core: add notion of gas-type to core/gas.c

Create a gastype enum, which describes the type of a gas.
For now: air, nitrox, normoxic, trimix and oxygen.

This probably should be made configurable.

The gas types will be used to bin gasses in the statistics
module.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

2 files changed, 42 insertions, 0 deletions

diff --git a/core/gas.c b/core/gas.c
index 128305e12..d37b614fb 100644
--- a/core/gas.c
+++ b/core/gas.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "gas.h"
 #include "pref.h"
+#include "gettext.h"
 #include <stdio.h>
 #include <string.h>
 
@@ -139,3 +140,32 @@ void fill_pressures(struct gas_pressures *pressures, const double amb_pressure,
 		}
 	}
 }
+
+enum gastype gasmix_to_type(struct gasmix mix)
+{
+	if (gasmix_is_air(mix))
+		return GASTYPE_AIR;
+	if (mix.o2.permille >= 980)
+		return GASTYPE_OXYGEN;
+	if (mix.he.permille == 0)
+		return mix.o2.permille >= 230 ? GASTYPE_NITROX : GASTYPE_AIR;
+	if (mix.o2.permille <= 180)
+		return GASTYPE_HYPOXIC_TRIMIX;
+	return mix.o2.permille <= 230 ? GASTYPE_NORMOXIC_TRIMIX : GASTYPE_HYPEROXIC_TRIMIX;
+}
+
+static const char *gastype_names[] = {
+	QT_TRANSLATE_NOOP("gettextFromC", "Air"),
+	QT_TRANSLATE_NOOP("gettextFromC", "Nitrox"),
+	QT_TRANSLATE_NOOP("gettextFromC", "Hypoxic Trimix"),
+	QT_TRANSLATE_NOOP("gettextFromC", "Normoxic Trimix"),
+	QT_TRANSLATE_NOOP("gettextFromC", "Hyperoxic Trimix"),
+	QT_TRANSLATE_NOOP("gettextFromC", "Oxygen")
+};
+
+const char *gastype_name(enum gastype type)
+{
+	if (type < 0 || type >= GASTYPE_COUNT)
+		return "";
+	return translate("gettextFromC", gastype_names[type]);
+}
diff --git a/core/gas.h b/core/gas.h
index 014eaca4b..5e0f4675f 100644
--- a/core/gas.h
+++ b/core/gas.h
@@ -22,6 +22,16 @@ struct gasmix {
 static const struct gasmix gasmix_invalid = { { -1 }, { -1 } };
 static const struct gasmix gasmix_air = { { 0 }, { 0 } };
 
+enum gastype {
+	GASTYPE_AIR,
+	GASTYPE_NITROX,
+	GASTYPE_HYPOXIC_TRIMIX,
+	GASTYPE_NORMOXIC_TRIMIX,
+	GASTYPE_HYPEROXIC_TRIMIX,
+	GASTYPE_OXYGEN,
+	GASTYPE_COUNT
+};
+
 struct icd_data { // This structure provides communication between function isobaric_counterdiffusion() and the calling software.
 	int dN2;      // The change in fraction (permille) of nitrogen during the change
 	int dHe;      // The change in fraction (permille) of helium during the change
@@ -59,6 +69,8 @@ extern fraction_t get_gas_component_fraction(struct gasmix mix, enum gas_compone
 extern void fill_pressures(struct gas_pressures *pressures, double amb_pressure, struct gasmix mix, double po2, enum divemode_t dctype);
 
 extern bool gasmix_is_air(struct gasmix gasmix);
+extern enum gastype gasmix_to_type(struct gasmix mix);
+extern const char *gastype_name(enum gastype type);
 
 #ifdef __cplusplus
 }