// Copyright (c) 2020 PaddlePaddle Authors. 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.

#pragma once

#include <opencv2/imgproc.hpp>

namespace PaddleOCR {

struct OCRPredictResult {
  std::vector<std::vector<int>> box;
  std::string text;
  float score = -1.0;
  float cls_score;
  int cls_label = -1;
};

struct StructurePredictResult {
  std::vector<float> box;
  std::vector<std::vector<int>> cell_box;
  std::string type;
  std::vector<OCRPredictResult> text_res;
  std::string html;
  float html_score = -1;
  float confidence;
};

class Utility {
public:
  static std::vector<std::string> ReadDict(const std::string &path) noexcept;

  static void VisualizeBboxes(const cv::Mat &srcimg,
                              const std::vector<OCRPredictResult> &ocr_result,
                              const std::string &save_path) noexcept;

  static void VisualizeBboxes(const cv::Mat &srcimg,
                              const StructurePredictResult &structure_result,
                              const std::string &save_path) noexcept;

  template <class ForwardIterator>
  inline static size_t argmax(ForwardIterator first,
                              ForwardIterator last) noexcept {
    return std::distance(first, std::max_element(first, last));
  }

  static void GetAllFiles(const char *dir_name,
                          std::vector<std::string> &all_inputs) noexcept;

  static cv::Mat
  GetRotateCropImage(const cv::Mat &srcimage,
                     const std::vector<std::vector<int>> &box) noexcept;

  static std::vector<size_t> argsort(const std::vector<float> &array) noexcept;

  static std::string basename(const std::string &filename) noexcept;

  static bool PathExists(const char *path) noexcept;
  static inline bool PathExists(const std::string &path) noexcept {
    return PathExists(path.c_str());
  }

  static void CreateDir(const char *path) noexcept;
  static inline void CreateDir(const std::string &path) noexcept {
    CreateDir(path.c_str());
  }

  static void
  print_result(const std::vector<OCRPredictResult> &ocr_result) noexcept;

  static cv::Mat crop_image(const cv::Mat &img,
                            const std::vector<int> &area) noexcept;
  static cv::Mat crop_image(const cv::Mat &img,
                            const std::vector<float> &area) noexcept;

  static void sort_boxes(std::vector<OCRPredictResult> &ocr_result) noexcept;

  static std::vector<int>
  xyxyxyxy2xyxy(const std::vector<std::vector<int>> &box) noexcept;
  static std::vector<int> xyxyxyxy2xyxy(const std::vector<int> &box) noexcept;

  static float fast_exp(float x) noexcept;
  static std::vector<float>
  activation_function_softmax(const std::vector<float> &src) noexcept;
  static float iou(const std::vector<int> &box1,
                   const std::vector<int> &box2) noexcept;
  static float iou(const std::vector<float> &box1,
                   const std::vector<float> &box2) noexcept;

private:
  static bool comparison_box(const OCRPredictResult &result1,
                             const OCRPredictResult &result2) noexcept {
    if (result1.box[0][1] < result2.box[0][1]) {
      return true;
    } else if (result1.box[0][1] == result2.box[0][1]) {
      return result1.box[0][0] < result2.box[0][0];
    } else {
      return false;
    }
  }
};

} // namespace PaddleOCR