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#     http://www.apache.org/licenses/LICENSE-2.0
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""" MobileBERT model configuration """

import logging

from .configuration_utils import PretrainedConfig


logger = logging.getLogger(__name__)

MOBILEBERT_PRETRAINED_CONFIG_ARCHIVE_MAP = {
    "mobilebert-uncased": "https://s3.amazonaws.com/models.huggingface.co/bert/google/mobilebert-uncased/config.json"
}


class MobileBertConfig(PretrainedConfig):
    r"""
        This is the configuration class to store the configuration of a :class:`~transformers.MobileBertModel`.
        It is used to instantiate a MobileBERT model according to the specified arguments, defining the model
        architecture.

        Configuration objects inherit from  :class:`~transformers.PretrainedConfig` and can be used
        to control the model outputs. Read the documentation from  :class:`~transformers.PretrainedConfig`
        for more information.


        Args:
            vocab_size (:obj:`int`, optional, defaults to 30522):
                Vocabulary size of the MobileBERT model. Defines the different tokens that
                can be represented by the `inputs_ids` passed to the forward method of :class:`~transformers.MobileBertModel`.
            hidden_size (:obj:`int`, optional, defaults to 512):
                Dimensionality of the encoder layers and the pooler layer.
            num_hidden_layers (:obj:`int`, optional, defaults to 24):
                Number of hidden layers in the Transformer encoder.
            num_attention_heads (:obj:`int`, optional, defaults to 4):
                Number of attention heads for each attention layer in the Transformer encoder.
            intermediate_size (:obj:`int`, optional, defaults to 512):
                Dimensionality of the "intermediate" (i.e., feed-forward) layer in the Transformer encoder.
            hidden_act (:obj:`str` or :obj:`function`, optional, defaults to "relu"):
                The non-linear activation function (function or string) in the encoder and pooler.
                If string, "gelu", "relu", "swish" and "gelu_new" are supported.
            hidden_dropout_prob (:obj:`float`, optional, defaults to 0.0):
                The dropout probability for all fully connected layers in the embeddings, encoder, and pooler.
            attention_probs_dropout_prob (:obj:`float`, optional, defaults to 0.1):
                The dropout ratio for the attention probabilities.
            max_position_embeddings (:obj:`int`, optional, defaults to 512):
                The maximum sequence length that this model might ever be used with.
                Typically set this to something large just in case (e.g., 512 or 1024 or 2048).
            type_vocab_size (:obj:`int`, optional, defaults to 2):
                The vocabulary size of the `token_type_ids` passed into :class:`~transformers.MobileBertModel`.
            initializer_range (:obj:`float`, optional, defaults to 0.02):
                The standard deviation of the truncated_normal_initializer for initializing all weight matrices.
            layer_norm_eps (:obj:`float`, optional, defaults to 1e-12):
                The epsilon used by the layer normalization layers.

            pad_token_id (:obj:`int`, optional, defaults to 0):
                The ID of the token in the word embedding to use as padding.
            embedding_size (:obj:`int`, optional, defaults to 128):
                The dimension of the word embedding vectors.
            trigram_input (:obj:`bool`, optional, defaults to True):
                Use a convolution of trigram as input.
            use_bottleneck (:obj:`bool`, optional, defaults to True):
                Whether to use bottleneck in BERT.
            intra_bottleneck_size (:obj:`int`, optional, defaults to 128):
                Size of bottleneck layer output.
            use_bottleneck_attention (:obj:`bool`, optional, defaults to False):
                Whether to use attention inputs from the bottleneck transformation.
            key_query_shared_bottleneck (:obj:`bool`, optional, defaults to True):
                Whether to use the same linear transformation for query&key in the bottleneck.
            num_feedforward_networks (:obj:`int`, optional, defaults to 4):
                Number of FFNs in a block.
            normalization_type (:obj:`str`, optional, defaults to "no_norm"):
                The normalization type in BERT.

        Example:

            >>> from transformers import MobileBertModel, MobileBertConfig

            >>> # Initializing a MobileBERT configuration
            >>> configuration = MobileBertConfig()

            >>> # Initializing a model from the configuration above
            >>> model = MobileBertModel(configuration)

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

        Attributes:
            pretrained_config_archive_map (Dict[str, str]):
                A dictionary containing all the available pre-trained checkpoints.
    """
    pretrained_config_archive_map = MOBILEBERT_PRETRAINED_CONFIG_ARCHIVE_MAP
    model_type = "mobilebert"

    def __init__(
        self,
        vocab_size=30522,
        hidden_size=512,
        num_hidden_layers=24,
        num_attention_heads=4,
        intermediate_size=512,
        hidden_act="relu",
        hidden_dropout_prob=0.0,
        attention_probs_dropout_prob=0.1,
        max_position_embeddings=512,
        type_vocab_size=2,
        initializer_range=0.02,
        layer_norm_eps=1e-12,
        pad_token_id=0,
        embedding_size=128,
        trigram_input=True,
        use_bottleneck=True,
        intra_bottleneck_size=128,
        use_bottleneck_attention=False,
        key_query_shared_bottleneck=True,
        num_feedforward_networks=4,
        normalization_type="no_norm",
        classifier_activation=True,
        **kwargs
    ):
        super().__init__(pad_token_id=pad_token_id, **kwargs)

        self.vocab_size = vocab_size
        self.hidden_size = hidden_size
        self.num_hidden_layers = num_hidden_layers
        self.num_attention_heads = num_attention_heads
        self.hidden_act = hidden_act
        self.intermediate_size = intermediate_size
        self.hidden_dropout_prob = hidden_dropout_prob
        self.attention_probs_dropout_prob = attention_probs_dropout_prob
        self.max_position_embeddings = max_position_embeddings
        self.type_vocab_size = type_vocab_size
        self.initializer_range = initializer_range
        self.layer_norm_eps = layer_norm_eps
        self.embedding_size = embedding_size
        self.trigram_input = trigram_input
        self.use_bottleneck = use_bottleneck
        self.intra_bottleneck_size = intra_bottleneck_size
        self.use_bottleneck_attention = use_bottleneck_attention
        self.key_query_shared_bottleneck = key_query_shared_bottleneck
        self.num_feedforward_networks = num_feedforward_networks
        self.normalization_type = normalization_type
        self.classifier_activation = classifier_activation

        if self.use_bottleneck:
            self.true_hidden_size = intra_bottleneck_size
        else:
            self.true_hidden_size = hidden_size
