Improve error handling & feedback.

Change default path to minetest.exe on Windows.

.gitignore

@@ -1,2 +1,3 @@
 /target
 **/*.rs.bk
+debug.txt

src/main.rs

@@ -3,15 +3,15 @@ extern crate regex;
 
 use mumble_link::*;
 use regex::Regex;
-use std::io::{BufRead, BufReader};
+use std::io::{BufRead, BufReader, Read, Write};
 use std::process::{Command, Stdio};
 
-fn get_data(captures: &regex::Captures) -> Result<([f32; 3], char, char), String> {
+// Function to convert errors to error strings so we can return that as a result.
-    // Function to convert float parsing errors to error strings so we can return that as a result.
+fn errstr<T>(e: T) -> String where T: ToString {
-    fn errstr(e: std::num::ParseFloatError) -> String {
     e.to_string()
-    }
+}
 
+fn get_data(captures: &regex::Captures) -> Result<([f32; 3], char, char), String> {
     // Get all the named captures.
     Ok(([captures["x"].parse().map_err(errstr)?, captures["y"].parse().map_err(errstr)?, captures["z"].parse().map_err(errstr)?,],
         captures["subject"].chars().next().ok_or("unable to get vec subject")?,
@@ -19,12 +19,38 @@ fn get_data(captures: &regex::Captures) -> Result<([f32; 3], char, char), String
     ))
 }
 
+
 fn main() {
+    match try_main() {
+        Ok(_) => {},
+        Err(err) => {
+            println!("Error: {}", err);
+    
+            // print without a newline and flush to keep the cursor on the same line.
+            print!("Press ENTER to continue...");
+            std::io::stdout().flush().unwrap();
+
+            // Read a single byte and discard.
+            let _ = std::io::stdin().read(&mut [0u8]);
+        }
+    }
+}
+
+fn try_main() -> Result<(), String> {
+    println!("Starting...");
+
     // Hook into Mumble using the very handy crate somebody made.
-    let mut link = MumbleLink::new("Minetest", "Minetest positional audio using a mod and wrapper.").expect("Unable to link to Mumble. Is it running?");
+    let mut link = MumbleLink::new("Minetest", "Minetest positional audio using a mod and wrapper.")
+        .map_err(|e| { format!("Unable to connect to Mumble. Is it running? ({})", e) })?;
+
+    println!("Connected to Mumble successfully.");
 
     // Default command to launch.
-    let mut minetest_command = "/usr/bin/minetest".to_owned();
+    let mut minetest_command = if cfg!(windows) {
+        "C:\\Program Files\\minetest\\bin\\minetest.exe"
+    } else {
+        "/usr/bin/minetest"
+    }.to_owned();
 
     // Look for an argument containing "minetest" to replace default command. (But make sure it isn't this exe because that just leads to crazy recursion...)
     for argument in std::env::args() {
@@ -33,9 +59,11 @@ fn main() {
         }
     }
 
+    println!("Launching Minetest at {}", minetest_command);
+
     let mut child = Command::new(minetest_command)
         .stderr(Stdio::piped()) // We need the output to be piped. For some reason Minetest lua's print function goes to stderr...
-        .spawn().unwrap(); // Spawn the process, panic if it fails.
+        .spawn().map_err(|e| { format!("Unable to start Minetest executable: {}", e) })?; // Spawn the process, return an error if it fails.
 
     // This regex parses lines like "p l [1.0 1.0 1.0]".
     // the first letter (the subject) is either 'p' or 'c' denoting whether this is a player or camera vector.
@@ -51,7 +79,7 @@ fn main() {
     let mut camera = Position::default();
 
     // Run as long as the child proccess is running.
-    while child.try_wait().unwrap().is_none() {
+    while child.try_wait().map_err(errstr)?.is_none() {
         // Get the output from the child process.
         if let Some(ref mut child_output) = child.stderr {
             // Using a BufReader allows us to go through all the lines in a loop.
@@ -106,4 +134,6 @@ fn main() {
             }
         }
     }
+
+    Ok(())
 }