Ability to load masterdata from a folder

src/runtime.rs

@@ -1,10 +1,14 @@
 use lazy_static::lazy_static;
-use std::sync::RwLock;
+use std::collections::HashSet;
+use std::path::Path;
+use std::sync::{Mutex, RwLock};
 use std::fs;
 
 lazy_static! {
     static ref RUNNING: RwLock<bool> = RwLock::new(false);
     static ref DATAPATH: RwLock<String> = RwLock::new(String::new());
+    static ref MASTERDATA_PATH: RwLock<String> = RwLock::new(String::new());
+    static ref MASTERDATA_WARNED: Mutex<HashSet<String>> = Mutex::new(HashSet::new());
     static ref EASTER: RwLock<bool> = RwLock::new(false);
 }
 
@@ -33,6 +37,39 @@ pub fn update_data_path(path: &str) {
     *w = path.to_string();
 }
 
+pub fn update_masterdata_path(path: &str) {
+    let trimmed = path.trim_end_matches('/').to_string();
+    let mut w = MASTERDATA_PATH.write().unwrap();
+    if trimmed.is_empty() {
+        *w = String::new();
+        return;
+    }
+    if !Path::new(&trimmed).is_dir() {
+        println!("Couldn't find masterdata directory {}", trimmed);
+        *w = String::new();
+        return;
+    }
+    *w = trimmed;
+}
+
+pub fn read_masterdata_file(rel_path: &str) -> Option<Vec<u8>> {
+    let base = MASTERDATA_PATH.read().unwrap().clone();
+    if base.is_empty() {
+        return None;
+    }
+    let full_path = format!("{}/{}", base, rel_path);
+    match fs::read(&full_path) {
+        Ok(bytes) => Some(bytes),
+        Err(_) => {
+            let mut warned = MASTERDATA_WARNED.lock().unwrap();
+            if warned.insert(rel_path.to_string()) {
+                println!("Couldn't find masterdata {}", rel_path);
+            }
+            None
+        }
+    }
+}
+
 // Only currently editable by the android so
 pub fn set_easter_mode(enabled: bool) {
     let mut w = EASTER.write().unwrap();