Refactoring: Improve event_loop.

Improve the event loop architecture by making it set the divecomputer in
the constructor - using the same loop for multiple dive computers is not
intended to work.
Also change `next()` in `divemode_loop` to `at()` to make the name more
aligned with its function.

Signed-off-by: Michael Keller <github@ike.ch>

core/dive.cpp

@@ -2554,7 +2554,7 @@ location_t dive::get_gps_location() const
 }
 
 gasmix_loop::gasmix_loop(const struct dive &d, const struct divecomputer &dc) :
-	dive(d), dc(dc), first_run(true), loop("gaschange")
+	dive(d), dc(dc), first_run(true), loop("gaschange", dc)
 {
 }
 
@@ -2571,13 +2571,13 @@ std::pair<int, int> gasmix_loop::next_cylinder_index()
 		return std::make_pair(-1, INT_MAX);
 
 	if (first_run) {
-		next_event = loop.next(dc);
+		next_event = loop.next();
 		last_cylinder_index = 0; // default to first cylinder
 		last_time = 0;
 		if (next_event && ((!dc.samples.empty() && next_event->time.seconds == dc.samples[0].time.seconds) || next_event->time.seconds <= 1)) {
 			last_cylinder_index = dive.get_cylinder_index(*next_event);
 			last_time = next_event->time.seconds;
-			next_event = loop.next(dc);
+			next_event = loop.next();
 		} else if (dc.divemode == CCR) {
 			last_cylinder_index = std::max(get_cylinder_idx_by_use(dive, DILUENT), last_cylinder_index);
 		}
@@ -2587,7 +2587,7 @@ std::pair<int, int> gasmix_loop::next_cylinder_index()
 		if (next_event) {
 			last_cylinder_index = dive.get_cylinder_index(*next_event);
 			last_time = next_event->time.seconds;
-			next_event = loop.next(dc);
+			next_event = loop.next();
 		} else {
 			last_cylinder_index = -1;
 			last_time = INT_MAX;

core/divecomputer.cpp

@@ -200,17 +200,17 @@ void fake_dc(struct divecomputer *dc)
 }
 
 divemode_loop::divemode_loop(const struct divecomputer &dc) :
-	dc(dc), last(dc.divemode), loop("modechange")
+	last(dc.divemode), loop("modechange", dc)
 {
 	/* on first invocation, get first event (if any) */
-	ev = loop.next(dc);
+	ev = loop.next();
 }
 
-divemode_t divemode_loop::next(int time)
+divemode_t divemode_loop::at(int time)
 {
 	while (ev && ev->time.seconds <= time) {
 		last = static_cast<divemode_t>(ev->value);
-		ev = loop.next(dc);
+		ev = loop.next();
 	}
 	return last;
 }

core/divelist.cpp

@@ -433,7 +433,7 @@ static void add_dive_to_deco(struct deco_state *ds, const struct dive &dive, boo
 			int depth = interpolate(psample.depth.mm, sample.depth.mm, j - t0, t1 - t0);
 			auto gasmix = loop.at(j).first;
 			add_segment(ds, dive.depth_to_bar(depth), gasmix, 1, sample.setpoint.mbar,
-				    loop_d.next(j), dive.sac,
+				    loop_d.at(j), dive.sac,
 				    in_planner);
 		}
 	}

core/event.cpp

@@ -81,27 +81,22 @@ enum event_severity event::get_severity() const
 	}
 }
 
-event_loop::event_loop(const char *name) : name(name), idx(0)
+event_loop::event_loop(const char *name, const struct divecomputer &dc) : name(name), idx(0), dc(dc)
 {
 }
 
-struct event *event_loop::next(struct divecomputer &dc)
+const struct event *event_loop::next()
 {
 	if (name.empty())
 		return nullptr;
 	while (idx < dc.events.size()) {
-		struct event &ev = dc.events[idx++];
+		const struct event &ev = dc.events[idx++];
 		if (ev.name == name)
 			return &ev;
 	}
 	return nullptr;
 }
 
-const struct event *event_loop::next(const struct divecomputer &dc)
-{
-	return next(const_cast<divecomputer &>(dc));
-}
-
 struct event *get_first_event(struct divecomputer &dc, const std::string &name)
 {
 	auto it = std::find_if(dc.events.begin(), dc.events.end(), [name](auto &ev) { return ev.name == name; });

core/event.h

@@ -58,10 +58,10 @@ class event_loop
 {
 	std::string name;
 	size_t idx;
+	const struct divecomputer &dc;
 public:
-	event_loop(const char *name);
-	struct event *next(struct divecomputer &dc); // nullptr -> end
-	const struct event *next(const struct divecomputer &dc); // nullptr -> end
+	event_loop(const char *name, const struct divecomputer &dc);
+	const struct event *next(); // nullptr -> end
 };
 
 /* Get gasmixes at increasing timestamps. */
@@ -92,13 +92,13 @@ public:
 
 /* Get divemodes at increasing timestamps. */
 class divemode_loop {
-	const struct divecomputer &dc;
 	divemode_t last;
 	event_loop loop;
 	const struct event *ev;
 public:
 	divemode_loop(const struct divecomputer &dc);
-	divemode_t next(int time);
+	// Return the divemode at a given time during the dive
+	divemode_t at(int time);
 };
 
 extern const struct event *get_first_event(const struct divecomputer &dc, const std::string &name);

core/gaspressures.cpp

@@ -364,7 +364,7 @@ void populate_pressure_information(const struct dive *dive, const struct divecom
 				cyl = sensor;
 		}
 
-		divemode_t dmode = loop_mode.next(time);
+		divemode_t dmode = loop_mode.at(time);
 
 		if (current != std::string::npos) { // calculate pressure-time, taking into account the dive mode for this specific segment.
 			entry.pressure_time = (int)(calc_pressure_time(dive, pi.entry[i - 1], entry) * gasfactor[dmode] + 0.5);

core/planner.cpp

@@ -162,7 +162,7 @@ static int tissue_at_end(struct deco_state *ds, struct dive *dive, const struct
 				ds->max_bottom_ceiling_pressure.mbar = ceiling_pressure.mbar;
 		}
 
-		divemode_t divemode = loop.next(t0.seconds + 1);
+		divemode_t divemode = loop.at(t0.seconds + 1);
 		interpolate_transition(ds, dive, t0, t1, lastdepth, sample.depth, gas, setpoint, divemode);
 		psample = &sample;
 		t0 = t1;
@@ -720,7 +720,7 @@ bool plan(struct deco_state *ds, struct diveplan *diveplan, struct dive *dive, i
 	current_cylinder = get_cylinderid_at_time(dive, dc, sample.time);
 	// Find the divemode at the end of the dive
 	divemode_loop loop(*dc);
-	divemode = loop.next(bottom_time);
+	divemode = loop.at(bottom_time);
 	gas = dive->get_cylinder(current_cylinder)->gasmix;
 
 	po2 = sample.setpoint.mbar;

core/plannernotes.cpp

@@ -595,7 +595,7 @@ void add_plan_to_notes(struct diveplan *diveplan, struct dive *dive, bool show_d
 					std::string temp;
 					struct gasmix gasmix = dive->get_cylinder(dp->cylinderid)->gasmix;
 
-					divemode_t current_divemode = loop.next(dp->time);
+					divemode_t current_divemode = loop.at(dp->time);
 					amb = dive->depth_to_atm(dp->depth.mm);
 					gas_pressures pressures = fill_pressures(amb, gasmix, (current_divemode == OC) ? 0.0 : amb * gasmix.o2.permille / 1000.0, current_divemode);
 

core/profile.cpp

@@ -212,9 +212,9 @@ static void check_setpoint_events(const struct dive *, const struct divecomputer
 	pressure_t setpoint;
 	setpoint.mbar = 0;
 
-	event_loop loop("SP change");
+	event_loop loop("SP change", *dc);
 	bool found = false;
-	while (auto ev = loop.next(*dc)) {
+	while (auto ev = loop.next()) {
 		i = set_setpoint(pi, i, setpoint.mbar, ev->time.seconds);
 		setpoint.mbar = ev->value;
 		found = true;
@@ -876,7 +876,7 @@ static void calculate_deco_information(struct deco_state *ds, const struct deco_
 			int j, t0 = prev.sec, t1 = entry.sec;
 			int time_stepsize = 20, max_ceiling = -1;
 
-			divemode_t current_divemode = loop_d.next(entry.sec);
+			divemode_t current_divemode = loop_d.at(entry.sec);
 			struct gasmix gasmix = loop.at(t1).first;
 			entry.ambpressure = dive->depth_to_bar(entry.depth);
 			entry.gfline = get_gf(ds, entry.ambpressure, dive) * (100.0 - AMB_PERCENTAGE) + AMB_PERCENTAGE;
@@ -1114,7 +1114,7 @@ static void calculate_gas_information_new(const struct dive *dive, const struct
 
 		auto gasmix = loop.at(entry.sec).first;
 		amb_pressure = dive->depth_to_bar(entry.depth);
-		divemode_t current_divemode = loop_d.next(entry.sec);
+		divemode_t current_divemode = loop_d.at(entry.sec);
 		entry.pressures = fill_pressures(amb_pressure, gasmix, (current_divemode == OC) ? 0.0 : entry.o2pressure.mbar / 1000.0, current_divemode);
 		fn2 = 1000.0 * entry.pressures.n2 / amb_pressure;
 		fhe = 1000.0 * entry.pressures.he / amb_pressure;

profile-widget/profilewidget2.cpp

@@ -568,7 +568,7 @@ void ProfileWidget2::contextMenuEvent(QContextMenuEvent *event)
 	m.addAction(tr("Split dive into two"), [this, seconds]() { splitDive(seconds); });
 
 	divemode_loop loop(*d->get_dc(dc));
-	divemode_t divemode = loop.next(seconds);
+	divemode_t divemode = loop.at(seconds);
 	QMenu *changeMode = m.addMenu(tr("Change divemode"));
 	if (divemode != OC)
 		changeMode->addAction(gettextFromC::tr(divemode_text_ui[OC]),

qt-models/diveplannermodel.cpp

@@ -172,7 +172,7 @@ void DivePlannerPointsModel::loadFromDive(dive *dIn, int dcNrIn)
 			if (newtime.seconds - lastrecordedtime.seconds > 10 || cylinderid == get_cylinderid_at_time(d, dc, nexttime)) {
 				if (newtime.seconds == lastrecordedtime.seconds)
 					newtime.seconds += 10;
-				divemode_t current_divemode = loop.next(newtime.seconds - 1);
+				divemode_t current_divemode = loop.at(newtime.seconds - 1);
 				addStop(depthsum / samplecount, newtime.seconds, cylinderid, last_sp.mbar, true, current_divemode);
 				lastrecordedtime = newtime;
 			}
@@ -182,7 +182,7 @@ void DivePlannerPointsModel::loadFromDive(dive *dIn, int dcNrIn)
 		}
 	}
 	// make sure we get the last point right so the duration is correct
-	divemode_t current_divemode = loop.next(dc->duration.seconds);
+	divemode_t current_divemode = loop.at(dc->duration.seconds);
 	if (!hasMarkedSamples && !dc->last_manual_time.seconds)
 		addStop(0, dc->duration.seconds,cylinderid, last_sp.mbar, true, current_divemode);
 	preserved_until = d->duration;