package org.symbian.tools.tmw.previewer.preview;

import java.net.URI;

import java.util.Collection;

import org.eclipse.core.resources.IFile;

import org.eclipse.core.resources.IProject;

import org.eclipse.core.resources.ResourcesPlugin;

import org.eclipse.core.runtime.IPath;

import org.eclipse.jface.action.Action;

import org.eclipse.jface.action.IAction;

import org.eclipse.jface.action.IToolBarManager;

import org.eclipse.jface.viewers.ISelection;

import org.eclipse.jface.viewers.ISelectionChangedListener;

import org.eclipse.jface.viewers.ISelectionProvider;

import org.eclipse.jface.viewers.StructuredSelection;

import org.eclipse.swt.browser.Browser;

import org.eclipse.swt.layout.GridData;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Control;

import org.eclipse.ui.actions.ActionFactory;

import org.eclipse.ui.part.IPageSite;

import org.eclipse.ui.part.Page;

import org.symbian.tools.tmw.core.utilities.CoreUtil;

import org.symbian.tools.tmw.previewer.Images;

import org.symbian.tools.tmw.previewer.PreviewerPlugin;

public abstract class AbstractPreviewPage extends Page implements IPreviewPage, ISelectionProvider {

    private final IAction refreshAction = new Action("Refresh") {

        public void run() {

            refresh(true);

        };

    };

    private final IAction toggleRefresh = new Action("Toggle Refresh", IAction.AS_RADIO_BUTTON) {

        public void run() {

            toggleRefresh();

        };

    };

    private IProject project;

    private Browser browser;

    private boolean toggleState = true;

    private final PreviewView previewView;

    private boolean needsRefresh = false;

    public AbstractPreviewPage(IProject project, PreviewView previewView) {

        this.project = project;

        this.previewView = previewView;

    }

    protected synchronized void toggleRefresh() {

        toggleState = !toggleState;

        toggleRefresh.setChecked(toggleState);

        previewView.setProjectAutorefresh(project, toggleState);

        toggleRefresh.setToolTipText(getToggleActionTooltip());

        if (toggleState && needsRefresh) {

            refresh(true);

        }

    }

    @Override

    public void createControl(Composite parent) {

        browser = createBrowser(parent);

        browser.setLayoutData(new GridData(GridData.FILL_BOTH));

        browser.setUrl(getURI().toASCIIString());

    }

    protected abstract Browser createBrowser(Composite parent);

    private URI getURI() {

        return PreviewerPlugin.getDefault().getHttpPreviewer().previewProject(project, null);

    }

    @Override

    public Control getControl() {

        return browser;

    }

    @Override

    public void setFocus() {

        if (browser != null && !browser.isDisposed()) {

            browser.setFocus();

        }

    }

    private boolean refreshScheduled = false;

    public synchronized void process(Collection<IFile> files) {

        if (!isDisposed() && !refreshScheduled && needsRefresh(files)) {

            asyncExec(new Runnable() {

                public void run() {

                    refreshBrowser();

                }

            });

            refreshScheduled = true;

        }

    }

    protected void promptIfNeeded() {

        if (toggleState) {

            toggleState = previewView.promptUserToToggle(project, toggleState);

            toggleRefresh.setChecked(toggleState);

        }

    }

    private void asyncExec(Runnable runnable) {

        getControl().getDisplay().asyncExec(runnable);

    }

    private boolean needsRefresh(Collection<IFile> files) {

        for (IFile iFile : files) {

            if (iFile.getProject().equals(project)) {

                return true;

            }

        }

        return false;

    }

    protected synchronized void refresh(final boolean manual) {

        try {

            if (!isDisposed()) {

                final Control focusControl = browser.getDisplay().getFocusControl();

                if (manual && CoreUtil.isMac()) {

                    browser.getParent().forceFocus();

                }

                browser.setUrl(getURI().toASCIIString());

                refreshAction.setImageDescriptor(PreviewerPlugin.getImageDescriptor(Images.GREEN_SYNC));

                asyncExec(new Runnable() {

                    public void run() {

                        if (!manual && focusControl != null && !focusControl.isDisposed()) {

                            focusControl.setFocus();

                        } else if (manual) {

                            browser.forceFocus();

                        }

                    }

                });

                refreshAction.setToolTipText("Refresh the preview browser");

            }

            needsRefresh = false;

        } finally {

            refreshScheduled = false;

        }

    }

    @Override

    public void init(IPageSite pageSite) {

        super.init(pageSite);

        IToolBarManager toolBar = pageSite.getActionBars().getToolBarManager();

        contributeToToolbar(toolBar);

        refreshAction.setImageDescriptor(PreviewerPlugin.getImageDescriptor(Images.GREEN_SYNC));

        refreshAction.setToolTipText("Refresh the preview browser");

        toolBar.add(refreshAction);

        toggleState = previewView.getProjectAutorefresh(project);

        toggleRefresh.setImageDescriptor(PreviewerPlugin.getImageDescriptor(Images.YELLOW_SYNC));

        toggleRefresh.setToolTipText(getToggleActionTooltip());

        toggleRefresh.setChecked(toggleState);

        toolBar.add(toggleRefresh);

        pageSite.getActionBars().setGlobalActionHandler(ActionFactory.REFRESH.getId(), refreshAction);

        getSite().setSelectionProvider(this);

    }

    protected void contributeToToolbar(IToolBarManager toolBar) {

        // Do nothing here

    }

    private String getToggleActionTooltip() {

        if (toggleState) {

            return "Disable preview autorefresh";

        } else {

            return "Enable preview autorefresh";

        }

    }

    public void addSelectionChangedListener(ISelectionChangedListener listener) {

        // Do nothing

    }

    public ISelection getSelection() {

        return new StructuredSelection(project);

    }

    public void removeSelectionChangedListener(ISelectionChangedListener listener) {

        // Do nothing

    }

    public void setSelection(ISelection selection) {

        // Do nothing

    }

    public boolean isDisposed() {

        return browser != null && browser.isDisposed();

    }

    private synchronized void refreshBrowser() {

        if (toggleState) {

            promptIfNeeded();

        }

        if (toggleState) {

            refresh(false);

        } else {

            needsRefresh = true;

            refreshAction.setImageDescriptor(PreviewerPlugin.getImageDescriptor(Images.RED_SYNC));

            refreshAction.setToolTipText("Refresh the preview browser (there are updated files)");

        }

    }

    public IProject getProject() {

        return project;

    }

    public synchronized void projectRenamed(IPath newPath) {

        if (!isDisposed()) {

            project = ResourcesPlugin.getWorkspace().getRoot().getProject(newPath.lastSegment());

        }

    }

}