package affectors;

import main.Node;
import main.Globals;

/** This affector returns a constant value to cause the target node to go to
 * the specified final value (Final) when coupled to constant linear decay.
 * The rate of decay is needed for scaling with the nondimensionalization.
 *
 * <p> <b>Formula</b>
 * <br>dNODEX/dt = Final/H_Nodex
 *
 * <p> <b>Parameters</b>
 * <table width="500" border="1">
 * <tr><td width="150">Half life [H_Nodex]</td><td> The half life of the target node.</td></tr>
 * <tr><td width="150">Final level [Final]</td><td> The final concentration of the target assuming constant linear degredation.</td></tr>
 * </table>
 *
 * <p><b>Usage</b>
 * <code><font size = "3"><br>&Nodex
 * <blockquote>	&ConstantLevelAff	H_nodex Final
 * </blockquote>
 * &endnodex</code></font>
 *
 * @author Josselin Milloz
 * @see ConstantInputAff
*/
public class ConstantLevelAff extends Affector	{
	/** The value returned by this affector. */
	int		halflifeparam;
	int 	finallevel;
	
	static final String		desc = "Constant rate of production";
	static final String	[]	paramDescriptions = {"H_Nodex","Final"};
	static final String	[]	nodeDescriptions = {"Target node"};
	static final int	[]	whichSides = { -1, -1 };
	
	public ConstantLevelAff()	{}

	protected void setLabelsAndTypes()	{
		setDescriptions(this.desc, null, paramDescriptions);
		setSided(true, whichSides);

		this.Type[GUI_CAPABLE] = 1;
		this.Type[CERTIFICATION] = Affector.RETURNS_DERIV;
		this.Type[MATHTYPE] = Affector.CC;
		this.Type[TERMTYPE] = Affector.PRODUCTION;
	}
	
	
	public void setParameterNumbers(int [] param_nums)
	{
		halflifeparam = param_nums[0];
		finallevel = param_nums[1];
	}
		
	public float getValue(Node which_node)	{
		return Globals.characteristicTime*params[finallevel]/params[halflifeparam];
	}
}