SnippetOperator.java

package damp.ekeko.snippets.data;

import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeItem;

import clojure.lang.IFn;
import clojure.lang.Keyword;
import clojure.lang.RT;

public class SnippetOperator {

	
	public static IFn FN_OPERATOR_CATEGORIES;
	public static IFn FN_OPERATORCATEGORY_DESCRIPTION;
	public static IFn FN_OPERATOR_NAME;
	public static IFn FN_OPERATOR_ARGUMENT_WITH_PRECONDITION;
	public static IFn FN_OPERATOR_DESCRIPTION;
	public static IFn FN_OPERATOR_ISTRANSFORM;
	public static IFn FN_APPLICABLE_OPERATORS_FOR_TRANSFORMATION;
	public static IFn FN_POSSIBLE_NODES_FOR_OPERATOR_ARGUMENT_IN_GROUP;
	
	public static IFn FN_IS_OPERATOR;
	public static IFn FN_OPERATOR_BINDINGS_FOR_OPERANDS;
	public static IFn FN_OPERATOR_FROM_ID;

	
	public static boolean isOperator(Object value) {
		return (Boolean) FN_IS_OPERATOR.invoke(value);
	}
	
	public static Object[] getArray(Object clojureList) {
		return (Object[]) RT.var("clojure.core", "to-array").invoke(clojureList);
	}
	
	public static Object operatorFromId(String id) {
		return FN_OPERATOR_FROM_ID.invoke(id);
	}
	
	public static void setInputForTransformation(Tree tree, Object selectedNode) {
		tree.removeAll();

		TreeItem root = new TreeItem(tree, 0);
		root.setText("Action");
		root.setData("");
		
		Object[] operators = getArray(FN_APPLICABLE_OPERATORS_FOR_TRANSFORMATION.invoke(selectedNode));
		for (int j = 0; j < operators.length; j++) {
			TreeItem itemOp = new TreeItem(root, 0);
			itemOp.setText((String) FN_OPERATOR_NAME.invoke(operators[j]));
			itemOp.setData(operators[j]);
		}			
		root.setExpanded(true);
	}
	
	public static Object[] getOperands(Object group, Object snippet, Object subjectNode, Object operator) {
		return getArray(FN_OPERATOR_BINDINGS_FOR_OPERANDS.invoke(group, snippet, subjectNode, operator));
	}

	public static String getArgumentWithPrecondition(Object operator) {
		if(operator instanceof Keyword)
			return "";
		
		return (String) FN_OPERATOR_ARGUMENT_WITH_PRECONDITION.invoke(operator);		
	}

	public static Object[] possibleNodesForArgument(Object snippetgroup, Object operator) {
		if(operator instanceof Keyword)
			return new String[0];

		return getArray(FN_POSSIBLE_NODES_FOR_OPERATOR_ARGUMENT_IN_GROUP.invoke(snippetgroup, operator));		
	}

	public static String getDescription(Object operator) {
		String result = (String) FN_OPERATOR_DESCRIPTION.invoke(operator);
		if (result == null)
			return "";
		return result;		
	}

	public static boolean isTransformOperator(Object operator) {
		return (Boolean) FN_OPERATOR_ISTRANSFORM.invoke(operator);
	}

}