chore(downloads): partial download manager

src-tauri/src/downloads/download_manager.rs

@@ -0,0 +1,40 @@
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+    thread::JoinHandle,
+};
+
+use super::{download_agent::GameDownloadAgent, download_thread_control_flag::DownloadThreadControlFlag};
+
+pub struct DownloadManager {
+    download_agent_registry: HashMap<String, Arc<Mutex<GameDownloadAgent>>>,
+    download_queue: Vec<String>,
+
+    current_thread: Option<JoinHandle<()>>,
+    current_game_id: Option<String>, // Should be the only game download agent in the map with the "Go" flag
+}
+
+impl DownloadManager {
+    pub fn new() -> Self {
+        return Self {
+            download_agent_registry: HashMap::new(),
+            download_queue: Vec::new(),
+            current_thread: None,
+            current_game_id: None,
+        };
+    }
+
+    pub fn queue_game(&mut self, game_id: String, version_name: String) {
+        let existing_da = self.download_agent_registry.get(&game_id);
+
+        if let Some(da_mutex) = existing_da {
+            let da = da_mutex.lock().unwrap();
+            if da.version == version_name {
+                return; // We're already queued
+            }
+
+            da.control_flag.set(DownloadThreadControlFlag::Stop);
+            
+        }
+    }
+}