// Copyright (c) 2009 The Chromium Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

package org.chromium.debug.core.model;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Collections;

import java.util.Comparator;

import java.util.List;

import java.util.Set;

import org.chromium.debug.core.ChromiumDebugPlugin;

import org.chromium.sdk.CallFrame;

import org.chromium.sdk.DebugContext;

import org.chromium.sdk.JsArray;

import org.chromium.sdk.JsFunction;

import org.chromium.sdk.JsObject;

import org.chromium.sdk.JsScope;

import org.chromium.sdk.JsValue;

import org.chromium.sdk.JsVariable;

import org.chromium.sdk.Script;

import org.chromium.sdk.internal.tools.v8.MethodIsBlockingException;

import org.eclipse.core.runtime.IStatus;

import org.eclipse.core.runtime.Status;

import org.eclipse.debug.core.DebugException;

import org.eclipse.debug.core.model.IRegisterGroup;

import org.eclipse.debug.core.model.IStackFrame;

import org.eclipse.debug.core.model.IThread;

import org.eclipse.debug.core.model.IVariable;

/**

 * An IStackFrame implementation over a JsStackFrame instance.

 */

public class StackFrame extends DebugElementImpl implements IStackFrame {

  private final JavascriptThread thread;

  private final CallFrame stackFrame;

  private IVariable[] variables;

  /**

   * Constructs a stack frame for the given handler using the FrameMirror data

   * from the remote V8 VM.

   *

   * @param debugTarget the global parent

   * @param thread for which the stack frame is created

   * @param stackFrame an underlying SDK stack frame

   */

  public StackFrame(DebugTargetImpl debugTarget, JavascriptThread thread, CallFrame stackFrame) {

    super(debugTarget);

    this.thread = thread;

    this.stackFrame = stackFrame;

  }

  public CallFrame getCallFrame() {

    return stackFrame;

  }

  public IThread getThread() {

    return thread;

  }

  public IVariable[] getVariables() throws DebugException {

    if (variables == null) {

      try {

        variables = wrapScopes(getDebugTarget(), stackFrame.getVariableScopes(),

            stackFrame.getReceiverVariable());

      } catch (RuntimeException e) {

        // We shouldn't throw RuntimeException from here, because calling

        // ElementContentProvider#update will forget to call update.done().

        throw new DebugException(new Status(IStatus.ERROR, ChromiumDebugPlugin.PLUGIN_ID,

            "Failed to read variables", e)); //$NON-NLS-1$

      }

    }

    return variables;

  }

  static IVariable[] wrapVariables(

      DebugTargetImpl debugTarget, Collection<? extends JsVariable> jsVars,

      Set<? extends String> propertyNameBlackList,

      Collection <? extends JsVariable> jsInternalProperties) {

    List<Variable> vars = new ArrayList<Variable>(jsVars.size());

    for (JsVariable jsVar : jsVars) {

      if (propertyNameBlackList.contains(jsVar.getName())) {

        continue;

      }

      vars.add(new Variable(debugTarget, jsVar, false));

    }

    // Sort all regular properties by name.

    Collections.sort(vars, VARIABLE_COMPARATOR);

    // Always put internal properties in the end.

    if (jsInternalProperties != null) {

      for (JsVariable jsMetaVar : jsInternalProperties) {

        vars.add(new Variable(debugTarget, jsMetaVar, true));

      }

    }

    return vars.toArray(new IVariable[vars.size()]);

  }

  static IVariable[] wrapScopes(DebugTargetImpl debugTarget, List<? extends JsScope> jsScopes,

      JsVariable receiverVariable) {

    List<Variable> vars = new ArrayList<Variable>();

    for (JsScope scope : jsScopes) {

      if (scope.getType() == JsScope.Type.GLOBAL) {

        if (receiverVariable != null) {

          vars.add(new Variable(debugTarget, receiverVariable, false));

          receiverVariable = null;

        }

        vars.add(new Variable(debugTarget, wrapScopeAsVariable(scope), false));

      } else {

        int startPos = vars.size();

        for (JsVariable var : scope.getVariables()) {

          vars.add(new Variable(debugTarget, var, false));

        }

        int endPos = vars.size();

        List<Variable> sublist = vars.subList(startPos, endPos);

        Collections.sort(sublist, VARIABLE_COMPARATOR);

      }

    }

    if (receiverVariable != null) {

      vars.add(new Variable(debugTarget, receiverVariable, false));

    }

    IVariable[] result = new IVariable[vars.size()];

    // Return in reverse order.

    for (int i = 0; i < result.length; i++) {

      result[result.length - i - 1] = vars.get(i);

    }

    return result;

  }

  private static JsVariable wrapScopeAsVariable(final JsScope jsScope) {

    class ScopeObjectVariable implements JsVariable, JsObject {

      public String getFullyQualifiedName() {

        return getName();

      }

      public String getName() {

        // TODO(peter.rybin): should we localize it?

        return "<" + jsScope.getType() + ">";

      }

      public JsValue getValue() throws UnsupportedOperationException {

        return this;

      }

      public boolean isMutable() {

        return false;

      }

      public boolean isReadable() {

        return true;

      }

      public void setValue(String newValue, SetValueCallback callback)

          throws UnsupportedOperationException {

        throw new UnsupportedOperationException();

      }

      public JsArray asArray() {

        return null;

      }

      public JsFunction asFunction() {

        return null;

      }

      public String getClassName() {

        // TODO(peter.rybin): should we localize it?

        return "#Scope";

      }

      public Collection<? extends JsVariable> getProperties() throws MethodIsBlockingException {

        return jsScope.getVariables();

      }

      public Collection<? extends JsVariable> getInternalProperties()

          throws MethodIsBlockingException {

        return Collections.emptyList();

      }

      public JsVariable getProperty(String name) {

        for (JsVariable var : getProperties()) {

          if (var.getName().equals(name)) {

            return var;

          }

        }

        return null;

      }

      public JsObject asObject() {

        return this;

      }

      public Type getType() {

        return Type.TYPE_OBJECT;

      }

      public String getValueString() {

        return getClassName();

      }

      public String getRefId() {

        return null;

      }

    }

    return new ScopeObjectVariable();

  }

  public boolean hasVariables() throws DebugException {

    return stackFrame.getReceiverVariable() != null || stackFrame.getVariableScopes().size() > 0;

  }

  public int getLineNumber() throws DebugException {

  }

  public int getCharStart() throws DebugException {

    return stackFrame.getCharStart();

  }

  public int getCharEnd() throws DebugException {

    return -1;

  }

  public String getName() throws DebugException {

    return getDebugTarget().getLabelProvider().getStackFrameLabel(this);

  }

  public IRegisterGroup[] getRegisterGroups() throws DebugException {

    return null;

  }

  public boolean hasRegisterGroups() throws DebugException {

    return false;

  }

  public boolean canStepInto() {

    return getThread().canStepInto();

  }

  public boolean canStepOver() {

    return getThread().canStepOver();

  }

  public boolean canStepReturn() {

    return getThread().canStepReturn();

  }

  public boolean isStepping() {

    return getThread().isStepping();

  }

  public void stepInto() throws DebugException {

    getThread().stepInto();

  }

  public void stepOver() throws DebugException {

    getThread().stepOver();

  }

  public void stepReturn() throws DebugException {

    getThread().stepReturn();

  }

  public boolean canResume() {

    return getThread().canResume();

  }

  public boolean canSuspend() {

    return getThread().canSuspend();

  }

  public boolean isSuspended() {

    return getThread().isSuspended();

  }

  public void resume() throws DebugException {

    getThread().resume();

  }

  public void suspend() throws DebugException {

    getThread().suspend();

  }

  public boolean canTerminate() {

    return getThread().canTerminate();

  }

  public boolean isTerminated() {

    return getThread().isTerminated();

  }

  public void terminate() throws DebugException {

    getThread().terminate();

  }

  /**

   * Returns the name of the source file this stack frame is associated with.

   *

   * @return the name of the source file this stack frame is associated with

   */

  String getSourceName() {

    Script script = stackFrame.getScript();

    if (script == null) {

      return Messages.StackFrame_UnknownScriptName;

    }

    return script.getName();

  }

  @Override

  public boolean equals(Object obj) {

    if (obj instanceof StackFrame) {

      StackFrame other = (StackFrame) obj;

      return other.stackFrame.equals(this.stackFrame);

    }

    return false;

  }

  @Override

  public int hashCode() {

    return stackFrame.hashCode();

  }

  private final static Comparator<Variable> VARIABLE_COMPARATOR = new Comparator<Variable>() {

    public int compare(Variable var1, Variable var2) {

      return compareNameObjects(getNameObject(var1), getNameObject(var2));

    }

    // Get property name as String or Integer.

    private Object getNameObject(Variable var) {

      String name = var.getName();

      int len = name.length();

      if (len >= 3 && name.charAt(0) == '[' && name.charAt(len-1) == ']') {

        Integer i = Integer.valueOf(name.substring(1, len - 1));

        return i;

      }

      return name;

    }

    // Compare property name (either string or integer).

    private int compareNameObjects(Object nameObj1, Object nameObj2) {

      if (nameObj1 instanceof Integer) {

        Integer i1 = (Integer) nameObj1;

        if (nameObj2 instanceof Integer) {

          Integer i2 = (Integer) nameObj2;

          return i1.compareTo(i2);

        } else {

          return COMPARE_INT_WITH_STRING;

        }

      } else {

        String s1 = (String) nameObj1;

        if (nameObj2 instanceof String) {

          String s2 = (String) nameObj2;

          return s1.compareTo(s2);

        } else {

          return -COMPARE_INT_WITH_STRING;

        }

      }

    }

    // Strings go before numbers.

    private static final int COMPARE_INT_WITH_STRING = 1;

  };

  @Override

  @SuppressWarnings("unchecked")

  public Object getAdapter(Class adapter) {

    if (adapter == EvaluateContext.class) {

      DebugContext debugContext = getDebugTarget().getDebugContext();

      if (debugContext == null) {

        return null;

      }

      return new EvaluateContext(getCallFrame().getEvaluateContext(), getDebugTarget());

    }

    return super.getAdapter(adapter);

  }

}