# Abstract classes.


class Event(object):
    def __init__(self, start_mark=None, end_mark=None):
        self.start_mark = start_mark
        self.end_mark = end_mark

    def __repr__(self):
        attributes = [key for key in ["anchor", "tag", "implicit", "value"] if hasattr(self, key)]
        arguments = ", ".join(["%s=%r" % (key, getattr(self, key)) for key in attributes])
        return "%s(%s)" % (self.__class__.__name__, arguments)


class NodeEvent(Event):
    def __init__(self, anchor, start_mark=None, end_mark=None):
        self.anchor = anchor
        self.start_mark = start_mark
        self.end_mark = end_mark


class CollectionStartEvent(NodeEvent):
    def __init__(self, anchor, tag, implicit, start_mark=None, end_mark=None, flow_style=None):
        self.anchor = anchor
        self.tag = tag
        self.implicit = implicit
        self.start_mark = start_mark
        self.end_mark = end_mark
        self.flow_style = flow_style


class CollectionEndEvent(Event):
    pass


# Implementations.


class StreamStartEvent(Event):
    def __init__(self, start_mark=None, end_mark=None, encoding=None):
        self.start_mark = start_mark
        self.end_mark = end_mark
        self.encoding = encoding


class StreamEndEvent(Event):
    pass


class DocumentStartEvent(Event):
    def __init__(self, start_mark=None, end_mark=None, explicit=None, version=None, tags=None):
        self.start_mark = start_mark
        self.end_mark = end_mark
        self.explicit = explicit
        self.version = version
        self.tags = tags


class DocumentEndEvent(Event):
    def __init__(self, start_mark=None, end_mark=None, explicit=None):
        self.start_mark = start_mark
        self.end_mark = end_mark
        self.explicit = explicit


class AliasEvent(NodeEvent):
    pass


class ScalarEvent(NodeEvent):
    def __init__(self, anchor, tag, implicit, value, start_mark=None, end_mark=None, style=None):
        self.anchor = anchor
        self.tag = tag
        self.implicit = implicit
        self.value = value
        self.start_mark = start_mark
        self.end_mark = end_mark
        self.style = style


class SequenceStartEvent(CollectionStartEvent):
    pass


class SequenceEndEvent(CollectionEndEvent):
    pass


class MappingStartEvent(CollectionStartEvent):
    pass


class MappingEndEvent(CollectionEndEvent):
    pass
