function chequea_primero(numero) {
	if (document.getElementById(numero).checked){
		if (cadena!="")	{
			cadena += " | "+numero;
		} else{
			cadena += numero;
		}
		item_previo = true;
	}
}

function chequea_medio(numero) {
	if (document.getElementById(numero).checked){
		if (cadena!="")	{
			if (item_previo){
				cadena += " "+numero;
			} else{
				cadena += " | "+numero;
			}
		} else{
			cadena += numero;
		}
		item_previo = true;
	}
}

function chequea_separa(numero) {
	if (document.getElementById(numero).checked){
		if (cadena!="")	{
			if (item_previo){
				if (separador_previo){
					cadena += " , "+numero; separador_previo = false;
				} else{
					cadena += " "+numero;
				}
			} else{
				cadena += " | "+numero;
			}
		} else{
			cadena += numero;
		}
		item_previo = true;
	}
}

function crea() {
	cadena_inicial = "<html>";
	cadena_inicial += "\n" + "<head>";
	cadena_inicial += "\n";
	cadena_inicial += "\n" + "</head>";
	cadena_inicial += "\n";
	cadena_inicial += "\n" + "<body>";
	cadena_inicial += "\n" + "<p align='center'>";
	cadena_inicial += "\n";
	cadena_inicial += "\n" + "<applet ";
	cadena_inicial += "\n\t" + "codeBase='./'";
	cadena_inicial += "\n\t" + "code='geogebra.GeoGebraApplet'";
	cadena_inicial += "\n\t" + "archive='" + document.getElementById("jar").value + "geogebra.jar'";
	cadena_inicial += "\n\t" + "width='" + document.getElementById("ancho").value +"'";
	cadena_inicial +=  "\t" + " height='" + document.getElementById("alto").value + "' name=Animacion>";
	cadena_inicial +=  "\n\t" + "<param name='filename' value='" + document.getElementById("ggb").value + "'>";
	if (document.getElementById("boton_no").checked){
		if (document.getElementById("menu_si").checked){
			cadena_inicial += "\n\t" + "<param name='showMenuBar' value='true'>" + "\n";
		}
		if (document.getElementById("entrada_si").checked){
			cadena_inicial += "\n\t" + "<param name='showAlgebraInput' value='true'>\n";
		}
		if (document.getElementById("icono_si").checked){
			cadena_inicial += "\n\t" + "<param name='showResetIcon' value='true'>";
		}
		if (document.getElementById("abrir_no").checked){
			cadena_inicial += "\n\t" + "<param name='framePossible' value='false'>";
		}
	}
	cadena_final = "\n\t" + "Lo sentimos, el applet Geogebra no pudo iniciarse.";
	cadena_final += "\n\t" + "<br>Por favor, comprueba que la plataforma Java 1.4.2 (o posterior) está instalada y activada.";
	cadena_final += " <br>(<a href='http://java.sun.com/getjava'>Pulsa aquí para instalar Java ahora</a>)<br><br>";
	cadena_final += "\n" + "</applet>";
	
	document.getElementById("expresion").value = "";
	cadena = "";
	item_previo = false;
	separador_previo = false;

	if (document.getElementById("algunos").checked){

		if (document.getElementById("0").checked){
			cadena += "0"; 
			menu_previo = true; 
		}
		if (document.getElementById("39").checked){
			if (cadena!="")	{
				cadena += " 39";
			} else {
				cadena += "39";
			}
		}

		chequea_primero("1");
		chequea_medio("5");
		chequea_medio("19");
		item_previo = false;

		chequea_primero("2");
		chequea_medio("15");
		chequea_medio("45");
		chequea_medio("18");
		if (document.getElementById("sv1").checked && item_previo){separador_previo = true;}
		chequea_separa("7");
		chequea_separa("37");
		item_previo = false; separador_previo = false;

		chequea_primero("4");
		chequea_medio("3");
		chequea_medio("8");
		chequea_medio("9");
 		if (document.getElementById("sv3").checked && item_previo){separador_previo = true;}
		chequea_separa("13");
		chequea_separa("44");
		if (document.getElementById("sv2").checked  && item_previo){separador_previo = true;}
		chequea_separa("47");
		item_previo = false; separador_previo = false;

		chequea_primero("16");
		chequea_medio("51");

		chequea_primero("10");
		chequea_medio("34");
		chequea_medio("11");
		if (document.getElementById("sv4").checked && item_previo){separador_previo = true;}
		chequea_separa("24");
		chequea_separa("20");
		chequea_separa("22");
		if (document.getElementById("sv5").checked  && item_previo){separador_previo = true;}
		chequea_separa("21");
		chequea_separa("23");
		if (document.getElementById("sv6").checked  && item_previo){separador_previo = true;}
		chequea_separa("12");
		item_previo = false; separador_previo = false;

		chequea_primero("36");
		chequea_medio("46");
		if (document.getElementById("sv7").checked && item_previo){separador_previo = true;}
		chequea_separa("38");
		chequea_separa("49");
		chequea_separa("50");
		item_previo = false; separador_previo = false;

		chequea_primero("29");
		chequea_medio("30");
		chequea_medio("32");
		chequea_medio("31");
		chequea_medio("33");
		item_previo = false; separador_previo = false;

		chequea_primero("25");
		chequea_medio("52");
		if (document.getElementById("sv8").checked  && item_previo){separador_previo = true;}
		chequea_separa("17");
		chequea_separa("26");
		if (document.getElementById("sv11").checked  && item_previo){separador_previo = true;}
		chequea_separa("14");
		item_previo = false; separador_previo = false;

		if (document.getElementById("40").checked){
			if (cadena!="")	{
				if (document.getElementById("sh").checked){
					cadena += " || 40"
				} else{
					cadena += " | 40";
				}
			} else{
				cadena += "40";
			}
			item_previo = true;
		}
		if (document.getElementById("41").checked){
			if (cadena!="")	{
				if (item_previo){
					cadena += " 41";
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 41"
					} else{
						cadena += " | 41";
					}
				}
			} else{
				cadena += "41";
			}
			item_previo = true;
		}
		if (document.getElementById("42").checked){
			if (cadena!="")	{
				if (item_previo){
					cadena += " 42";
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 42"
					} else{
						cadena += " | 42";
					}
				}
			} else{
				cadena += "42";
			}
			item_previo = true;
		}
		if (document.getElementById("sv9").checked && item_previo){separador_previo = true;}
		if (document.getElementById("27").checked){
			if (cadena!="")	{
				if (item_previo){
					if (separador_previo){
						cadena += " , 27"; separador_previo = false;
					} else{
						cadena += " 27";
					}
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 27"
					} else{
						cadena += " | 27";
					}
				}
			} else{
				cadena += "27";
			}
			item_previo = true;
		}
		if (document.getElementById("28").checked){
			if (cadena!="")	{
				if (item_previo){
					if (separador_previo){
						cadena += " , 28"; separador_previo = false;
					} else{
						cadena += " 28";
					}
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 28"
					} else{
						cadena += " | 28";
					}
				}
			} else{
				cadena += "28";
			}
			item_previo = true;
		}
		if (document.getElementById("35").checked){
			if (cadena!="")	{
				if (item_previo){
					if (separador_previo){
						cadena += " , 35"; separador_previo = false;
					} else{
						cadena += " 35";
					}
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 35"
					} else{
						cadena += " | 35";
					}
				}
			} else{
				cadena += "35";
			}
			item_previo = true;
		}
		if (document.getElementById("sv10").checked  && item_previo){separador_previo = true;}
		if (document.getElementById("6").checked){
			if (cadena!="")	{
				if (item_previo){
					if (separador_previo){
						cadena += " , 6"; 
					} else{
						cadena += " 6";
					}
				} else{
					if (document.getElementById("sh").checked){
						cadena += " || 6"
					} else{
						cadena += " | 6";
					}
				}
			} else{
				cadena += "6";
			}
		}
		if (cadena !=""){
			cadena_inicial += "\n\t" + "<param name='showToolBar' value='true'>";
			cadena = "\n\t" + "<param name = 'customToolBar' value='" + cadena + "'>"
		}
	} else {
			if (document.getElementById("boton_si").checked){
				cadena_inicial += "\n\t" +  "<param name='type' value='button'>";
			} else{
				if (document.getElementById("todos").checked){
					cadena_inicial += "\n\t" +  "<param name='showToolBar' value='true'>";
				}
			}
	}

	remate = "";
	ani = document.getElementById("ani1").value;
	inicio = document.getElementById("ini1").value;
	fin = document.getElementById("fin1").value;
	paso = document.getElementById("paso1").value;
	if (eval(fin)==0 || fin==""){
		fin = "1000000";
	}
	
	if (ani!=""){
		remate += "\n" + "<script type='text/javascript'>";
		remate += "\n" + "inicio = " + inicio + ";";	
		remate += "\n" + "fin = " + fin + ";";
		remate += "\n" + "paso = " + paso + ";";
		remate += "\n" + "mueve = false;";
		remate += "\n" + ani + " = " + inicio + ";";
		remate += "\n" + "reloj = null;";
		remate += "\n";
		remate += "\n" + "function reinicio() {";
		remate += "\n\t" + "applet = document.Animacion;";
		remate += "\n\t" + "setTimeout('clearInterval(reloj)', 0);";
		remate += "\n\t" + "mueve = false;";
		remate += "\n\t" + ani + " = inicio;";
		remate += "\n\t" + "applet.evalCommand('" + ani + "=' + " + ani +");";
		remate += "\n" + "}";
		remate += "\n";
		remate += "\n" + "function retrocede() {";
		remate += "\n\t" + "if (!mueve){";
		remate += "\n\t\t" + "mueve = true;";
		remate += "\n\t\t" + "reloj = setInterval('atras()', 50);";
		remate += "\n\t" + "}";
		remate += "\n" + "}";
		remate += "\n";
		remate += "\n" + "function avanza() {";
		remate += "\n\t" + "if (!mueve){";
		remate += "\n\t\t" + "mueve = true;";
		remate += "\n\t\t" + "reloj = setInterval('adelante()', 50);";
		remate += "\n\t" + "}";
		remate += "\n" + "}";
		remate += "\n";
		remate += "\n" + "function pausa() {";
		remate += "\n\t" + "if (mueve){";
		remate += "\n\t\t" + "mueve = false;";
		remate += "\n\t\t" + "setTimeout('clearInterval(reloj)', 0);";
		remate += "\n\t" + "}";
		remate += "\n" + "}";
		remate += "\n";
		remate += "\n" + "function adelante() {";
		remate += "\n\t" + "applet = document.Animacion;";
		remate += "\n\t" + ani + " = applet.getValue('" + ani + "');";
		remate += "\n\t" + "if(" + ani + " < fin) {";
		remate += "\n\t\t" + ani + " = " + ani + " + paso;";		
		remate += "\n\t\t" + "if (" + ani + ">-0.1 && " + ani + "<0){";
		remate += "\n\t\t\t" + ani +"=0;";
		remate += "\n\t\t" + "}";
		remate += "\n\t\t" + "applet.evalCommand('" + ani + "=' + " + ani +");";		
		remate += "\n\t" + "} else{";		
		remate += "\n\t\t" + "setTimeout('clearInterval(reloj)', 0);";		
		remate += "\n\t\t" + "mueve = false;";		
		remate += "\n\t\t" + ani + " = fin;";
		remate += "\n\t\t" + "applet.evalCommand('" + ani + "=' + " + ani +");";		
		remate += "\n\t" + "}";
		remate += "\n" + "}";
		
		remate += "\n" + "function atras() {";
		remate += "\n\t" + "applet = document.Animacion;";
		remate += "\n\t" + ani + " = applet.getValue('" + ani + "');";
		remate += "\n\t" + "if(" + ani +" > inicio) {";
		remate += "\n\t\t" + ani + " = " + ani + " - paso;";		
		remate += "\n\t\t" + "if (" + ani + "<0.1 && " + ani + ">0){";
		remate += "\n\t\t\t" + ani + "=0;";
		remate += "\n\t\t" + "}";
		remate += "\n\t\t" + "applet.evalCommand('" + ani + "=' + " + ani +");";	
		remate += "\n\t" + "} else{";		
		remate += "\n\t\t" + "reinicio();";		
		remate += "\n\t" + "}";
		remate += "\n" + "}";
		remate += "\n" + "</script>";
		remate += "\n" + "<br>"; 
		remate += "\n" + "<INPUT type='image' name='reinicio' src='reinicio.jpg' onclick=reinicio() width='35' height='25'>&nbsp;"; 
		remate += "\n" + "<INPUT type='image' name='pausa' src='pausa.jpg' onclick=pausa() width='35' height='25'>&nbsp;";
		remate += "\n" + "<INPUT type='image' name='retrocede' src='retrocede.jpg' onclick=retrocede() width='35' height='25'>&nbsp;";
		remate += "\n" + "<INPUT type='image' name='avanza' src='avanza.jpg' onclick=avanza() width='35' height='25'>";
		remate += "\n" + "</p>"; 
	}

	remate += "\n";
	remate += "\n" + "</body>";
	remate += "\n" + "</html>";
	document.getElementById("expresion").value = cadena_inicial + cadena + cadena_final + remate;
}