/*
*	Copyright (C) 2012 Thorsten Liebig (Thorsten.Liebig@gmx.de)
*
*	This program is free software: you can redistribute it and/or modify
*	it under the terms of the GNU General Public License as published by
*	the Free Software Foundation, either version 3 of the License, or
*	(at your option) any later version.
*
*	This program is distributed in the hope that it will be useful,
*	but WITHOUT ANY WARRANTY; without even the implied warranty of
*	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*	GNU General Public License for more details.
*
*	You should have received a copy of the GNU General Public License
*	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "nf2ff_calc.h"
#include "../tools/array_ops.h"
#include "../tools/useful.h"

#include <stdio.h>
#include <stdlib.h>
#include <vector>
#include <cmath>
#include <complex>
#include <iostream>
#include <sstream>

nf2ff_calc_thread::nf2ff_calc_thread(nf2ff_calc* nfc, unsigned int start, unsigned int stop, unsigned int threadID, nf2ff_data &data)
{
	m_nf_calc = nfc;
	m_start = start;
	m_stop = stop;
	m_threadID = threadID;
	m_data = data;
}

void nf2ff_calc_thread::operator()()
{
	m_nf_calc->m_Barrier->wait(); // start

	int ny = m_data.ny;
	int nP = (ny+1)%3;
	int nPP = (ny+2)%3;

	unsigned int* numLines = m_data.numLines;
	float* normDir = m_data.normDir;
	float **lines = m_data.lines;
	float* edge_length_P = m_data.edge_length_P;
	float* edge_length_PP = m_data.edge_length_PP;

	unsigned int pos[3];
	unsigned int pos_t=0;
	unsigned int num_t=m_stop-m_start+1;


	complex<float>**** Js=m_data.Js;
	complex<float>**** Ms=m_data.Ms;
	complex<float>**** E_field=m_data.E_field;
	complex<float>**** H_field=m_data.H_field;

	// calc Js and Ms (eq. 8.15a/b)
	pos[ny]=0;
	for (pos_t=0; pos_t<num_t; ++pos_t)
	{
		pos[nP] = m_start+pos_t;
		for (pos[nPP]=0; pos[nPP]<numLines[nPP]; ++pos[nPP])
			{
				// Js =  n x H
				Js[0][pos[0]][pos[1]][pos[2]] = normDir[1]*H_field[2][pos[0]][pos[1]][pos[2]] - normDir[2]*H_field[1][pos[0]][pos[1]][pos[2]];
				Js[1][pos[0]][pos[1]][pos[2]] = normDir[2]*H_field[0][pos[0]][pos[1]][pos[2]] - normDir[0]*H_field[2][pos[0]][pos[1]][pos[2]];
				Js[2][pos[0]][pos[1]][pos[2]] = normDir[0]*H_field[1][pos[0]][pos[1]][pos[2]] - normDir[1]*H_field[0][pos[0]][pos[1]][pos[2]];

				// Ms = -n x E
				Ms[0][pos[0]][pos[1]][pos[2]] = normDir[2]*E_field[1][pos[0]][pos[1]][pos[2]] - normDir[1]*E_field[2][pos[0]][pos[1]][pos[2]];
				Ms[1][pos[0]][pos[1]][pos[2]] = normDir[0]*E_field[2][pos[0]][pos[1]][pos[2]] - normDir[2]*E_field[0][pos[0]][pos[1]][pos[2]];
				Ms[2][pos[0]][pos[1]][pos[2]] = normDir[1]*E_field[0][pos[0]][pos[1]][pos[2]] - normDir[0]*E_field[1][pos[0]][pos[1]][pos[2]];
			}
	}

	complex<float>** m_Nt=m_data.m_Nt;
	complex<float>** m_Np=m_data.m_Np;
	complex<float>** m_Lt=m_data.m_Lt;
	complex<float>** m_Lp=m_data.m_Lp;

	// calc local Nt,Np,Lt and Lp
	float area;
	float cosT_cosP,cosP_sinT;
	float cosT_sinP,sinT_sinP;
	float sinT,sinP;
	float cosP,cosT;
	float r_cos_psi;
	float k = 2*M_PI*m_nf_calc->m_freq/__C0__;
	complex<float> exp_jkr;
	complex<float> _I_(0,1);
	for (unsigned int tn=0;tn<m_nf_calc->m_numTheta;++tn)
		for (unsigned int pn=0;pn<m_nf_calc->m_numPhi;++pn)
		{
			sinT = sin(m_nf_calc->m_theta[tn]);
			sinP = sin(m_nf_calc->m_phi[pn]);
			cosT = cos(m_nf_calc->m_theta[tn]);
			cosP = cos(m_nf_calc->m_phi[pn]);
			cosT_cosP = cosT*cosP;
			cosT_sinP = cosT*sinP;
			cosP_sinT = cosP*sinT;
			sinT_sinP = sinP*sinT;

			for (pos_t=0; pos_t<num_t; ++pos_t)
			{
				pos[nP] = m_start+pos_t;
				for (pos[nPP]=0; pos[nPP]<numLines[nPP]; ++pos[nPP])
					{
						r_cos_psi = lines[0][pos[0]]*cosP_sinT + lines[1][pos[1]]*sinT_sinP + lines[2][pos[2]]*cosT;
						exp_jkr = exp(_I_*k*r_cos_psi);
						area = edge_length_P[pos[nP]]*edge_length_PP[pos[nPP]];
						m_Nt[tn][pn] += area*exp_jkr*(Js[0][pos[0]][pos[1]][pos[2]]*cosT_cosP + Js[1][pos[0]][pos[1]][pos[2]]*cosT_sinP \
													- Js[2][pos[0]][pos[1]][pos[2]]*sinT);
						m_Np[tn][pn] += area*exp_jkr*(Js[1][pos[0]][pos[1]][pos[2]]*cosP - Js[0][pos[0]][pos[1]][pos[2]]*sinP);

						m_Lt[tn][pn] += area*exp_jkr*(Ms[0][pos[0]][pos[1]][pos[2]]*cosT_cosP + Ms[1][pos[0]][pos[1]][pos[2]]*cosT_sinP \
													- Ms[2][pos[0]][pos[1]][pos[2]]*sinT);
						m_Lp[tn][pn] += area*exp_jkr*(Ms[1][pos[0]][pos[1]][pos[2]]*cosP - Ms[0][pos[0]][pos[1]][pos[2]]*sinP);
					}

			}
		}

	m_nf_calc->m_Barrier->wait(); //combine all thread local Nt,Np,Lt and Lp

	m_nf_calc->m_Barrier->wait(); //wait for termination
}


/***********************************************************************/


nf2ff_calc::nf2ff_calc(float freq, vector<float> theta, vector<float> phi)
{
	m_freq = freq;

	m_numTheta = theta.size();
	m_theta = new float[m_numTheta];
	for (size_t n=0;n<m_numTheta;++n)
		 m_theta[n]=theta.at(n);

	m_numPhi = phi.size();
	m_phi = new float[m_numPhi];
	for (size_t n=0;n<m_numPhi;++n)
		 m_phi[n]=phi.at(n);

	unsigned int numLines[2] = {m_numTheta, m_numPhi};
	m_E_theta = Create2DArray<std::complex<float> >(numLines);
	m_E_phi = Create2DArray<std::complex<float> >(numLines);
	m_H_theta = Create2DArray<std::complex<float> >(numLines);
	m_H_phi = Create2DArray<std::complex<float> >(numLines);
	m_P_rad = Create2DArray<float>(numLines);

	m_centerCoord[0]=m_centerCoord[1]=m_centerCoord[2]=0;

	m_radPower = 0;
	m_maxDir = 0;
	m_radius = 1;

	m_Barrier = NULL;
	m_numThreads = boost::thread::hardware_concurrency();
}

nf2ff_calc::~nf2ff_calc()
{
	delete[] m_phi;
	m_phi = NULL;
	delete[] m_theta;
	m_theta = NULL;

	unsigned int numLines[2] = {m_numTheta, m_numPhi};
	Delete2DArray(m_E_theta,numLines);
	m_E_theta = NULL;
	Delete2DArray(m_E_phi,numLines);
	m_E_phi = NULL;
	Delete2DArray(m_H_theta,numLines);
	m_H_theta = NULL;
	Delete2DArray(m_H_phi,numLines);
	m_H_phi = NULL;
	Delete2DArray(m_P_rad,numLines);
	m_P_rad = NULL;

	delete m_Barrier;
	m_Barrier = NULL;
}

bool nf2ff_calc::AddPlane(float **lines, unsigned int* numLines, complex<float>**** E_field, complex<float>**** H_field)
{
	//find normal direction
	int ny = -1;
	int nP,nPP;
	for (int n=0;n<3;++n)
	{
		nP = (n+1)%3;
		nPP = (n+2)%3;
		if ((numLines[n]==1) && (numLines[nP]>2) && (numLines[nPP]>2))
			ny=n;
	}
	nP = (ny+1)%3;
	nPP = (ny+2)%3;
	if (ny<0)
	{
		cerr << "nf2ff_calc::AddPlane: Error can't determine normal direction..." << endl;
		return false;
	}

	complex<float>**** Js = Create_N_3DArray<complex<float> >(numLines);
	complex<float>**** Ms = Create_N_3DArray<complex<float> >(numLines);

	float normDir[3]= {0,0,0};
	if (lines[ny][0]>=m_centerCoord[ny])
		normDir[ny]=1;
	else
		normDir[ny]=-1;
	unsigned int pos[3];

	float edge_length_P[numLines[nP]];
	for (unsigned int n=1;n<numLines[nP]-1;++n)
		edge_length_P[n]=0.5*(lines[nP][n+1]-lines[nP][n-1]);
	edge_length_P[0]=0.5*(lines[nP][1]-lines[nP][0]);
	edge_length_P[numLines[nP]-1]=0.5*(lines[nP][numLines[nP]-1]-lines[nP][numLines[nP]-2]);

	float edge_length_PP[numLines[nPP]];
	for (unsigned int n=1;n<numLines[nPP]-1;++n)
		edge_length_PP[n]=0.5*(lines[nPP][n+1]-lines[nPP][n-1]);
	edge_length_PP[0]=0.5*(lines[nPP][1]-lines[nPP][0]);
	edge_length_PP[numLines[nPP]-1]=0.5*(lines[nPP][numLines[nPP]-1]-lines[nPP][numLines[nPP]-2]);

	complex<float> power = 0;
	float area;
	for (pos[0]=0; pos[0]<numLines[0]; ++pos[0])
		for (pos[1]=0; pos[1]<numLines[1]; ++pos[1])
			for (pos[2]=0; pos[2]<numLines[2]; ++pos[2])
			{
				area = edge_length_P[pos[nP]]*edge_length_PP[pos[nPP]];
				power = (E_field[nP][pos[0]][pos[1]][pos[2]]*conj(H_field[nPP][pos[0]][pos[1]][pos[2]]) \
							- E_field[nPP][pos[0]][pos[1]][pos[2]]*conj(H_field[nP][pos[0]][pos[1]][pos[2]]));
				m_radPower += 0.5*area*real(power)*normDir[ny];
			}

	unsigned int numAngles[2] = {m_numTheta, m_numPhi};

	// setup multi-threading jobs
	vector<unsigned int> jpt = AssignJobs2Threads(numLines[nP], m_numThreads, true);
	m_numThreads = jpt.size();
	nf2ff_data thread_data[m_numThreads];
	m_Barrier = new boost::barrier(m_numThreads+1); // numThread workers + 1 controller
	unsigned int start=0;
	unsigned int stop=jpt.at(0)-1;
	for (unsigned int n=0; n<m_numThreads; n++)
	{
		thread_data[n].ny=ny;
		thread_data[n].normDir=normDir;
		thread_data[n].numLines=numLines;
		thread_data[n].lines=lines;
		thread_data[n].edge_length_P=edge_length_P;
		thread_data[n].edge_length_PP=edge_length_PP;
		thread_data[n].E_field=E_field;
		thread_data[n].H_field=H_field;
		thread_data[n].Js=Js;
		thread_data[n].Ms=Ms;
		thread_data[n].m_Nt=Create2DArray<complex<float> >(numAngles);
		thread_data[n].m_Np=Create2DArray<complex<float> >(numAngles);
		thread_data[n].m_Lt=Create2DArray<complex<float> >(numAngles);
		thread_data[n].m_Lp=Create2DArray<complex<float> >(numAngles);

		boost::thread *t = new boost::thread( nf2ff_calc_thread(this,start,stop,n,thread_data[n]) );

		m_thread_group.add_thread( t );

		start = stop+1;
		if (n<m_numThreads-1)
			stop = start + jpt.at(n+1)-1;
	}
	//all threads a running and waiting for the barrier

	m_Barrier->wait(); //start

	// threads: calc Js and Ms (eq. 8.15a/b)
	// threads calc their local Nt,Np,Lt and Lp

	m_Barrier->wait(); //combine all thread local Nt,Np,Lt and Lp

	//cleanup E- & H-Fields
	Delete_N_3DArray(E_field,numLines);
	Delete_N_3DArray(H_field,numLines);

	complex<float>** Nt = Create2DArray<complex<float> >(numAngles);
	complex<float>** Np = Create2DArray<complex<float> >(numAngles);
	complex<float>** Lt = Create2DArray<complex<float> >(numAngles);
	complex<float>** Lp = Create2DArray<complex<float> >(numAngles);

	for (unsigned int n=0; n<m_numThreads; n++)
	{
		for (unsigned int tn=0;tn<m_numTheta;++tn)
			for (unsigned int pn=0;pn<m_numPhi;++pn)
			{
				Nt[tn][pn] += thread_data[n].m_Nt[tn][pn];
				Np[tn][pn] += thread_data[n].m_Np[tn][pn];
				Lt[tn][pn] += thread_data[n].m_Lt[tn][pn];
				Lp[tn][pn] += thread_data[n].m_Lp[tn][pn];
			}
		Delete2DArray(thread_data[n].m_Nt,numAngles);
		Delete2DArray(thread_data[n].m_Np,numAngles);
		Delete2DArray(thread_data[n].m_Lt,numAngles);
		Delete2DArray(thread_data[n].m_Lp,numAngles);
	}

	m_Barrier->wait(); //wait for termination
	m_thread_group.join_all(); // wait for termination
	delete m_Barrier;
	m_Barrier = NULL;

	//cleanup Js & Ms
	Delete_N_3DArray(Js,numLines);
	Delete_N_3DArray(Ms,numLines);

	// calc equations 8.23a/b and 8.24a/b
	float k = 2*M_PI*m_freq/__C0__;
	complex<float> factor(0,k/4.0/M_PI/m_radius);
	complex<float> f_exp(0,-1*k*m_radius);
	factor *= exp(f_exp);
	complex<float> Z0 = __Z0__;
	float P_max = 0;
	for (unsigned int tn=0;tn<m_numTheta;++tn)
		for (unsigned int pn=0;pn<m_numPhi;++pn)
		{
			m_E_theta[tn][pn] -= factor*(Lp[tn][pn] + Z0*Nt[tn][pn]);
			m_E_phi[tn][pn] += factor*(Lt[tn][pn] - Z0*Np[tn][pn]);

			m_H_theta[tn][pn] += factor*(Np[tn][pn] - Lt[tn][pn]/Z0);
			m_H_phi[tn][pn] -= factor*(Nt[tn][pn] + Lp[tn][pn]/Z0);

			m_P_rad[tn][pn] = m_radius*m_radius/(2*__Z0__) * abs((m_E_theta[tn][pn]*conj(m_E_theta[tn][pn])+m_E_phi[tn][pn]*conj(m_E_phi[tn][pn])));
			if (m_P_rad[tn][pn]>P_max)
				P_max = m_P_rad[tn][pn];
		}

	//cleanup Nx and Lx
	Delete2DArray(Nt,numAngles);
	Delete2DArray(Np,numAngles);
	Delete2DArray(Lt,numAngles);
	Delete2DArray(Lp,numAngles);

	m_maxDir = 4*M_PI*P_max / m_radPower;

	return true;
}