package org.jzy3d.plot3d.pipelines;
import org.apache.log4j.Logger;

import com.jogamp.opengl.GL;
import com.jogamp.opengl.GL2ES1;
import com.jogamp.opengl.GL2ES2;

/** This utility allows checking the GL2 error bit after a call to a 
 * GL2 command.
 * 
 * When an error is detected, a textual information is printed out in console.
 * @author Martin Pernollet
 */
public class GLErrorReader {
	static Logger logger = Logger.getLogger(GLErrorReader.class);
	
	/** If an error occured, print it and add an information string 
	 * at the following line.*/
	public static void getAndPrintError(GL gl, String info){
		if(getAndPrintError(gl))
			logger.error(info);
	}
	
	/** If an error occured, print it.*/
	public static boolean getAndPrintError(GL gl){
    	int err = gl.glGetError(); 
    	
    	boolean status = true; // assume an error
    	
        if(err==GL.GL_NO_ERROR){
            //No error has been recorded. The value of this symbolic constant is guaranteed to be zero.
        	status = false;
        }
        else if(err==GL.GL_INVALID_ENUM){
        	logger.error("GL_INVALID_ENUM: An unacceptable value is specified for an enumerated argument. The offending command is ignored, having no side effect other than to set the error flag.");
        }
        else if(err==GL.GL_INVALID_VALUE){
        	logger.error("GL_INVALID_VALUE: A numeric argument is out of range. The offending command is ignored, having no side effect other than to set the error flag.");
        }
        else if(err==GL.GL_INVALID_OPERATION){
	        logger.error("GL_INVALID_OPERATION : The specified operation is not allowed in the current state. The offending command is ignored, having no side effect other than to set the error flag.");
        }
        else if(err==GL2ES1.GL_STACK_OVERFLOW || err==GL2ES2.GL_STACK_OVERFLOW){
        	logger.error("GL_STACK_OVERFLOW: This command would cause a stack overflow. The offending command is ignored, having no side effect other than to set the error flag.");
        }
        else if(err==GL2ES1.GL_STACK_UNDERFLOW || err==GL2ES2.GL_STACK_UNDERFLOW){
	        logger.error("GL_STACK_UNDERFLOW: This command would cause a stack underflow. The offending command is ignored, having no side effect other than to set the error flag.");
        }
        else if(err==GL.GL_OUT_OF_MEMORY){
        	logger.error("GL_OUT_OF_MEMORY: There is not enough memory left to execute the command. The state of the GL2 is undefined, except for the state of the error flags, after this error is recorded.");
        }
        
        return status;
    }
}