Added ability to read WAD directory

src/utils/helpers.rs

@@ -0,0 +1,43 @@
+use std::{
+    fs::File,
+    io::{self, Read},
+    path::Path,
+};
+
+/// Validates a WAD file to make sure that it is a legitimate file
+///
+/// Parameters:
+/// - path: &str - Path to the WAD to validate
+pub fn validate_wad(path: &str) -> io::Result<bool> {
+    let wad_file = Path::new(path);
+
+    // Check to see if the WAD exists
+    if !(wad_file.exists()) {
+        // Return back false because we didn't pass a valid file
+        return Ok(false);
+    }
+
+    // If the file exists open it and read the first 4 bytes
+    // of the file and see if we get "IWAD" or "PWAD"
+    let mut file = File::open(wad_file)?;
+    let mut magic = [0u8; 4];
+    file.read_exact(&mut magic)?;
+
+    // Now we return based on what we found
+    Ok(magic == *b"IWAD" || magic == *b"PWAD")
+}
+
+pub fn read_ascii(bytes: &[u8]) -> String {
+    std::str::from_utf8(&bytes[..bytes.len()])
+        .unwrap_or("")
+        .trim_end_matches('\0')
+        .to_string()
+}
+
+pub fn read_u32_le(bytes: &[u8]) -> u32 {
+    if bytes.len() < 4 {
+        0
+    } else {
+        u32::from_le_bytes(bytes[..4].try_into().unwrap())
+    }
+}