#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <ctype.h>		// isspace()
#include <string.h>		// strlen()
#include <GL/gl.h>
#include <vector>
#include <string>
#include <map>
#include <iostream>
#include <fstream>
#include "WFMtl.hh"
using namespace std;

#define WHITESPACE " \n\r\t\v"
#define DEBUGGL

void WFMtl::clear()
{
	m_data = map< string, vector< vector<string> > >();
	m_currentMaterialName = "";
}

int WFMtl::filesize(const char * filename)
{
	struct stat st;
	if (stat(filename, &st))
		return -1;
	return st.st_size;
}

bool WFMtl::load(const string & filename)
{
	clear();

	int size = filesize(filename.c_str());
	if (size < 1)
		return false;

	ifstream ifs(filename.c_str());
	if (!ifs.is_open())
		return false;
	char buf[size+1];

	string buildup;
	while (ifs.good())
	{
		ifs.getline(buf, size+1);
		string input = trim(buf);
		int sz = input.size();
		if (sz == 0 || input[0] == '#')
			continue;
		if (input[sz-1] == '\\')
		{
			input[sz-1] = ' ';
			buildup = input;
			continue;
		}
		if (buildup != "")
			input = buildup + input;
		buildup = "";
		processInputLine(input);
	}

	/* DEBUG */
	map<string, vector< vector<string> > >::iterator it = m_data.begin();
	while (it != m_data.end())
	{
		cout << "Material '" << it->first << "':" << endl;
		for (int i = 0; i < it->second.size(); i++)
		{
			cout << "  ";
			for (int j = 0; j < it->second[i].size(); j++)
			{
				cout << '\'' << it->second[i][j] << "' ";
			}
			cout << endl;
		}
	}
	/* END DEBUG */

	ifs.close();
	return true;
}

string WFMtl::trim(string s)
{
	size_t lastpos = s.find_last_not_of(WHITESPACE);
	if (lastpos == string::npos)
		return "";
	s.erase(lastpos + 1);
	s.erase(0, s.find_first_not_of(WHITESPACE));
	return s;
}

void WFMtl::processInputLine(const std::string & input)
{
	string line = input;
	vector<string> lineParts;
	for (;;)
	{
		string token = stripFirstToken(line);
		if (token == "")
			break;
		lineParts.push_back(token);
	}
	if (lineParts.size() > 0)
	{
		if ( (lineParts.size() >= 2) && (lineParts[0] == "newmtl") )
		{
			m_currentMaterialName = lineParts[1];
		}
		else if (m_currentMaterialName != "")
		{
			m_data[m_currentMaterialName].push_back(lineParts);
		}
	}
}

string WFMtl::stripFirstToken(string & input)
{
	size_t firstnonspace = input.find_first_not_of(WHITESPACE);
	if (firstnonspace == string::npos)
		return "";
	size_t spaceafter = input.find_first_of(WHITESPACE, firstnonspace);
	string token = input.substr(firstnonspace, spaceafter - firstnonspace);
	input.erase(0, spaceafter);
	return token;
}

void WFMtl::render()
{
}