1 files changed, 66 insertions, 0 deletions
diff --git a/2018-tower-defence/src/engine/command.rs b/2018-tower-defence/src/engine/command.rs
new file mode 100644
index 0000000..76cfaee
--- /dev/null
+++ b/2018-tower-defence/src/engine/command.rs
@@ -0,0 +1,66 @@
+use std::fmt;
+use super::constants::*;
+use super::geometry::Point;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Command {
+    Nothing,
+    Build(Point, BuildingType),
+    IronCurtain
+}
+
+impl fmt::Display for Command {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            Command::Nothing => write!(f, ""),
+            Command::Build(p, b) => write!(f, "{},{},{}", p.x(), p.y(), b as u8),
+            Command::IronCurtain => write!(f, "0,0,5")
+        }
+    }
+}
+
+impl Command {
+    pub fn cant_build_yet(self, energy: u16) -> bool {
+        use self::Command::*;
+
+        match self {
+            Nothing => false,
+            Build(_, b) => b.cant_build_yet(energy),
+            IronCurtain => energy < IRON_CURTAIN_PRICE
+        }
+    }
+}
+
+
+#[repr(u8)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BuildingType {
+    Defence = 0,
+    Attack = 1,
+    Energy = 2,
+    Tesla = 4,
+}
+
+impl BuildingType {
+    pub fn all() -> [BuildingType; NUMBER_OF_BUILDING_TYPES] {
+        use self::BuildingType::*;
+        [Defence, Attack, Energy, Tesla]
+    }
+
+    pub fn from_u8(id: u8) -> Option<BuildingType> {
+        use std::mem;
+        if id <= 4 && id != 3 { Some(unsafe { mem::transmute(id) }) } else { None }
+    }
+
+    pub fn cant_build_yet(self, energy: u16) -> bool {
+        use self::BuildingType::*;
+
+        let required = match self {
+            Defence => DEFENCE_PRICE,
+            Attack => MISSILE_PRICE,
+            Energy => ENERGY_PRICE,
+            Tesla => TESLA_PRICE
+        };
+        energy < required
+    }
+}