Introduce structures for formatting and parsing Duration and Distance values

These aren't in use yet.

fitnesstrax/app/src/types.rs

@@ -100,3 +100,120 @@ impl From<si::Kilogram<f64>> for Weight {
         Self(value)
     }
 }
+
+#[derive(Clone, Copy, Debug, Default, PartialEq, PartialOrd)]
+pub struct Distance {
+    value: si::Meter<f64>,
+}
+
+impl Distance {
+    pub fn format(&self, option: FormatOption) -> String {
+        match option {
+            FormatOption::Abbreviated => format!("{} km", self.value.value_unsafe / 1000.),
+            FormatOption::Full => format!("{} kilometers", self.value.value_unsafe / 1000.),
+        }
+    }
+
+    pub fn parse(s: &str) -> Result<Distance, ParseError> {
+        let digits = take_digits(s.to_owned());
+        let value = digits.parse::<f64>().map_err(|_| ParseError)?;
+        Ok(Distance {
+            value: value * 1000. * si::M,
+        })
+    }
+}
+
+impl std::ops::Add for Distance {
+    type Output = Distance;
+    fn add(self, rside: Self) -> Self::Output {
+        Self::Output::from(self.value + rside.value)
+    }
+}
+
+impl std::ops::Sub for Distance {
+    type Output = Distance;
+    fn sub(self, rside: Self) -> Self::Output {
+        Self::Output::from(self.value - rside.value)
+    }
+}
+
+impl std::ops::Deref for Distance {
+    type Target = si::Meter<f64>;
+    fn deref(&self) -> &Self::Target {
+        &self.value
+    }
+}
+
+impl From<si::Meter<f64>> for Distance {
+    fn from(value: si::Meter<f64>) -> Self {
+        Self { value }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Default, PartialEq, PartialOrd)]
+pub struct Duration {
+    value: si::Second<f64>,
+}
+
+impl Duration {
+    pub fn format(&self, option: FormatOption) -> String {
+        let (hours, minutes) = self.hours_and_minutes();
+        let (h, m) = match option {
+            FormatOption::Abbreviated => ("h", "m"),
+            FormatOption::Full => ("hours", "minutes"),
+        };
+        if hours > 0 {
+            format!("{}{} {}{}", hours, h, minutes, m)
+        } else {
+            format!("{}{}", minutes, m)
+        }
+    }
+
+    pub fn parse(s: &str) -> Result<Duration, ParseError> {
+        let digits = take_digits(s.to_owned());
+        let value = digits.parse::<f64>().map_err(|_| ParseError)?;
+        Ok(Duration {
+            value: value * 60. * si::S,
+        })
+    }
+
+    fn hours_and_minutes(&self) -> (i64, i64) {
+        let minutes: i64 = (self.value.value_unsafe / 60.).round() as i64;
+        let hours: i64 = minutes / 60;
+        let minutes = minutes - (hours * 60);
+        (hours, minutes)
+    }
+}
+
+impl std::ops::Add for Duration {
+    type Output = Duration;
+    fn add(self, rside: Self) -> Self::Output {
+        Self::Output::from(self.value + rside.value)
+    }
+}
+
+impl std::ops::Sub for Duration {
+    type Output = Duration;
+    fn sub(self, rside: Self) -> Self::Output {
+        Self::Output::from(self.value - rside.value)
+    }
+}
+
+impl std::ops::Deref for Duration {
+    type Target = si::Second<f64>;
+    fn deref(&self) -> &Self::Target {
+        &self.value
+    }
+}
+
+impl From<si::Second<f64>> for Duration {
+    fn from(value: si::Second<f64>) -> Self {
+        Self { value }
+    }
+}
+
+fn take_digits(s: String) -> String {
+    s.chars()
+        .take_while(|t| t.is_ascii_digit())
+        .collect::<String>()
+}