// sherpa-onnx/csrc/offline-moonshine-model.h
//
// Copyright (c)  2024  Xiaomi Corporation
#ifndef SHERPA_ONNX_CSRC_OFFLINE_MOONSHINE_MODEL_H_
#define SHERPA_ONNX_CSRC_OFFLINE_MOONSHINE_MODEL_H_

#include <memory>
#include <string>
#include <utility>
#include <vector>

#include "onnxruntime_cxx_api.h"  // NOLINT
#include "sherpa-onnx/csrc/offline-model-config.h"

namespace sherpa_onnx {

// please see
// https://github.com/k2-fsa/sherpa-onnx/blob/master/scripts/moonshine/test.py
class OfflineMoonshineModel {
 public:
  explicit OfflineMoonshineModel(const OfflineModelConfig &config);

  template <typename Manager>
  OfflineMoonshineModel(Manager *mgr, const OfflineModelConfig &config);

  ~OfflineMoonshineModel();

  /** Run the preprocessor model.
   *
   * @param audio A float32 tensor of shape (batch_size, num_samples)
   *
   * @return Return a float32 tensor of shape (batch_size, T, dim) that
   *         can be used as the input of ForwardEncoder()
   */
  Ort::Value ForwardPreprocessor(Ort::Value audio) const;

  /** Run the encoder model.
   *
   * @param features A float32 tensor of shape (batch_size, T, dim)
   * @param features_len A int32 tensor of shape (batch_size,)
   * @returns A float32 tensor of shape (batch_size, T, dim).
   */
  Ort::Value ForwardEncoder(Ort::Value features, Ort::Value features_len) const;

  /** Run the uncached decoder.
   *
   * @param token A int32 tensor of shape (batch_size, num_tokens)
   * @param seq_len A int32 tensor of shape (batch_size,) containing number
   *                of predicted tokens so far
   * @param encoder_out A float32 tensor of shape (batch_size, T, dim)
   *
   * @returns Return a pair:
   *
   *          - logits, a float32 tensor of shape (batch_size, 1, dim)
   *          - states, a list of states
   */
  std::pair<Ort::Value, std::vector<Ort::Value>> ForwardUnCachedDecoder(
      Ort::Value token, Ort::Value seq_len, Ort::Value encoder_out) const;

  /** Run the cached decoder.
   *
   * @param token A int32 tensor of shape (batch_size, num_tokens)
   * @param seq_len A int32 tensor of shape (batch_size,) containing number
   *                of predicted tokens so far
   * @param encoder_out A float32 tensor of shape (batch_size, T, dim)
   * @param states A list of previous states
   *
   * @returns Return a pair:
   *          - logits, a float32 tensor of shape (batch_size, 1, dim)
   *          - states, a list of new states
   */
  std::pair<Ort::Value, std::vector<Ort::Value>> ForwardCachedDecoder(
      Ort::Value token, Ort::Value seq_len, Ort::Value encoder_out,
      std::vector<Ort::Value> states) const;

  /** Return an allocator for allocating memory
   */
  OrtAllocator *Allocator() const;

 private:
  class Impl;
  std::unique_ptr<Impl> impl_;
};

}  // namespace sherpa_onnx

#endif  // SHERPA_ONNX_CSRC_OFFLINE_MOONSHINE_MODEL_H_