/********************************************************
 *  ██████╗  ██████╗████████╗██╗
 * ██╔════╝ ██╔════╝╚══██╔══╝██║
 * ██║  ███╗██║        ██║   ██║
 * ██║   ██║██║        ██║   ██║
 * ╚██████╔╝╚██████╗   ██║   ███████╗
 *  ╚═════╝  ╚═════╝   ╚═╝   ╚══════╝
 * Geophysical Computational Tools & Library (GCTL)
 *
 * Copyright (c) 2022  Yi Zhang (yizhang-geo@zju.edu.cn)
 *
 * GCTL is distributed under a dual licensing scheme. You can redistribute 
 * it and/or modify it under the terms of the GNU Lesser General Public 
 * License as published by the Free Software Foundation, either version 2 
 * of the License, or (at your option) any later version. You should have 
 * received a copy of the GNU Lesser General Public License along with this 
 * program. If not, see <http://www.gnu.org/licenses/>.
 * 
 * If the terms and conditions of the LGPL v.2. would prevent you from using 
 * the GCTL, please consider the option to obtain a commercial license for a 
 * fee. These licenses are offered by the GCTL's original author. As a rule, 
 * licenses are provided "as-is", unlimited in time for a one time fee. Please 
 * send corresponding requests to: yizhang-geo@zju.edu.cn. Please do not forget 
 * to include some description of your company and the realm of its activities. 
 * Also add information on how to contact you by electronic and paper mail.
 ******************************************************/

#include "gctl/core.h"
#include "gctl/io.h"
#include "gctl/utility.h"

int main(int argc, char *argv[]) try
{
	gctl::flags_parser fp;
	fp.set_proname("sph2plane");
	fp.set_proinfo("Project spherical data points to a plane surface with respected to \
a reference point. This program is a toolkit of the GCTL package. The GCTL comes with ABSOLUTE NO WARRANTY. \
Please see instructions or contact the author for more information. The program \
takes inputs from the standard input and display the results on screen. The coordinates \
should be separated by spaces and different points should be placed on different lines. \
The inputting continues until encounter a blank line or 'EOF'. Any lines start with '#' will be skipped.");

	fp.add_opt('a', "anchor", required_argument, NULL,
		"The reference point (anchor) for the project.", "<lon>,<lat>", true);
	fp.add_opt('r', "reference", required_argument, NULL, 
		"Set a reference system for converting the coordinates according to the specified spherical or ellipsoidal surface.", "<r>/<R>|<f>,<R>|WGS84|Earth|Moon", true);
	fp.add_opt('u', "unit-length", no_argument, NULL,
		"Use the unit-length at the reference point to project all data points. This is often required to get unified intervals for grid data points.", 0, false);
	fp.add_opt('c', "column", required_argument, NULL, 
		"Select data columns for the longitudinal and latitudinal coordinates (the default is 0,1).", "<lon-col>,<lat-col>", false);
	fp.add_opt('p', "precision", required_argument, NULL, 
		"Set the precision of the outputs (the default is 12).", "<precision>", false);
	fp.add_opt('h', "help", no_argument, NULL, "Show help information.", 0, false);
	fp.configure(argc, argv);

	if(argc == 1 || fp.set_opt('h'))
	{
		fp.show_help_page();
		return 0;
	}

	// 查看是否通过强制参数检查
	if (!fp.pass_mandatory()) return 0;

	bool use_unit = false;
	if (fp.set_opt('u'))
	{
		use_unit = true;
	}

	std::string err_str, anchor_str, ref_str, col_str, pre_str;
	std::stringstream tmp_ss;

	fp.get_argv({'a', 'r', 'c', 'p'}, {&anchor_str, &ref_str, &col_str, &pre_str});
	// 确定参考点
	double ref_lon = -200.0, ref_lat = -100.0;
	if (2 != sscanf(anchor_str.c_str(), "%lf,%lf", &ref_lon, &ref_lat) || 
		ref_lon < -180.0 || ref_lon > 180.0 || ref_lat < -90.0 || ref_lat > 90.0)
	{
		err_str = "Wrong entrance: " + anchor_str;
		throw err_str;
	}

	// 确定参考球
	double ref_r, ref_R;
	if (ref_str == "WGS84")
	{
		ref_r = GCTL_WGS84_PoleRadius;
		ref_R = GCTL_WGS84_EquatorRadius;
	}
	else if (ref_str == "Earth")
	{
		ref_r = GCTL_Earth_Radius;
		ref_R = GCTL_Earth_Radius;
	}
	else if (ref_str == "Moon")
	{
		ref_r = GCTL_Moon_Radius;
		ref_R = GCTL_Moon_Radius;
	}
	else if (2 != sscanf(ref_str.c_str(), "%lf/%lf", &ref_r, &ref_R))
	{
		if (2 == sscanf(ref_str.c_str(), "%lf,%lf", &ref_r, &ref_R))
		{
				ref_r = (1.0-ref_r)*ref_R;
		}
		else
		{
			err_str = "Wrong entrance: " + ref_str;
			throw err_str;
		}
	}

	// 确定坐标列
	int col_lon, col_lat;
	if (col_str == "NULL") col_str = "0,1";
	if (2 != sscanf(col_str.c_str(), "%d,%d", &col_lon, &col_lat))
	{
		err_str = "Wrong entrance: " + col_str;
		throw err_str;
	}

	// 确定输出精度
	int pre_int;
	if (pre_str == "NULL") pre_str = "12";
	if (1 != sscanf(pre_str.c_str(), "%d", &pre_int))
	{
		err_str = "Wrong entrance: " + pre_str;
		throw err_str;
	}

	std::string line;
	std::vector<std::string> line_arr;
	std::vector<double> line_ele;
	gctl::point3dc pc;
	gctl::point3ds ps;
	while (true)
	{
		std::getline(std::cin, line);
		if (line[0] == '#') continue;
		if (line.empty() || line == "EOF") break;
		else line_arr.push_back(line);
	}

	std::cout << "# Outputs from the sph2plane. Use -h to see the help information." << std::endl;
	std::cout << "# reference system: " << ref_str << std::endl;
	std::cout << "# reference coordinate: lon = " << ref_lon << ", lat = " << ref_lat << std::endl;

	double rad, rad_lat, unit_yl, unit_xl, tmp_d;
	double point_lon, point_lat;
	if (use_unit)
	{
		// 计算参考点处的经纬向单位长度
		rad = gctl::ellipse_radius_2d(ref_R, ref_r, ref_lat*GCTL_Pi/180.0);
		unit_yl = rad*tan(1.0*GCTL_Pi/180.0);

		rad_lat = rad*sin(GCTL_Pi*(90.0 - ref_lat)/180.0);
		unit_xl = rad_lat*tan(1.0*GCTL_Pi/180.0);

		for (int i = 0; i < line_arr.size(); i++)
		{
			if (!line_ele.empty()) line_ele.clear();

			tmp_ss.clear();
			tmp_ss.str(line_arr[i]);
			while (tmp_ss.good())
			{
				tmp_ss >> tmp_d;
				line_ele.push_back(tmp_d);
			}

			if (line_ele.size() <= GCTL_MAX(col_lon, col_lat))
			{
				err_str = "Wrong entrance: " + line_arr[i];
				throw err_str;
			}

			point_lon = line_ele[col_lon];
			point_lat = line_ele[col_lat];

			line_ele[col_lon] = (point_lon - ref_lon)*unit_xl;
			line_ele[col_lat] = (point_lat - ref_lat)*unit_yl;

			std::cout << std::setprecision(pre_int) << line_ele[0];
			for (int l = 1; l < line_ele.size(); l++)
			{
				std::cout << std::setprecision(pre_int) << " " << line_ele[l];
			}
			std::cout << std::endl;
		}
	}
	else
	{
		for (int i = 0; i < line_arr.size(); i++)
		{
			if (!line_ele.empty()) line_ele.clear();

			tmp_ss.clear();
			tmp_ss.str(line_arr[i]);
			while (tmp_ss.good())
			{
				tmp_ss >> tmp_d;
				line_ele.push_back(tmp_d);
			}

			if (line_ele.size() <= GCTL_MAX(col_lon, col_lat))
			{
				err_str = "Wrong entrance: " + line_arr[i];
				throw err_str;
			}

			point_lon = line_ele[col_lon];
			point_lat = line_ele[col_lat];

			// 计算参考点处的经纬向单位长度
			rad = gctl::ellipse_radius_2d(ref_R, ref_r, ref_lat*GCTL_Pi/180.0);
			rad_lat = rad*sin(GCTL_Pi*(90.0 - ref_lat)/180.0);

			line_ele[col_lat] = rad*tan((point_lat - ref_lat)*GCTL_Pi/180.0);
			line_ele[col_lon] = rad_lat*tan((point_lon - ref_lon)*GCTL_Pi/180.0);

			std::cout << std::setprecision(pre_int) << line_ele[0];
			for (int l = 1; l < line_ele.size(); l++)
			{
				std::cout << std::setprecision(pre_int) << " " << line_ele[l];
			}
			std::cout << std::endl;
		}
	}
	return 0;
}
catch(std::exception &e)
{
	GCTL_ShowWhatError(e.what(), GCTL_ERROR_ERROR, 0, 0, 0);
}