from xml.etree import ElementTree as ET

from constants import GAZ_VAR_TAG, GAZ_ARG_TAG


class Variable:
    def __init__(self, name: str, type: str, qualifier: str, value: any = None):
        self.name = name
        self.type = type
        self.value = value
        self.qualifier = qualifier
        self.xml = self._build_xml()

    def _build_xml(self):
        args = [
            ('name', self.name),
            ('type', self.type),
            ('mut', self.qualifier),
        ]
        return build_xml_element(args, name=GAZ_VAR_TAG)


class Argument:
    def __init__(self, name: str, type: str):
        self.name = name
        self.type = type
        self.xml = self._build_xml()

    def __str__(self):
        return self.type + " " + self.name

    def _build_xml(self):
        args = [
            ('name', self.name),
            ('type', self.type),
        ]
        return build_xml_element(args, name=GAZ_ARG_TAG)


class Routine:
    def __init__(self, name: str, type: str, return_type: str, args: list[Argument], xml: ET.Element = None):
        self.name = name
        self.type = type
        self.return_type = return_type
        self.arguments = args
        self.xml = xml
        self.xml = xml


class Scope:
    def __init__(self, enclosing_scope, child_scope=None, associated_xml: ET.Element = None):
        self.symbols = {}
        self.enclosing_scope = enclosing_scope
        self.child_scope = child_scope
        self.xml = associated_xml

    def resolve(self, name) -> ET.Element or None:
        if name in self.symbols:
            return self.symbols[name]
        else:
            return None

    def append(self, name, item: Variable or Argument or Routine):
        self.symbols[name] = item

    def append_element(self, name, value: ET.Element):
        self.symbols[name] = value

    def set(self, name, value: ET.Element):
        self.symbols[name] = value

    def get_all_defined_mutable_vars(self) -> list[Variable]:
        if self.enclosing_scope is None:
            return self._get_mutable_vars()
        else:
            return self.enclosing_scope.get_all_defined_mutable_vars() + self._get_mutable_vars()

    def _get_mutable_vars(self) -> list[Variable]:
        mutable_vars = []

        for name, var in self.symbols.items():
            if not isinstance(var, Variable):
                continue
            if var.qualifier != 'const':
                mutable_vars.append(self.symbols[name])
        return mutable_vars

    def get_top_scope(self):
        if self.enclosing_scope is None:
            return self
        else:
            return self.enclosing_scope.get_top_scope()


def build_xml_element(*keys, name):
    elem = ET.Element(name)
    for key in list(keys)[0]:  # TODO refactor
        elem.set(key[0], key[1])
    return elem