package urt;

import java.text.DecimalFormat;

public class xytoutm {

	static DecimalFormat df = new DecimalFormat("0.0000000");

	/**½«dx,dyתΪ¾­Î³¶È¸ß³Ì·µ»Ødouble[]·µ»ØµÄ½á¹ûÊǶȷָñʽµÄ
	 * a[0]¾­¶È¶È¸ñʽ
	 * a[1]ά¶È¶È¸ñʽ
	 * a[2]¾­¶È¶È·Ö¸ñʽ
	 * a[3]¾­¶È¶È·Ö¸ñʽ*/
	public static String[] xy2jwd(String dx,String dy,double[] xycs) {
		String xy2jwd[]=new String[4];	
		double x=Double.valueOf(dx);
		double y=Double.valueOf(dy);
		x=x/100;
		y=y/100;
		double utme0=xycs[0];
		double utmn0=xycs[1];
		double c=xycs[2];
		double s=xycs[3];
		double f=xycs[5];
		double[] utm = xyutm(x,y,utme0, utmn0,c,s);
		double jwd[]= utm2ll_wgs84(utm[0],utm[1],f);
		xy2jwd[0]=String.valueOf(df.format(jwd[0]));
		xy2jwd[1]=String.valueOf(df.format(jwd[1]));
		jwd[0]=xytognss.ublox_d2dm(jwd[0]);
		jwd[1]=xytognss.ublox_d2dm(jwd[1]);
		xy2jwd[2]=String.valueOf(df.format(jwd[0]));
		xy2jwd[3]=String.valueOf(df.format(jwd[1]));
		return xy2jwd;
	}

	/**xÊÇÐèҪת»»µÄ
	 * yÐèҪת»»µÄ
	 * utme0³õʼ»¯µÄʱºò»ñµÃµÄÊý¾Ý*/
	public static double[] xyutm(double x,double y,double utme0, double utmn0,double c, double s) {
		double[] utm=new double[2];
		double x1, y1, dx, dy, utme, utmn;
		x1=y; y1=x;
		dx = c*x1 + s*y1;
		dy = -s*x1 + c*y1;
		utme = dx + utme0;
		utmn = dy + utmn0;
		utm[0] = utme;
		utm[1] = utmn;
		return utm;
	}

	// function [lat,lon]=utm2ll_wgs84(x,y,f)
	public static double[] utm2ll_wgs84(double x,double y,double f) {
		double[] latlon = new double[2];
		double A1 = 6378137.0;
		double F1 = 298.257223563;

		// constants
		double D0 = 180/Math.PI;	
		double maxiter = 100;	
		double eps = 1e-11;	

		double K0 = 0.9996;								
		double X0 = 500000;								
		// double Y0 = 1e7*(f < 0);
		double Y0 = 0;
		if(f < 0){
			Y0 = 1e7;
		}					
		double P0 = 0;										
		double L0 = (6*Math.abs(f) - 183)/D0;					
		double E1 = Math.sqrt(( A1*A1 - (A1*(1 - 1/F1))*(A1*(1 - 1/F1)))/(A1*A1));	
		double N = K0*A1;

		double[] C = coef(E1,0);
		double YS = Y0 - N*(C[0]*P0 + C[1]*Math.sin(2*P0) + C[2]*Math.sin(4*P0) +
				C[3]*Math.sin(6*P0) + C[4]*Math.sin(8*P0));

		C = coef(E1,1);
		double zta = (y - YS)/N/C[0];
		double ztb = (x - X0)/N/C[0];
		double L = zta;
		double LS = ztb;
		// for i = 2:5
		for(int i = 2; i < 6; i++)
		{
			double zta_temp = zta*(i-1)*2;
			double ztb_temp = ztb*(i-1)*2;
			L = L - C[i-1]*Math.sin(zta_temp)*Math.cosh(ztb_temp);
			LS = LS - C[i-1]*Math.cos(zta_temp)*Math.sinh(ztb_temp);
		}

		double l = L0 + Math.atan(Math.sinh(LS)/Math.cos(L));
		double p = Math.asin(Math.sin(L)/Math.cosh(LS));

		L = Math.log(Math.tan(Math.PI/4 + p/2));

		p = 2*Math.atan(Math.exp(L)) - Math.PI/2;
		double p0 = 0;
		double n = 0;
		while ((p0==0 || Math.abs(p - p0) > eps) && n < maxiter) {
			p0 = p;
			double es = E1*Math.sin(p0);
			p = 2*Math.atan(Math.pow((1 + es)/(1 - es), E1/2)*Math.exp(L)) - Math.PI/2;
			n = n + 1;
		}
		latlon[0] = p*D0;
		latlon[1] = l*D0;
		return latlon;
	}

	//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
	// function c = coef(e,m)
	public static double[] coef(double e,int m) {
		double[][] c0;
		double[] c = new double[5];
		// switch m
		// case 0
		if (m==0) {
			c0 = new double[][] {
				{-175.0/16384.0,0.0,   -5/256.0, 0.0,  -3/64.0, 0.0, -1/4.0, 0.0, 1.0},
				{-105/4096.0,   0.0, -45/1024.0, 0.0,  -3/32.0, 0.0, -3/8.0, 0.0, 0.0},
				{525 /16384.0,  0.0,  45/1024.0, 0.0, 15/256.0, 0.0,    0.0, 0.0, 0.0},
				{-175/12288.0,  0.0, -35/3072.0, 0.0,      0.0, 0.0,    0.0, 0.0, 0.0},
				{315 /131072.0, 0.0,        0.0, 0.0,      0.0, 0.0,    0.0, 0.0, 0.0} // 5x9
			};
		}
		else {
			c0 = new double[][] {
				{-175/16384.0,   0.0,   -5/256.0, 0.0,  -3/64.0, 0.0, -1/4.0, 0.0, 1.0},
				{   1/61440.0,   0.0,   7/2048.0, 0.0,   1/48.0, 0.0,  1/8.0, 0.0, 0.0},
				{ 59/368640.0,   0.0,   3/1280.0, 0.0,  1/768.0, 0.0,    0.0, 0.0, 0.0},
				{ 283/430080.0,  0.0, 17/30720.0, 0.0,      0.0, 0.0,    0.0, 0.0, 0.0},
				{4397/41287680.0, 0.0,       0.0, 0.0,      0.0, 0.0,    0.0, 0.0, 0.0} // 5x9
			};
		}
		for(int i =1; i < 6; i++)
		{
			for(int j =1; j < 10; j++)
			{
				c[i-1] = c[i-1] + c0[i-1][j-1]*Math.pow(e, 9-j);
			}
		}
		return c;
	}


}