from dataclasses import dataclass

import core.utils
from core.tokenizer import TokenKind, Token
from core.var_ref import VariableRef
from parsers.BaseParser import Node, ParsingError, BaseParserInputParser

DEBUG_COMPILED = True


@dataclass()
class LexerNode(Node):
    start: int  # starting index in the tokens list
    end: int  # ending index in the tokens list
    tokens: list = None  # tokens
    source: str = None  # string representation of what was parsed

    def __post_init__(self):
        if self.source is None:
            self.source = core.utils.get_text_from_tokens(self.tokens)

    def __eq__(self, other):
        if not isinstance(other, LexerNode):
            return False

        return self.start == other.start and \
               self.end == other.end and \
               self.source == other.source and \
               self.tokens == other.tokens

    def fix_source(self, force=True):
        if force or self.source is None:
            self.source = core.utils.get_text_from_tokens(self.tokens)
        return self

    def clone(self):
        pass

    def to_short_str(self):
        raise NotImplementedError

    def get_source_to_parse(self):
        return self.source


class UnrecognizedTokensNode(LexerNode):
    def __init__(self, start, end, tokens):
        super().__init__(start, end, tokens)
        self.is_frozen = False  # TODO: Remove as it seems to now be useless
        self.parenthesis_count = 0

    def freeze(self):
        # TODO: Remove as it seems to now be useless
        self.is_frozen = True

    def reset(self):
        self.start = self.end = -1
        self.tokens.clear()
        self.is_frozen = False
        self.parenthesis_count = 0
        self.source = ""

    def add_token(self, token, pos):
        if self.is_frozen:
            raise Exception("The node is frozen")

        if self.end != -1 and pos == self.end + 2:
            # add the missing whitespace
            p = self.tokens[-1]  # previous token
            self.tokens.append(Token(TokenKind.WHITESPACE, " ", p.index + 1, p.line, p.column + 1))

        self.tokens.append(token)
        self.end = pos
        if self.start == -1:
            self.start = pos

        if token.type == TokenKind.LPAR:
            self.parenthesis_count += 1

        if token.type == TokenKind.RPAR:
            self.parenthesis_count -= 1

        return self

    def pop(self, token_kind):
        if self.is_frozen:
            raise Exception("The node is frozen")

        if len(self.tokens) > 0 and self.tokens[-1].type == token_kind:
            self.tokens.pop()
            if len(self.tokens) == 0:
                self.reset()
            else:
                self.end -= 1

    def has_open_paren(self):
        return self.parenthesis_count > 0

    def not_whitespace(self):
        return not self.is_whitespace()

    def is_whitespace(self):
        for t in self.tokens:
            if t.type not in (TokenKind.WHITESPACE, TokenKind.NEWLINE):
                return False
        return True

    def is_empty(self):
        return len(self.tokens) == 0

    def last_token_type(self):
        if len(self.tokens) == 0:
            return None
        return self.tokens[-1].type

    def __eq__(self, other):
        if not isinstance(other, UnrecognizedTokensNode):
            return False

        return self.start == other.start and \
               self.end == other.end and \
               self.source == other.source

    def __hash__(self):
        return hash((self.start, self.end, self.source))

    def __repr__(self):
        return f"UnrecognizedTokensNode(source='{self.source}', start={self.start}, end={self.end})"

    def clone(self):
        clone = UnrecognizedTokensNode(self.start, self.end, self.tokens[:])
        clone.is_frozen = self.is_frozen
        clone.parenthesis_count = self.parenthesis_count
        return clone

    def to_short_str(self):
        return f"UTN('{self.source}')"


class RuleNode(LexerNode):
    def __init__(self, rule, start, end, tokens=None, source=None):
        super().__init__(start, end, tokens, source)
        self.rule = rule
        self.fix_source(False)

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if not isinstance(other, RuleNode):
            return False

        return self.rule == other.rule and \
               self.start == other.start and \
               self.end == other.end and \
               self.source == other.source

    def __hash__(self):
        return hash((self.rule, self.start, self.end, self.source))

    def __repr__(self):
        return f"RuleNode(rule='{self.rule}', source='{self.source}', start={self.start}, end={self.end})"

    def clone(self):
        return RuleNode(self.rule, self.start, self.end, self.tokens, self.source)

    def to_short_str(self):
        return f'RN({self.rule})'


class ConceptNode(LexerNode):
    """
    Returned by the BnfNodeParser
    It represents a recognized concept
    """

    def __init__(self, concept, start, end, tokens=None, source=None, underlying=None):
        super().__init__(start, end, tokens, source)
        self.concept = concept
        self.underlying = underlying
        self.fix_source(False)

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if not isinstance(other, ConceptNode):
            return False

        return self.concept == other.concept and \
               self.start == other.start and \
               self.end == other.end and \
               self.source == other.source and \
               self.underlying == other.underlying

    def __hash__(self):
        return hash((self.concept, self.start, self.end, self.source, self.underlying))

    def __repr__(self):
        text = f"ConceptNode(concept='{self.concept}', source='{self.source}', start={self.start}, end={self.end}"
        if DEBUG_COMPILED:
            for k, v in self.concept.get_compiled().items():
                text += f", {k}='{v}'"
        return text + ")"

    def clone(self):
        # do we need to clone the concept as well ?
        return ConceptNode(self.concept, self.start, self.end, self.tokens, self.source, self.underlying)

    def as_bag(self):
        """
        Creates a dictionary with the useful properties of the ConceptNode
        see Concept.as_bag() for extra information
        """
        bag = {}
        for k, v in self.__dict__.items():
            bag[k] = v

        # if isinstance(self.concept, Concept):
        #     bag["compiled"] = self.concept.get_compiled()
        return bag

    def to_short_str(self):
        return f'CN({self.concept})'

    def get_concept(self):
        """
        Used when there is a mix of Concept and ConceptNode
        To quickly get the inner concept
        :return:
        """
        return self.concept


class SourceCodeNode(LexerNode):
    """
    Returned when some source code (like Python source code is recognized)
    """

    def __init__(self, start, end, tokens=None, source=None,
                 python_node=None, return_value=None, error_when_parsing=None):
        """

        :param start: start position (index of the first token)
        :param end: end position (index of the last token)
        :param tokens:
        :param source: tokens as string
        :param python_node: PythonNode found (when the SourceCodeNode is validated)
        :param return_value: ReturnValueConcept returned when the source was validated

        When return_value is provided,
        You should have return_value.body.body == node
        """
        super().__init__(start, end, tokens, source)

        self.python_node = python_node  # The PythonNode (or whatever language node) that is found
        self.return_value = return_value  # original result of the parsing
        self.error_when_parsing = error_when_parsing  # if python_node is still None after parsing, it explains why

    def __eq__(self, other):
        if not isinstance(other, SourceCodeNode):
            return False

        return self.python_node == other.python_node and \
               self.start == other.start and \
               self.end == other.end and \
               self.source == other.source

    def __hash__(self):
        return hash((self.start, self.end, self.source))

    def __repr__(self):
        return f"SourceCodeNode(start={self.start}, end={self.end}, source='{self.source}')"

    def to_short_str(self):
        return f"SCN('{self.source}')"

    def get_python_node(self):
        return self.python_node

    def get_source_to_parse(self):
        return self.python_node.source

    def clone(self):
        clone = SourceCodeNode(
            self.start,
            self.end,
            self.tokens,
            self.source,
            self.python_node,
            self.return_value)
        return clone


class SourceCodeWithConceptNode(LexerNode):
    """
    Kind of temporary version for SourceCodeNode
    I know that there is some code,
    I know that there are some concepts
    I just don't want to make the glue yet

    So I push all the nodes into one big bag
    """

    def __init__(self, first_node, last_node, content_nodes=None, has_unrecognized=False):
        super().__init__(9999, -1, None)  # why not sys.maxint ?
        self.first = first_node
        self.last = last_node
        self.nodes = content_nodes or []
        self.has_unrecognized = has_unrecognized
        self._all_nodes = None
        self.fix_all_pos()

        self.python_node = None  # if the source code node is validated against a python parse, here is the PythonNode
        self.return_value = None  # return_value that produced the PythonNode
        self.error_when_parsing = None  # if python_node is still None after parsing, it explains why

    def add_node(self, node):
        self.nodes.append(node)
        self.fix_pos(node)
        self._all_nodes = None

        return self

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if not isinstance(other, SourceCodeWithConceptNode):
            return False

        if self.start != other.start or self.end != other.end:
            return False

        if self.first != other.first:
            return False

        if self.last != other.last:
            return False

        if len(self.nodes) != len(other.nodes):
            return False

        for self_node, other_node in zip(self.nodes, other.nodes):
            if self_node != other_node:
                return False

        # at last
        return True

    def __hash__(self):
        return hash((self.first, self.last, len(self.nodes)))

    def __repr__(self):
        return f"SourceCodeWithConceptNode(start={self.start}, end={self.end}, source='{self.source}')"

    def fix_all_pos(self):
        if self.first is None:  # to ease some unit test where only the python_node is necessary
            return

        for n in [self.first, self.last] + self.nodes:
            self.fix_pos(n)

    def fix_pos(self, node):
        if hasattr(node, "start") and node.start is not None:
            if node.start < self.start:
                self.start = node.start

        if hasattr(node, "end") and node.end is not None:
            if node.end > self.end:
                self.end = node.end
        return self

    def pseudo_fix_source(self):
        """
        pseudo because the code is not that clean !
        :return:
        """
        self.source = self.first.source
        for n in self.nodes:
            self.source += " "
            if hasattr(n, "source"):
                self.source += n.source
            elif hasattr(n, "concept"):
                self.source += str(n.concept)
            else:
                self.source += " unknown"
        self.source += self.last.source
        return self

    def get_all_nodes(self):
        if self._all_nodes:
            return self._all_nodes

        self._all_nodes = [self.first, *self.nodes, self.last]
        return self._all_nodes

    def clone(self):
        nodes = [n.clone() for n in self.nodes]
        clone = SourceCodeWithConceptNode(self.first.clone(), self.last.clone(), nodes, self.has_unrecognized)
        clone.python_node = self.python_node
        clone.return_value = self.return_value
        return clone

    def to_short_str(self):
        return f"SCWC({self.first}" + ", ".join(n.to_short_str for n in self.nodes) + f"{self.last})"

    def get_python_node(self):
        return self.python_node

    def get_source_to_parse(self):
        return self.python_node.source


class VariableNode(LexerNode):
    """
    When trying to parser source code, a reference to a variable is recognized
    Not sure yet if it has to be a lexer node
    """

    def __init__(self, obj, prop, start, end, tokens=None, source=None):
        super().__init__(start, end, tokens, source)
        self.var_ref = VariableRef(obj, prop)

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if not isinstance(other, VariableNode):
            return False

        return self.var_ref == other.var_ref and \
               self.start == other.start and \
               self.end == other.end and \
               self.source == other.source

    def __hash__(self):
        return hash((self.var_ref.obj, self.var_ref.prop, self.start, self.end, self.source))

    def __repr__(self):
        ret = f"VariableNode(obj={self.var_ref.obj}, prop={self.var_ref.prop}, "
        ret += f"start={self.start}, end={self.end}, source='{self.source}')"
        return ret

    def to_short_str(self):
        return f"VN({self.var_ref.obj})" if self.var_ref.prop is None else f"VN({self.var_ref.obj}.{self.var_ref.prop})"

    def clone(self):
        clone = VariableNode(self.var_ref.obj, self.var_ref.prop, self.start, self.end, self.tokens, self.source)
        return clone


@dataclass()
class GrammarErrorNode(ParsingError):
    message: str


@dataclass()
class NoMatchingTokenError(ParsingError):
    pos: int


class BaseNodeParser(BaseParserInputParser):
    """
    Parser that return LexerNode
    """

    def __init__(self, name, priority, **kwargs):
        super().__init__(name, priority, yield_eof=True)

    def init_from_concepts(self, context, concepts, **kwargs):
        """
        Initialize the parser with a list of concepts
        For unit tests convenience
        :param context
        :param concepts
        :return:
        """
        from core.sheerka.services.SheerkaConceptManager import SheerkaConceptManager
        service = context.sheerka.services[SheerkaConceptManager.NAME]
        by_token, by_regex = SheerkaConceptManager.compute_concepts_by_first_item(context, concepts).body

        context.sheerka.om.put(SheerkaConceptManager.CONCEPTS_BY_REGEX_ENTRY,
                               False,
                               {k.serialize(): v for k, v in by_regex.items()})
        compiled = service.compile_concepts_by_first_regex(context, by_regex).body
        service.compiled_concepts_by_regex.clear()
        service.compiled_concepts_by_regex.extend(compiled)

        resolved = SheerkaConceptManager.resolve_concepts_by_first_keyword(context, by_token).body
        context.sheerka.om.put(SheerkaConceptManager.RESOLVED_CONCEPTS_BY_FIRST_KEYWORD_ENTRY,
                               False,
                               resolved)

        return self