from .. import TypeEnum, Environment, Arg, Builtin, evaluate, InterpretPanic
from ..structs import *

STRINGS = Environment()

def interpretConcat(symbol, args, env, ns):
    out = ""
    for arg in args:
        out += arg.value
    return String(out)

string_arg = Arg("arg", TypeEnum.STRING)
STRINGS.register("concat", Builtin("concat", interpretConcat, [string_arg, string_arg], string_arg))

def interpretStrip(symbol, args, env, ns):
    return String(args[0].value.strip())

STRINGS.register("strip", Builtin("strip", interpretStrip, [Arg("filename", TypeEnum.STRING)]))

def interpretSplit(symbol, args, env, ns):
    target = args[0]
    if len(args) == 1:
        return List([String(char) for char in target.value])
    splitter = args[1]
    ret = target.value.split(splitter.value)
    return List([String(r) for r in ret])

STRINGS.register("split", Builtin("split", interpretSplit, [Arg("target", TypeEnum.STRING)], Arg("splitter", TypeEnum.STRING, optional=True)))

def interpretJoin(symbol, args, env, ns):
    lst = args[0]
    target = args[1]
    return String(target.value.join([a.value for a in lst.args]))

join_list_arg = Arg("list", TypeEnum.LIST)
join_string_arg = Arg("joiner", TypeEnum.STRING)
STRINGS.register("join", Builtin("join", interpretJoin, [join_list_arg, join_string_arg]))

def interpretFirstChar(symbol, args, env, ns):
    if len(args[0].value) == 0:
        raise InterpretPanic(symbol, ":string is empty", ev)
    return String(args[0].value[0])

STRINGS.register("first-char", Builtin("first-char", interpretFirstChar, [Arg("string", TypeEnum.STRING)]))

def interpretRestChar(symbol, args, env, ns):
    return String(args[0].value[1:])

STRINGS.register("rest-char", Builtin("rest-char", interpretRestChar, [Arg("string", TypeEnum.STRING)]))