--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/camerauis/cameraxui/cxengine/src/cxestatemachinebase.cpp	Tue Aug 31 15:03:46 2010 +0300
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2009-2010 Nokia Corporation and/or its subsidiary(-ies).
+ * All rights reserved.
+ * This component and the accompanying materials are made available
+ * under the terms of "Eclipse Public License v1.0"
+ * which accompanies this distribution, and is available
+ * at the URL "http://www.eclipse.org/legal/epl-v10.html".
+ *
+ * Initial Contributors:
+ * Nokia Corporation - initial contribution.
+ *
+ * Contributors:
+ *
+ * Description:
+ *
+ */
+
+#include "cxestatemachinebase.h"
+#include "cxutils.h"
+#include "cxestate.h"
+
+CxeStateMachineBase::CxeStateMachineBase(const char *stateMachineName) :
+    mStateBitsUsed(0), mStateId(0), mName(stateMachineName)
+{
+}
+
+CxeStateMachineBase::~CxeStateMachineBase()
+{
+    qDeleteAll(mStates);
+    mStates.clear();
+}
+
+bool CxeStateMachineBase::addState(CxeState *state)
+{
+    bool success( state // non-null state object
+               && state->stateId() // state id is not zero
+               && !(mStateBitsUsed & state->stateId()) // no overlapping bits
+                );
+
+    // if no errors
+    if (success) {
+        mStateBitsUsed |= state->stateId();
+        mStates[state->stateId()] = state; // state is now owned by the state machine
+    }
+
+    return success;
+}
+
+bool CxeStateMachineBase::setState(int stateId, CxeError::Id error)
+{
+    bool success = true;
+
+    if (stateId == mStateId) {
+        // No transition, nothing needs to be done
+        return success;
+    }
+
+    if (mStates.contains(stateId)) {
+        // New state name known, print it
+        CX_DEBUG(("%s::setState(%s, %d)", mName.toAscii().constData(),
+                mStates[stateId]->name().toAscii().constData(), error));
+    } else {
+        // Unknown state...
+        CX_DEBUG(("%s::setState(UNKNOWN[%d], %d)", mName.toAscii().constData(),
+                stateId, error));
+    }
+
+    // State state machine does not use the error parameter itself.
+    // It is only forwarded to handleStateChanged to be passed
+    // on as a parameter in the stateChanged() signal.
+
+    // setStateId itself will never return an error.
+    // If an illegal state or state change is detected, it will panic the application (because it is a design error).
+
+    success = verifyStateChange(stateId);
+
+    if (success) {
+        mStateId = stateId;
+        handleStateChanged(mStateId, error);
+    }
+
+    return success;
+}
+
+bool CxeStateMachineBase::setInitialState(int stateId)
+{
+    bool success = mStates.contains(stateId);
+
+    if (success) {
+        // New state name known, print it
+        CX_DEBUG(("%s::setInitialState(%s)", mName.toAscii().constData(),
+                mStates[stateId]->name().toAscii().constData()));
+    } else {
+        // Unknown state...
+        CX_DEBUG(("%s::setInitialState(UNKNOWN[%d])", mName.toAscii().constData(),
+                stateId));
+    }
+
+    // check that state changes have not been made
+    // and this is the one and only setInitialState call
+    success = (success && mStateId == 0);
+
+    if (success) {
+        mStateId = stateId;
+    } else {
+        CX_DEBUG(("%s state has already been set", mName.toAscii().constData()));
+    }
+    return success;
+}
+
+int CxeStateMachineBase::stateId() const
+{
+    return mStateId;
+}
+
+bool CxeStateMachineBase::verifyStateChange(int newStateId)
+{
+    bool allowStateChange = false;
+
+    // Check that current state can be found in the state chart
+    if ( mStates.contains(stateId()) ) {
+        // Check that current state allows change to the new state
+        CxeState *currentState = mStates[stateId()];
+        allowStateChange = (currentState->allowedNextStates() & newStateId);
+    }
+
+    return allowStateChange;
+}