Introduce recreational planner mode

This adopts the planner to the needs of the recreational diver. Rather than immediately
starting to ascent doing deco stops this mode, this mode stays at the last manually
entered depth for the maximal time before mandantory stops appear (NDL). It does not
change gas but keeps using the last used cylinder.

TODO: * Grey out unused UI elements of the planner in this mode
      * Start ascent before gas runs out (or into reserve)
      * Do a 3min @ 5m safety stop.

Fixes #840

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 66 insertions, 23 deletions

diff --git a/planner.c b/planner.c
index d5852dc7b..60fc31bee 100644
--- a/planner.c
+++ b/planner.c
@@ -800,6 +800,31 @@ int ascend_velocity(int depth, int avg_depth, int bottom_time)
 	}
 }
 
+bool trial_ascent(int trial_depth, int stoplevel, int avg_depth, int bottom_time, double tissue_tolerance, struct gasmix *gasmix, int po2, double surface_pressure)
+{
+
+	bool clear_to_ascend = true;
+	char *trial_cache = NULL;
+
+	cache_deco_state(tissue_tolerance, &trial_cache);
+	while (trial_depth > stoplevel) {
+		int deltad = ascend_velocity(trial_depth, avg_depth, bottom_time) * TIMESTEP;
+		if (deltad > trial_depth) /* don't test against depth above surface */
+			deltad = trial_depth;
+		tissue_tolerance = add_segment(depth_to_mbar(trial_depth, &displayed_dive) / 1000.0,
+					       gasmix,
+					       TIMESTEP, po2, &displayed_dive, prefs.decosac);
+		if (deco_allowed_depth(tissue_tolerance, surface_pressure, &displayed_dive, 1) > trial_depth - deltad) {
+			/* We should have stopped */
+			clear_to_ascend = false;
+			break;
+		}
+		trial_depth -= deltad;
+	}
+	restore_deco_state(trial_cache);
+	return clear_to_ascend;
+}
+
 int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool show_disclaimer)
 {
 	struct sample *sample;
@@ -812,7 +837,6 @@ int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool s
 	struct gaschanges *gaschanges = NULL;
 	int gaschangenr;
 	int *stoplevels = NULL;
-	char *trial_cache = NULL;
 	bool stopping = false;
 	bool clear_to_ascend;
 	int clock, previous_point_time;
@@ -880,6 +904,45 @@ int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool s
 	/* Keep time during the ascend */
 	bottom_time = clock = previous_point_time = displayed_dive.dc.sample[displayed_dive.dc.samples - 1].time.seconds;
 	gi = gaschangenr - 1;
+	if(prefs.recreational_mode) {
+		// How long can we stay at the current depth and still directly ascent to the surface?
+		while (trial_ascent(depth, 0, avg_depth, bottom_time, tissue_tolerance, &displayed_dive.cylinder[current_cylinder].gasmix,
+				  po2, diveplan->surface_pressure / 1000.0)) {
+			tissue_tolerance = add_segment(depth_to_mbar(depth, &displayed_dive) / 1000.0,
+						       &displayed_dive.cylinder[current_cylinder].gasmix,
+						       DECOTIMESTEP, po2, &displayed_dive, prefs.bottomsac);
+			clock += DECOTIMESTEP;
+		}
+		clock -= DECOTIMESTEP;
+		plan_add_segment(diveplan, clock - previous_point_time, depth, gas, po2, false);
+		previous_point_time = clock;
+		do {
+			/* Ascend to surface */
+			int deltad = ascend_velocity(depth, avg_depth, bottom_time) * TIMESTEP;
+			if (ascend_velocity(depth, avg_depth, bottom_time) != last_ascend_rate) {
+				plan_add_segment(diveplan, clock - previous_point_time, depth, gas, po2, false);
+				previous_point_time = clock;
+				last_ascend_rate = ascend_velocity(depth, avg_depth, bottom_time);
+			}
+			if (depth - deltad < 0)
+				deltad = depth;
+
+			tissue_tolerance = add_segment(depth_to_mbar(depth, &displayed_dive) / 1000.0,
+						       &displayed_dive.cylinder[current_cylinder].gasmix,
+						       TIMESTEP, po2, &displayed_dive, prefs.decosac);
+			clock += TIMESTEP;
+			depth -= deltad;
+		} while (depth > 0);
+		plan_add_segment(diveplan, clock - previous_point_time, 0, gas, po2, false);
+		create_dive_from_plan(diveplan, is_planner);
+		add_plan_to_notes(diveplan, &displayed_dive, show_disclaimer, error);
+		fixup_dc_duration(&displayed_dive.dc);
+
+		free(stoplevels);
+		free(gaschanges);
+
+		return(error);
+	}
 
 	if (best_first_ascend_cylinder != current_cylinder) {
 		stopping = true;
@@ -935,28 +998,10 @@ int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool s
 		--stopidx;
 
 		/* Save the current state and try to ascend to the next stopdepth */
-		int trial_depth = depth;
-		cache_deco_state(tissue_tolerance, &trial_cache);
 		while (1) {
 			/* Check if ascending to next stop is clear, go back and wait if we hit the ceiling on the way */
-			clear_to_ascend = true;
-			while (trial_depth > stoplevels[stopidx]) {
-				int deltad = ascend_velocity(trial_depth, avg_depth, bottom_time) * TIMESTEP;
-				if (deltad > trial_depth) /* don't test against depth above surface */
-					deltad = trial_depth;
-				tissue_tolerance = add_segment(depth_to_mbar(trial_depth, &displayed_dive) / 1000.0,
-							       &displayed_dive.cylinder[current_cylinder].gasmix,
-							       TIMESTEP, po2, &displayed_dive, prefs.decosac);
-				if (deco_allowed_depth(tissue_tolerance, diveplan->surface_pressure / 1000.0, &displayed_dive, 1) > trial_depth - deltad) {
-					/* We should have stopped */
-					clear_to_ascend = false;
-					break;
-				}
-				trial_depth -= deltad;
-			}
-			restore_deco_state(trial_cache);
-
-			if (clear_to_ascend)
+			if (trial_ascent(depth, stoplevels[stopidx], avg_depth, bottom_time, tissue_tolerance,
+					 &displayed_dive.cylinder[current_cylinder].gasmix, po2, diveplan->surface_pressure / 1000.0))
 				break; /* We did not hit the ceiling */
 
 			/* Add a minute of deco time and then try again */
@@ -970,7 +1015,6 @@ int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool s
 			tissue_tolerance = add_segment(depth_to_mbar(depth, &displayed_dive) / 1000.0,
 						       &displayed_dive.cylinder[current_cylinder].gasmix,
 						       DECOTIMESTEP, po2, &displayed_dive, prefs.decosac);
-			cache_deco_state(tissue_tolerance, &trial_cache);
 			clock += DECOTIMESTEP;
 			/* Finish infinite deco */
 			if(clock >= 48 * 3600 && depth >= 6000) {
@@ -1002,7 +1046,6 @@ int plan(struct diveplan *diveplan, char **cached_datap, bool is_planner, bool s
 					}
 				}
 			}
-			trial_depth = depth;
 		}
 		if (stopping) {
 			/* Next we will ascend again. Add a waypoint if we have spend deco time */