# coding=utf-8
# Copyright 2023 Authors: Wenhai Wang, Enze Xie, Xiang Li, Deng-Ping Fan,
# Kaitao Song, Ding Liang, Tong Lu, Ping Luo, Ling Shao and The HuggingFace Inc. team.
# 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.
""" Pvt model configuration"""

from collections import OrderedDict
from typing import Callable, List, Mapping

from packaging import version

from ...configuration_utils import PretrainedConfig
from ...onnx import OnnxConfig
from ...utils import logging


logger = logging.get_logger(__name__)


class PvtConfig(PretrainedConfig):
    r"""
    This is the configuration class to store the configuration of a [`PvtModel`]. It is used to instantiate an Pvt
    model according to the specified arguments, defining the model architecture. Instantiating a configuration with the
    defaults will yield a similar configuration to that of the Pvt
    [Xrenya/pvt-tiny-224](https://huggingface.co/Xrenya/pvt-tiny-224) architecture.

    Configuration objects inherit from [`PretrainedConfig`] and can be used to control the model outputs. Read the
    documentation from [`PretrainedConfig`] for more information.

    Args:
        image_size (`int`, *optional*, defaults to 224):
            The input image size
        num_channels (`int`, *optional*, defaults to 3):
            The number of input channels.
        num_encoder_blocks (`int`, *optional*, defaults to 4):
            The number of encoder blocks (i.e. stages in the Mix Transformer encoder).
        depths (`List[int]`, *optional*, defaults to `[2, 2, 2, 2]`):
            The number of layers in each encoder block.
        sequence_reduction_ratios (`List[int]`, *optional*, defaults to `[8, 4, 2, 1]`):
            Sequence reduction ratios in each encoder block.
        hidden_sizes (`List[int]`, *optional*, defaults to `[64, 128, 320, 512]`):
            Dimension of each of the encoder blocks.
        patch_sizes (`List[int]`, *optional*, defaults to `[4, 2, 2, 2]`):
            Patch size before each encoder block.
        strides (`List[int]`, *optional*, defaults to `[4, 2, 2, 2]`):
            Stride before each encoder block.
        num_attention_heads (`List[int]`, *optional*, defaults to `[1, 2, 5, 8]`):
            Number of attention heads for each attention layer in each block of the Transformer encoder.
        mlp_ratios (`List[int]`, *optional*, defaults to `[8, 8, 4, 4]`):
            Ratio of the size of the hidden layer compared to the size of the input layer of the Mix FFNs in the
            encoder blocks.
        hidden_act (`str` or `function`, *optional*, defaults to `"gelu"`):
            The non-linear activation function (function or string) in the encoder and pooler. If string, `"gelu"`,
            `"relu"`, `"selu"` and `"gelu_new"` are supported.
        hidden_dropout_prob (`float`, *optional*, defaults to 0.0):
            The dropout probability for all fully connected layers in the embeddings, encoder, and pooler.
        attention_probs_dropout_prob (`float`, *optional*, defaults to 0.0):
            The dropout ratio for the attention probabilities.
        initializer_range (`float`, *optional*, defaults to 0.02):
            The standard deviation of the truncated_normal_initializer for initializing all weight matrices.
        drop_path_rate (`float`, *optional*, defaults to 0.0):
            The dropout probability for stochastic depth, used in the blocks of the Transformer encoder.
        layer_norm_eps (`float`, *optional*, defaults to 1e-06):
            The epsilon used by the layer normalization layers.
        qkv_bias (`bool`, *optional*, defaults to `True`):
            Whether or not a learnable bias should be added to the queries, keys and values.
        num_labels ('int', *optional*, defaults to 1000):
            The number of classes.
    Example:

    ```python
    >>> from transformers import PvtModel, PvtConfig

    >>> # Initializing a PVT Xrenya/pvt-tiny-224 style configuration
    >>> configuration = PvtConfig()

    >>> # Initializing a model from the Xrenya/pvt-tiny-224 style configuration
    >>> model = PvtModel(configuration)

    >>> # Accessing the model configuration
    >>> configuration = model.config
    ```"""

    model_type = "pvt"

    def __init__(
        self,
        image_size: int = 224,
        num_channels: int = 3,
        num_encoder_blocks: int = 4,
        depths: List[int] = [2, 2, 2, 2],
        sequence_reduction_ratios: List[int] = [8, 4, 2, 1],
        hidden_sizes: List[int] = [64, 128, 320, 512],
        patch_sizes: List[int] = [4, 2, 2, 2],
        strides: List[int] = [4, 2, 2, 2],
        num_attention_heads: List[int] = [1, 2, 5, 8],
        mlp_ratios: List[int] = [8, 8, 4, 4],
        hidden_act: Mapping[str, Callable] = "gelu",
        hidden_dropout_prob: float = 0.0,
        attention_probs_dropout_prob: float = 0.0,
        initializer_range: float = 0.02,
        drop_path_rate: float = 0.0,
        layer_norm_eps: float = 1e-6,
        qkv_bias: bool = True,
        num_labels: int = 1000,
        **kwargs,
    ):
        super().__init__(**kwargs)

        self.image_size = image_size
        self.num_channels = num_channels
        self.num_encoder_blocks = num_encoder_blocks
        self.depths = depths
        self.sequence_reduction_ratios = sequence_reduction_ratios
        self.hidden_sizes = hidden_sizes
        self.patch_sizes = patch_sizes
        self.strides = strides
        self.mlp_ratios = mlp_ratios
        self.num_attention_heads = num_attention_heads
        self.hidden_act = hidden_act
        self.hidden_dropout_prob = hidden_dropout_prob
        self.attention_probs_dropout_prob = attention_probs_dropout_prob
        self.initializer_range = initializer_range
        self.drop_path_rate = drop_path_rate
        self.layer_norm_eps = layer_norm_eps
        self.num_labels = num_labels
        self.qkv_bias = qkv_bias


class PvtOnnxConfig(OnnxConfig):
    torch_onnx_minimum_version = version.parse("1.11")

    @property
    def inputs(self) -> Mapping[str, Mapping[int, str]]:
        return OrderedDict(
            [
                ("pixel_values", {0: "batch", 1: "num_channels", 2: "height", 3: "width"}),
            ]
        )

    @property
    def atol_for_validation(self) -> float:
        return 1e-4

    @property
    def default_onnx_opset(self) -> int:
        return 12
