work on nav command under new model

84_Super_Star_Trek/rust/src/main.rs

@@ -1,21 +1,25 @@
-use std::{io::{stdin, stdout, Write}, process::exit};
+use std::{io::{stdin, stdout, Write}, process::exit, str::FromStr};
 
 use model::Galaxy;
 
+use crate::text_constants::BAD_NAV;
+
 mod model;
 mod commands;
+mod text_constants;
 
 fn main() {
     ctrlc::set_handler(move || { exit(0) })
     .expect("Error setting Ctrl-C handler");
 
-    let galaxy = Galaxy::generate_new();
+    let mut galaxy = Galaxy::generate_new();
     // init ops, starting state and notes
     commands::short_range_scan(&galaxy);
 
     loop {
         match prompt("Command?").as_str() {
             "SRS" => commands::short_range_scan(&galaxy),
+            "NAV" => gather_dir_and_speed_then_move(&mut galaxy),
             _ => print_command_help()
         }
 
@@ -25,11 +29,31 @@ fn main() {
     }
 }
 
-fn prompt(prompt: &str) -> String {
+fn gather_dir_and_speed_then_move(galaxy: &mut Galaxy) {
+    let dir = prompt_value::<u8>("Course (1-9)?", 1, 9);
+    if dir.is_none() {
+        println!("{}", BAD_NAV); 
+        return;
+    }
+
+    let speed = prompt_value::<f32>("Course (1-9)?", 0.0, 8.0);
+    if speed.is_none() {
+        println!("{}", BAD_NAV); 
+        return;
+    }
+
+    let distance = (speed.unwrap() * 8.0) as i32;
+    // could be done with a step function - while distance > 0, move by digit.
+    // if passing a boundary, test for the next quadrant in that direction
+    // if present, change quadrant and move to border
+    // else stop.
+}
+
+fn prompt(prompt_text: &str) -> String {
     let stdin = stdin();
     let mut stdout = stdout();
 
-    print!("{prompt} ");
+    print!("{prompt_text} ");
     let _ = stdout.flush();
 
     let mut buffer = String::new();
@@ -39,11 +63,15 @@ fn prompt(prompt: &str) -> String {
     "".into()
 }
 
+fn prompt_value<T: FromStr + PartialOrd>(prompt_text: &str, min: T, max: T) -> Option<T> {
+    let passed = prompt(prompt_text);
+    match passed.parse::<T>() {
+        Ok(n) if (n >= min && n <= max) => Some(n),
+        _ => None
+    }
+}
+
 fn print_command_help() {
     println!("valid commands are just SRS and NAV at the mo")
 }
 
-// match text.parse::<u8>() {
-//     Ok(n) if (n >= 1 && n <= 8) => Some(Message::DirectionForNav(n)),
-//     _ => None
-// }

84_Super_Star_Trek/rust/src/text_constants.rs

@@ -0,0 +1,2 @@
+
+pub const BAD_NAV: &str = "   Lt. Sulu reports, 'Incorrect course data, sir!'";