from parse.line import next_line, skip_whitespace

def parse_dw_const(line):
    dw_const, args = line.split(maxsplit=1)
    assert dw_const == "dw_const", line
    args = args.split(';')[0]
    args = [arg.strip() for arg in args.split(',')]
    assert len(args) == 2, args
    assert (
        args[1].startswith('TEXT_')
        or args[1].startswith('SCRIPT_')
    ), args[1]
    return args

def tokenize_textpointer(lines):
    pointers = []
    while lines:
        lines_next, line = next_line(lines)
        if line is None:
            break
        if line.startswith("def_text_pointers"):
            pass
        elif line.startswith("text_end"):
            pass
        elif line.startswith(";"):
            pass
        elif line.startswith("dw_const"):
            pointer = parse_dw_const(line)
            pointers.append(pointer)
        else:
            assert (
                line is None
                or line.endswith(':')
                or line.startswith("def_trainers")
            ), line
            break
        lines = lines_next

    return lines, pointers

def tokenize_textpointers(lines):
    ix = 0
    # skip lines until _TextPointers is found
    while lines:
        lines, line = next_line(lines)
        if line is None:
            break
        if not line.endswith('_TextPointers:'):
            continue

        name = line[:-1]
        lines, textpointers = tokenize_textpointer(lines)
        return name, textpointers

def tokenize_text_far(lines):
    lines, far = next_line(lines)
    lines, end = next_line(lines)
    simple_far = (
        far is not None
        and end is not None
        and far.split()[0] == 'text_far'
        and end.split()[0] == 'text_end'
    )
    if not simple_far:
        return None
    else:
        _, far_label = far.split()
        assert far_label.startswith('_')
        return far_label

def find_text_far(labels, lines):
    while lines:
        lines, line = next_line(lines)
        if line is None:
            break
        if line.endswith(':') and line[:-1] in labels:
            label = line[:-1]
            text_far = tokenize_text_far(lines)
            if text_far is not None:
                yield label, text_far

def tokenize(lines):
    tokens = tokenize_textpointers(lines)
    if tokens is None:
        return None
    name, textpointers = tokens
    labels_l = [label for label, _ in textpointers]
    labels = set(labels_l)

    # now, resolve text_far
    text_far_l = list(find_text_far(labels, lines))
    text_far_d = dict(text_far_l)
    assert len(text_far_l) == len(text_far_d)
    textpointers_d = dict(
        (v, k) for k, v in textpointers
    )
    return name, (textpointers_d, text_far_d)

def parse(path):
    with open(path) as f:
        original_lines = f.read().split('\n')
        tokens = tokenize(original_lines)
        return tokens

def parse_all(prefix):
    base_path = prefix / 'scripts'
    paths = [p for p in base_path.iterdir()
             # fixme: ViridianMart is weird
             if p.is_file() and 'ViridianMart.asm' not in str(p)]
    return dict(filter(lambda x: x is not None,
                   (parse(path) for path in paths)))