import os
from antlr4 import *
from ptmlTranslator import ptmlTranslator
from ptmlParser import ptmlParser as Parser
from ptmlLexer import ptmlLexer as Lexer

def load(ptml_path: str, behaviour_lib_path: str):
    """_summary_

    Args:
        ptml_path (str): _description_
        behaviour_lib_path (str): _description_

    Raises:
        FileNotFoundError: _description_
        FileNotFoundError: _description_
    """
    # error handle
    if not os.path.exists(ptml_path):
        raise FileNotFoundError(
            'Given a fault ptml path: {}'.format(ptml_path)
        )
    if not os.path.exists(behaviour_lib_path):
        raise FileNotFoundError(
            'Given a fault behaviour library path: {}'.format(behaviour_lib_path)
        )
    
    # noting fault, go next
    input_stream = FileStream(ptml_path, encoding='utf-8')

    lexer = Lexer(input_stream)
    stream = CommonTokenStream(lexer)
    parser = Parser(stream)
    tree = parser.root()
    
    walker = ParseTreeWalker()
    ptml = ptmlTranslator() # listener mode
    walker.walk(ptml, tree)

    return ptml.bt_root