re-do vga package

vga/src/character.rs

@@ -0,0 +1,64 @@
+#[derive(Copy, Clone, PartialEq, Debug)]
+pub struct Character {
+    character: u8,
+    attribute: u8,
+}
+
+#[derive(Copy, Clone, PartialEq, Debug)]
+pub enum Color {
+    Black = 0x0,
+    Blue = 0x1,
+    Green = 0x2,
+    Cyan = 0x3,
+    Red = 0x4,
+    Magenta = 0x5,
+    Brown = 0x6,
+    Gray = 0x7,
+    DarkGray = 0x8,
+    BrightBlue = 0x9,
+    BrightGreen = 0xA,
+    BrightCyan = 0xB,
+    BrightRed = 0xC,
+    BrightMagenta = 0xD,
+    Yellow = 0xE,
+    White = 0xF,
+}
+
+impl Character {
+    pub fn new(character: u8, foreground: Color, background: Color) -> Character {
+        let attribute = ((background as u8) << 4) + (foreground as u8);
+
+        Character {
+            character,
+            attribute,
+        }
+    }
+
+    pub fn as_bytes(&self) -> (u8, u8) {
+        (self.character, self.attribute)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn creation() {
+        let character = Character::new(b'a', Color::Blue, Color::BrightMagenta);
+
+        assert_eq!(character.character, b'a');
+        assert_eq!(character.attribute, 0xD1);
+
+        let character = Character::new(b'b', Color::Yellow, Color::Red);
+
+        assert_eq!(character.character, b'b');
+        assert_eq!(character.attribute, 0x4E);
+
+        let character = Character::new(b'c', Color::DarkGray, Color::White);
+
+        assert_eq!(character.character, b'c');
+        assert_eq!(character.attribute, 0xF8);
+    }
+
+}