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;

/*
 * 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,		/* time_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
};

/* magic numbers that indicate (as negative values) model entries that
 * are summary entries for a divetrip */
#define NEW_TRIP 1

#ifdef DEBUG_MODEL
static gboolean dump_model_entry(GtkTreeModel *model, GtkTreePath *path,
				GtkTreeIter *iter, gpointer data)
{
	char *location;
	int idx, nr, rating, depth;

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_NR, &nr, DIVE_RATING, &rating, DIVE_DEPTH, &depth, DIVE_LOCATION, &location, -1);
	printf("entry #%d : nr %d rating %d depth %d location %s \n", idx, nr, rating, depth, location);
	free(location);

	return FALSE;
}

static void dump_model(GtkListStore *store)
{
	gtk_tree_model_foreach(GTK_TREE_MODEL(store), dump_model_entry, NULL);
}
#endif

static GList *selected_dives;
static int st_size = 0;

gboolean is_in_st(int idx, int *atpos)
{
	int i;

	for (i = 0; i < amount_selected; i++)
		if (selectiontracker[i] == idx) {
			if (atpos)
				*atpos = i;
			return TRUE;
		}
	return FALSE;
}

#if DEBUG_SELECTION_TRACKING
void dump_selection(void)
{
	int i;

	printf("currently selected are ");
	for (i = 0; i < amount_selected; i++)
		printf("%d ", selectiontracker[i]);
	printf("\n");
}
#endif

void track_select(int idx)
{
	if (idx < 0)
		return;

#if DEBUG_SELECTION_TRACKING
	printf("add %d to selection of %d entries\n", idx, amount_selected);
#endif
	if (is_in_st(idx, NULL))
		return;
	if (amount_selected >= st_size) {
		selectiontracker = realloc(selectiontracker, dive_table.nr * sizeof(int));
		st_size = dive_table.nr;
	}
	selectiontracker[amount_selected] = idx;
	amount_selected++;
	if (amount_selected == 1)
		selected_dive = idx;
#if DEBUG_SELECTION_TRACKING
	printf("increased amount_selected to %d\n", amount_selected);
	dump_selection();
#endif
}

void track_unselect(int idx)
{
	if (idx < 0)
		return;

#if DEBUG_SELECTION_TRACKING
	printf("remove %d from selection of %d entries\n", idx, amount_selected);
#endif
	int atpos;

	if (! is_in_st(idx, &atpos))
		return;
	memmove(selectiontracker + atpos,
		selectiontracker + atpos + 1,
		(amount_selected - atpos - 1) * sizeof(int));
	amount_selected--;
#if DEBUG_SELECTION_TRACKING
	printf("removed %d at pos %d and decreased amount_selected to %d\n", idx, atpos, amount_selected);
	dump_selection();
#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(GTK_TREE_MODEL(model), iter, DIVE_INDEX, diveidx, -1);
		track_select(*diveidx);
	}
}

/* if we click on a summary dive, we actually want to select / unselect
   all the dives "below" it */
static void select_children(GtkTreeModel *model, GtkTreeSelection * selection,
			GtkTreeIter *iter, gboolean was_selected)
{
	int i, nr_children;
	gboolean unexpand = FALSE;
	GtkTreeIter parent;
	GtkTreePath *tpath;

	memcpy(&parent, iter, sizeof(parent));

	tpath = gtk_tree_model_get_path(model, &parent);

	/* stupid gtk doesn't allow us to select rows that are invisible; so if the
	   user clicks on a row that isn't expanded, we briefly expand it, select the
	   children, and then unexpand it again */
	if(!gtk_tree_view_row_expanded(GTK_TREE_VIEW(dive_list.tree_view), tpath)) {
		unexpand = TRUE;
		gtk_tree_view_expand_row(GTK_TREE_VIEW(dive_list.tree_view), tpath, FALSE);
	}
	nr_children = gtk_tree_model_iter_n_children(model, &parent);
	for (i = 0; i < nr_children; i++) {
		gtk_tree_model_iter_nth_child(model, iter, &parent, i);
		if (was_selected)
			gtk_tree_selection_unselect_iter(selection, iter);
		else
			gtk_tree_selection_select_iter(selection, iter);
	}
	if (unexpand)
		gtk_tree_view_collapse_row(GTK_TREE_VIEW(dive_list.tree_view), tpath);
}

/* 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)
{
	GtkTreeSelection *selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(dive_list.tree_view));

	if (gtk_tree_selection_path_is_selected(selection, path))
		select_children(GTK_TREE_MODEL(dive_list.model), selection, iter, FALSE);
}

/* this is called _before_ the selection is changed, for every single entry;
 * we simply have it call down the tree to make sure that summary items toggle
 * their children */
gboolean modify_selection_cb(GtkTreeSelection *selection, GtkTreeModel *model,
			GtkTreePath *path, gboolean was_selected, gpointer userdata)
{
	GtkTreeIter iter;
	int dive_idx;

	if (gtk_tree_model_get_iter(model, &iter, path)) {
		gtk_tree_model_get(model, &iter, DIVE_INDEX, &dive_idx, -1);
		/* turns out we need to move the selectiontracker here */
		if (was_selected)
			track_unselect(dive_idx);
		else
			track_select(dive_idx);
		if (dive_idx < 0) {
			select_children(model, selection, &iter, was_selected);
		}
	}
	/* allow this selection to proceed */
	return TRUE;
}

/* this is called when gtk thinks that the selection has changed */
static void selection_cb(GtkTreeSelection *selection, gpointer userdata)
{
	process_selected_dives(selected_dives, selectiontracker, GTK_TREE_MODEL(dive_list.model));
	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 val, idx;
	struct tm *tm;
	time_t when;
	char buffer[40];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_DATE, &val, -1);

	/* 2038 problem */
	when = val;

	tm = gmtime(&when);
	switch(idx) {
	case -NEW_TRIP:
		snprintf(buffer, sizeof(buffer),
			"Trip %s, %s %d, %d",
			weekday(tm->tm_wday),
			monthname(tm->tm_mon),
			tm->tm_mday, tm->tm_year + 1900);
		break;
	default:
		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];

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, DIVE_NR, &nr, -1);
	if (idx < 0)
		*buffer = '\0';
	else
		snprintf(buffer, sizeof(buffer), "%d", nr);
	g_object_set(renderer, "text", 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;
	GtkTreeStore *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 == GTK_TREE_MODEL(dive_list.treemodel))
		othermodel = dive_list.listmodel;
	else
		othermodel = dive_list.treemodel;
	if (othermodel != dive_list.model)
		/* recursive call */
		gtk_tree_model_foreach(GTK_TREE_MODEL(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 = GTK_TREE_MODEL(dive_list.model);

	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 = GTK_TREE_MODEL(dive_list.model);

	(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;
}

/* random heuristic - not diving in three days implies new dive trip */
#define TRIP_THRESHOLD 3600*24*3
static int new_group(struct dive *dive, struct dive **last_dive, time_t *tm_date)
{
	if (!last_dive)
		return TRUE;
	if (*last_dive) {
		struct dive *ldive = *last_dive;
		if (abs(dive->when - ldive->when) < TRIP_THRESHOLD) {
			*last_dive = dive;
			return FALSE;
		}
	}
	*last_dive = dive;
	if (tm_date) {
		struct tm *tm1 = gmtime(&dive->when);
		tm1->tm_sec = 0;
		tm1->tm_min = 0;
		tm1->tm_hour = 0;
		*tm_date = mktime(tm1);
	}
	return TRUE;
}

static void fill_dive_list(void)
{
	int i;
	GtkTreeIter iter, parent_iter;
	GtkTreeStore *liststore, *treestore;
	struct dive *last_dive = NULL;
	struct dive *first_trip_dive = NULL;
	struct dive *last_trip_dive = NULL;
	time_t dive_date;

	treestore = GTK_TREE_STORE(dive_list.treemodel);
	liststore = GTK_TREE_STORE(dive_list.listmodel);

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

		if (new_group(dive, &last_dive, &dive_date))
		{
			/* make sure we display the first date of the trip in previous summary */
			if (first_trip_dive && last_trip_dive && last_trip_dive->when < first_trip_dive->when)
				gtk_tree_store_set(treestore, &parent_iter,
						DIVE_DATE, last_trip_dive->when,
						DIVE_LOCATION, last_trip_dive->location,
						-1);
			first_trip_dive = dive;

			gtk_tree_store_append(treestore, &parent_iter, NULL);
			gtk_tree_store_set(treestore, &parent_iter,
					DIVE_INDEX, -NEW_TRIP,
					DIVE_NR, -NEW_TRIP,
					DIVE_DATE, dive_date,
					DIVE_LOCATION, dive->location,
					DIVE_TEMPERATURE, 0,
					DIVE_SAC, 0,
					-1);
		}
		last_trip_dive = dive;
		update_cylinder_related_info(dive);
		gtk_tree_store_append(treestore, &iter, &parent_iter);
		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);
	}

	update_dive_list_units();
	if (gtk_tree_model_get_iter_first(GTK_TREE_MODEL(dive_list.model), &iter)) {
		GtkTreeSelection *selection;

		/* select the last dive (and make sure it's an actual dive that is selected) */
		gtk_tree_model_get(GTK_TREE_MODEL(dive_list.model), &iter, DIVE_INDEX, &selected_dive, -1);
		first_leaf(GTK_TREE_MODEL(dive_list.model), &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(GTK_TREE_STORE(dive_list.treemodel));
	gtk_tree_store_clear(GTK_TREE_STORE(dive_list.listmodel));
	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);
}

static void row_activated_cb(GtkTreeView *tree_view,
			GtkTreePath *path,
			GtkTreeViewColumn *column,
			gpointer userdata)
{
	int index;
	GtkTreeIter iter;

	if (!gtk_tree_model_get_iter(GTK_TREE_MODEL(dive_list.model), &iter, path))
		return;
	gtk_tree_model_get(GTK_TREE_MODEL(dive_list.model), &iter, DIVE_INDEX, &index, -1);
	/* a negative index is special for the "group by date" entries */
	if (index >= 0)
		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_dive_cb(GtkWidget *menuitem, gpointer data)
{
	edit_multi_dive_info(amount_selected, selectiontracker);
}

static void popup_divelist_menu(GtkTreeView *tree_view, GtkTreeModel *model, int button)
{
	GtkWidget *menu, *menuitem;
	char editlabel[] = "Edit dives";

	menu = gtk_menu_new();
	menuitem = gtk_menu_item_new_with_label("Add dive");
	g_signal_connect(menuitem, "activate", G_CALLBACK(add_dive_cb), NULL);
	gtk_menu_shell_append(GTK_MENU_SHELL(menu), menuitem);
	if (amount_selected) {
		if (amount_selected == 1)
			editlabel[strlen(editlabel) - 1] = '\0';
		menuitem = gtk_menu_item_new_with_label(editlabel);
		g_signal_connect(menuitem, "activate", G_CALLBACK(edit_dive_cb), model);
		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, GTK_TREE_MODEL(dive_list.model), 0);
}

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), GTK_TREE_MODEL(dive_list.model), 3);
		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 int *oldselection;
static int old_nr_selected;
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 select_selected(GtkTreeModel *model, GtkTreePath *path,
				GtkTreeIter *iter, gpointer data)
{
	int i, idx;
	GtkTreeSelection *selection = GTK_TREE_SELECTION(data);

	gtk_tree_model_get(model, iter, DIVE_INDEX, &idx, -1);
	for (i = 0; i < old_nr_selected; i++)
		if (oldselection[i] == idx) {
			gtk_tree_view_expand_to_path(GTK_TREE_VIEW(dive_list.tree_view), path);
			gtk_tree_selection_select_path(selection, path);

			return FALSE;
		}
	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));

		/* remember what is currently selected, switch models and reselect the selected rows */
		old_nr_selected = amount_selected;
		oldselection = malloc(old_nr_selected * sizeof(int));
		if (amount_selected)
			memcpy(oldselection, selectiontracker, amount_selected * sizeof(int));
		gtk_tree_view_set_model(GTK_TREE_VIEW(dive_list.tree_view), GTK_TREE_MODEL(dive_list.model));

		update_column_and_order(colid);

		if (old_nr_selected) {
			/* we need to select all the dives that were selected */
			/* this is fundamentally an n^2 algorithm as implemented - YUCK */
			gtk_tree_model_foreach(GTK_TREE_MODEL(dive_list.model), select_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_INT,			/* 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_INT,			/* 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(GTK_TREE_MODEL(dive_list.model));
	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, "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), NULL);
	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;
}