRIPFLAGS } tripflag_t;
+typedef enum { TF_NONE, NO_TRIP, IN_TRIP, ASSIGNED_TRIP, AUTOGEN_TRIP, NUM_TRIPFLAGS } tripflag_t;
 extern const char *tripflag_names[NUM_TRIPFLAGS];
 
+typedef struct dive_trip {
+	tripflag_t tripflag;
+	time_t when;
+	time_t when_from_file;
+	char *location;
+	char *notes;
+} dive_trip_t;
+
 struct dive {
 	int number;
 	tripflag_t tripflag;
-	struct dive *divetrip;
+	dive_trip_t *divetrip;
 	int selected;
 	time_t when;
 	char *location;
@@ -275,21 +283,21 @@ extern gboolean autogroup;
 #define TRIP_THRESHOLD 3600*24*3
 
 #define UNGROUPED_DIVE(_dive) ((_dive)->tripflag == NO_TRIP)
-#define DIVE_IN_TRIP(_dive) ((_dive)->tripflag == IN_TRIP)
+#define DIVE_IN_TRIP(_dive) ((_dive)->tripflag == IN_TRIP || (_dive)->tripflag == ASSIGNED_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)
+#define DIVE_TRIP(_trip) ((dive_trip_t *)(_trip)->data)
 #define DIVE_FITS_TRIP(_dive, _dive_trip) ((_dive_trip)->when - TRIP_THRESHOLD <= (_dive)->when)
 
 /* compare two dives by when they happened */
 static inline int dive_date_cmp(gconstpointer _a, gconstpointer _b) {
-	return ((struct dive *)_a)->when - ((struct dive *)_b)->when;
+	return ((dive_trip_t *)_a)->when - ((dive_trip_t *)_b)->when;
 }
 
 /* returns 0 if the dive happened exactly at time */
-static inline int dive_when_find(gconstpointer _dive, gconstpointer _time) {
-	return ((struct dive *)_dive)->when != (time_t) _time;
+static inline int dive_when_find(gconstpointer _dive_trip, gconstpointer _time) {
+	return ((dive_trip_t *)_dive_trip)->when != (time_t) _time;
 }
 
 #define FIND_TRIP(_when) g_list_find_custom(dive_trip_list, (gconstpointer)(_when), dive_when_find)
@@ -299,10 +307,22 @@ static void dump_trip_list(void)
 {
 	GList *p = NULL;
 	int i=0;
+	time_t last_time = 0;
 	while ((p = NEXT_TRIP(p))) {
-		struct tm *tm = gmtime(&DIVE_TRIP(p)->when);
-		printf("trip %d to \"%s\" on %04u-%02u-%02u %02u:%02u:%02u\n", ++i, DIVE_TRIP(p)->location,
+		dive_trip_t *dive_trip = DIVE_TRIP(p);
+		struct tm *tm = gmtime(&dive_trip->when);
+		if (dive_trip->when < last_time)
+			printf("\n\ndive_trip_list OUT OF ORDER!!!\n\n\n");
+		printf("%s trip %d to \"%s\" on %04u-%02u-%02u %02u:%02u:%02u\n",
+			dive_trip->tripflag == AUTOGEN_TRIP ? "autogen " : "",
+			++i, dive_trip->location,
 			tm->tm_year + 1900, tm->tm_mon+1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
+		if (dive_trip->when_from_file && dive_trip->when != dive_trip->when_from_file) {
+			tm = gmtime(&dive_trip->when_from_file);
+			printf("originally on %04u-%02u-%02u %02u:%02u:%02u\n",	tm->tm_year + 1900,
+				tm->tm_mon+1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
+		}
+		last_time = dive_trip->when;
 	}
 	printf("-----\n");
 }
@@ -311,9 +331,9 @@ static void dump_trip_list(void)
 /* insert the trip into the dive_trip_list - but ensure you don't have
  * two trips for the same date; but if you have, make sure you don't
  * keep the one with less information */
-static void inline insert_trip(struct dive **trip)
+static void inline insert_trip(dive_trip_t **trip)
 {
-	struct dive *dive_trip = *trip;
+	dive_trip_t *dive_trip = *trip;
 	GList *result = FIND_TRIP(dive_trip->when);
 	if (result) {
 		if (! DIVE_TRIP(result)->location)
@@ -447,7 +467,7 @@ extern void remember_event(const char *eventname);
 extern void evn_foreach(void (*callback)(const char *, int *, void *), void *data);
 
 extern int add_new_dive(struct dive *dive);
-extern gboolean edit_trip(struct dive *trip);
+extern gboolean edit_trip(dive_trip_t *trip);
 extern int edit_dive_info(struct dive *dive);
 extern int edit_multi_dive_info(struct dive *single_dive);
 extern void dive_list_update_dives(void);
diff --git a/divelist.c b/divelist.c
index 909e27bea..3c826c3d6 100644
--- a/divelist.c
+++ b/divelist.c
@@ -41,7 +41,10 @@ static struct DiveList dive_list;
 GList *dive_trip_list;
 gboolean autogroup = FALSE;
 
-const char *tripflag_names[NUM_TRIPFLAGS] = { "TF_NONE", "NOTRIP", "INTRIP" };
+/* this duplicate assignment of "INTRIP" causes the save_xml code
+ * to convert an ASSIGNED_TRIP (which is temporary in memory) to
+ * a statically assigned trip (INTRIP) in file */
+const char *tripflag_names[NUM_TRIPFLAGS] = { "TF_NONE", "NOTRIP", "INTRIP", "INTRIP", "AUTOGEN_TRIP" };
 
 /*
  * The dive list has the dive data in both string format (for showing)
@@ -947,16 +950,29 @@ void update_dive_list_col_visibility(void)
 static GList *find_matching_trip(time_t when)
 {
 	GList *trip = dive_trip_list;
-	if (!trip || DIVE_TRIP(trip)->when > when)
+	if (!trip || DIVE_TRIP(trip)->when > when) {
+#ifdef DEBUG_TRIP
+		printf("before first trip\n");
+#endif
 		return NULL;
+	}
 	while (trip->next && DIVE_TRIP(trip->next)->when <= when)
 		trip = trip->next;
+#ifdef DEBUG_TRIP
+	{
+		struct tm *tm;
+		tm = gmtime(&DIVE_TRIP(trip)->when);
+		printf("found trip @ %04d-%02d-%02d %02d:%02d:%02d\n",
+			tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday,
+			tm->tm_hour, tm->tm_min, tm->tm_sec);
+	}
+#endif
 	return trip;
 }
 
-static struct dive *create_and_hookup_trip_from_dive(struct dive *dive)
+static dive_trip_t *create_and_hookup_trip_from_dive(struct dive *dive)
 {
-	struct dive *dive_trip = alloc_dive();
+	dive_trip_t *dive_trip = calloc(sizeof(dive_trip_t),1);
 	dive_trip->when = dive->when;
 	if (dive->location)
 		dive_trip->location = strdup(dive->location);
@@ -973,7 +989,7 @@ static struct dive *create_and_hookup_trip_from_dive(struct dive *dive)
  * that starts at when and check on the way that there is no ungrouped
  * dive and no break beyond the 3 day threshold between dives that
  * haven't already been assigned to this trip */
-static gboolean dive_can_be_in_trip(int idx, struct dive *dive_trip)
+static gboolean dive_can_be_in_trip(int idx, dive_trip_t *dive_trip)
 {
 	struct dive *dive, *pdive;
 	int i = idx;
@@ -1014,9 +1030,9 @@ static void fill_dive_list(void)
 	int i;
 	GtkTreeIter iter, parent_iter, *parent_ptr = NULL;
 	GtkTreeStore *liststore, *treestore;
-	struct dive *last_trip = NULL;
+	dive_trip_t *last_trip = NULL;
 	GList *trip;
-	struct dive *dive_trip = NULL;
+	dive_trip_t *dive_trip = NULL;
 
 	/* if we have pre-existing trips, start on the last one */
 	trip = g_list_last(dive_trip_list);
@@ -1049,26 +1065,42 @@ static void fill_dive_list(void)
 			dive_trip = NULL;
 		} else if (autogroup && DIVE_NEEDS_TRIP(dive)){
 			/* if we already have existing trips there are up to two trips that this
-			 * could potentially be part of. Let's try the one we are on, first */
-			if (! (dive_trip && dive_can_be_in_trip(i, dive_trip))) {
-				/* there could be a better trip in our list already */
-				trip = find_matching_trip(dive->when);
-				if (! (trip && dive_can_be_in_trip(i, DIVE_TRIP(trip)))) {
+			 * could potentially be part of.
+			 * Let's see if there is a matching one already */
+			GList *matching_trip;
+			matching_trip = find_matching_trip(dive->when);
+			if (matching_trip && dive_can_be_in_trip(i, DIVE_TRIP(matching_trip))) {
+				trip = matching_trip;
+			} else {
+				/* is there a trip we can extend ? */
+				if (! matching_trip && dive_trip) {
+					/* careful - this is before the first trip
+					   yet we have a trip we're looking at; make
+					   sure that is indeed the first trip */
+					dive_trip = DIVE_TRIP(dive_trip_list);
+					trip = dive_trip_list;
+				}
+				/* maybe we can extend the current trip */
+				if (! (dive_trip && dive_can_be_in_trip(i, dive_trip))) {
 					/* seems like neither of these trips work, so create
 					 * a new one; all fields default to 0 and get filled
 					 * in further down */
 					parent_ptr = NULL;
 					dive_trip = create_and_hookup_trip_from_dive(dive);
-					dive_trip->tripflag = IN_TRIP;
+					dive_trip->tripflag = AUTOGEN_TRIP;
 					trip = FIND_TRIP(dive_trip->when);
 				}
-				if (trip)
-					dive_trip = DIVE_TRIP(trip);
 			}
+			if (trip)
+				dive_trip = DIVE_TRIP(trip);
 		} else if (DIVE_IN_TRIP(dive)) {
 			trip = find_matching_trip(dive->when);
 			if (trip)
 				dive_trip = DIVE_TRIP(trip);
+			else
+				printf ("data seems inconsistent - dive claims to be in dive trip "
+					"yet there appears to be no matching trip\n"
+					"Trying to recover\n");
 		} else {
 			/* dive is not in a trip and we aren't autogrouping */
 			dive_trip = NULL;
@@ -1077,7 +1109,8 @@ static void fill_dive_list(void)
 		/* update dive as part of dive_trip and
 		 * (if necessary) update dive_trip time and location */
 		if (dive_trip) {
-			dive->tripflag = IN_TRIP;
+			if(DIVE_NEEDS_TRIP(dive))
+				dive->tripflag = ASSIGNED_TRIP;
 			dive->divetrip = dive_trip;
 			if (dive_trip->when > dive->when)
 				dive_trip->when = dive->when;
@@ -1126,6 +1159,9 @@ static void fill_dive_list(void)
 			DIVE_SUIT, dive->suit,
 			DIVE_SAC, 0,
 			-1);
+#ifdef DEBUG_TRIP
+		dump_trip_list();
+#endif
 	}
 
 	/* make sure we display the first date of the trip in previous summary */
@@ -1263,7 +1299,7 @@ void edit_trip_cb(GtkWidget *menuitem, GtkTreePath *path)
 {
 	GtkTreeIter iter;
 	time_t when;
-	struct dive *dive_trip;
+	dive_trip_t *dive_trip;
 	GList *trip;
 
 	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
@@ -1339,7 +1375,7 @@ static int copy_tree_node(GtkTreeIter *a, GtkTreeIter *b)
 /* to avoid complicated special cases based on ordering or number of children,
    we always take the first and last child and pick the smaller time_t (which
    works regardless of ordering and also with just one child) */
-static void update_trip_timestamp(GtkTreeIter *parent, struct dive *divetrip)
+static void update_trip_timestamp(GtkTreeIter *parent, dive_trip_t *divetrip)
 {
 	GtkTreeIter first_child, last_child;
 	int nr;
@@ -1369,7 +1405,8 @@ static GtkTreeIter *move_dive_between_trips(GtkTreeIter *dive_iter, GtkTreeIter
 {
 	int idx;
 	time_t old_when, new_when;
-	struct dive *dive, *old_divetrip, *new_divetrip;
+	struct dive *dive;
+	dive_trip_t *old_divetrip, *new_divetrip;
 	GtkTreeIter *new_iter = malloc(sizeof(GtkTreeIter));
 
 	if (before)
@@ -1447,6 +1484,7 @@ static void turn_dive_into_trip(GtkTreePath *path)
 	char *location;
 	int idx;
 	struct dive *dive;
+	dive_trip_t *dive_trip;
 
 	/* this is a dive on the top level, insert trip AFTER it, populate its date / location, and
 	 * then move the dive below that trip */
@@ -1461,8 +1499,10 @@ static void turn_dive_into_trip(GtkTreePath *path)
 	treepath = gtk_tree_model_get_path(MODEL(dive_list), newiter);
 	gtk_tree_view_expand_to_path(GTK_TREE_VIEW(dive_list.tree_view), treepath);
 	dive = get_dive(idx);
-	/* we don't need the return value - everything is hooked up in the function */
-	(void)create_and_hookup_trip_from_dive(dive);
+	/* this trip is intentionally created so it should be treated as if
+	 * it was read from a file */
+	dive_trip = create_and_hookup_trip_from_dive(dive);
+	dive_trip->when_from_file = dive_trip->when;
 }
 
 /* we know that path is pointing at a dive in a trip and are asked to split this trip into two */
@@ -1470,7 +1510,8 @@ static void insert_trip_before(GtkTreePath *path)
 {
 	GtkTreeIter iter, prev_iter, parent, newparent, nextsibling;
 	GtkTreePath *treepath, *prev_path;
-	struct dive *dive, *prev_dive, *new_divetrip;
+	struct dive *dive, *prev_dive;
+	dive_trip_t *new_divetrip;
 	int idx, nr, i;
 
 	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
@@ -1509,6 +1550,8 @@ static void insert_trip_before(GtkTreePath *path)
 			/* we copied the dive we were called with; we are done */
 			break;
 	}
+	/* treat this divetrip as if it had been read from a file */
+	new_divetrip->when_from_file = new_divetrip->when;
 	treepath = gtk_tree_model_get_path(MODEL(dive_list), &newparent);
 	gtk_tree_view_expand_to_path(GTK_TREE_VIEW(dive_list.tree_view), treepath);
 #ifdef DEBUG_TRIP
@@ -1642,7 +1685,8 @@ static void remove_from_trip_cb(GtkWidget *menuitem, GtkTreePath *path)
 void remove_trip(GtkTreePath *trippath, gboolean force_no_trip)
 {
 	GtkTreeIter newiter, parent, child, *lastiter = &parent;
-	struct dive *dive, *dive_trip = NULL;
+	struct dive *dive;
+	dive_trip_t *dive_trip = NULL;
 	int idx;
 	GtkTreePath *childpath;
 	GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));
@@ -2101,11 +2145,25 @@ void remove_autogen_trips()
 		gtk_tree_model_get(TREEMODEL(dive_list), &iter, DIVE_INDEX, &idx, DIVE_DATE, &when, -1);
 		if (idx < 0) {
 			trip = FIND_TRIP(when);
-			if (DIVE_TRIP(trip)->tripflag == IN_TRIP) { /* this was autogen */
+			if (trip && DIVE_TRIP(trip)->tripflag == AUTOGEN_TRIP) { /* this was autogen */
 				remove_trip(path, FALSE);
 				continue;
 			}
 		}
 		gtk_tree_path_next(path);
 	}
+	/* now walk the remaining trips in the dive_trip_list and restore
+	 * their original time stamp; we don't do this in the loop above
+	 * to ensure that the list stays in chronological order */
+	trip = NULL;
+	while(NEXT_TRIP(trip)) {
+		trip = NEXT_TRIP(trip);
+		DIVE_TRIP(trip)->when = DIVE_TRIP(trip)->when_from_file;
+	}
+	/* finally walk the dives and remove the 'ASSIGNED_TRIP' designator */
+	for (idx = 0; idx < dive_table.nr; idx++) {
+		struct dive *dive = get_dive(idx);
+		if (dive->tripflag == ASSIGNED_TRIP)
+			dive->tripflag = TF_NONE;
+	}
 }
diff --git a/info.c b/info.c
index ad482f11d..87e34f142 100644
--- a/info.c
+++ b/info.c
@@ -443,7 +443,7 @@ static void save_dive_info_changes(struct dive *dive, struct dive *master, struc
 	}
 }
 
-static void dive_trip_widget(GtkWidget *box, struct dive *trip, struct dive_info *info)
+static void dive_trip_widget(GtkWidget *box, dive_trip_t *trip, struct dive_info *info)
 {
 	GtkWidget *hbox, *label;
 	char buffer[80] = "Edit trip summary";
@@ -535,7 +535,7 @@ void update_equipment_data(struct dive *dive, struct dive *master)
 		memcpy(dive->weightsystem, master->weightsystem, WS_BYTES);
 }
 
-gboolean edit_trip(struct dive *trip)
+gboolean edit_trip(dive_trip_t *trip)
 {
 	GtkWidget *dialog, *vbox;
 	int success;
@@ -569,10 +569,8 @@ gboolean edit_trip(struct dive *trip)
 			if (old_text)
 				g_free(old_text);
 		}
-		if (changed) {
+		if (changed)
 			mark_divelist_changed(TRUE);
-			flush_divelist(trip);
-		}
 	}
 	gtk_widget_destroy(dialog);
 	return changed;
diff --git a/parse-xml.c b/parse-xml.c
index 2a10792f8..4950d5d96 100644
--- a/parse-xml.c
+++ b/parse-xml.c
@@ -156,7 +156,8 @@ const struct units IMPERIAL_units = {
 /*
  * Dive info as it is being built up..
  */
-static struct dive *cur_dive, *cur_trip = NULL;
+static struct dive *cur_dive;
+static dive_trip_t *cur_trip = NULL;
 static struct sample *cur_sample;
 static struct {
 	int active;
@@ -542,8 +543,10 @@ static void get_tripflag(char *buffer, void *_tf)
 
 	*tf = TF_NONE;
 	for (i = NO_TRIP; i < NUM_TRIPFLAGS; i++)
-		if(! strcmp(buffer, tripflag_names[i]))
+		if(! strcmp(buffer, tripflag_names[i])) {
 			*tf = i;
+			break;
+		}
 }
 
 static void centibar(char *buffer, void *_pressure)
@@ -1152,21 +1155,23 @@ static void try_to_fill_dive(struct dive **divep, const char *name, char *buf)
 }
 
 /* We're in the top-level trip xml. Try to convert whatever value to a trip value */
-static void try_to_fill_trip(struct dive **divep, const char *name, char *buf)
+static void try_to_fill_trip(dive_trip_t **dive_trip_p, const char *name, char *buf)
 {
 	int len = strlen(name);
 
 	start_match("trip", name, buf);
 
-	struct dive *dive = *divep;
+	dive_trip_t *dive_trip = *dive_trip_p;
 
-	if (MATCH(".date", divedate, &dive->when))
+	if (MATCH(".date", divedate, &dive_trip->when))
 		return;
-	if (MATCH(".time", divetime, &dive->when))
+	if (MATCH(".time", divetime, &dive_trip->when)) {
+		dive_trip->when_from_file = dive_trip->when;
 		return;
-	if (MATCH(".location", utf8_string, &dive->location))
+	}
+	if (MATCH(".location", utf8_string, &dive_trip->location))
 		return;
-	if (MATCH(".notes", utf8_string, &dive->notes))
+	if (MATCH(".notes", utf8_string, &dive_trip->notes))
 		return;
 
 	nonmatch("trip", name, buf);
@@ -1212,7 +1217,7 @@ static void trip_start(void)
 {
 	if (cur_trip)
 		return;
-	cur_trip = alloc_dive();
+	cur_trip = calloc(sizeof(dive_trip_t),1);
 	memset(&cur_tm, 0, sizeof(cur_tm));
 }