subsurface/divelist.c

/* divelist.c */
/* this creates the UI for the dive list -
 * controlled through the following interfaces:
 *
 * void flush_divelist(struct dive *dive)
 * GtkWidget dive_list_create(void)
 * void dive_list_update_dives(void)
 * void update_dive_list_units(void)
 * void set_divelist_font(const char *font)
 * void mark_divelist_changed(int changed)
 * int unsaved_changes()
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <math.h>

#include "divelist.h"
#include "dive.h"
#include "display.h"
#include "display-gtk.h"

struct DiveList {
	GtkWidget    *tree_view;
	GtkWidget    *container_widget;
	GtkTreeStore *model, *listmodel, *treemodel;
	GtkTreeViewColumn *nr, *date, *stars, *depth, *duration, *location;
	GtkTreeViewColumn *temperature, *cylinder, *totalweight, *suit, *nitrox, *sac, *otu;
	int changed;
};

static struct DiveList dive_list;
#define MODEL(_dl) GTK_TREE_MODEL((_dl).model)
#define TREEMODEL(_dl) GTK_TREE_MODEL((_dl).treemodel)
#define LISTMODEL(_dl) GTK_TREE_MODEL((_dl).listmodel)
#define STORE(_dl) GTK_TREE_STORE((_dl).model)
#define TREESTORE(_dl) GTK_TREE_STORE((_dl).treemodel)
#define LISTSTORE(_dl) GTK_TREE_STORE((_dl).listmodel)

GList *dive_trip_list;
gboolean autogroup = FALSE;

/* 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)
 * and in "raw" format (for sorting purposes)
 */
enum {
	DIVE_INDEX = 0,
	DIVE_NR,		/* int: dive->nr */
	DIVE_DATE,		/* timestamp_t: dive->when */
	DIVE_RATING,		/* int: 0-5 stars */
	DIVE_DEPTH,		/* int: dive->maxdepth in mm */
	DIVE_DURATION,		/* int: in seconds */
	DIVE_TEMPERATURE,	/* int: in mkelvin */
	DIVE_TOTALWEIGHT,	/* int: in grams */
	DIVE_SUIT,		/* "wet, 3mm" */
	DIVE_CYLINDER,
	DIVE_NITROX,		/* int: dummy */
	DIVE_SAC,		/* int: in ml/min */
	DIVE_OTU,		/* int: in OTUs */
	DIVE_LOCATION,		/* "2nd Cathedral, Lanai" */
	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)
{
	char *location;
	int idx, nr, duration;
	struct dive *dive;
	timestamp_t when;
	struct tm tm;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_NR, &nr, DIVE_DATE, &when,
			DIVE_DURATION, &duration, DIVE_LOCATION, &location, -1);
	utc_mkdate(when, &tm);
	printf("iter %x:%x entry #%d : nr %d @ %04d-%02d-%02d %02d:%02d:%02d duration %d location %s ",
		iter->stamp, iter->user_data, idx, nr,
		tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday,
		tm.tm_hour, tm.tm_min, tm.tm_sec,
		duration, location);
	dive = get_dive(idx);
	if (dive)
		printf("tripflag %d\n", dive->tripflag);
	else
		printf("without matching dive\n");

	free(location);

	return FALSE;
}

static void dump_model(GtkListStore *store)
{
	gtk_tree_model_foreach(GTK_TREE_MODEL(store), dump_model_entry, NULL);
	printf("\n---\n\n");
}
#endif

#if DEBUG_SELECTION_TRACKING
void dump_selection(void)
{
	int i;
	struct dive *dive;

	printf("currently selected are %u dives:", amount_selected);
	for_each_dive(i, dive) {
		if (dive->selected)
			printf(" %d", i);
	}
	printf("\n");
}
#endif

/* when subsurface starts we want to have the last dive selected. So we simply
   walk to the first leaf (and skip the summary entries - which have negative
   DIVE_INDEX) */
static void first_leaf(GtkTreeModel *model, GtkTreeIter *iter, int *diveidx)
{
	GtkTreeIter parent;
	GtkTreePath *tpath;

	while (*diveidx < 0) {
		memcpy(&parent, iter, sizeof(parent));
		tpath = gtk_tree_model_get_path(model, &parent);
		if (!gtk_tree_model_iter_children(model, iter, &parent))
			/* we should never have a parent without child */
			return;
		if(!gtk_tree_view_row_expanded(GTK_TREE_VIEW(dive_list.tree_view), tpath))
			gtk_tree_view_expand_row(GTK_TREE_VIEW(dive_list.tree_view), tpath, FALSE);
		gtk_tree_model_get(model, iter, DIVE_INDEX, diveidx, -1);
	}
}

static struct dive *dive_from_path(GtkTreePath *path)
{
	GtkTreeIter iter;
	int idx;

	if (gtk_tree_model_get_iter(MODEL(dive_list), &iter, path)) {
		gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &idx, -1);
		return get_dive(idx);
	} else {
		return NULL;
	}

}

/* 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)
{
	GtkTreeIter child;
	GtkTreeModel *model = MODEL(dive_list);
	GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));

	if (!gtk_tree_model_iter_children(model, &child, iter))
		return;

	do {
		int idx;
		struct dive *dive;

		gtk_tree_model_get(model, &child, DIVE_INDEX, &idx, -1);
		dive = get_dive(idx);

		if (dive->selected)
			gtk_tree_selection_select_iter(selection, &child);
		else
			gtk_tree_selection_unselect_iter(selection, &child);
	} while (gtk_tree_model_iter_next(model, &child));
}

static int selected_children(GtkTreeModel *model, GtkTreeIter *iter)
{
	GtkTreeIter child;

	if (!gtk_tree_model_iter_children(model, &child, iter))
		return FALSE;

	do {
		int idx;
		struct dive *dive;

		gtk_tree_model_get(model, &child, DIVE_INDEX, &idx, -1);
		dive = get_dive(idx);

		if (dive->selected)
			return TRUE;
	} while (gtk_tree_model_iter_next(model, &child));
	return FALSE;
}

/* Make sure that if we collapse a summary row with any selected children, the row
   shows up as selected too */
void row_collapsed_cb(GtkTreeView *tree_view, GtkTreeIter *iter, GtkTreePath *path, gpointer data)
{
	GtkTreeModel *model = MODEL(dive_list);
	GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));

	if (selected_children(model, iter))
		gtk_tree_selection_select_iter(selection, iter);
}

static GList *selection_changed = NULL;

/*
 * This is called _before_ the selection is changed, for every single entry;
 *
 * We simply create a list of all changed entries, and make sure that the
 * group entries go at the end of the list.
 */
gboolean modify_selection_cb(GtkTreeSelection *selection, GtkTreeModel *model,
			GtkTreePath *path, gboolean was_selected, gpointer userdata)
{
	GtkTreeIter iter, *p;

	if (!gtk_tree_model_get_iter(model, &iter, path))
		return TRUE;

	/* Add the group entries to the end */
	p = gtk_tree_iter_copy(&iter);
	if (gtk_tree_model_iter_has_child(model, p))
		selection_changed = g_list_append(selection_changed, p);
	else
		selection_changed = g_list_prepend(selection_changed, p);
	return TRUE;
}

static void select_dive(struct dive *dive, int selected)
{
	if (dive->selected != selected) {
		amount_selected += selected ? 1 : -1;
		dive->selected = selected;
	}
}

/*
 * This gets called when a dive group has changed selection.
 */
static void select_dive_group(GtkTreeModel *model, GtkTreeSelection *selection, GtkTreeIter *iter, int selected)
{
	int first = 1;
	GtkTreeIter child;

	if (selected == selected_children(model, iter))
		return;

	if (!gtk_tree_model_iter_children(model, &child, iter))
		return;

	do {
		int idx;
		struct dive *dive;

		gtk_tree_model_get(model, &child, DIVE_INDEX, &idx, -1);
		if (first && selected)
			selected_dive = idx;
		first = 0;
		dive = get_dive(idx);
		if (dive->selected == selected)
			continue;

		select_dive(dive, selected);
		if (selected)
			gtk_tree_selection_select_iter(selection, &child);
		else
			gtk_tree_selection_unselect_iter(selection, &child);
	} while (gtk_tree_model_iter_next(model, &child));
}

/*
 * This gets called _after_ the selections have changed, for each entry that
 * may have changed. Check if the gtk selection state matches our internal
 * selection state to verify.
 *
 * The group entries are at the end, this guarantees that we have handled
 * all the dives before we handle groups.
 */
static void check_selection_cb(GtkTreeIter *iter, GtkTreeSelection *selection)
{
	GtkTreeModel *model = MODEL(dive_list);
	struct dive *dive;
	int idx, gtk_selected;

	gtk_tree_model_get(model, iter,
		DIVE_INDEX, &idx,
		-1);
	dive = get_dive(idx);
	gtk_selected = gtk_tree_selection_iter_is_selected(selection, iter);
	if (idx < 0)
		select_dive_group(model, selection, iter, gtk_selected);
	else {
		select_dive(dive, gtk_selected);
		if (gtk_selected)
			selected_dive = idx;
	}
	gtk_tree_iter_free(iter);
}

/* this is called when gtk thinks that the selection has changed */
static void selection_cb(GtkTreeSelection *selection, GtkTreeModel *model)
{
	GList *changed = selection_changed;

	selection_changed = NULL;
	g_list_foreach(changed, (GFunc) check_selection_cb, selection);
	g_list_free(changed);
#if DEBUG_SELECTION_TRACKING
	dump_selection();
#endif

	process_selected_dives();
	repaint_dive();
}

const char *star_strings[] = {
	ZERO_STARS,
	ONE_STARS,
	TWO_STARS,
	THREE_STARS,
	FOUR_STARS,
	FIVE_STARS
};

static void star_data_func(GtkTreeViewColumn *col,
			   GtkCellRenderer *renderer,
			   GtkTreeModel *model,
			   GtkTreeIter *iter,
			   gpointer data)
{
	int nr_stars, idx;
	char buffer[40];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_RATING, &nr_stars, -1);
	if (idx < 0) {
		*buffer = '\0';
	} else {
		if (nr_stars < 0 || nr_stars > 5)
			nr_stars = 0;
		snprintf(buffer, sizeof(buffer), "%s", star_strings[nr_stars]);
	}
	g_object_set(renderer, "text", buffer, NULL);
}

static void date_data_func(GtkTreeViewColumn *col,
			   GtkCellRenderer *renderer,
			   GtkTreeModel *model,
			   GtkTreeIter *iter,
			   gpointer data)
{
	int idx, nr;
	struct tm tm;
	timestamp_t when;
	char buffer[40];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_DATE, &when, -1);
	nr = gtk_tree_model_iter_n_children(model, iter);

	utc_mkdate(when, &tm);
	if (idx < 0) {
		snprintf(buffer, sizeof(buffer),
			"Trip %s, %s %d, %d (%d dive%s)",
			weekday(tm.tm_wday),
			monthname(tm.tm_mon),
			tm.tm_mday, tm.tm_year + 1900,
			nr, nr > 1 ? "s" : "");
	} else {
		snprintf(buffer, sizeof(buffer),
			"%s, %s %d, %d %02d:%02d",
			weekday(tm.tm_wday),
			monthname(tm.tm_mon),
			tm.tm_mday, tm.tm_year + 1900,
			tm.tm_hour, tm.tm_min);
	}
	g_object_set(renderer, "text", buffer, NULL);
}

static void depth_data_func(GtkTreeViewColumn *col,
			    GtkCellRenderer *renderer,
			    GtkTreeModel *model,
			    GtkTreeIter *iter,
			    gpointer data)
{
	int depth, integer, frac, len, idx;
	char buffer[40];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_DEPTH, &depth, -1);

	if (idx < 0) {
		*buffer = '\0';
	} else {
		switch (output_units.length) {
		case METERS:
			/* To tenths of meters */
			depth = (depth + 49) / 100;
			integer = depth / 10;
			frac = depth % 10;
			if (integer < 20)
				break;
			if (frac >= 5)
				integer++;
			frac = -1;
			break;
		case FEET:
			integer = mm_to_feet(depth) + 0.5;
			frac = -1;
			break;
		default:
			return;
		}
		len = snprintf(buffer, sizeof(buffer), "%d", integer);
		if (frac >= 0)
			len += snprintf(buffer+len, sizeof(buffer)-len, ".%d", frac);
	}
	g_object_set(renderer, "text", buffer, NULL);
}

static void duration_data_func(GtkTreeViewColumn *col,
			       GtkCellRenderer *renderer,
			       GtkTreeModel *model,
			       GtkTreeIter *iter,
			       gpointer data)
{
	unsigned int sec;
	int idx;
	char buffer[16];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_DURATION, &sec, -1);
	if (idx < 0)
		*buffer = '\0';
	else
		snprintf(buffer, sizeof(buffer), "%d:%02d", sec / 60, sec % 60);

	g_object_set(renderer, "text", buffer, NULL);
}

static void temperature_data_func(GtkTreeViewColumn *col,
				  GtkCellRenderer *renderer,
				  GtkTreeModel *model,
				  GtkTreeIter *iter,
				  gpointer data)
{
	int value, idx;
	char buffer[80];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_TEMPERATURE, &value, -1);

	*buffer = 0;
	if (idx >= 0 && value) {
		double deg;
		switch (output_units.temperature) {
		case CELSIUS:
			deg = mkelvin_to_C(value);
			break;
		case FAHRENHEIT:
			deg = mkelvin_to_F(value);
			break;
		default:
			return;
		}
		snprintf(buffer, sizeof(buffer), "%.1f", deg);
	}

	g_object_set(renderer, "text", buffer, NULL);
}

static void nr_data_func(GtkTreeViewColumn *col,
			   GtkCellRenderer *renderer,
			   GtkTreeModel *model,
			   GtkTreeIter *iter,
			   gpointer data)
{
	int idx, nr;
	char buffer[40];
	struct dive *dive;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_NR, &nr, -1);
	if (idx < 0) {
		*buffer = '\0';
	} else {
		/* make dives that are not in trips stand out */
		dive = get_dive(idx);
		if (!DIVE_IN_TRIP(dive))
			snprintf(buffer, sizeof(buffer), "<b>%d</b>", nr);
		else
			snprintf(buffer, sizeof(buffer), "%d", nr);
	}
	g_object_set(renderer, "markup", buffer, NULL);
}

/*
 * Get "maximal" dive gas for a dive.
 * Rules:
 *  - Trimix trumps nitrox (highest He wins, O2 breaks ties)
 *  - Nitrox trumps air (even if hypoxic)
 * These are the same rules as the inter-dive sorting rules.
 */
static void get_dive_gas(struct dive *dive, int *o2_p, int *he_p, int *o2low_p)
{
	int i;
	int maxo2 = -1, maxhe = -1, mino2 = 1000;

	for (i = 0; i < MAX_CYLINDERS; i++) {
		cylinder_t *cyl = dive->cylinder + i;
		struct gasmix *mix = &cyl->gasmix;
		int o2 = mix->o2.permille;
		int he = mix->he.permille;

		if (cylinder_none(cyl))
			continue;
		if (!o2)
			o2 = AIR_PERMILLE;
		if (o2 < mino2)
			mino2 = o2;
		if (he > maxhe)
			goto newmax;
		if (he < maxhe)
			continue;
		if (o2 <= maxo2)
			continue;
newmax:
		maxhe = he;
		maxo2 = o2;
	}
	/* All air? Show/sort as "air"/zero */
	if (!maxhe && maxo2 == AIR_PERMILLE && mino2 == maxo2)
		maxo2 = mino2 = 0;
	*o2_p = maxo2;
	*he_p = maxhe;
	*o2low_p = mino2;
}

static int total_weight(struct dive *dive)
{
	int i, total_grams = 0;

	if (dive)
		for (i=0; i< MAX_WEIGHTSYSTEMS; i++)
			total_grams += dive->weightsystem[i].weight.grams;
	return total_grams;
}

static void weight_data_func(GtkTreeViewColumn *col,
			     GtkCellRenderer *renderer,
			     GtkTreeModel *model,
			     GtkTreeIter *iter,
			     gpointer data)
{
	int indx, decimals;
	double value;
	char buffer[80];
	struct dive *dive;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &indx, -1);
	dive = get_dive(indx);
	value = get_weight_units(total_weight(dive), &decimals, NULL);
	if (value == 0.0)
		*buffer = '\0';
	else
		snprintf(buffer, sizeof(buffer), "%.*f", decimals, value);

	g_object_set(renderer, "text", buffer, NULL);
}

static gint nitrox_sort_func(GtkTreeModel *model,
	GtkTreeIter *iter_a,
	GtkTreeIter *iter_b,
	gpointer user_data)
{
	int index_a, index_b;
	struct dive *a, *b;
	int a_o2, b_o2;
	int a_he, b_he;
	int a_o2low, b_o2low;

	gtk_tree_model_get(model, iter_a, DIVE_INDEX, &index_a, -1);
	gtk_tree_model_get(model, iter_b, DIVE_INDEX, &index_b, -1);
	a = get_dive(index_a);
	b = get_dive(index_b);
	get_dive_gas(a, &a_o2, &a_he, &a_o2low);
	get_dive_gas(b, &b_o2, &b_he, &b_o2low);

	/* Sort by Helium first, O2 second */
	if (a_he == b_he) {
		if (a_o2 == b_o2)
			return a_o2low - b_o2low;
		return a_o2 - b_o2;
	}
	return a_he - b_he;
}

#define UTF8_ELLIPSIS "\xE2\x80\xA6"

static void nitrox_data_func(GtkTreeViewColumn *col,
			     GtkCellRenderer *renderer,
			     GtkTreeModel *model,
			     GtkTreeIter *iter,
			     gpointer data)
{
	int idx, o2, he, o2low;
	char buffer[80];
	struct dive *dive;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, -1);
	if (idx < 0) {
		*buffer = '\0';
		goto exit;
	}
	dive = get_dive(idx);
	get_dive_gas(dive, &o2, &he, &o2low);
	o2 = (o2 + 5) / 10;
	he = (he + 5) / 10;
	o2low = (o2low + 5) / 10;

	if (he)
		snprintf(buffer, sizeof(buffer), "%d/%d", o2, he);
	else if (o2)
		if (o2 == o2low)
			snprintf(buffer, sizeof(buffer), "%d", o2);
		else
			snprintf(buffer, sizeof(buffer), "%d" UTF8_ELLIPSIS "%d", o2low, o2);
	else
		strcpy(buffer, "air");
exit:
	g_object_set(renderer, "text", buffer, NULL);
}

/* Render the SAC data (integer value of "ml / min") */
static void sac_data_func(GtkTreeViewColumn *col,
			  GtkCellRenderer *renderer,
			  GtkTreeModel *model,
			  GtkTreeIter *iter,
			  gpointer data)
{
	int value, idx;
	const char *fmt;
	char buffer[16];
	double sac;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_SAC, &value, -1);

	if (idx < 0 || !value) {
		*buffer = '\0';
		goto exit;
	}

	sac = value / 1000.0;
	switch (output_units.volume) {
	case LITER:
		fmt = "%4.1f";
		break;
	case CUFT:
		fmt = "%4.2f";
		sac = ml_to_cuft(sac * 1000);
		break;
	}
	snprintf(buffer, sizeof(buffer), fmt, sac);
exit:
	g_object_set(renderer, "text", buffer, NULL);
}

/* Render the OTU data (integer value of "OTU") */
static void otu_data_func(GtkTreeViewColumn *col,
			  GtkCellRenderer *renderer,
			  GtkTreeModel *model,
			  GtkTreeIter *iter,
			  gpointer data)
{
	int value, idx;
	char buffer[16];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_OTU, &value, -1);

	if (idx < 0 || !value)
		*buffer = '\0';
	else
		snprintf(buffer, sizeof(buffer), "%d", value);

	g_object_set(renderer, "text", buffer, NULL);
}

/* calculate OTU for a dive */
static int calculate_otu(struct dive *dive)
{
	int i;
	double otu = 0.0;

	for (i = 1; i < dive->samples; i++) {
		int t;
		double po2;
		struct sample *sample = dive->sample + i;
		struct sample *psample = sample - 1;
		t = sample->time.seconds - psample->time.seconds;
		int o2 = dive->cylinder[sample->cylinderindex].gasmix.o2.permille;
		if (!o2)
			o2 = AIR_PERMILLE;
		po2 = o2 / 1000.0 * (sample->depth.mm + 10000) / 10000.0;
		if (po2 >= 0.5)
			otu += pow(po2 - 0.5, 0.83) * t / 30.0;
	}
	return otu + 0.5;
}
/*
 * Return air usage (in liters).
 */
static double calculate_airuse(struct dive *dive)
{
	double airuse = 0;
	int i;

	for (i = 0; i < MAX_CYLINDERS; i++) {
		pressure_t start, end;
		cylinder_t *cyl = dive->cylinder + i;
		int size = cyl->type.size.mliter;
		double kilo_atm;

		if (!size)
			continue;

		start = cyl->start.mbar ? cyl->start : cyl->sample_start;
		end = cyl->end.mbar ? cyl->end : cyl->sample_end;
		kilo_atm = (to_ATM(start) - to_ATM(end)) / 1000.0;

		/* Liters of air at 1 atm == milliliters at 1k atm*/
		airuse += kilo_atm * size;
	}
	return airuse;
}

static int calculate_sac(struct dive *dive)
{
	double airuse, pressure, sac;
	int duration, i;

	airuse = calculate_airuse(dive);
	if (!airuse)
		return 0;
	if (!dive->duration.seconds)
		return 0;

	/* find and eliminate long surface intervals */
	duration = dive->duration.seconds;
	for (i = 0; i < dive->samples; i++) {
		if (dive->sample[i].depth.mm < 100) { /* less than 10cm */
			int end = i + 1;
			while (end < dive->samples && dive->sample[end].depth.mm < 100)
				end++;
			/* we only want the actual surface time during a dive */
			if (end < dive->samples) {
				end--;
				duration -= dive->sample[end].time.seconds -
						dive->sample[i].time.seconds;
				i = end + 1;
			}
		}
	}
	/* Mean pressure in atm: 1 atm per 10m */
	pressure = 1 + (dive->meandepth.mm / 10000.0);
	sac = airuse / pressure * 60 / duration;

	/* milliliters per minute.. */
	return sac * 1000;
}

void update_cylinder_related_info(struct dive *dive)
{
	if (dive != NULL) {
		dive->sac = calculate_sac(dive);
		dive->otu = calculate_otu(dive);
	}
}

static void get_string(char **str, const char *s)
{
	int len;
	char *n;

	if (!s)
		s = "";
	len = strlen(s);
	if (len > 60)
		len = 60;
	n = malloc(len+1);
	memcpy(n, s, len);
	n[len] = 0;
	*str = n;
}

static void get_location(struct dive *dive, char **str)
{
	get_string(str, dive->location);
}

static void get_cylinder(struct dive *dive, char **str)
{
	get_string(str, dive->cylinder[0].type.description);
}

static void get_suit(struct dive *dive, char **str)
{
	get_string(str, dive->suit);
}

/*
 * Set up anything that could have changed due to editing
 * of dive information; we need to do this for both models,
 * so we simply call set_one_dive again with the non-current model
 */
/* forward declaration for recursion */
static gboolean set_one_dive(GtkTreeModel *model,
			     GtkTreePath *path,
			     GtkTreeIter *iter,
			     gpointer data);

static void fill_one_dive(struct dive *dive,
			  GtkTreeModel *model,
			  GtkTreeIter *iter)
{
	char *location, *cylinder, *suit;
	GtkTreeModel *othermodel;

	get_cylinder(dive, &cylinder);
	get_location(dive, &location);
	get_suit(dive, &suit);

	gtk_tree_store_set(GTK_TREE_STORE(model), iter,
		DIVE_NR, dive->number,
		DIVE_LOCATION, location,
		DIVE_CYLINDER, cylinder,
		DIVE_RATING, dive->rating,
		DIVE_SAC, dive->sac,
		DIVE_OTU, dive->otu,
		DIVE_TOTALWEIGHT, total_weight(dive),
		DIVE_SUIT, suit,
		-1);

	free(location);
	free(cylinder);
	free(suit);

	if (model == TREEMODEL(dive_list))
		othermodel = LISTMODEL(dive_list);
	else
		othermodel = TREEMODEL(dive_list);
	if (othermodel != MODEL(dive_list))
		/* recursive call */
		gtk_tree_model_foreach(othermodel, set_one_dive, dive);
}

static gboolean set_one_dive(GtkTreeModel *model,
			     GtkTreePath *path,
			     GtkTreeIter *iter,
			     gpointer data)
{
	int idx;
	struct dive *dive;

	/* Get the dive number */
	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, -1);
	if (idx < 0)
		return FALSE;
	dive = get_dive(idx);
	if (!dive)
		return TRUE;
	if (data && dive != data)
		return FALSE;

	fill_one_dive(dive, model, iter);
	return dive == data;
}

void flush_divelist(struct dive *dive)
{
	GtkTreeModel *model = MODEL(dive_list);

	gtk_tree_model_foreach(model, set_one_dive, dive);
}

void set_divelist_font(const char *font)
{
	PangoFontDescription *font_desc = pango_font_description_from_string(font);
	gtk_widget_modify_font(dive_list.tree_view, font_desc);
	pango_font_description_free(font_desc);
}

void update_dive_list_units(void)
{
	const char *unit;
	GtkTreeModel *model = MODEL(dive_list);

	(void) get_depth_units(0, NULL, &unit);
	gtk_tree_view_column_set_title(dive_list.depth, unit);

	(void) get_temp_units(0, &unit);
	gtk_tree_view_column_set_title(dive_list.temperature, unit);

	(void) get_weight_units(0, NULL, &unit);
	gtk_tree_view_column_set_title(dive_list.totalweight, unit);

	gtk_tree_model_foreach(model, set_one_dive, NULL);
}

void update_dive_list_col_visibility(void)
{
	gtk_tree_view_column_set_visible(dive_list.cylinder, visible_cols.cylinder);
	gtk_tree_view_column_set_visible(dive_list.temperature, visible_cols.temperature);
	gtk_tree_view_column_set_visible(dive_list.totalweight, visible_cols.totalweight);
	gtk_tree_view_column_set_visible(dive_list.suit, visible_cols.suit);
	gtk_tree_view_column_set_visible(dive_list.nitrox, visible_cols.nitrox);
	gtk_tree_view_column_set_visible(dive_list.sac, visible_cols.sac);
	gtk_tree_view_column_set_visible(dive_list.otu, visible_cols.otu);
	return;
}

/*
 * helper functions for dive_trip handling
 */

#ifdef DEBUG_TRIP
static void dump_trip_list(void)
{
	GList *p = NULL;
	int i=0;
	timestamp_t last_time = 0;
	while ((p = NEXT_TRIP(p))) {
		dive_trip_t *dive_trip = DIVE_TRIP(p);
		struct tm tm;
		utc_mkdate(dive_trip->when, &tm);
		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) {
			utc_mkdate(dive_trip->when_from_file, &tm);
			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");
}
#endif

/* this finds a trip that starts at precisely the time given */
static GList *find_trip(timestamp_t when)
{
	GList *trip = dive_trip_list;
	while (trip && DIVE_TRIP(trip)->when < when)
		trip = trip->next;
	if (DIVE_TRIP(trip)->when == when) {
#ifdef DEBUG_TRIP
		struct tm tm;
		utc_mkdate(DIVE_TRIP(trip)->when, &tm);
		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;
	}
#ifdef DEBUG_TRIP
	printf("no matching trip\n");
#endif
	return NULL;
}

/* this finds the last trip that at or before the time given */
static GList *find_matching_trip(timestamp_t when)
{
	GList *trip = dive_trip_list;
	if (!trip || DIVE_TRIP(trip)->when > when) {
#ifdef DEBUG_TRIP
		printf("no matching trip\n");
#endif
		return NULL;
	}
	while (trip->next && DIVE_TRIP(trip->next)->when <= when)
		trip = trip->next;
#ifdef DEBUG_TRIP
	{
		struct tm tm;
		utc_mkdate(DIVE_TRIP(trip)->when, &tm);
		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;
}

/* 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 */
void insert_trip(dive_trip_t **dive_trip_p)
{
	dive_trip_t *dive_trip = *dive_trip_p;
	GList *trip = dive_trip_list;
	while (trip && DIVE_TRIP(trip)->when < dive_trip->when)
		trip = trip->next;
	if (trip && DIVE_TRIP(trip)->when == dive_trip->when) {
		if (! DIVE_TRIP(trip)->location)
			DIVE_TRIP(trip)->location = dive_trip->location;
		*dive_trip_p = DIVE_TRIP(trip);
	} else {
		dive_trip_list = g_list_insert_before(dive_trip_list, trip, *dive_trip_p);
	}
#ifdef DEBUG_TRIP
	dump_trip_list();
#endif
}

static inline void delete_trip(GList *trip)
{
	dive_trip_list = g_list_delete_link(dive_trip_list, trip);
#ifdef DEBUG_TRIP
	dump_trip_list();
#endif
}
static dive_trip_t *create_and_hookup_trip_from_dive(struct dive *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);
	insert_trip(&dive_trip);
	dive->divetrip = dive_trip;
	dive->tripflag = IN_TRIP;
	return dive_trip;
}

/* check that a dive should be in a trip starting at 'when'
 * first the regular check (dive is before the trip start, but within the
 * threshold)
 * then for dives that are after the trip start we walk back to the 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, dive_trip_t *dive_trip)
{
	struct dive *dive, *pdive;
	int i = idx;
	timestamp_t when = dive_trip->when;

	dive = get_dive(idx);
	/* if the dive is before the trip start but within the threshold
	 * then just accept it, otherwise reject it */
	if (dive->when < when) {
		if (DIVE_FITS_TRIP(dive, dive_trip))
			return TRUE;
		else
			return FALSE;
	}

	while (--i >= 0) {
		pdive = get_dive(i);
		/* an ungrouped dive cannot be in the middle of a trip
		 * also, if there are two consecutive dives that are too far apart
		 * that aren't both already labeled as 'in trip' (which shows that
		 * this was manually done so we shouldn't override that) */
		if ( UNGROUPED_DIVE(pdive) ||
			(! (DIVE_IN_TRIP(pdive) && DIVE_IN_TRIP(dive)) &&
			 dive->when - pdive->when > TRIP_THRESHOLD)) {
			return FALSE;
		}
		if (pdive->when == when)
			/* done - we have reached the first dive in the trip */
			return TRUE;
		dive = pdive;
	}
	/* we should never get here */
	return TRUE;
}

static void fill_dive_list(void)
{
	int i;
	GtkTreeIter iter, parent_iter, *parent_ptr = NULL;
	GtkTreeStore *liststore, *treestore;
	dive_trip_t *last_trip = NULL;
	GList *trip;
	dive_trip_t *dive_trip = NULL;

	/* if we have pre-existing trips, start on the last one */
	trip = g_list_last(dive_trip_list);

	treestore = TREESTORE(dive_list);
	liststore = LISTSTORE(dive_list);

	i = dive_table.nr;
	while (--i >= 0) {
		struct dive *dive = get_dive(i);

		/* make sure we display the first date of the trip in previous summary */
		if (dive_trip && parent_ptr) {
			gtk_tree_store_set(treestore, parent_ptr,
					DIVE_DATE, dive_trip->when,
					DIVE_LOCATION, dive_trip->location,
					-1);
		}
		/* the dive_trip info might have been killed by a previous UNGROUPED dive */
		if (trip)
			dive_trip = DIVE_TRIP(trip);
		/* tripflag defines how dives are handled;
		 * TF_NONE "not handled yet" - create time based group if autogroup == TRUE
		 * NO_TRIP "set as no group" - simply leave at top level
		 * IN_TRIP "use the trip with the largest trip time (when) that is <= this dive"
		 */
		if (UNGROUPED_DIVE(dive)) {
			/* first dives that go to the top level */
			parent_ptr = NULL;
			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 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 = AUTOGEN_TRIP;
					trip = find_trip(dive_trip->when);
				}
			}
			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 {
			/* dive is not in a trip and we aren't autogrouping */
			dive_trip = NULL;
			parent_ptr = NULL;
		}
		/* update dive as part of dive_trip and
		 * (if necessary) update dive_trip time and location */
		if (dive_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;
			if (!dive_trip->location && dive->location)
				dive_trip->location = dive->location;
			if (dive_trip != last_trip) {
				last_trip = dive_trip;
				/* create trip entry */
				gtk_tree_store_append(treestore, &parent_iter, NULL);
				parent_ptr = &parent_iter;
				/* a duration of 0 (and negative index) identifies a group */
				gtk_tree_store_set(treestore, parent_ptr,
						DIVE_INDEX, -1,
						DIVE_DATE, dive_trip->when,
						DIVE_LOCATION, dive_trip->location,
						DIVE_DURATION, 0,
						-1);
			}
		}

		/* store dive */
		update_cylinder_related_info(dive);
		gtk_tree_store_append(treestore, &iter, parent_ptr);
		gtk_tree_store_set(treestore, &iter,
			DIVE_INDEX, i,
			DIVE_NR, dive->number,
			DIVE_DATE, dive->when,
			DIVE_DEPTH, dive->maxdepth,
			DIVE_DURATION, dive->duration.seconds,
			DIVE_LOCATION, dive->location,
			DIVE_RATING, dive->rating,
			DIVE_TEMPERATURE, dive->watertemp.mkelvin,
			DIVE_SAC, 0,
			-1);
		gtk_tree_store_append(liststore, &iter, NULL);
		gtk_tree_store_set(liststore, &iter,
			DIVE_INDEX, i,
			DIVE_NR, dive->number,
			DIVE_DATE, dive->when,
			DIVE_DEPTH, dive->maxdepth,
			DIVE_DURATION, dive->duration.seconds,
			DIVE_LOCATION, dive->location,
			DIVE_RATING, dive->rating,
			DIVE_TEMPERATURE, dive->watertemp.mkelvin,
			DIVE_TOTALWEIGHT, 0,
			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 */
	if (parent_ptr && dive_trip)
		gtk_tree_store_set(treestore, parent_ptr,
				DIVE_DATE, dive_trip->when,
				DIVE_LOCATION, dive_trip->location,
				-1);
	update_dive_list_units();
	if (amount_selected == 0 && gtk_tree_model_get_iter_first(MODEL(dive_list), &iter)) {
		GtkTreeSelection *selection;

		/* select the last dive (and make sure it's an actual dive that is selected) */
		gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &selected_dive, -1);
		first_leaf(MODEL(dive_list), &iter, &selected_dive);
		selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));
		gtk_tree_selection_select_iter(selection, &iter);
	}
}

void dive_list_update_dives(void)
{
	gtk_tree_store_clear(TREESTORE(dive_list));
	gtk_tree_store_clear(LISTSTORE(dive_list));
	fill_dive_list();
	repaint_dive();
}

static struct divelist_column {
	const char *header;
	data_func_t data;
	sort_func_t sort;
	unsigned int flags;
	int *visible;
} dl_column[] = {
	[DIVE_NR] = { "#", nr_data_func, NULL, ALIGN_RIGHT | UNSORTABLE },
	[DIVE_DATE] = { "Date", date_data_func, NULL, ALIGN_LEFT },
	[DIVE_RATING] = { UTF8_BLACKSTAR, star_data_func, NULL, ALIGN_LEFT },
	[DIVE_DEPTH] = { "ft", depth_data_func, NULL, ALIGN_RIGHT },
	[DIVE_DURATION] = { "min", duration_data_func, NULL, ALIGN_RIGHT },
	[DIVE_TEMPERATURE] = { UTF8_DEGREE "F", temperature_data_func, NULL, ALIGN_RIGHT, &visible_cols.temperature },
	[DIVE_TOTALWEIGHT] = { "lbs", weight_data_func, NULL, ALIGN_RIGHT, &visible_cols.totalweight },
	[DIVE_SUIT] = { "Suit", NULL, NULL, ALIGN_LEFT, &visible_cols.suit },
	[DIVE_CYLINDER] = { "Cyl", NULL, NULL, 0, &visible_cols.cylinder },
	[DIVE_NITROX] = { "O" UTF8_SUBSCRIPT_2 "%", nitrox_data_func, nitrox_sort_func, 0, &visible_cols.nitrox },
	[DIVE_SAC] = { "SAC", sac_data_func, NULL, 0, &visible_cols.sac },
	[DIVE_OTU] = { "OTU", otu_data_func, NULL, 0, &visible_cols.otu },
	[DIVE_LOCATION] = { "Location", NULL, NULL, ALIGN_LEFT },
};


static GtkTreeViewColumn *divelist_column(struct DiveList *dl, struct divelist_column *col)
{
	int index = col - &dl_column[0];
	const char *title = col->header;
	data_func_t data_func = col->data;
	sort_func_t sort_func = col->sort;
	unsigned int flags = col->flags;
	int *visible = col->visible;
	GtkWidget *tree_view = dl->tree_view;
	GtkTreeStore *treemodel = dl->treemodel;
	GtkTreeStore *listmodel = dl->listmodel;
	GtkTreeViewColumn *ret;

	if (visible && !*visible)
		flags |= INVISIBLE;
	ret = tree_view_column(tree_view, index, title, data_func, flags);
	if (sort_func) {
		/* the sort functions are needed in the corresponding models */
		if (index == DIVE_DATE)
			gtk_tree_sortable_set_sort_func(GTK_TREE_SORTABLE(treemodel), index, sort_func, NULL, NULL);
		else
			gtk_tree_sortable_set_sort_func(GTK_TREE_SORTABLE(listmodel), index, sort_func, NULL, NULL);
	}
	return ret;
}

/*
 * This is some crazy crap. The only way to get default focus seems
 * to be to grab focus as the widget is being shown the first time.
 */
static void realize_cb(GtkWidget *tree_view, gpointer userdata)
{
	gtk_widget_grab_focus(tree_view);
}

/*
 * Double-clicking on a group entry will expand a collapsed group
 * and vice versa.
 */
static void collapse_expand(GtkTreeView *tree_view, GtkTreePath *path)
{
	if (!gtk_tree_view_row_expanded(tree_view, path))
		gtk_tree_view_expand_row(tree_view, path, FALSE);
	else
		gtk_tree_view_collapse_row(tree_view, path);

}

/* Double-click on a dive list */
static void row_activated_cb(GtkTreeView *tree_view,
			GtkTreePath *path,
			GtkTreeViewColumn *column,
			gpointer userdata)
{
	int index;
	GtkTreeIter iter;

	if (!gtk_tree_model_get_iter(MODEL(dive_list), &iter, path))
		return;

	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &index, -1);
	/* a negative index is special for the "group by date" entries */
	if (index < 0) {
		collapse_expand(tree_view, path);
		return;
	}
	edit_dive_info(get_dive(index));
}

void add_dive_cb(GtkWidget *menuitem, gpointer data)
{
	struct dive *dive;

	dive = alloc_dive();
	if (add_new_dive(dive)) {
		record_dive(dive);
		report_dives(TRUE);
		return;
	}
	free(dive);
}

void edit_trip_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	GtkTreeIter iter;
	timestamp_t when;
	dive_trip_t *dive_trip;
	GList *trip;

	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_DATE, &when, -1);
	trip = find_trip(when);
	dive_trip = DIVE_TRIP(trip);
	if (edit_trip(dive_trip))
		gtk_tree_store_set(STORE(dive_list), &iter, DIVE_LOCATION, dive_trip->location, -1);
}

void edit_selected_dives_cb(GtkWidget *menuitem, gpointer data)
{
	edit_multi_dive_info(NULL);
}

void edit_dive_from_path_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	struct dive *dive = dive_from_path(path);

	edit_multi_dive_info(dive);
}

static void expand_all_cb(GtkWidget *menuitem, GtkTreeView *tree_view)
{
	gtk_tree_view_expand_all(tree_view);
}

static void collapse_all_cb(GtkWidget *menuitem, GtkTreeView *tree_view)
{
	gtk_tree_view_collapse_all(tree_view);
}

/* copy the node and return the index */
static int copy_tree_node(GtkTreeIter *a, GtkTreeIter *b)
{
	struct dive store_dive;
	int totalweight, idx;
	char *cylinder_text;

	gtk_tree_model_get(MODEL(dive_list), a,
		DIVE_INDEX, &idx,
		DIVE_NR, &store_dive.number,
		DIVE_DATE, &store_dive.when,
		DIVE_RATING, &store_dive.rating,
		DIVE_DEPTH, &store_dive.maxdepth,
		DIVE_DURATION, &store_dive.duration,
		DIVE_TEMPERATURE, &store_dive.watertemp.mkelvin,
		DIVE_TOTALWEIGHT, &totalweight,
		DIVE_SUIT, &store_dive.suit,
		DIVE_CYLINDER, &cylinder_text,
		DIVE_SAC, &store_dive.sac,
		DIVE_OTU, &store_dive.otu,
		DIVE_LOCATION, &store_dive.location,
		-1);
	gtk_tree_store_set(STORE(dive_list), b,
		DIVE_INDEX, idx,
		DIVE_NR, store_dive.number,
		DIVE_DATE, store_dive.when,
		DIVE_RATING, store_dive.rating,
		DIVE_DEPTH, store_dive.maxdepth,
		DIVE_DURATION, store_dive.duration,
		DIVE_TEMPERATURE, store_dive.watertemp.mkelvin,
		DIVE_TOTALWEIGHT, totalweight,
		DIVE_SUIT, store_dive.suit,
		DIVE_CYLINDER, cylinder_text,
		DIVE_SAC, store_dive.sac,
		DIVE_OTU, store_dive.otu,
		DIVE_LOCATION, store_dive.location,
		-1);
	free(cylinder_text);
	free(store_dive.location);
	free(store_dive.suit);
	return idx;
}

/* to avoid complicated special cases based on ordering or number of children,
   we always take the first and last child and pick the smaller timestamp_t (which
   works regardless of ordering and also with just one child) */
static void update_trip_timestamp(GtkTreeIter *parent, dive_trip_t *divetrip)
{
	GtkTreeIter first_child, last_child;
	int nr;
	timestamp_t t1, t2, tnew;

	if (gtk_tree_store_iter_depth(STORE(dive_list), parent) != 0 ||
		gtk_tree_model_iter_n_children(MODEL(dive_list), parent) == 0)
		return;
	nr = gtk_tree_model_iter_n_children(MODEL(dive_list), parent);
	gtk_tree_model_iter_nth_child(MODEL(dive_list), &first_child, parent, 0);
	gtk_tree_model_get(MODEL(dive_list), &first_child, DIVE_DATE, &t1, -1);
	gtk_tree_model_iter_nth_child(MODEL(dive_list), &last_child, parent, nr - 1);
	gtk_tree_model_get(MODEL(dive_list), &last_child, DIVE_DATE, &t2, -1);
	tnew = MIN(t1, t2);
	gtk_tree_store_set(STORE(dive_list), parent, DIVE_DATE, tnew, -1);
	if (divetrip)
		divetrip->when = tnew;
}

/* move dive_iter, which is a child of old_trip (could be NULL) to new_trip (could be NULL);
 * either of the trips being NULL means that this was (or will be) a dive without a trip;
 * update the dive trips (especially the starting times) accordingly
 * maintain the selected status of the dive
 * IMPORTANT - the move needs to keep the tree consistant - so no out of order moving... */
static GtkTreeIter *move_dive_between_trips(GtkTreeIter *dive_iter, GtkTreeIter *old_trip, GtkTreeIter *new_trip,
					GtkTreeIter *sibling, gboolean before)
{
	int idx;
	timestamp_t old_when, new_when;
	struct dive *dive;
	dive_trip_t *old_divetrip, *new_divetrip;
	GtkTreeIter *new_iter = malloc(sizeof(GtkTreeIter));

	if (before)
		gtk_tree_store_insert_before(STORE(dive_list), new_iter, new_trip, sibling);
	else
		gtk_tree_store_insert_after(STORE(dive_list), new_iter, new_trip, sibling);
	idx = copy_tree_node(dive_iter, new_iter);
	gtk_tree_model_get(MODEL(dive_list), new_iter, DIVE_INDEX, &idx, -1);
	dive = get_dive(idx);
	gtk_tree_store_remove(STORE(dive_list), dive_iter);
	if (old_trip) {
		gtk_tree_model_get(MODEL(dive_list), old_trip, DIVE_DATE, &old_when, -1);
		old_divetrip = DIVE_TRIP(find_matching_trip(old_when));
		update_trip_timestamp(old_trip, old_divetrip);
	}
	if (new_trip) {
		gtk_tree_model_get(MODEL(dive_list), new_trip, DIVE_DATE, &new_when, -1);
		new_divetrip = dive->divetrip;
		update_trip_timestamp(new_trip, new_divetrip);
	}
	if (dive->selected) {
		GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));
		gtk_tree_selection_select_iter(selection, new_iter);
	}
	return new_iter;
}

/* this gets called when we are on a top level dive and we know that the previous
 * top level node is a trip; if multiple consecutive dives are selected, they are
 * all merged into the previous trip*/
static void merge_dive_into_trip_above_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	int idx;
	GtkTreeIter dive_iter, trip_iter, prev_iter;
	GtkTreePath *trip_path;
	struct dive *dive, *prev_dive;

	/* get the path and iter for the trip and the last dive of that trip */
	trip_path = gtk_tree_path_copy(path);
	(void)gtk_tree_path_prev(trip_path);
	gtk_tree_model_get_iter(MODEL(dive_list), &trip_iter, trip_path);
	gtk_tree_model_get_iter(MODEL(dive_list), &dive_iter, path);
	gtk_tree_model_iter_nth_child(MODEL(dive_list), &prev_iter, &trip_iter,
				gtk_tree_model_iter_n_children(MODEL(dive_list), &trip_iter) - 1);
	gtk_tree_model_get(MODEL(dive_list), &dive_iter, DIVE_INDEX, &idx, -1);
	dive = get_dive(idx);
	gtk_tree_model_get(MODEL(dive_list), &prev_iter, DIVE_INDEX, &idx, -1);
	prev_dive = get_dive(idx);
	/* add the dive to the trip */
	for (;;) {
		dive->divetrip = prev_dive->divetrip;
		/* we intentionally changed the dive_trip, so update the time
		 * stamp that we fall back to when toggling autogroup */
		dive->divetrip->when_from_file = dive->divetrip->when;
		dive->tripflag = IN_TRIP;
		(void)move_dive_between_trips(&dive_iter, NULL, &trip_iter, NULL, TRUE);
		prev_dive = dive;
		/* by merging the dive into the trip above the path now points to the next
		   top level entry. If that iter exists, it's also a dive and both this dive
		   and that next dive are selected, continue merging dives into the trip */
		if (!gtk_tree_model_get_iter(MODEL(dive_list), &dive_iter, path))
			break;
		gtk_tree_model_get(MODEL(dive_list), &dive_iter, DIVE_INDEX, &idx, -1);
		if (idx < 0)
			break;
		dive = get_dive(idx);
		if (!dive->selected || !prev_dive->selected)
			break;
	}
	mark_divelist_changed(TRUE);
}

static void turn_dive_into_trip(GtkTreePath *path)
{
	GtkTreeIter iter, *newiter, newparent;
	GtkTreePath *treepath;
	timestamp_t when;
	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 */
	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	gtk_tree_store_insert_after(STORE(dive_list), &newparent, NULL, &iter);
	gtk_tree_model_get(MODEL(dive_list), &iter,
			DIVE_INDEX, &idx, DIVE_DATE, &when, DIVE_LOCATION, &location, -1);
	gtk_tree_store_set(STORE(dive_list), &newparent,
			DIVE_INDEX, -1, DIVE_DATE, when, DIVE_LOCATION, location, -1);
	free(location);
	newiter = move_dive_between_trips(&iter, NULL, &newparent, NULL, FALSE);
	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);
	/* 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 */
static void insert_trip_before(GtkTreePath *path)
{
	GtkTreeIter iter, prev_iter, parent, newparent, nextsibling;
	GtkTreePath *treepath, *prev_path;
	struct dive *dive, *prev_dive;
	dive_trip_t *new_divetrip;
	int idx, nr, i;

	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	prev_path = gtk_tree_path_copy(path);
	if (!gtk_tree_path_prev(prev_path) ||
	    !gtk_tree_model_iter_parent(MODEL(dive_list), &parent, &iter))
		return;
	gtk_tree_model_get_iter(MODEL(dive_list), &prev_iter, prev_path);
	gtk_tree_model_get(MODEL(dive_list), &prev_iter, DIVE_INDEX, &idx, -1);
	prev_dive = get_dive(idx);
	gtk_tree_store_insert_after(STORE(dive_list), &newparent, NULL, &parent);
	copy_tree_node(&parent, &newparent);
	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &idx, -1);
	dive = get_dive(idx);
	/* make sure that the timestamp_t of the previous divetrip is correct before
	 * inserting a new one */
	if (dive->when < prev_dive->when)
		if (prev_dive->divetrip && prev_dive->divetrip->when < prev_dive->when)
			prev_dive->divetrip->when = prev_dive->when;
	new_divetrip = create_and_hookup_trip_from_dive(dive);

	/* in order for the data structures to stay consistent we need to walk from
	 * the last child backwards to this one. The easiest way seems to be to do
	 * this with the nth iterator API */
	nr = gtk_tree_model_iter_n_children(MODEL(dive_list), &parent);
	for (i = nr - 1; i >= 0; i--) {
		gtk_tree_model_iter_nth_child(MODEL(dive_list), &nextsibling, &parent, i);
		treepath = gtk_tree_model_get_path(MODEL(dive_list), &nextsibling);
		gtk_tree_model_get(MODEL(dive_list), &nextsibling, DIVE_INDEX, &idx, -1);
		dive = get_dive(idx);
		dive->divetrip = new_divetrip;
		if (dive->when < dive->divetrip->when)
			dive->divetrip->when = dive->when;
		(void) move_dive_between_trips(&nextsibling, &parent, &newparent, NULL, FALSE);
		if (gtk_tree_path_compare(path, treepath) == 0)
			/* 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
	dump_trip_list();
#endif
}

static void insert_trip_before_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	/* is this splitting a trip or turning a dive into a trip? */
	if (gtk_tree_path_get_depth(path) == 2) {
		insert_trip_before(path);
	} else { /* this is a top level dive */
		struct dive *dive, *next_dive;
		GtkTreePath *next_path;

		dive = dive_from_path(path);
		turn_dive_into_trip(path);
		/* if the dive was selected and the next dive was selected, too,
		 * then all of them should be part of the new trip */
		if (dive->selected) {
			next_path = gtk_tree_path_copy(path);
			gtk_tree_path_next(next_path);
			next_dive = dive_from_path(next_path);
			if (next_dive && next_dive->selected)
				merge_dive_into_trip_above_cb(menuitem, next_path);
		}
	}
	mark_divelist_changed(TRUE);
}

static void remove_from_trip(GtkTreePath *path)
{
	GtkTreeIter iter, nextiter, *newiter, parent;
	GtkTreePath *nextpath;
	struct dive *dive;
	int idx;

	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	if (!gtk_tree_model_iter_parent(MODEL(dive_list), &parent, &iter))
		return;
	/* if this isn't the last dive in a trip we simply split the trip
	   in two right after this dive */
	nextpath = gtk_tree_path_copy(path);
	gtk_tree_path_next(nextpath);
	if (gtk_tree_model_get_iter(MODEL(dive_list), &nextiter, nextpath))
		insert_trip_before(nextpath);
	/* now move the dive to the top level, as sibling after its former parent */
	newiter = move_dive_between_trips(&iter, &parent, NULL, &parent, FALSE);
	gtk_tree_model_get(MODEL(dive_list), newiter, DIVE_INDEX, &idx, -1);
	dive = get_dive(idx);
	if (dive->selected) {
		GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));
		gtk_tree_selection_select_iter(selection, newiter);
	}
	/* if this was the last dive on the trip, remove the trip */
	if (! gtk_tree_model_iter_has_child(MODEL(dive_list), &parent)) {
		gtk_tree_store_remove(STORE(dive_list), &parent);
		delete_trip(find_trip(dive->divetrip->when));
		free(dive->divetrip);
	}
	/* mark the dive as intentionally at the top level */
	dive->tripflag = NO_TRIP;
	dive->divetrip = NULL;
#ifdef DEBUG_TRIP
	dump_trip_list();
#endif
}

static void remove_rowref_from_trip(gpointer data, gpointer user_data)
{
	GtkTreeRowReference *rowref = data;
	GtkTreePath *path = gtk_tree_row_reference_get_path(rowref);
	if (path)
		remove_from_trip(path);
}

static gboolean add_rowref_if_selected(GtkTreeModel *model, GtkTreePath *path,
					GtkTreeIter *iter, gpointer data)
{
	GList **rowref_list = data;
	int idx;
	struct dive *dive;

	gtk_tree_model_get(MODEL(dive_list), iter, DIVE_INDEX, &idx, -1);
	if (idx >=0 ) {
		dive = get_dive(idx);
		if (dive->selected) {
			/* we need to store the Row References as those
			   stay valid across modifications of the model */
			GtkTreeRowReference *rowref;
			rowref = gtk_tree_row_reference_new(TREEMODEL(dive_list), path);
			*rowref_list = g_list_append(*rowref_list, rowref);
		}
	}
	return FALSE; /* continue foreach loop */
}

static void remove_from_trip_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	GtkTreeIter iter, parent;
	struct dive *dive;
	int idx;

	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	if (!gtk_tree_model_iter_parent(MODEL(dive_list), &parent, &iter))
		return;
	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &idx, -1);
	if (idx < 0 )
		return;
	dive = get_dive(idx);
	if (dive->selected) {
		/* remove all the selected dives
		   since removing the dives from trips changes the model we need to
		   take the extra step of acquiring rowrefs before actually moving dives */
		GList *rowref_list = NULL;
		gtk_tree_model_foreach(MODEL(dive_list), add_rowref_if_selected, &rowref_list);
		/* We need to walk that list backwards as otherwise
		   the newly insered trips below dives that were
		   removed also mess with the validity */
		rowref_list = g_list_reverse(rowref_list);
		g_list_foreach(rowref_list, remove_rowref_from_trip, NULL);

	} else {
		/* just remove the dive the mouse pointer is on */
		remove_from_trip(path);
	}
	mark_divelist_changed(TRUE);
}

void remove_trip(GtkTreePath *trippath, gboolean force_no_trip)
{
	GtkTreeIter newiter, parent, child, *lastiter = &parent;
	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));

	/* what a pain - we can't just move the nodes, we have to
	 * create new ones and delete the existing ones instead */
	gtk_tree_model_get_iter(MODEL(dive_list), &parent, trippath);
	childpath = gtk_tree_path_copy(trippath);
	gtk_tree_path_down(childpath);
	for (;;) {
		if( ! gtk_tree_model_get_iter(MODEL(dive_list), &child, childpath))
			break;
		gtk_tree_store_insert_after(STORE(dive_list), &newiter, NULL, lastiter);
		copy_tree_node(&child, &newiter);
		/* we need to track what was selected */
		gtk_tree_model_get(MODEL(dive_list), &child, DIVE_INDEX, &idx, -1);
		dive = get_dive(idx);
		if (dive->selected)
			gtk_tree_selection_select_iter(selection, &newiter);
		if (force_no_trip)
			dive->tripflag = NO_TRIP;
		else
			dive->tripflag = TF_NONE;
		if (!dive_trip)
			dive_trip = dive->divetrip;
		dive->divetrip = NULL;
		/* this removes the child - now childpath points to the next child */
		gtk_tree_store_remove(STORE(dive_list), &child);
		lastiter = &newiter;
	}
	/* finally, remove the trip */
	gtk_tree_store_remove(STORE(dive_list), &parent);
	delete_trip(find_trip(dive_trip->when));
	free(dive_trip);
#ifdef DEBUG_TRIP
	dump_trip_list();
#endif
}

void remove_trip_cb(GtkWidget *menuitem, GtkTreePath *trippath)
{
	remove_trip(trippath, TRUE);
	mark_divelist_changed(TRUE);
}

void merge_trips_cb(GtkWidget *menuitem, GtkTreePath *trippath)
{
	GtkTreePath *prevpath;
	GtkTreeIter thistripiter, prevtripiter, newiter, iter;
	GtkTreeModel *tm = MODEL(dive_list);
	GList *trip, *prevtrip;
	timestamp_t when;

	/* this only gets called when we are on a trip and there is another trip right before */
	prevpath = gtk_tree_path_copy(trippath);
	gtk_tree_path_prev(prevpath);
	gtk_tree_model_get_iter(tm, &thistripiter, trippath);
	gtk_tree_model_get(tm, &thistripiter, DIVE_DATE, &when, -1);
	trip = find_matching_trip(when);
	gtk_tree_model_get_iter(tm, &prevtripiter, prevpath);
	gtk_tree_model_get(tm, &prevtripiter, DIVE_DATE, &when, -1);
	prevtrip = find_matching_trip(when);
	while (gtk_tree_model_iter_children(tm, &iter, &thistripiter)) {
		int idx;
		gtk_tree_store_insert_before(STORE(dive_list), &newiter, &prevtripiter, NULL);
		idx = copy_tree_node(&iter, &newiter);
		gtk_tree_store_remove(STORE(dive_list), &iter);
		get_dive(idx)->divetrip = DIVE_TRIP(prevtrip);
	}
	update_trip_timestamp(&prevtripiter, DIVE_TRIP(prevtrip));
	free(DIVE_TRIP(trip));
	delete_trip(trip);
	gtk_tree_store_remove(STORE(dive_list), &thistripiter);
	mark_divelist_changed(TRUE);
}

/* this implements the mechanics of removing the dive from the table,
 * but doesn't deal with updating dive trips, etc */
static void delete_single_dive(int idx)
{
	int i;
	struct dive *dive = get_dive(idx);
	if (!dive)
		return; /* this should never happen */
	for (i = idx; i < dive_table.nr - 1; i++)
		dive_table.dives[i] = dive_table.dives[i+1];
	dive_table.nr--;
	if (dive->selected)
		amount_selected--;
	free(dive);
}

/* remember expanded state */
static void remember_tree_state()
{
	GtkTreeIter iter;
	if (!gtk_tree_model_get_iter_first(TREEMODEL(dive_list), &iter))
		return;
	do {
		int idx;
		timestamp_t when;
		GtkTreePath *path;

		gtk_tree_model_get(TREEMODEL(dive_list), &iter,
				   DIVE_INDEX, &idx, DIVE_DATE, &when, -1);
		if (idx >= 0)
			continue;
		path = gtk_tree_model_get_path(TREEMODEL(dive_list), &iter);
		if (gtk_tree_view_row_expanded(GTK_TREE_VIEW(dive_list.tree_view), path))
			DIVE_TRIP(find_trip(when))->expanded = TRUE;
	} while (gtk_tree_model_iter_next(TREEMODEL(dive_list), &iter));
}

static gboolean restore_node_state(GtkTreeModel *model, GtkTreePath *path, GtkTreeIter *iter, gpointer data)
{
	int idx;
	timestamp_t when;
	struct dive *dive;
	GtkTreeView *tree_view = GTK_TREE_VIEW(dive_list.tree_view);
	GtkTreeSelection *selection = gtk_tree_view_get_selection(tree_view);

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_DATE, &when, -1);
	if (idx < 0) {
		if (DIVE_TRIP(find_trip(when))->expanded)
			gtk_tree_view_expand_row(tree_view, path, FALSE);
		if (DIVE_TRIP(find_trip(when))->selected)
			gtk_tree_selection_select_iter(selection, iter);
	} else {
		dive = get_dive(idx);
		if (dive->selected)
			gtk_tree_selection_select_iter(selection, iter);
	}
	/* continue foreach */
	return FALSE;
}

/* restore expanded and selected state */
static void restore_tree_state()
{
	gtk_tree_model_foreach(MODEL(dive_list), restore_node_state, NULL);
}

/* called when multiple dives are selected and one of these is right-clicked for delete */
static void delete_selected_dives_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	int i;
	gboolean divetrip_needs_update = FALSE;
	dive_trip_t *divetrip_to_update = NULL;
	struct dive *dive;

	remember_tree_state();
	/* walk the dive list in chronological order */
	for (i = 0; i < dive_table.nr; i++) {
		dive = get_dive(i);
		if (!dive)
			continue;
		if (! dive->selected) {
			if (divetrip_needs_update) {
				divetrip_needs_update = FALSE;
				/* this is the first unselected dive since we found the
				 * trip that needed to be updated; if we are still on the
				 * same trip, update the time, else delete the trip */
				if (dive->divetrip == divetrip_to_update)
					divetrip_to_update->when = dive->when;
				else
					delete_trip(find_trip(divetrip_to_update->when));
			}
			continue;
		}

		/* this is a selected (i.e., to be deleted) dive; if we have a divetrip
		 * that needs to be updated, check if this dive is still in that trip;
		 * if not, delete the trip */
		if (divetrip_needs_update && dive->divetrip != divetrip_to_update) {
			delete_trip(find_trip(divetrip_to_update->when));
			divetrip_needs_update = FALSE;
		}
		/* if this dive is part of a divetrip and is the first dive that
		 * determines the timestamp, then remember that divetrip for updating */
		if (dive->divetrip && dive->when == dive->divetrip->when) {
			divetrip_needs_update = TRUE;
			divetrip_to_update = dive->divetrip;
		}
		/* now remove the dive from the table and free it. also move the iterator back,
		 * so that we don't skip a dive */
		delete_single_dive(i);
		i--;
	}
	dive_list_update_dives();
	restore_tree_state();

	/* if no dives are selected at this point clear the display widgets */
	if (!amount_selected) {
		selected_dive = 0;
		process_selected_dives();
		clear_stats_widgets();
		clear_equipment_widgets();
		show_dive_info(NULL);
	}
	mark_divelist_changed(TRUE);
}

/* this gets called with path pointing to a dive, either in the top level
 * or as part of a trip */
static void delete_dive_cb(GtkWidget *menuitem, GtkTreePath *path)
{
	int idx;
	struct dive *dive;
	GtkTreeIter iter;

	remember_tree_state();
	if (!gtk_tree_model_get_iter(MODEL(dive_list), &iter, path))
		return;
	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &idx, -1);
	dive = get_dive(idx);
	/* do we need to update the trip this dive is part of? */
	if (dive->divetrip && dive->when == dive->divetrip->when) {
		struct dive *next_dive = get_dive(idx + 1);
		if (!next_dive || next_dive->divetrip != dive->divetrip)
			delete_trip(find_trip(dive->when));
		else
			next_dive->divetrip->when = next_dive->when;
	}
	delete_single_dive(idx);
	dive_list_update_dives();
	restore_tree_state();
	mark_divelist_changed(TRUE);
}

static void popup_divelist_menu(GtkTreeView *tree_view, GtkTreeModel *model, int button, GdkEventButton *event)
{
	GtkWidget *menu, *menuitem, *image;
	char editlabel[] = "Edit dives";
	char deletelabel[] = "Delete dives";
	GtkTreePath *path, *prevpath, *nextpath;
	GtkTreeIter iter, previter, nextiter;
	int idx, previdx, nextidx;
	struct dive *dive;

	if (!gtk_tree_view_get_path_at_pos(tree_view, event->x, event->y, &path, NULL, NULL, NULL))
		return;
	gtk_tree_model_get_iter(MODEL(dive_list), &iter, path);
	gtk_tree_model_get(MODEL(dive_list), &iter, DIVE_INDEX, &idx, -1);

	menu = gtk_menu_new();
	menuitem = gtk_image_menu_item_new_with_label("Add dive");
	image = gtk_image_new_from_stock(GTK_STOCK_ADD, GTK_ICON_SIZE_MENU);
	gtk_image_menu_item_set_image(GTK_IMAGE_MENU_ITEM(menuitem), image);
	g_signal_connect(menuitem, "activate", G_CALLBACK(add_dive_cb), NULL);
	gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);

	if (idx < 0) {
		/* mouse pointer is on a trip summary entry */
		menuitem = gtk_menu_item_new_with_label("Edit Trip Summary");
		g_signal_connect(menuitem, "activate", G_CALLBACK(edit_trip_cb), path);
		gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
		prevpath = gtk_tree_path_copy(path);
		if (gtk_tree_path_prev(prevpath) &&
		    gtk_tree_model_get_iter(MODEL(dive_list), &previter, prevpath)) {
			gtk_tree_model_get(MODEL(dive_list), &previter, DIVE_INDEX, &previdx, -1);
			if (previdx < 0) {
				menuitem = gtk_menu_item_new_with_label("Merge trip with trip above");
				g_signal_connect(menuitem, "activate", G_CALLBACK(merge_trips_cb), path);
				gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
			}
		}
		nextpath = gtk_tree_path_copy(path);
		gtk_tree_path_next(nextpath);
		if (gtk_tree_model_get_iter(MODEL(dive_list), &nextiter, nextpath)) {
			gtk_tree_model_get(MODEL(dive_list), &nextiter, DIVE_INDEX, &nextidx, -1);
			if (nextidx < 0) {
				menuitem = gtk_menu_item_new_with_label("Merge trip with trip below");
				g_signal_connect(menuitem, "activate", G_CALLBACK(merge_trips_cb), nextpath);
				gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
			}
		}
		menuitem = gtk_menu_item_new_with_label("Remove Trip");
		g_signal_connect(menuitem, "activate", G_CALLBACK(remove_trip_cb), path);
		gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
	} else {
		dive = get_dive(idx);
		/* if we right click on selected dive(s), edit or delete those */
		if (dive->selected) {
			if (amount_selected == 1) {
				deletelabel[strlen(deletelabel) - 1] = '\0';
				editlabel[strlen(editlabel) - 1] = '\0';
			}
			menuitem = gtk_menu_item_new_with_label(deletelabel);
			g_signal_connect(menuitem, "activate", G_CALLBACK(delete_selected_dives_cb), path);
			gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);

			menuitem = gtk_menu_item_new_with_label(editlabel);
			g_signal_connect(menuitem, "activate", G_CALLBACK(edit_selected_dives_cb), NULL);
			gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
		} else {
			deletelabel[strlen(deletelabel) - 1] = '\0';
			menuitem = gtk_menu_item_new_with_label(deletelabel);
			g_signal_connect(menuitem, "activate", G_CALLBACK(delete_dive_cb), path);
			gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);

			editlabel[strlen(editlabel) - 1] = '\0';
			menuitem = gtk_menu_item_new_with_label(editlabel);
			g_signal_connect(menuitem, "activate", G_CALLBACK(edit_dive_from_path_cb), path);
			gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
		}
		/* only offer trip editing options when we are displaying the tree model */
		if (dive_list.model == dive_list.treemodel) {
			int depth = gtk_tree_path_get_depth(path);
			int *indices = gtk_tree_path_get_indices(path);
			/* top level dive or child dive that is not the first child */
			if (depth == 1 || indices[1] > 0) {
				menuitem = gtk_menu_item_new_with_label("Create new trip above");
				g_signal_connect(menuitem, "activate", G_CALLBACK(insert_trip_before_cb), path);
				gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
			}
			prevpath = gtk_tree_path_copy(path);
			/* top level dive with a trip right before it */
			if (depth == 1 &&
			    gtk_tree_path_prev(prevpath) &&
			    gtk_tree_model_get_iter(MODEL(dive_list), &previter, prevpath) &&
			    gtk_tree_model_iter_n_children(model, &previter)) {
				menuitem = gtk_menu_item_new_with_label("Add to trip above");
				g_signal_connect(menuitem, "activate", G_CALLBACK(merge_dive_into_trip_above_cb), path);
				gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
			}
			if (DIVE_IN_TRIP(dive)) {
				if (dive->selected && amount_selected > 1)
					menuitem = gtk_menu_item_new_with_label("Remove selected dives from trip");
				else
					menuitem = gtk_menu_item_new_with_label("Remove dive from trip");
				g_signal_connect(menuitem, "activate", G_CALLBACK(remove_from_trip_cb), path);
				gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
			}
		}
	}
	menuitem = gtk_menu_item_new_with_label("Expand all");
	g_signal_connect(menuitem, "activate", G_CALLBACK(expand_all_cb), tree_view);
	gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
	menuitem = gtk_menu_item_new_with_label("Collapse all");
	g_signal_connect(menuitem, "activate", G_CALLBACK(collapse_all_cb), tree_view);
	gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
	gtk_widget_show_all(menu);

	gtk_menu_popup(GTK_MENU(menu), NULL, NULL, NULL, NULL,
		button, gtk_get_current_event_time());
}

static void popup_menu_cb(GtkTreeView *tree_view, gpointer userdata)
{
	popup_divelist_menu(tree_view, MODEL(dive_list), 0, NULL);
}

static gboolean button_press_cb(GtkWidget *treeview, GdkEventButton *event, gpointer userdata)
{
	/* Right-click? Bring up the menu */
	if (event->type == GDK_BUTTON_PRESS  &&  event->button == 3) {
		popup_divelist_menu(GTK_TREE_VIEW(treeview), MODEL(dive_list), 3, event);
		return TRUE;
	}
	return FALSE;
}

/* we need to have a temporary copy of the selected dives while
   switching model as the selection_cb function keeps getting called
   when gtk_tree_selection_select_path is called.  We also need to
   keep copies of the sort order so we can restore that as well after
   switching models. */
static gboolean second_call = FALSE;
static GtkSortType sortorder[] = { [0 ... DIVELIST_COLUMNS - 1] = GTK_SORT_DESCENDING, };
static int lastcol = DIVE_DATE;

/* Check if this dive was selected previously and select it again in the new model;
 * This is used after we switch models to maintain consistent selections.
 * We always return FALSE to iterate through all dives */
static gboolean set_selected(GtkTreeModel *model, GtkTreePath *path,
				GtkTreeIter *iter, gpointer data)
{
	GtkTreeSelection *selection = GTK_TREE_SELECTION(data);
	int idx, selected;
	struct dive *dive;

	gtk_tree_model_get(model, iter,
		DIVE_INDEX, &idx,
		-1);
	if (idx < 0) {
		GtkTreeIter child;
		if (gtk_tree_model_iter_children(model, &child, iter))
			gtk_tree_model_get(model, &child, DIVE_INDEX, &idx, -1);
	}
	dive = get_dive(idx);
	selected = dive && dive->selected;
	if (selected) {
		gtk_tree_view_expand_to_path(GTK_TREE_VIEW(dive_list.tree_view), path);
		gtk_tree_selection_select_path(selection, path);
	}
	return FALSE;

}

static void update_column_and_order(int colid)
{
	/* Careful: the index into treecolumns is off by one as we don't have a
	   tree_view column for DIVE_INDEX */
	GtkTreeViewColumn **treecolumns = &dive_list.nr;

	/* this will trigger a second call into sort_column_change_cb,
	   so make sure we don't start an infinite recursion... */
	second_call = TRUE;
	gtk_tree_sortable_set_sort_column_id(GTK_TREE_SORTABLE(dive_list.model), colid, sortorder[colid]);
	gtk_tree_view_column_set_sort_order(treecolumns[colid - 1], sortorder[colid]);
	second_call = FALSE;
}

/* If the sort column is date (default), show the tree model.
   For every other sort column only show the list model.
   If the model changed, inform the new model of the chosen sort column and make
   sure the same dives are still selected.

   The challenge with this function is that once we change the model
   we also need to change the sort column again (as it was changed in
   the other model) and that causes this function to be called
   recursively - so we need to catch that.
*/
static void sort_column_change_cb(GtkTreeSortable *treeview, gpointer data)
{
	int colid;
	GtkSortType order;
	GtkTreeStore *currentmodel = dive_list.model;

	if (second_call)
		return;

	gtk_tree_sortable_get_sort_column_id(treeview, &colid, &order);
	if(colid == lastcol) {
		/* we just changed sort order */
		sortorder[colid] = order;
		return;
	} else {
		lastcol = colid;
	}
	if(colid == DIVE_DATE)
		dive_list.model = dive_list.treemodel;
	else
		dive_list.model = dive_list.listmodel;
	if (dive_list.model != currentmodel) {
		GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));

		gtk_tree_view_set_model(GTK_TREE_VIEW(dive_list.tree_view), MODEL(dive_list));
		update_column_and_order(colid);
		gtk_tree_model_foreach(MODEL(dive_list), set_selected, selection);
	} else {
		if (order != sortorder[colid]) {
			update_column_and_order(colid);
		}
	}
}

GtkWidget *dive_list_create(void)
{
	GtkTreeSelection  *selection;

	dive_list.listmodel = gtk_tree_store_new(DIVELIST_COLUMNS,
				G_TYPE_INT,			/* index */
				G_TYPE_INT,			/* nr */
				G_TYPE_INT64,			/* Date */
				G_TYPE_INT,			/* Star rating */
				G_TYPE_INT, 			/* Depth */
				G_TYPE_INT,			/* Duration */
				G_TYPE_INT,			/* Temperature */
				G_TYPE_INT,			/* Total weight */
				G_TYPE_STRING,			/* Suit */
				G_TYPE_STRING,			/* Cylinder */
				G_TYPE_INT,			/* Nitrox */
				G_TYPE_INT,			/* SAC */
				G_TYPE_INT,			/* OTU */
				G_TYPE_STRING			/* Location */
				);
	dive_list.treemodel = gtk_tree_store_new(DIVELIST_COLUMNS,
				G_TYPE_INT,			/* index */
				G_TYPE_INT,			/* nr */
				G_TYPE_INT64,			/* Date */
				G_TYPE_INT,			/* Star rating */
				G_TYPE_INT, 			/* Depth */
				G_TYPE_INT,			/* Duration */
				G_TYPE_INT,			/* Temperature */
				G_TYPE_INT,			/* Total weight */
				G_TYPE_STRING,			/* Suit */
				G_TYPE_STRING,			/* Cylinder */
				G_TYPE_INT,			/* Nitrox */
				G_TYPE_INT,			/* SAC */
				G_TYPE_INT,			/* OTU */
				G_TYPE_STRING			/* Location */
				);
	dive_list.model = dive_list.treemodel;
	dive_list.tree_view = gtk_tree_view_new_with_model(TREEMODEL(dive_list));
	set_divelist_font(divelist_font);

	selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));

	gtk_tree_selection_set_mode(GTK_TREE_SELECTION(selection), GTK_SELECTION_MULTIPLE);
	gtk_widget_set_size_request(dive_list.tree_view, 200, 200);

	dive_list.nr = divelist_column(&dive_list, dl_column + DIVE_NR);
	dive_list.date = divelist_column(&dive_list, dl_column + DIVE_DATE);
	dive_list.stars = divelist_column(&dive_list, dl_column + DIVE_RATING);
	dive_list.depth = divelist_column(&dive_list, dl_column + DIVE_DEPTH);
	dive_list.duration = divelist_column(&dive_list, dl_column + DIVE_DURATION);
	dive_list.temperature = divelist_column(&dive_list, dl_column + DIVE_TEMPERATURE);
	dive_list.totalweight = divelist_column(&dive_list, dl_column + DIVE_TOTALWEIGHT);
	dive_list.suit = divelist_column(&dive_list, dl_column + DIVE_SUIT);
	dive_list.cylinder = divelist_column(&dive_list, dl_column + DIVE_CYLINDER);
	dive_list.nitrox = divelist_column(&dive_list, dl_column + DIVE_NITROX);
	dive_list.sac = divelist_column(&dive_list, dl_column + DIVE_SAC);
	dive_list.otu = divelist_column(&dive_list, dl_column + DIVE_OTU);
	dive_list.location = divelist_column(&dive_list, dl_column + DIVE_LOCATION);

	fill_dive_list();

	g_object_set(G_OBJECT(dive_list.tree_view), "headers-visible", TRUE,
					  "search-column", DIVE_LOCATION,
					  "rules-hint", TRUE,
					  NULL);

	g_signal_connect_after(dive_list.tree_view, "realize", G_CALLBACK(realize_cb), NULL);
	g_signal_connect(dive_list.tree_view, "row-activated", G_CALLBACK(row_activated_cb), NULL);
	g_signal_connect(dive_list.tree_view, "row-expanded", G_CALLBACK(row_expanded_cb), NULL);
	g_signal_connect(dive_list.tree_view, "row-collapsed", G_CALLBACK(row_collapsed_cb), NULL);
	g_signal_connect(dive_list.tree_view, "button-press-event", G_CALLBACK(button_press_cb), NULL);
	g_signal_connect(dive_list.tree_view, "popup-menu", G_CALLBACK(popup_menu_cb), NULL);
	g_signal_connect(selection, "changed", G_CALLBACK(selection_cb), dive_list.model);
	g_signal_connect(dive_list.listmodel, "sort-column-changed", G_CALLBACK(sort_column_change_cb), NULL);
	g_signal_connect(dive_list.treemodel, "sort-column-changed", G_CALLBACK(sort_column_change_cb), NULL);

	gtk_tree_selection_set_select_function(selection, modify_selection_cb, NULL, NULL);

	dive_list.container_widget = gtk_scrolled_window_new(NULL, NULL);
	gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(dive_list.container_widget),
			       GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
	gtk_container_add(GTK_CONTAINER(dive_list.container_widget), dive_list.tree_view);

	dive_list.changed = 0;

	return dive_list.container_widget;
}

void mark_divelist_changed(int changed)
{
	dive_list.changed = changed;
}

int unsaved_changes()
{
	return dive_list.changed;
}

void remove_autogen_trips()
{
	GtkTreeIter iter;
	GtkTreePath *path;
	timestamp_t when;
	int idx;
	GList *trip;

	/* start with the first top level entry and walk all of them */
	path = gtk_tree_path_new_from_string("0");
	while(gtk_tree_model_get_iter(TREEMODEL(dive_list), &iter, path)) {
		gtk_tree_model_get(TREEMODEL(dive_list), &iter, DIVE_INDEX, &idx, DIVE_DATE, &when, -1);
		if (idx < 0) {
			trip = find_trip(when);
			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;
	}
}