"""
 Copyright (C) 2018-2020 Intel Corporation

 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.
"""

import networkx as nx
import numpy as np

from mo.graph.graph import Node, Graph
from mo.ops.op import Op
from mo.utils.utils import symm_match_shapes


class TensorArrayGather(Op):
    op = "TensorArrayGatherV3"

    def __init__(self, graph: Graph, attrs: dict):
        mandatory_props = {
            'type': __class__.op,
            'op': __class__.op,
            'infer': TensorArrayGather.array_infer,
        }
        super().__init__(graph, mandatory_props, attrs)

    @staticmethod
    def array_infer(node: Node):
        assert len(node.in_nodes()) == 3

        handle = node.in_node(0)
        indices = node.in_node(1)
        flow_in = node.in_node(2)

        ta_node = Node(node.graph, str(handle.value))

        if ta_node.has_valid('element_shape') and ta_node.element_shape is not None and len(ta_node.element_shape) > 0:
            assert symm_match_shapes(ta_node['element_shape'], node.element_shape)
        else:
            ta_node['element_shape'] = node.element_shape
        data_shape = ta_node['element_shape']
        assert -1 not in data_shape or data_shape.size == 2 and data_shape[0] == -1 and data_shape[1] != -1

        assert ta_node.has_valid('size')
        size = ta_node['size']

        assert size > 0

        output_shape = [size] + [data_shape[i] for i in range(len(data_shape))]
        output_value = None

        for _, out_node in node.graph.out_edges(node.id):
            node.graph.node[out_node]['shape'] = np.array(output_shape)
            node.graph.node[out_node]['value'] = None if output_value is None else np.array(output_value)
