/*
 * The MIT License
 *
 * Copyright (c) 2011, CloudBees, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package hudson.model;

import java.util.Locale;
import org.kohsuke.stapler.export.Exported;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import edu.umd.cs.findbugs.annotations.CheckForNull;
import edu.umd.cs.findbugs.annotations.NonNull;

/**
 * Implements {@link ViewGroup} to be used as a "mix-in".
 * Not meant for a consumption from outside {@link ViewGroup}s.
 *
 * <h2>How to use this class</h2>
 * <ol>
 * <li>
 * Create three data fields in your class:
 * <pre>{@code
 * private String primaryView;
 * private CopyOnWriteArrayList<View> views;
 * private ViewsTabBar viewsTabBar;
 * }</pre>
 * <li>
 * Define a transient field and store ViewGroupMixIn subtype, then wire up getters and setters:
 * <pre>
 * private transient ViewGroupMixIn = new ViewGroupMixIn() {
 *     List&lt;View&gt; views() { return views; }
 *     ...
 * }
 * </pre>
 * </ol>
 * @author Kohsuke Kawaguchi
 * @see ItemGroupMixIn
 */
public abstract class ViewGroupMixIn {
    private final ViewGroup owner;

    /**
     * Returns all views in the group. This list must be modifiable and concurrently iterable.
     */
    @NonNull
    protected abstract List<View> views();

    /**
     * Gets primary view of the mix-in.
     * @return Name of the primary view, {@code null} if there is no primary one defined.
     */
    @CheckForNull
    protected abstract String primaryView();

    /**
     * Sets the primary view.
     * @param newName Name of the primary view to be set.
     *                {@code null} to make the primary view undefined.
     */
    protected abstract void primaryView(String newName);

    protected ViewGroupMixIn(ViewGroup owner) {
        this.owner = owner;
    }

    public void addView(@NonNull View v) throws IOException {
        v.owner = owner;
        views().add(v);
        owner.save();
    }

    public boolean canDelete(@NonNull View view) {
        return !view.isDefault();  // Cannot delete primary view
    }

    public synchronized void deleteView(@NonNull View view) throws IOException {
        if (views().size() <= 1)
            throw new IllegalStateException("Cannot delete last view");
        views().remove(view);
        owner.save();
    }

    /**
     * Gets a view by the specified name.
     * The method iterates through {@link ViewGroup}s if required.
     * @param name Name of the view
     * @return View instance or {@code null} if it is missing
     */
    @CheckForNull
    public View getView(@CheckForNull String name) {
        if (name == null) {
            return null;
        }
        //Top level views returned first if match
        List<View> views = views();
        for (View v : views) {
            if (v.getViewName().equals(name)) {
                return v;
            }
        }
        for (View v : views) {
            //getAllViews() cannot be used as it filters jobs by permission which is bad e.g. when trying to add a new job
            if (v instanceof ViewGroup) {
                View nestedView = ((ViewGroup) v).getView(name);
                if (nestedView != null) {
                    return nestedView;
                }
            }
        }
        if (!name.equals(primaryView())) {
            // Fallback to subview of primary view if it is a ViewGroup
            View pv = getPrimaryView();
            if (pv instanceof ViewGroup)
                return ((ViewGroup)pv).getView(name);
            if (pv instanceof AllView && AllView.DEFAULT_VIEW_NAME.equals(pv.name)) {
                // JENKINS-38606: primary view is the default AllView, is somebody using an old link to localized form?
                for (Locale l : Locale.getAvailableLocales()) {
                    if (name.equals(Messages._Hudson_ViewName().toString(l))) {
                        // why yes they are, let's keep that link working
                        return pv;
                    }
                }
            }
        }
        return null;
    }

    /**
     * Gets the read-only list of all {@link View}s.
     */
    @Exported
    public Collection<View> getViews() {
        List<View> orig = views();
        List<View> copy = new ArrayList<>(orig.size());
        for (View v : orig) {
            if (v.hasPermission(View.READ))
                copy.add(v);
        }
        copy.sort(View.SORTER);
        return copy;
    }

    /**
     * Returns the primary {@link View} that renders the top-page of Hudson or
     * {@code null} if there is no primary one defined.
     */
    @Exported
    @CheckForNull
    public View getPrimaryView() {
        View v = getView(primaryView());
        if(v==null && !views().isEmpty()) // fallback
            v = views().get(0);
        return v;
    }

    public void onViewRenamed(View view, String oldName, String newName) {
        // If this view was the default view, change reference
        if (oldName.equals(primaryView())) {
            primaryView(newName);
        }
    }
}
