#
# Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

from onnx_graphsurgeon.logger.logger import G_LOGGER
from onnx_graphsurgeon.ir.tensor import Tensor
from onnx_graphsurgeon.util import misc

from collections import OrderedDict
from typing import List, Dict


class Node(object):
    def __init__(
        self,
        op: str,
        name: str = None,
        attrs: Dict[str, object] = None,
        inputs: List["Tensor"] = None,
        outputs: List["Tensor"] = None,
    ):
        """
        A node represents an operation in a graph, and consumes zero or more Tensors, and produces zero or more Tensors.

        Args:
            op (str): The operation this node performs.

            name (str): The name of this node.
            attrs (Dict[str, object]): A dictionary that maps attribute names to their values.
            inputs (List[Tensor]): A list of zero or more input Tensors.
            outputs (List[Tensor]): A list of zero or more output Tensors.
        """
        self.op = op
        self.name = misc.default_value(name, "")
        self.attrs = misc.default_value(attrs, OrderedDict())
        self.inputs = misc.SynchronizedList(self, field_name="outputs", initial=misc.default_value(inputs, []))
        self.outputs = misc.SynchronizedList(self, field_name="inputs", initial=misc.default_value(outputs, []))

    def i(self, tensor_idx=0, producer_idx=0):
        """
        Convenience function to get a producer node of one of this node's input tensors.
        Note that the parameters are swapped compared to the o() function; this is because tensors are likely to have only a single producer

        For example:
        ::

            assert node.i() == node.inputs[0].inputs[0]
            assert node.i(1, 2) == node.inputs[1].inputs[2]

        Args:
            tensor_idx (int): The index of the input tensor of this node. Defaults to 0.
            producer_idx (int): The index of the producer of the input tensor, if the tensor has multiple producers. Defaults to 0

        Returns:
            Node: The specified producer (input) node.
        """
        return self.inputs[tensor_idx].inputs[producer_idx]

    def o(self, consumer_idx=0, tensor_idx=0):
        """
        Convenience function to get a consumer node of one of this node's output tensors.

        For example:
        ::

            assert node.o() == node.outputs[0].outputs[0]
            assert node.o(2, 1) == node.outputs[1].outputs[2]

        Args:
            consumer_idx (int): The index of the consumer of the input tensor. Defaults to 0.
            tensor_idx (int): The index of the output tensor of this node, if the node has multiple outputs. Defaults to 0.

        Returns:
            Node: The specified consumer (output) node
        """
        return self.outputs[tensor_idx].outputs[consumer_idx]

    def __setattr__(self, name, value):
        if name in ["inputs", "outputs"]:
            try:
                getattr(self, name).clear()
                getattr(self, name).extend(value)
            except AttributeError:
                super().__setattr__(name, value)
        else:
            super().__setattr__(name, value)

    def copy(self, inputs: List["Tensor"] = None, outputs: List["Tensor"] = None, tensor_map=None):
        """
        Makes a shallow copy of this node, overriding input and output information.

        Note: Generally, you should only ever make a copy of a Graph.
        """
        from onnx_graphsurgeon.ir.graph import Graph

        new_attrs = OrderedDict()
        for name, attr in self.attrs.items():
            if isinstance(attr, Graph):
                new_attrs[name] = attr.copy(tensor_map)
            else:
                new_attrs[name] = attr

        return Node(self.op, self.name, new_attrs, inputs=inputs, outputs=outputs)

    def __str__(self):
        ret = "{:} ({:})".format(self.name, self.op)

        def add_io(name, io):
            nonlocal ret
            ret += "\n\t{:}: [".format(name)
            for elem in io:
                ret += "\n\t\t{:}".format(elem)
            ret += "\n\t]"

        add_io("Inputs", self.inputs)
        add_io("Outputs", self.outputs)

        if self.attrs:
            ret += "\nAttributes: {:}".format(self.attrs)
        return ret

    def __repr__(self):
        return self.__str__()

    def __eq__(self, other):
        """
        Check whether two nodes are equal by comparing name, attributes, op, inputs, and outputs.
        """
        G_LOGGER.verbose("Comparing node: {:} with {:}".format(self.name, other.name))
        attrs_match = self.name == other.name and self.op == other.op and self.attrs == other.attrs
        inputs_match = len(self.inputs) == len(other.inputs) and all(
            [inp == other_inp for inp, other_inp in zip(self.inputs, other.inputs)]
        )
        outputs_match = len(self.outputs) == len(other.outputs) and all(
            [out == other_out for out, other_out in zip(self.outputs, other.outputs)]
        )
        return attrs_match and inputs_match and outputs_match
