/*
 * COPYRIGHT AND PERMISSION NOTICE
 * Penn Software MSCKF_VIO
 * Copyright (C) 2017 The Trustees of the University of Pennsylvania
 * All rights reserved.
 */

#include <msckf_vio/utils.h>
#include <vector>

namespace msckf_vio {
namespace utils {

Eigen::Isometry3d getTransformEigen(const ros::NodeHandle &nh,
                                    const std::string &field) {
  Eigen::Isometry3d T;
  cv::Mat c = getTransformCV(nh, field);

  T.linear()(0, 0)   = c.at<double>(0, 0);
  T.linear()(0, 1)   = c.at<double>(0, 1);
  T.linear()(0, 2)   = c.at<double>(0, 2);
  T.linear()(1, 0)   = c.at<double>(1, 0);
  T.linear()(1, 1)   = c.at<double>(1, 1);
  T.linear()(1, 2)   = c.at<double>(1, 2);
  T.linear()(2, 0)   = c.at<double>(2, 0);
  T.linear()(2, 1)   = c.at<double>(2, 1);
  T.linear()(2, 2)   = c.at<double>(2, 2);
  T.translation()(0) = c.at<double>(0, 3);
  T.translation()(1) = c.at<double>(1, 3);
  T.translation()(2) = c.at<double>(2, 3);
  return T;
}

cv::Mat getTransformCV(const ros::NodeHandle &nh,
                       const std::string &field) {
  cv::Mat T;
  try {
    // first try reading kalibr format
    T = getKalibrStyleTransform(nh, field);
  } catch (std::runtime_error &e) {
    // maybe it's the old style format?
    ROS_DEBUG_STREAM("cannot read transform " << field
                     << " in kalibr format, trying old one!");
    try {
      T = getVec16Transform(nh, field);
    } catch (std::runtime_error &e) {
      std::string msg = "cannot read transform " + field + " error: " + e.what();
      ROS_ERROR_STREAM(msg);
      throw std::runtime_error(msg);
    }
  }
  return T;
}

cv::Mat getVec16Transform(const ros::NodeHandle &nh,
                          const std::string &field) {
  std::vector<double> v;
  nh.getParam(field, v);
  if (v.size() != 16) {
    throw std::runtime_error("invalid vec16!");
  }
  cv::Mat T = cv::Mat(v).clone().reshape(1, 4); // one channel 4 rows
  return T;
}

cv::Mat getKalibrStyleTransform(const ros::NodeHandle &nh,
                                const std::string &field) {
  cv::Mat T = cv::Mat::eye(4, 4, CV_64FC1);
  XmlRpc::XmlRpcValue lines;
  if (!nh.getParam(field, lines)) {
    throw (std::runtime_error("cannot find transform " + field));
  }
  if (lines.size() != 4 || lines.getType() != XmlRpc::XmlRpcValue::TypeArray) {
    throw (std::runtime_error("invalid transform " + field));
  }
  for (int i = 0; i < lines.size(); i++) {
    if (lines.size() != 4 || lines.getType() != XmlRpc::XmlRpcValue::TypeArray) {
      throw (std::runtime_error("bad line for transform " + field));
    }
    for (int j = 0; j < lines[i].size(); j++) {
      if (lines[i][j].getType() != XmlRpc::XmlRpcValue::TypeDouble) {
        throw (std::runtime_error("bad value for transform " + field));
      } else {
        T.at<double>(i,j) = static_cast<double>(lines[i][j]);
      }
    }
  }
  return T;
}

} // namespace utils
} // namespace msckf_vio