import java.io.IOException;
import java.util.Arrays;
import java.util.concurrent.TimeUnit;


// todo: add Dokumentation
public class gpio_java 
{
	public static String rel_map [][] = {
										{"rel1","14"}, 
										{"rel2","15"},
										{"rel3","18"},
										{"rel4","23"},
										{"rel5","24"},
										{"rel6","25"},
										{"rel7","8"},
										{"rel8","7"}
										};	
	public static String [] action = {"on", "off", "status"};

	public static void main (String [] args) 
	{
		// Zum checken der Anzahl der Argumente
		checkargs(args);
		
		// todo: initialisiere alle acht ports (outputs)
		init_gpio();
		
		// setze gpio (gemaes der parameter)
		gpio_getport(args[0]);
		
		
		gpio_cmdhandler(args[0], args[1]);
		
		// todo: remove following not used code
		/*
		setgpio(true);
		
		try {
			TimeUnit.SECONDS.sleep(1);
		}
		catch(InterruptedException e) 
		{
			System.out.println("sleep error InterruptedException ocure");	
		}
		
		setgpio(false);
        */
	}
	
	public static void checkargs(String[] argumens)
	{
		int laenge = argumens.length;
		String [] h = {"-h"};
		int idx;
		boolean parameter1 = false;
		boolean parameter2 = false;

		
		if (laenge == 2)
		{
			//ToDO: Pruefe erstes und zweites Argument
			//Erstes Element(rel)
			for (idx = 0; idx<8 ; idx++)
			{
				if (argumens[0].equals(rel_map[idx][0]))
				{
					parameter1 = true;
					break;
				}
			}
			//Zweites Element (action)
			for (idx = 0; idx<3 ; idx++)
			{
				if (argumens[1].equals(action[idx]))
				{
					parameter2 = true;
					break;
				}
			}
			
		}
		else if (Arrays.equals (argumens, h) == true)
		{
			
			show_usage();
			
			System.exit(0);
		}
		else
		{
			System.out.println("Error. If you need help, type the command -h");
			
			System.exit(0);
		}
		//ToDo: Return

	}
	
	public static void init_gpio()
	{
		int idx;
		String port;
		String cmd;
		
		for(idx = 0; idx<8 ; idx++)
		{
			port = rel_map[idx][1];
			cmd = "/usr/bin/gpio -g mode " + port + " out";
			launchcmd(cmd);
			
		}
		return;
	}
	
	public static int gpio_getport(String port)
	{	
		int idx;
		
		for(idx = 0; idx<8 ; idx++)
		{
			if(port.equals(rel_map[idx][0]))
			{
				return idx;
			}
		}
		
		return -1;
	}
	
	public static int gpio_cmdhandler(String port, String cmd)
	{
		int idx_port;
		
		idx_port = gpio_getport(port);

		
		if (cmd.equals(action [0]))
		{
			//Schalte on
			cmd = "/usr/bin/gpio -g write " + rel_map[idx_port][1] + " 1";
			launchcmd(cmd);
			
		}
		if (cmd.equals(action [1]))
		{
			//Schalte off
			cmd = "/usr/bin/gpio -g write " + rel_map[idx_port][1] + " 0";
			launchcmd(cmd);
		}
		/*if (cmd.equals(action [2]))
		{
			//Stats geben
			cmd = "/usr/bin/gpio -g write " + port + status();
			launchcmd(cmd);
		}*/
		return -1;
	}
	
	public static void show_usage()
	{
		System.out.println("You have to enter exactly 2 arguments.");
		System.out.println("Example: java gpio_java Argument1 Argument2");
		System.out.println("Argument1: rel1, rel2, rel3, ..., rel8");
		System.out.println("Argument2: on,off or status");
	}
	
	public static void launchcmd(String cmd) 
	{
		// Wenn Simulation True ist kann sie auf dem PC ausfuehren
		// wenn die Simulation false is auf dem Raspberry PI
		boolean simulation = false;
		
		if(simulation==true){
			System.out.println(cmd);	
		} 
		else {
			try{
				Runtime.getRuntime().exec(cmd);
			}
			catch(IOException e)
			{
				System.out.println("process error IOException");					
			}
		}
	}
	
	
	public static void setgpio(boolean status) 
	{
		launchcmd("/usr/bin/gpio -g mode 14 out");
		
		if(status == true) 
		{
			launchcmd("/usr/bin/gpio -g write 14 1");
		}
		else 
		{
			launchcmd("/usr/bin/gpio -g write 14 0");
		}
	}
	
	
}