diff --git a/FCLauncher/src-tauri/src/modpack.rs b/FCLauncher/src-tauri/src/modpack.rs
index fa16de2..4fd27e0 100644
--- a/FCLauncher/src-tauri/src/modpack.rs
+++ b/FCLauncher/src-tauri/src/modpack.rs
@@ -1,11 +1,12 @@
 
-use crate::ftp;
-use crate::system_dirs::{get_local_data_directory, get_prism_executable};
-use std::env;
+use crate::{ftp, java};
+use crate::system_dirs::{get_data_directory, get_java_executable, get_local_data_directory, get_prism_executable};
+use std::time::Duration;
+use std::{env, thread};
 use std::fs::File;
 use std::process::Command;
 use std::{io::Cursor, path::PathBuf};
-use std::io::{Read, Seek};
+use std::io::{Read, Seek, Write};
 use serde_json::Value;
 use serde::Serialize;
 use serde::Deserialize;
@@ -66,14 +67,61 @@ pub fn launch_modpack(id: String){
         install_modpack(id.clone());
     }
     // Launch
+    let mut child = Command::new(get_local_data_directory().join("prism").join(get_prism_executable())).arg("-l").arg(get_modpack_name(id)).spawn().unwrap();
 }
 
 fn install_modpack(id: String){
     let versions = get_versions(id.clone());
     let path = env::temp_dir().join(format!("{}.mrpack", get_modpack_name(id.clone())));
     let mut file = File::create(path.clone()).unwrap();
-    ftp::ftp_retr(PathBuf::new().join(id).join(versions[versions.len()-1].version.clone()), file, |_| return);
-    let child = Command::new(get_local_data_directory().join("prism").join(get_prism_executable())).arg("-I").arg(path).spawn().unwrap();
+    let ftp_path = PathBuf::new().join(id.clone()).join(versions[versions.len()-1].file.clone().as_str());
+    println!("Downloading file {}", ftp_path.to_str().unwrap());
+    ftp::ftp_retr(ftp_path, &mut file, |_| return).unwrap();
+    let mut child = Command::new(get_local_data_directory().join("prism").join(get_prism_executable())).arg("-I").arg(path).spawn().unwrap();
+    loop {
+        let version_path = get_data_directory().join("prism").join("instances").join(get_modpack_name(id.clone())).join(".minecraft").join("version.txt");
+        if version_path.clone().exists() {
+            let mut ver_file = File::open(version_path).unwrap();
+            let mut buf = String::new();
+            ver_file.read_to_string(&mut buf).unwrap();
+            if buf == versions[versions.len()-1].version.clone().as_str() {
+                break;
+            }
+        }
+        thread::sleep(Duration::from_secs(3));
+    }
+    thread::sleep(Duration::from_secs(1));
+    child.kill();
+    let info_path = get_local_data_directory().join("prism").join("instances").join(get_modpack_name(id.clone())).join("mmc-pack.json");
+    let mut info_file = File::open(info_path.clone()).unwrap();
+    let info_json: Value = serde_json::from_reader(info_file).unwrap();
+    let mut mc_version = "0.0";
+    for component in info_json["components"].as_array().unwrap() {
+        if component["uid"] == "net.minecraft" {
+            mc_version = component["version"].as_str().unwrap();
+        }
+    }
+    java::install_java(get_java_version(mc_version));
+
+    let option_path = get_local_data_directory().join("prism").join("instances").join(get_modpack_name(id.clone())).join("instance.cfg");
+    let mut option_file = File::open(option_path.clone()).unwrap();
+    let mut buf = String::new();
+    option_file.read_to_string(&mut buf);
+    let mut option_file = File::create(option_path).unwrap();
+    let mut set = false;
+    for line in buf.lines() {
+        if line.starts_with("JavaPath=") {
+            option_file.write_all(format!("JavaPath={}/java/java-{}/bin/{}\n", get_data_directory().join("java").into_os_string().to_str().unwrap().replace("\\", "/"), if env::consts::OS == "windows" {"win"} else {"lin"}, get_java_executable()).as_bytes());
+            set = true;
+        } else {
+            option_file.write_all(format!("{}\n",line).as_bytes());
+        }
+    }
+    if !set {
+        option_file.write_all(format!("JavaPath={}/java/java-{}/bin/{}\n", get_data_directory().join("java").into_os_string().to_str().unwrap().replace("\\", "/"), if env::consts::OS == "windows" {"win"} else {"lin"}, get_java_executable()).as_bytes());
+        option_file.write_all("OverrideJavaLocation=true\n".as_bytes());
+        option_file.write_all("OverrideJava=true\n".as_bytes());
+    }
 
 }
 
@@ -102,7 +150,24 @@ fn get_versions(id: String) -> Vec<VersionEntry> {
     buf.rewind();
     let v: Value = serde_json::from_reader(buf).unwrap();
     for version in v.as_array().unwrap() {
-        versions.push(VersionEntry{version: version["Version"].to_string(), file: version["File"].to_string(), date: version["Date"].to_string()});
+        versions.push(VersionEntry{version: version["Version"].as_str().unwrap().to_string(), file: version["File"].as_str().unwrap().to_string(), date: version["Date"].as_str().unwrap().to_string()});
     }
     return versions.clone();
 }
+
+fn get_java_version(mc_version: &str) -> u8{
+    let components: Vec<&str> = mc_version.split(".").collect();
+    let mut java = 8;
+    if components[1] == "17" {
+        java = 17
+    } else if components[1] == "18" || components[1] == "19" {
+        java = 17
+    } else if components[1].parse::<i32>().unwrap() > 19 {
+        if components[1] == "20" && components[1].parse::<i32>().unwrap() < 5 {
+            java = 17
+        } else {
+            java = 21
+        }
+    }
+    return java;
+}