#ifndef __GPUINITWIRES_CU__
#define __GPUINITWIRES_CU__

#include <stdio.h>

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
using namespace std;

#include <cuda.h>

#include "cutil_math.h"
#include "GPUWire.h"
//-------------------
// GPUInitWires
//-------------------
void GPUInitWires(string fname="gluex_wires.txt")
{
	/// This defines the wire geometry. It does so by reading
	/// the wire parameters in from a text file whose name
	/// is given by the only argument to this function. The
	/// wire definitions are written into an array in device
	/// constant memory using the global symbol "wires_d"
	/// which is defined in GPUWire.h.
	
	// Open wire definitions file
	ifstream file(fname.c_str());
	if(!file.is_open()){
		cout << "Unable to open file \"" << fname << "\"!" << endl;
		exit(-1);
	}
	
	cout << "Reading " << fname << " ..." << endl;
	
	// Read in wire definitions
	int lineno=0;
	vector<Wire> wires; // temporary container used to hold wire definitions
	while(!file.eof()){
		char line[256];
		file.getline(line, 256);
		lineno++;  // keep track of line number in case we need to report error
		if(line[0] == '#') continue;    // skip comment lines
		
		// Read in wire info
		Wire w; // temporary variable
		int N = sscanf(line, "%d %f %f %f %f %f %f %f", &w.id, &w.L, &w.x, &w.y,
		&w.z, &w.i, &w.j, &w.k);
		if(N == 0) continue; // skip empty lines
		if(N < 8 && !file.eof()){
			cout << "Error in file \"" << fname << "\" at line " << lineno << endl;
			cout << "Could not find 8 valid numbers! Exiting now." << endl;
			exit(-1);
		}
		
		// Copy wire parameters into float3 variables
		w.origin = make_float3(w.x, w.y, w.z);
		w.udir = normalize(make_float3(w.i, w.j, w.k));
		
		// not sure if the following is correct ???
		w.sdir = normalize(cross(w.origin, w.udir));
		w.tdir = cross(w.udir, w.sdir);
		
		wires.push_back(w);
	}
	file.close();
	
	cout << "Found " << wires.size() << " wires" << endl;
	
	// We use device constant memory for increased access speed at run time
	// which requires that the memory be pre-allocated for a fixed number of
	// wires using a value known at compile time. Check here that the number
	// of wires read is not more than we preallocated for.
	if(wires.size() > MAX_WIRES){
		cout << "FATAL: The number of wires found in the wire definitions file" << endl;
		cout << "       is greater than number allocated at compile time (" << MAX_WIRES << ")." << endl;
		cout << "       You must edit GPUWire.h and recompile in order to use" <<endl;
		cout << "       the wire definitions in the file \"" << fname << "\"." << endl;
		exit(-1);
	}
	
	// Copy the pointer to the wire definitions in device memory to
	// the "wires_d" symbol so they can be easily accessed from kernels
	// without having to pass in the pointer to every kernel or device call
	size_t size = wires.size() * sizeof(Wire);
	cudaError_t error = cudaMemcpyToSymbol(wires_d, &wires[0], size);
	
}

//-------------------
// GetWire
//-------------------
void GetWire(int idx, Wire &a)
{
	/// This is for debugging purposes. It will copy a Wire structure from
	/// the device constant memory into a Wire structure on the host. The
	/// value of idx is the index of the element to copy and should be between
	/// 0 and MAX_WIRES, though in reality, fewer wires will be defined.

	if(idx<0 || idx>=MAX_WIRES){
		cerr << "ERROR: idx=" << idx << " is out of range! It should" << endl;
		cerr << "       be from 0-" << MAX_WIRES << endl;
		a.id = 0;
		a.L = a.x = a.y = a.z = a.i = a.j = a.k = 0.0;
		return;
	}

	cudaMemcpyFromSymbol(&a, wires_d, sizeof(Wire), idx*sizeof(Wire));
}

//-------------------
// PrintWire
//-------------------
void PrintWire(Wire *tempH)
{
	/// This is for debugging. The tempH pointer should point
	/// to a Wire object in the host memory.

	printf("%d\n", tempH->id);
	printf("%f\n", tempH->x);
	printf("%f\n", tempH->y);
	printf("%f\n", tempH->z);
	printf("%f\n", tempH->i);
	printf("%f\n", tempH->j);
	printf("%f\n", tempH->k);
	printf("%f\n\n", tempH->L);
	//printf("0x%x\n", tempH->ptr);
}
#endif  // __GPUINITWIRES_CU__