[Teton] Terminal now owns the command str.

rust/sys/teton/src/terminal.rs

@@ -1,18 +1,94 @@
+use core::str::Split;
+
 use crate::console::Console;
+use alloc::{
+    format,
+    string::{String, ToString},
+};
 use voyageurs::listener::KeyboardHandler;
 
 pub struct Terminal {
     console: Console,
+    curr_cmd: String,
+    cwd: String,
+    row: u32,
 }
 
 impl KeyboardHandler for Terminal {
     fn handle_char(&mut self, c: char) {
-        self.console.write_char(c)
+        let mut should_execute = false;
+        match c {
+            '\x08' => {
+                let mut chars = self.curr_cmd.chars();
+                chars.next_back(); // Pop last char.
+                self.curr_cmd = chars.collect();
+            }
+            '\n' => should_execute = true,
+            _ => self.curr_cmd.push(c),
+        }
+        self.rewrite_command();
+        if should_execute {
+            self.execute_command();
+            self.rewrite_command();
+        }
     }
 }
 
 impl Terminal {
     pub fn new(console: Console) -> Self {
-        Self { console }
+        let mut term = Self {
+            console,
+            curr_cmd: String::new(),
+            cwd: "/".to_string(),
+            row: 0,
+        };
+        term.rewrite_command();
+        term
+    }
+
+    fn rewrite_command(&mut self) {
+        self.console.write_char('>', self.row, 0);
+
+        let mut col = 1;
+        for c in self.curr_cmd.chars() {
+            self.console.write_char(c, self.row, col);
+            col += 1;
+        }
+
+        // Hacky way to properly backspace.
+        // FIXME: This won't work once we have line wrapping.
+        self.console.write_char(' ', self.row, col)
+    }
+
+    fn write_line(&mut self, line: &str) {
+        let mut col = 0;
+        for c in line.chars() {
+            self.console.write_char(c, self.row, col);
+            col += 1;
+        }
+
+        self.row += 1
+    }
+
+    fn execute_command(&mut self) {
+        self.row += 1;
+
+        let curr_cmd = self.curr_cmd.clone();
+        let mut tokens = curr_cmd.split(' ');
+
+        match tokens.next() {
+            None => {}
+            Some(command) => self.execute_command_parsed(command, tokens),
+        }
+
+        self.curr_cmd.clear()
+    }
+
+    fn execute_command_parsed(&mut self, cmd: &str, _args: Split<'_, char>) {
+        match cmd {
+            "help" => self.write_line("Available commands are 'pwd', 'ls', 'cd', and 'exec'"),
+            "pwd" => self.write_line(&self.cwd.clone()),
+            _ => self.write_line(&format!("Unrecognized command: {}", cmd)),
+        }
     }
 }