"""
 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 numpy as np

from extensions.back.ForceStrictPrecision import ForceStrictPrecision
from mo.back.replacement import BackReplacementPattern
from mo.front.common.partial_infer.utils import int64_array
from mo.front.tf.graph_utils import create_op_node_with_second_input
from mo.graph.graph import Graph, rename_nodes
from mo.ops.const import Const
from mo.ops.shape import Shape
from mo.ops.strided_slice import StridedSlice
from mo.ops.unsqueeze import Unsqueeze


class PriorboxMutation(BackReplacementPattern):
    enabled = True
    force_shape_inference = True

    def run_before(self):
        return [ForceStrictPrecision]

    def pattern(self):
        return dict(
            nodes=[
                ('pb', {'type': lambda node_type: node_type in ['PriorBox', 'PriorBoxClustered']})
            ],
            edges=[]
        )

    def replace_pattern(self, graph: Graph, match: dict):
        node = match['pb']
        name = node.soft_get('name', node.id)

        graph.graph['cmd_params'].keep_shape_ops = True

        assert len(node.in_ports()) == 2

        begin = Const(graph, {'value': np.array([2], dtype=np.int32), 'name': name + '/ss_begin'}).create_node()
        end = Const(graph, {'value': np.array([4], dtype=np.int32), 'name': name + '/ss_end'}).create_node()
        stride = Const(graph, {'value': np.array([1], dtype=np.int32), 'name': name + '/ss_stride'}).create_node()

        shape_0 = Shape(graph, {'name': name + '/0_port'}).create_node()
        ss_0 = StridedSlice(graph, {'name': name + '/ss_0_port',
                                    'begin_mask': np.array([1], dtype=np.int32),
                                    'end_mask': np.array([0], dtype=np.int32),
                                    'new_axis_mask': np.array([0], dtype=np.int32),
                                    'shrink_axis_mask': np.array([0], dtype=np.int32),
                                    'ellipsis_mask': np.array([0], dtype=np.int32)}).create_node()

        shape_0.out_port(0).connect(ss_0.in_port(0))
        begin.out_port(0).connect(ss_0.in_port(1))
        end.out_port(0).connect(ss_0.in_port(2))
        stride.out_port(0).connect(ss_0.in_port(3))

        source = node.in_port(0).get_connection().get_source()
        node.in_port(0).disconnect()
        source.connect(shape_0.in_port(0))
        ss_0.out_port(0).connect(node.in_port(0))

        shape_1 = Shape(graph, {'name': name + '/1_port'}).create_node()
        ss_1 = StridedSlice(graph, {'name': name + '/ss_1_port',
                                    'begin_mask': np.array([1], dtype=np.int32),
                                    'end_mask': np.array([0], dtype=np.int32),
                                    'new_axis_mask': np.array([0], dtype=np.int32),
                                    'shrink_axis_mask': np.array([0], dtype=np.int32),
                                    'ellipsis_mask': np.array([0], dtype=np.int32)}).create_node()

        shape_1.out_port(0).connect(ss_1.in_port(0))
        begin.out_port(0).connect(ss_1.in_port(1))
        end.out_port(0).connect(ss_1.in_port(2))
        stride.out_port(0).connect(ss_1.in_port(3))

        source = node.in_port(1).get_connection().get_source()
        node.in_port(1).disconnect()
        source.connect(shape_1.in_port(0))
        ss_1.out_port(0).connect(node.in_port(1))

        ss_0['force_precision_in_ports'] = {1: 'int64', 2: 'int64', 3: 'int64'}
        ss_1['force_precision_in_ports'] = {1: 'int64', 2: 'int64', 3: 'int64'}

        node['need_shape_inference'] = True
        node['override_output_shape'] = True
        node['V10_infer'] = True
        unsqueeze = create_op_node_with_second_input(graph, Unsqueeze, int64_array([0]), {'name': name + '/unsqueeze'})
        naked_priorbox_name = name + '/naked_not_unsqueezed'
        rename_nodes([(node, naked_priorbox_name), (unsqueeze, name)])

        node.out_port(0).get_connection().set_source(unsqueeze.out_port(0))
        node.out_port(0).connect(unsqueeze.in_port(0))
