1 files changed, 114 insertions, 0 deletions
diff --git a/src/values/rotation.rs b/src/values/rotation.rs
new file mode 100755
index 0000000..90e3f84
--- /dev/null
+++ b/src/values/rotation.rs
@@ -0,0 +1,114 @@
+use std::num::ParseFloatError;
+use std::str::FromStr;
+
+use iced::{Radians, Rotation};
+
+use super::Value;
+
+#[derive(Debug, thiserror::Error, Clone, PartialEq)]
+pub enum ParseRotationError {
+    #[error("float parsing error: {0}")]
+    ParseFloatError(ParseFloatError),
+    #[error("invalid prefix")]
+    InvalidPrefix,
+    #[error("cannot parse rotation from empty string")]
+    Empty,
+}
+
+impl From<ParseFloatError> for ParseRotationError {
+    fn from(value: ParseFloatError) -> Self {
+        Self::ParseFloatError(value)
+    }
+}
+
+impl Value for Rotation {
+    type Err = ParseRotationError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s = s.trim();
+
+        if s.is_empty() {
+            return Err(ParseRotationError::Empty);
+        }
+
+        if s.starts_with(|c: char| !c.is_ascii_digit()) {
+            let (prefix, value) = s.split_at(1);
+            match prefix.to_lowercase().as_str() {
+                "s" => Ok(Rotation::Solid(Radians(f32::from_str(value)?))),
+                "f" => Ok(Rotation::Floating(Radians(f32::from_str(value)?))),
+                _ => Err(ParseRotationError::InvalidPrefix),
+            }
+        } else {
+            Ok(Rotation::Floating(Radians(f32::from_str(s)?)))
+        }
+    }
+
+    fn to_string(&self) -> String {
+        match self {
+            Self::Floating(value) => format!("f{}", value),
+            Self::Solid(value) => format!("s{}", value),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn can_parse_without_prefix() {
+        assert_eq!(
+            Rotation::from_str("10.5"),
+            Ok(Rotation::Floating(Radians(10.5)))
+        )
+    }
+
+    #[test]
+    fn can_parse_with_s_prefix() {
+        assert_eq!(
+            Rotation::from_str("  s12.3"),
+            Ok(Rotation::Solid(Radians(12.3)))
+        );
+
+        assert_eq!(
+            Rotation::from_str("S9.4"),
+            Ok(Rotation::Solid(Radians(9.4)))
+        )
+    }
+
+    #[test]
+    fn can_parse_with_f_prefix() {
+        assert_eq!(
+            Rotation::from_str("f16.9"),
+            Ok(Rotation::Floating(Radians(16.9)))
+        );
+
+        assert_eq!(
+            Rotation::from_str("F21.45 "),
+            Ok(Rotation::Floating(Radians(21.45)))
+        )
+    }
+
+    #[test]
+    fn cant_parse_invalid_prefix() {
+        assert_eq!(
+            Rotation::from_str("a6.0"),
+            Err(ParseRotationError::InvalidPrefix)
+        )
+    }
+
+    #[test]
+    fn cant_parse_invalid_float() {
+        assert_eq!(
+            Rotation::from_str("3.a"),
+            Err(ParseRotationError::ParseFloatError(
+                f32::from_str("3.a").expect_err("float parse should fail")
+            ))
+        )
+    }
+
+    #[test]
+    fn cant_parse_empty_string() {
+        assert_eq!(Rotation::from_str(" "), Err(ParseRotationError::Empty))
+    }
+}