bundles/org.eclipse.e4.languages.javascript.debug/src/org/eclipse/e4/languages/javascript/rhino/jsdi/StackFrameImpl.java

package org.eclipse.e4.languages.javascript.rhino.jsdi;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.e4.languages.javascript.debug.JSONConstants;
import org.eclipse.e4.languages.javascript.debug.connect.DisconnectException;
import org.eclipse.e4.languages.javascript.debug.connect.Request;
import org.eclipse.e4.languages.javascript.debug.connect.Response;
import org.eclipse.e4.languages.javascript.debug.connect.TimeoutException;
import org.eclipse.e4.languages.javascript.jsdi.Location;
import org.eclipse.e4.languages.javascript.jsdi.StackFrame;
import org.eclipse.e4.languages.javascript.jsdi.Value;
import org.eclipse.e4.languages.javascript.jsdi.Variable;

/**
 * Rhino implementation of {@link StackFrame}
 * 
 * @since 1.0
 */
public class StackFrameImpl extends MirrorImpl implements StackFrame {

	private final Number frameId;
	private final Number threadId;
	private final Number contextId;
	private final Number ref;
	private final Location location;
	private List variables;
	private VariableImpl thisVariable;

	/**
	 * Constructor
	 * 
	 * @param vm
	 * @param jsonFrame
	 */
	public StackFrameImpl(VirtualMachineImpl vm, Map jsonFrame) {
		super(vm);
		this.threadId = (Number) jsonFrame.get(JSONConstants.THREAD_ID);
		this.frameId = (Number) jsonFrame.get(JSONConstants.FRAME_ID);
		this.contextId = (Number) jsonFrame.get(JSONConstants.CONTEXT_ID);
		this.ref = (Number) jsonFrame.get(JSONConstants.REF);

		Long scriptId = new Long(((Number) jsonFrame.get(JSONConstants.SCRIPT_ID)).longValue());
		ScriptReferenceImpl script = vm.script(scriptId);

		String function = (String) jsonFrame.get(JSONConstants.FUNCTION);
		if (function != null) {
			this.location = script.functionLocation(function);
		} else {
			Number line = (Number) jsonFrame.get(JSONConstants.LINE);
			this.location = script.lineLocation(line.intValue());
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.languages.javascript.jsdi.StackFrame#evaluate(java.lang.String)
	 */
	public Value evaluate(String expression) {
		Request request = new Request(JSONConstants.EVALUATE);
		request.getArguments().put(JSONConstants.THREAD_ID, threadId);
		request.getArguments().put(JSONConstants.FRAME_ID, frameId);
		request.getArguments().put(JSONConstants.EXPRESSION, expression);
		try {
			Response response = vm.sendRequest(request, 30000);
			return createValue(response.getBody());
		} catch (DisconnectException e) {
			e.printStackTrace();
		} catch (TimeoutException e) {
			e.printStackTrace();
		}
		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.languages.javascript.jsdi.StackFrame#getValue(org.eclipse.e4.languages.javascript.jsdi.Variable)
	 */
	public Value getValue(Variable variable) {
		VariableImpl variableImpl = (VariableImpl) variable;
		return lookupValue(variableImpl.getRef());
	}

	/**
	 * @param ref
	 * @return
	 */
	public Value lookupValue(Number ref) {
		Request request = new Request(JSONConstants.LOOKUP);
		request.getArguments().put(JSONConstants.THREAD_ID, threadId);
		request.getArguments().put(JSONConstants.FRAME_ID, frameId);
		request.getArguments().put(JSONConstants.HANDLE, ref);
		try {
			Response response = vm.sendRequest(request, 30000);
			return createValue(response.getBody());
		} catch (DisconnectException e) {
			e.printStackTrace();
		} catch (TimeoutException e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * Creates a new type value for the given type description in the map
	 * 
	 * @param body
	 * @return the new type
	 * @throws IllegalStateException
	 *             if the type description in the map is unknown
	 */
	private Value createValue(Map body) throws IllegalStateException {
		Map lookup = (Map) body.get(JSONConstants.LOOKUP);
		String type = (String) lookup.get(JSONConstants.TYPE);
		// "undefined", "null", "boolean", "number", "string", "object", "function"

		if (type.equals(JSONConstants.UNDEFINED))
			return vm.undefinedValue;
		else if (type.equals(JSONConstants.NULL))
			return vm.nullValue;
		else if (type.equals(JSONConstants.BOOLEAN))
			return new BooleanValueImpl(vm, lookup);
		else if (type.equals(JSONConstants.NUMBER))
			return new NumberValueImpl(vm, lookup);
		else if (type.equals(JSONConstants.STRING))
			return new StringValueImpl(vm, lookup);
		else if (type.equals(JSONConstants.OBJECT))
			return new ObjectReferenceImpl(vm, lookup, this);
		else if (type.equals(JSONConstants.FUNCTION))
			return new FunctionReferenceImpl(vm, lookup, this);
		else if (type.equals(JSONConstants.ARRAY))
			return new ArrayReferenceImpl(vm, lookup, this);
		else
			throw new IllegalStateException();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.languages.javascript.jsdi.StackFrame#location()
	 */
	public Location location() {
		return location;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.languages.javascript.jsdi.StackFrame#thisObject()
	 */
	public synchronized Variable thisObject() {
		initializeVariables();
		return thisVariable;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.e4.languages.javascript.jsdi.StackFrame#variables()
	 */
	public synchronized List variables() {
		initializeVariables();
		return variables;
	}

	/**
	 * Initializes and caches the live set of variables
	 */
	private void initializeVariables() {
		if (variables != null) {
			return;
		}
		Request request = new Request(JSONConstants.LOOKUP);
		request.getArguments().put(JSONConstants.THREAD_ID, threadId);
		request.getArguments().put(JSONConstants.FRAME_ID, frameId);
		request.getArguments().put(JSONConstants.HANDLE, ref);
		try {
			Response response = vm.sendRequest(request, 30000);
			Map lookup = (Map) response.getBody().get(JSONConstants.LOOKUP);
			List properties = (List) lookup.get(JSONConstants.PROPERTIES);
			variables = new ArrayList();
			for (Iterator iterator = properties.iterator(); iterator.hasNext();) {
				Map property = (Map) iterator.next();
				String name = (String) property.get(JSONConstants.NAME);
				Number ref = (Number) property.get(JSONConstants.REF);
				VariableImpl variable = new VariableImpl(vm, name, ref);
				if (name.equals(JSONConstants.THIS))
					thisVariable = variable;
				else
					variables.add(variable);
			}
		} catch (DisconnectException e) {
			e.printStackTrace();
		} catch (TimeoutException e) {
			e.printStackTrace();
		}
	}

	/**
	 * Returns if this stack frame is visible
	 * 
	 * @param variable
	 * @return true if this frame is visible, false otherwise
	 */
	public synchronized boolean isVisible(VariableImpl variable) {
		return variables != null && (thisVariable == variable || variables.contains(variable));
	}

	/**
	 * @return the context id for this frame
	 */
	public Number getContextId() {
		return contextId;
	}
}