using bundled version of prism

Backend.py

@@ -14,6 +14,52 @@ import tarfile
 from pathlib import Path
 import shutil
 
+def install_prism():
+    global data_dir
+    if not os.path.exists(os.path.join(data_dir, "prism")):
+        install_java(21)
+        suff = "win.zip"
+        if os.name == "posix":
+            suff = "lin.tar.gz"
+        prism_file = "prism/prism-"+suff
+        ftp = FTP("gitea.piwalker.net")
+        ftp.login()
+        ftp.prot_p()
+        with io.BytesIO() as buff:
+            ftp.retrbinary("RETR "+prism_file, buff.write)
+            buff.seek(0)
+            if os.name == "nt":
+                with zipfile.ZipFile(buff) as zip:
+                    zip.extractall(os.path.join(data_dir, "prism"))
+            else:
+                with tarfile.open(fileobj=buff) as tar:
+                    tar.extractall(os.path.join(data_dir, "prism"))
+        with io.BytesIO() as buff:
+            ftp.retrbinary("RETR prism/prismlauncher.cfg", buff.write)
+            buff.seek(0)
+            with open(os.path.join(data_dir, "prism", "prismlauncher.cfg"), 'wb') as file:
+                file.write(buff.getbuffer())
+        ftp.close()
+        suff = "win"
+        cmd = "java.exe"
+        if os.name == "posix":
+            suff = "lin"
+            cmd = "java"
+        data = []
+        with open(os.path.join(data_dir, "prism", "prismlauncher.cfg"), 'r') as file:
+            data = file.readlines()
+
+        for ind, line in enumerate(data):
+            if line.startswith("JavaPath="):
+                data[ind] = "JavaPath="+data_dir.replace("\\", "/")+"/java/java-21-"+suff+"/bin/"+cmd+"\n"
+        with open(os.path.join(data_dir, "prism", "prismlauncher.cfg"), 'w') as file:
+            file.writelines(data)
+                        
+        
+
+
+            
+
 
 
 def get_tar_members_stripped(tar, n_folders_stripped = 1):
@@ -39,8 +85,7 @@ def unzip(zip, dest):
             with zip.open(file_info, 'r') as src:
                 shutil.copyfileobj(src, dst)
 
-
+def get_java_version(mc_version):
-def install_java(mc_version):
     global data_dir
     tokens = mc_version.split(".")
     java = 8
@@ -53,7 +98,10 @@ def install_java(mc_version):
             java = 17
         else:
             java = 21
+    return java
 
+
+def install_java(java):
     suff = "win"
     ext = ".zip"
     if os.name == "posix":
@@ -78,7 +126,6 @@ def install_java(mc_version):
                     unzip(zip, data_dir+"/java/java-"+str(java)+"-"+suff)
 
 
-    return java
             
 
 
@@ -98,6 +145,13 @@ def perform_installation(instance_name, prism_command, prism_instance_path, pack
 
     Path(data_dir).mkdir(parents=True, exist_ok=True)
     Path(data_dir+"/java").mkdir(parents=True, exist_ok=True)
+    install_prism()
+    if os.name == "nt":
+        prism_command = os.path.join(data_dir, "prism", "prismlauncher.exe")
+    else:
+        prism_command = os.path.join(data_dir, "prism", "PrismLauncher")
+    prism_instance_path = os.path.join(data_dir, "prism", "instances")
+
  
     try:
         ftp = FTP("gitea.piwalker.net")
@@ -148,7 +202,8 @@ def perform_installation(instance_name, prism_command, prism_instance_path, pack
                                 if component["uid"] == "net.minecraft":
                                     mc_version = component["version"]
                                     break;
-                        java = install_java(mc_version)
+                        java = get_java_version(mc_version)
+                        install_java(java)
                         option_path = os.path.join(prism_instance_path, instance_name, "instance.cfg")
                         data = []
                         suff = "win"