from typing import Generic, TypeVar, Callable
from tudelft.utilities.immutablelist.AbstractImmutableList import AbstractImmutableList
from tudelft.utilities.immutablelist.ImmutableList import ImmutableList
from decimal import Decimal
from abc import ABC

OUT=TypeVar("OUT")
IN1=TypeVar("IN1")
IN2=TypeVar("IN2") 

class MapThreadList(AbstractImmutableList[OUT], Generic[OUT, IN1, IN2]): 
	'''
	@param <OUT> output type of function and element type of resulting list
	@param <IN1> fype of first input parameter of function and of elements in
	             first list
	@param <IN2> type of second input parameter of function and of elements in
	             second list

	'''

	def __init__(self, f:Callable[[IN1, IN2], OUT],	list1:ImmutableList[IN1], list2:ImmutableList[IN2]):
		'''
		creates a list [f(a1,b1), f(a2, b2) ,. ..., f(an, bb)].
		
		@param f     a {@link BiFunction}. Note, previously this used Function2
		             which was identical to this function now built into Java.
		@param list1 a list of items [a1,a2,..., an]
		@param list2 a list of items [b1, b2,...,bn] of same length as list1
		'''
		if f == None or list1 == None or list2 == None:
			raise ValueError("null argument")
		if list1.size() != list2.size():
			raise ValueError("lists are unequal size")
		self.__list1 = list1
		self.__list2 = list2
		self.__f = f
	
	def  get(self, index:int) -> OUT:
		return self.__f(self.__list1.get(index), self.__list2.get(index));

	def size(self) -> int:
		return self.__list1.size();