include/tenzr/modules/nn/embedding.h¶

// Copyright 2026 The Tenzr Project Authors
//
// SPDX-License-Identifier: Apache-2.0
//
// 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
//
//      https://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.

#ifndef TENZR_MODULES_NN_EMBEDDING_H_
#define TENZR_MODULES_NN_EMBEDDING_H_

#include <cstdint>
#include <optional>
#include <string>

#include "tenzr/frontend/dtype.h"
#include "tenzr/frontend/tensor.h"
#include "tenzr/modules/nn/module.h"

namespace tenzr::nn {

  class Embedding : public Module {
   public:
    // Dynamic DType constructor (explicit dtype, optional seed)
    Embedding(int64_t num_embeddings, int64_t embedding_dim, DType dtype, std::optional<uint64_t> seed = std::nullopt);

    // Compile-time templated constructor using C++20 concepts (defaults to float via concepts::FloatingPoint<T>)
    template <typename T = float>
      requires concepts::FloatingPoint<T>
    Embedding(int64_t num_embeddings, int64_t embedding_dim, std::optional<uint64_t> seed = std::nullopt)
        : Embedding(num_embeddings, embedding_dim, DtypeOf<T>(), seed) {}

    // Tag dispatch constructor with explicit type: Embedding(std::type_identity<double>{}, 10, 16)
    template <typename T>
      requires concepts::FloatingPoint<T>
    explicit Embedding(std::type_identity<T>, int64_t num_embeddings, int64_t embedding_dim, std::optional<uint64_t> seed = std::nullopt)
        : Embedding(num_embeddings, embedding_dim, DtypeOf<T>(), seed) {}

    // Compile-time factory method: Embedding::create<double>(10, 16)
    template <typename T = float>
      requires concepts::FloatingPoint<T>
    static Embedding Create(int64_t num_embeddings, int64_t embedding_dim, std::optional<uint64_t> seed = std::nullopt) {
      return Embedding(num_embeddings, embedding_dim, DtypeOf<T>(), seed);
    }

    Tensor Forward(const Tensor& indices) override;

    Tensor& Weight() { return weight_; }
    const Tensor& Weight() const { return weight_; }

    int64_t NumEmbeddings() const { return num_embeddings_; }
    int64_t EmbeddingDim() const { return embedding_dim_; }

    std::string Name() const override { return "Embedding"; }

   private:
    int64_t num_embeddings_;
    int64_t embedding_dim_;
    Tensor weight_;
  };

}  // namespace tenzr::nn

#endif  // TENZR_MODULES_NN_EMBEDDING_H_