merge backend refactoring from main

1 files changed, 40 insertions, 0 deletions

diff --git a/pressure.go b/pressure.go
new file mode 100644
index 0000000..631fd97
--- /dev/null
+++ b/pressure.go
@@ -0,0 +1,40 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+)
+
+type Pressure float32
+
+const (
+	Millibar            Pressure = 100
+	Pascal              Pressure = 1
+	Kilopascal          Pressure = 1_000
+	Bar                 Pressure = 100_000
+	PoundsPerSquareInch Pressure = 6_894.757
+)
+
+var PressureUnits = []string{"mbar", "Pa", "kPa", "bar", "psi"}
+
+func ParsePressureUnit(s string) (Pressure, error) {
+	// Each case corresponds to a value in PressureUnits.
+	switch s {
+	case "mbar":
+		return Millibar, nil
+	case "Pa":
+		return Pascal, nil
+	case "kPa":
+		return Kilopascal, nil
+	case "bar":
+		return Bar, nil
+	case "psi":
+		return PoundsPerSquareInch, nil
+	default:
+		return *new(Pressure), errors.New(fmt.Sprintf("invalid unit: '%s'", s))
+	}
+}
+
+func AtmosphericPressure() Pressure {
+	return 101_325 * Pascal
+}