// Copyright (c) Meta Platforms, Inc. and affiliates.
// All rights reserved.
//
// This source code is licensed under the license found in the
// LICENSE file in the root directory of this source tree.

#include "ggml/ggml.h"
#include "ggml/ggml-alloc.h"

#include "common.h"
#include "common-ggml.h"

#include "unity_model_loader.h"

void unity_model_loader::load_hparams(fairseq2_model& model, std::ifstream &fin)
{
    auto& hparams = (unity_hparams&)model.hparams;

    fin.read((char*) &hparams.model_dim, sizeof(hparams.model_dim));
    fin.read((char*) &hparams.w2v2_encoder_config__model_dim, sizeof(hparams.w2v2_encoder_config__model_dim));
    fin.read((char*) &hparams.w2v2_encoder_config__max_seq_len, sizeof(hparams.w2v2_encoder_config__max_seq_len));
    fin.read((char*) &hparams.w2v2_encoder_config__feature_dim, sizeof(hparams.w2v2_encoder_config__feature_dim));
    fin.read((char*) &hparams.w2v2_encoder_config__use_fbank, sizeof(hparams.w2v2_encoder_config__use_fbank));
    fin.read((char*) &hparams.w2v2_encoder_config__first_pass_dropout_p, sizeof(hparams.w2v2_encoder_config__first_pass_dropout_p));
    fin.read((char*) &hparams.w2v2_encoder_config__layer_norm_features, sizeof(hparams.w2v2_encoder_config__layer_norm_features));
    fin.read((char*) &hparams.w2v2_encoder_config__feature_extractor_bias, sizeof(hparams.w2v2_encoder_config__feature_extractor_bias));
    fin.read((char*) &hparams.w2v2_encoder_config__feature_extractor_layer_norm_convs, sizeof(hparams.w2v2_encoder_config__feature_extractor_layer_norm_convs));
    fin.read((char*) &hparams.w2v2_encoder_config__feature_grad_scale, sizeof(hparams.w2v2_encoder_config__feature_grad_scale));
    fin.read((char*) &hparams.w2v2_encoder_config__num_fbank_channels, sizeof(hparams.w2v2_encoder_config__num_fbank_channels));
    fin.read((char*) &hparams.w2v2_encoder_config__fbank_stride, sizeof(hparams.w2v2_encoder_config__fbank_stride));
    fin.read((char*) &hparams.w2v2_encoder_config__sample_fbank_every_k, sizeof(hparams.w2v2_encoder_config__sample_fbank_every_k));
    fin.read((char*) &hparams.w2v2_encoder_config__pos_encoder_depth, sizeof(hparams.w2v2_encoder_config__pos_encoder_depth));
    fin.read((char*) &hparams.w2v2_encoder_config__pos_conv_kernel_size, sizeof(hparams.w2v2_encoder_config__pos_conv_kernel_size));
    fin.read((char*) &hparams.w2v2_encoder_config__num_pos_conv_groups, sizeof(hparams.w2v2_encoder_config__num_pos_conv_groups));
    fin.read((char*) &hparams.w2v2_encoder_config__use_conformer, sizeof(hparams.w2v2_encoder_config__use_conformer));
    fin.read((char*) &hparams.w2v2_encoder_config__num_encoder_layers, sizeof(hparams.w2v2_encoder_config__num_encoder_layers));
    fin.read((char*) &hparams.w2v2_encoder_config__num_encoder_attn_heads, sizeof(hparams.w2v2_encoder_config__num_encoder_attn_heads));
    fin.read((char*) &hparams.w2v2_encoder_config__ffn_inner_dim, sizeof(hparams.w2v2_encoder_config__ffn_inner_dim));
    fin.read((char*) &hparams.w2v2_encoder_config__dropout_p, sizeof(hparams.w2v2_encoder_config__dropout_p));
    fin.read((char*) &hparams.w2v2_encoder_config__attn_dropout_p, sizeof(hparams.w2v2_encoder_config__attn_dropout_p));
    fin.read((char*) &hparams.w2v2_encoder_config__layer_drop_p, sizeof(hparams.w2v2_encoder_config__layer_drop_p));
    fin.read((char*) &hparams.w2v2_encoder_config__norm_order, sizeof(hparams.w2v2_encoder_config__norm_order));
    fin.read((char*) &hparams.w2v2_encoder_config__depthwise_conv_kernel_size, sizeof(hparams.w2v2_encoder_config__depthwise_conv_kernel_size));
    fin.read((char*) &hparams.nllb_config__model_dim, sizeof(hparams.nllb_config__model_dim));
    fin.read((char*) &hparams.nllb_config__max_seq_len, sizeof(hparams.nllb_config__max_seq_len));
    fin.read((char*) &hparams.nllb_config__vocabulary_size, sizeof(hparams.nllb_config__vocabulary_size));
    fin.read((char*) &hparams.nllb_config__pad_idx, sizeof(hparams.nllb_config__pad_idx));
    fin.read((char*) &hparams.nllb_config__num_encoder_layers, sizeof(hparams.nllb_config__num_encoder_layers));
    fin.read((char*) &hparams.nllb_config__num_decoder_layers, sizeof(hparams.nllb_config__num_decoder_layers));
    fin.read((char*) &hparams.nllb_config__num_encoder_attn_heads, sizeof(hparams.nllb_config__num_encoder_attn_heads));
    fin.read((char*) &hparams.nllb_config__num_decoder_attn_heads, sizeof(hparams.nllb_config__num_decoder_attn_heads));
    fin.read((char*) &hparams.nllb_config__ffn_inner_dim, sizeof(hparams.nllb_config__ffn_inner_dim));
    fin.read((char*) &hparams.nllb_config__dropout_p, sizeof(hparams.nllb_config__dropout_p));
    fin.read((char*) &hparams.t2u_config__model_dim, sizeof(hparams.t2u_config__model_dim));
    fin.read((char*) &hparams.t2u_config__unit_max_seq_len, sizeof(hparams.t2u_config__unit_max_seq_len));
    fin.read((char*) &hparams.t2u_config__unit_vocabulary_size, sizeof(hparams.t2u_config__unit_vocabulary_size));
    fin.read((char*) &hparams.t2u_config__unit_pad_idx, sizeof(hparams.t2u_config__unit_pad_idx));
    fin.read((char*) &hparams.t2u_config__num_encoder_layers, sizeof(hparams.t2u_config__num_encoder_layers));
    fin.read((char*) &hparams.t2u_config__num_decoder_layers, sizeof(hparams.t2u_config__num_decoder_layers));
    fin.read((char*) &hparams.t2u_config__num_encoder_attn_heads, sizeof(hparams.t2u_config__num_encoder_attn_heads));
    fin.read((char*) &hparams.t2u_config__num_decoder_attn_heads, sizeof(hparams.t2u_config__num_decoder_attn_heads));
    fin.read((char*) &hparams.t2u_config__ffn_inner_dim, sizeof(hparams.t2u_config__ffn_inner_dim));
    fin.read((char*) &hparams.t2u_config__dropout_p, sizeof(hparams.t2u_config__dropout_p));
    fin.read((char*) &hparams.use_text_encoder, sizeof(hparams.use_text_encoder));
    fin.read((char*) &hparams.use_conformer_adaptor, sizeof(hparams.use_conformer_adaptor));
    fin.read((char*) &hparams.num_adaptor_layers, sizeof(hparams.num_adaptor_layers));
    fin.read((char*) &hparams.adaptor_kernel_size, sizeof(hparams.adaptor_kernel_size));
    fin.read((char*) &hparams.adaptor_stride, sizeof(hparams.adaptor_stride));
    fin.read((char*) &hparams.adaptor_layer_norm, sizeof(hparams.adaptor_layer_norm));
    fin.read((char*) &hparams.adaptor_dropout_p, sizeof(hparams.adaptor_dropout_p));
};

std::size_t
unity_model_loader::compute_context_size(void* raw_hparams)
{
    // TODO
    auto hparams = (unity_hparams&)raw_hparams;
    return hparams.model_dim * 1024 * 100;
};

struct UnityArch {
    struct TransformerDecoder text_decoder;
};

void unity_model_loader::tensors_alloc(fairseq2_model &model)
{
    auto hparams = (unity_hparams&)model.hparams;
    auto& arch = (UnityArch&)model.arch;
    const auto ctx = model.ctx;
    auto tensors = model.tensors;

    const auto vocab_size = hparams.nllb_config__vocabulary_size;
    const auto model_dim = hparams.nllb_config__model_dim;

    // This can be simplified by adding syntax sugar

    // frontend
    // arch.frontend_embed_w = ggml_new_tensor_2d(ctx, GGML_TYPE_F32, vocab_size, dim);
    // tensor_map["text_decoder_frontend.embed.weight"] = arch.frontend_embed_w;

    // layers
    {
        const auto n_layers = hparams.nllb_config__num_decoder_layers;
        arch.text_decoder.layers = std::vector<TransformerDecoderLayer>(n_layers);
        auto layers = arch.text_decoder.layers;
        auto num_heads = hparams.nllb_config__num_decoder_attn_heads;
        for (int i = 0; i < n_layers; ++i) {
            auto prefix = "text_decoder.layers." + std::to_string(i);
            MultiheadAttention_init(layers[i].self_attn, model, prefix + "self_attn", model_dim, num_heads);
            LayerNorm_init(layers[i].self_attn_norm, model, prefix + "self_attn_norm", model_dim);
        }
    }

    // // layer_norm
    // arch.layer_norm_w = ggml_new_tensor_1d(ctx, GGML_TYPE_F32, dim);
    // tensor_map["text_decoder.layer_norm.weight"] = arch.layer_norm_w;
    // arch.layer_norm_b = ggml_new_tensor_1d(ctx, GGML_TYPE_F32, dim);
    // tensor_map["text_decoder.layer_norm.bias"] = arch.layer_norm_b;
};

extern "C" void load_unity_ggml_file(fairseq2_model& model, const char* fname) {
    return load_fairseq2_ggml_file<unity_model_loader>(model, fname);
}