from tokens import *
import sys
from collections import namedtuple

FuncImpl = namedtuple("FuncImpl", ("func", "impl"))

STD = {}

def std_exit(status=0):
    sys.exit(status)
    return NebLiteral(NebType.BOOL, True)

def std_print(arg):
    print(arg.value)
    #return []  # TODO this should return empty list
    return NebLiteral(NebType.BOOL, True)

def std_add(arg1, arg2):
    typ = NebType.INT
    if NebType.FLOAT in (arg1.type_, arg2.type_):
        typ = NebType.FLOAT
    return NebLiteral(typ, arg1.value + arg2.value)

def build_sig_dict(*args):
    return {arg.func.in_sig(): arg for arg in args}

def build_std():
    print_string = FuncImpl(NebFunction("print", [NebType.STRING], NebType.BOOL), std_print)
    STD["print"] = build_sig_dict(print_string)

    exit_ = FuncImpl(NebFunction("exit", [], NebType.BOOL), std_exit)
    exit_int = FuncImpl(NebFunction("exit", [NebType.INT], NebType.BOOL), std_exit)
    STD["exit"] = build_sig_dict(exit_, exit_int)

    # arithmetic
    add_int_int = FuncImpl(NebFunction("+", [NebType.INT, NebType.INT], NebType.INT), std_add)
    add_int_float = FuncImpl(NebFunction("+", [NebType.INT, NebType.FLOAT], NebType.FLOAT), std_add)
    add_float_int = FuncImpl(NebFunction("+", [NebType.FLOAT, NebType.INT], NebType.FLOAT), std_add)
    add_float_float = FuncImpl(NebFunction("+", [NebType.FLOAT, NebType.FLOAT], NebType.FLOAT), std_add)
    STD["+"] = build_sig_dict(add_int_int, add_int_float, add_float_int, add_float_float)
    
build_std()