Add methods to convert File and Rank to and from numbers

src/main.rs

@@ -84,7 +84,7 @@ struct Move {
 #[derive(serde::Deserialize, serde::Serialize)]
 #[serde(rename_all = "camelCase")]
 struct Start {
-    player_color: String,
+    player_color: Color,
 }
 
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, serde::Deserialize, serde::Serialize)]
@@ -127,6 +127,35 @@ enum Rank {
     Eight = 8,
 }
 
+impl Rank {
+    fn to_number(&self) -> u8 {
+        match self {
+            Self::One => 0,
+            Self::Two => 1,
+            Self::Three => 2,
+            Self::Four => 3,
+            Self::Five => 4,
+            Self::Six => 5,
+            Self::Seven => 6,
+            Self::Eight => 7,
+        }
+    }
+
+    fn from_number(value: u8) -> Option<Self> {
+        match value {
+            0 => Some(Self::One),
+            1 => Some(Self::Two),
+            2 => Some(Self::Three),
+            3 => Some(Self::Four),
+            4 => Some(Self::Five),
+            5 => Some(Self::Six),
+            6 => Some(Self::Seven),
+            7 => Some(Self::Eight),
+            _ => None,
+        }
+    }
+}
+
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, serde::Deserialize, serde::Serialize)]
 #[serde(rename_all = "camelCase")]
 enum File {
@@ -140,6 +169,35 @@ enum File {
     H,
 }
 
+impl File {
+    fn to_number(&self) -> u8 {
+        match self {
+            Self::A => 0,
+            Self::B => 1,
+            Self::C => 2,
+            Self::D => 3,
+            Self::E => 4,
+            Self::F => 5,
+            Self::G => 6,
+            Self::H => 7,
+        }
+    }
+
+    fn from_number(value: u8) -> Option<Self> {
+        match value {
+            0 => Some(Self::A),
+            1 => Some(Self::B),
+            2 => Some(Self::C),
+            3 => Some(Self::D),
+            4 => Some(Self::E),
+            5 => Some(Self::F),
+            6 => Some(Self::G),
+            7 => Some(Self::H),
+            _ => None,
+        }
+    }
+}
+
 #[derive(Clone, Default)]
 struct FileState {
     inner: HashMap<Rank, Piece>,