///////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2016, Carnegie Mellon University and University of Cambridge,
// all rights reserved.
//
// THIS SOFTWARE IS PROVIDED “AS IS” FOR ACADEMIC USE ONLY AND ANY EXPRESS
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// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Notwithstanding the license granted herein, Licensee acknowledges that certain components
// of the Software may be covered by so-called “open source” software licenses (“Open Source
// Components”), which means any software licenses approved as open source licenses by the
// Open Source Initiative or any substantially similar licenses, including without limitation any
// license that, as a condition of distribution of the software licensed under such license,
// requires that the distributor make the software available in source code format. Licensor shall
// provide a list of Open Source Components for a particular version of the Software upon
// Licensee’s request. Licensee will comply with the applicable terms of such licenses and to
// the extent required by the licenses covering Open Source Components, the terms of such
// licenses will apply in lieu of the terms of this Agreement. To the extent the terms of the
// licenses applicable to Open Source Components prohibit any of the restrictions in this
// License Agreement with respect to such Open Source Component, such restrictions will not
// apply to such Open Source Component. To the extent the terms of the licenses applicable to
// Open Source Components require Licensor to make an offer to provide source code or
// related information in connection with the Software, such offer is hereby made. Any request
// for source code or related information should be directed to cl-face-tracker-distribution@lists.cam.ac.uk
// Licensee acknowledges receipt of notices for the Open Source Components for the initial
// delivery of the Software.

//     * Any publications arising from the use of this software, including but
//       not limited to academic journal and conference publications, technical
//       reports and manuals, must cite at least one of the following works:
//
//       OpenFace: an open source facial behavior analysis toolkit
//       Tadas Baltrušaitis, Peter Robinson, and Louis-Philippe Morency
//       in IEEE Winter Conference on Applications of Computer Vision, 2016  
//
//       Rendering of Eyes for Eye-Shape Registration and Gaze Estimation
//       Erroll Wood, Tadas Baltrušaitis, Xucong Zhang, Yusuke Sugano, Peter Robinson, and Andreas Bulling 
//       in IEEE International. Conference on Computer Vision (ICCV),  2015 
//
//       Cross-dataset learning and person-speci?c normalisation for automatic Action Unit detection
//       Tadas Baltrušaitis, Marwa Mahmoud, and Peter Robinson 
//       in Facial Expression Recognition and Analysis Challenge, 
//       IEEE International Conference on Automatic Face and Gesture Recognition, 2015 
//
//       Constrained Local Neural Fields for robust facial landmark detection in the wild.
//       Tadas Baltrušaitis, Peter Robinson, and Louis-Philippe Morency. 
//       in IEEE Int. Conference on Computer Vision Workshops, 300 Faces in-the-Wild Challenge, 2013.    
//
///////////////////////////////////////////////////////////////////////////////

#include "stdafx.h"

#include "FaceDetectorMTCNN.h"

// OpenCV includes
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc.hpp>

// TBB includes
#include <tbb/tbb.h>

// System includes
#include <fstream>

// Math includes
#define _USE_MATH_DEFINES
#include <cmath>

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

using namespace LandmarkDetector;

// Copy constructor
FaceDetectorMTCNN::FaceDetectorMTCNN(const FaceDetectorMTCNN& other) : PNet(other.PNet), RNet(other.RNet), ONet(other.ONet)
{
}

void ReadMatBin(std::ifstream& stream, cv::Mat &output_mat)
{
	// Read in the number of rows, columns and the data type
	int row, col, type;

	stream.read((char*)&row, 4);
	stream.read((char*)&col, 4);
	stream.read((char*)&type, 4);

	output_mat = cv::Mat(row, col, type);
	int size = output_mat.rows * output_mat.cols * output_mat.elemSize();
	stream.read((char *)output_mat.data, size);

}

void CNN::Read(string location)
{
	ifstream cnn_stream(location, ios::in | ios::binary);
	if (cnn_stream.is_open())
	{
		cnn_stream.seekg(0, ios::beg);

		// Reading in CNNs

		int network_depth;
		cnn_stream.read((char*)&network_depth, 4);

		cnn_layer_types.resize(network_depth);

		for (int layer = 0; layer < network_depth; ++layer)
		{

			int layer_type;
			cnn_stream.read((char*)&layer_type, 4);
			cnn_layer_types[layer] = layer_type;

			// convolutional
			if (layer_type == 0)
			{

				// Read the number of input maps
				int num_in_maps;
				cnn_stream.read((char*)&num_in_maps, 4);

				// Read the number of kernels for each input map
				int num_kernels;
				cnn_stream.read((char*)&num_kernels, 4);

				vector<vector<cv::Mat_<float> > > kernels;
				vector<vector<pair<int, cv::Mat_<double> > > > kernel_dfts;

				kernels.resize(num_in_maps);
				kernel_dfts.resize(num_in_maps);

				vector<float> biases;
				for (int k = 0; k < num_kernels; ++k)
				{
					float bias;
					cnn_stream.read((char*)&bias, 4);
					biases.push_back(bias);
				}

				cnn_convolutional_layers_bias.push_back(biases);

				// For every input map
				for (int in = 0; in < num_in_maps; ++in)
				{
					kernels[in].resize(num_kernels);
					kernel_dfts[in].resize(num_kernels);

					// For every kernel on that input map
					for (int k = 0; k < num_kernels; ++k)
					{
						ReadMatBin(cnn_stream, kernels[in][k]);

					}
				}

				cnn_convolutional_layers.push_back(kernels);
				cnn_convolutional_layers_dft.push_back(kernel_dfts);
			}
			else if (layer_type == 1)
			{
				int kernel_x, kernel_y, stride_x, stride_y;
				cnn_stream.read((char*)&kernel_x, 4);
				cnn_stream.read((char*)&kernel_y, 4);
				cnn_stream.read((char*)&stride_x, 4);
				cnn_stream.read((char*)&stride_y, 4);
				cnn_max_pooling_layers.push_back(std::tuple<int, int, int, int>(kernel_x, kernel_y, stride_x, stride_y));
			}
			else if (layer_type == 2)
			{
				cv::Mat_<float> biases;
				ReadMatBin(cnn_stream, biases);
				cnn_fully_connected_layers_biases.push_back(biases);

				// Fully connected layer
				cv::Mat_<float> weights;
				ReadMatBin(cnn_stream, weights);
				cnn_fully_connected_layers_weights.push_back(weights);
			}

			else if (layer_type == 4)
			{
				cv::Mat_<float> weights;
				ReadMatBin(cnn_stream, weights);
				cnn_prelu_layer_weights.push_back(weights);
			}
		}
	}
	else
	{
		cout << "WARNING: Can't find the CNN location" << endl;
	}
}

//===========================================================================
// Read in the MTCNN detector
void FaceDetectorMTCNN::Read(string location)
{

	cout << "Reading the MTCNN face detector from: " << location << endl;

	ifstream locations(location.c_str(), ios_base::in);
	if (!locations.is_open())
	{
		cout << "Couldn't open the model file, aborting" << endl;
		return;
	}
	string line;

	// The other module locations should be defined as relative paths from the main model
	boost::filesystem::path root = boost::filesystem::path(location).parent_path();

	// The main file contains the references to other files
	while (!locations.eof())
	{
		getline(locations, line);

		stringstream lineStream(line);

		string module;
		string location;

		// figure out which module is to be read from which file
		lineStream >> module;

		lineStream >> location;

		// remove carriage return at the end for compatibility with unix systems
		if (location.size() > 0 && location.at(location.size() - 1) == '\r')
		{
			location = location.substr(0, location.size() - 1);
		}

		// append to root
		location = (root / location).string();
		if (module.compare("PNet") == 0)
		{
			cout << "Reading the PNet module from: " << location << endl;
			PNet.Read(location);
		}
		else if(module.compare("RNet") == 0)
		{
			cout << "Reading the RNet module from: " << location << endl;
			RNet.Read(location);
		}
		else if (module.compare("ONet") == 0)
		{
			cout << "Reading the ONet module from: " << location << endl;
			ONet.Read(location);
		}
	}
}