Update __main__.py

Added option to select Lua version and fixed compatibility issues with C libraries

src/__main__.py

@@ -1,36 +1,25 @@
 import os
+import lupa
 import argparse
+import importlib
 from .luagram import LuagramClient, Params, Settings, BaseLogger, enums
 
 
-try:
-    import lupa.luajit21 as lupa
+LUA_VERSION = os.getenv('LUAGRAM_LUA_VERSION', '5.1')
 
-except ImportError:
-    try:
-        import lupa.lua54 as lupa
-
-    except ImportError:
-        try:
-            import lupa.lua53 as lupa
-
-        except ImportError:
-            import lupa
+__LUA_VERSIONS = {
+    '5.1': 'lupa.lua51',
+    '5.2': 'lupa.lua52',
+    '5.3': 'lupa.lua53',
+    '5.4': 'lupa.lua54',
+    'jit': 'lupa.luajit21'
+}
 
 
 if not os.path.isdir('.app-data'):
     os.makedirs('.app-data')
 
 
-lua = lupa.LuaRuntime(unpack_returned_tuples=True)
-variables = lua.globals()
-variables.enums = enums
-variables.Params = Params
-variables.Settings = Settings
-variables.BaseLogger = BaseLogger
-variables.create_new_client = LuagramClient
-
-
 def main():
     parser = argparse.ArgumentParser(description='Luagram')
 
@@ -41,13 +30,26 @@ def main():
     parser.add_argument('--script', '-s',
                         help='Path to the Lua script file',
                         type=argparse.FileType('r'), required=True)
+
+    parser.add_argument('--version', '-v',
+                        help='Lua Version', default=LUA_VERSION, choices=__LUA_VERSIONS.keys())
 
-    variables = lua.globals()
+
     arguments = parser.parse_args()
+    with lupa.allow_lua_module_loading():
+        LUA = importlib.import_module(__LUA_VERSIONS[arguments.version])
 
+    lua_runtime = LUA.LuaRuntime(unpack_returned_tuples=True)
+    variables = lua_runtime.globals()
     variables.name = arguments.name
 
-    return lua.execute(arguments.script.read())
+    variables.enums = enums
+    variables.Params = Params
+    variables.Settings = Settings
+    variables.BaseLogger = BaseLogger
+    variables.create_new_client = LuagramClient
+
+    return lua_runtime.execute(arguments.script.read())
 
 
 if __name__ == '__main__':