import re
from lark import Token

# https://stackoverflow.com/a/1176023/6938271
MIXED_2_SNAKE_CASE = re.compile(r'(?<!^)(?=[A-Z])')

ENUM_EXCLUDE_ALWAYS = [
    'JsonValue'
]

BOXED_TYPES = [
    'RichText',
    'PageBlock'
]

STRUCT_EXCLUDE_ALWAYS = [
    'JsonValueNull',
    'JsonValueBoolean',
    'JsonValueNumber',
    'JsonValueString',
    'JsonValueArray',
    'JsonValueObject'
]

def to_snake_case(ident):
    return MIXED_2_SNAKE_CASE.sub('_', ident).lower()

def to_camel_case(ident):
    if len(ident) == 0:
        return ''
    return ident[0].upper() + ident[1:]

def escape_doc(doc):
    return doc.translate(str.maketrans({"\"": '\\"', "\\": "\\\\"})).replace('\n', '  \\n')

SCALAR_MAPPING = {
    'string': ('String', False),
    'int32': ('i32', False),
    'int53': ('i64', False),
    'int64': ('i64', True),
    'double': ('f64', False),
    'bytes': ('String', False),
    'Bool': ('bool', False),
}

def type_is_scalar(name):
    return name in SCALAR_MAPPING

def convert_scalar_name(name):
    return SCALAR_MAPPING[name]


def parse_param(raw_type) -> tuple: # rusty_name: str, inner: str, deserializer: Optional[int]
    if isinstance(raw_type, Token):
        if type_is_scalar(raw_type):
            scalar, deserialize = convert_scalar_name(raw_type)
            if deserialize:
                return scalar, scalar, 0
            else:
                return scalar, scalar, None
        else:
            rusty_type = to_camel_case(raw_type)
            if rusty_type in BOXED_TYPES:
                return f'Box<{rusty_type}>', rusty_type, None
            return rusty_type, rusty_type, None
    else:
        inner_full, inner_inner, deserializer = parse_param(raw_type.children[0])
        if deserializer is not None:
            deserializer += 1
        return f'Vec<{inner_full}>', inner_inner, deserializer