/*******************************************************************************
 *
 * Copyright (c) 2004-2009 Oracle Corporation.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 * 
 *    Kohsuke Kawaguchi, Martin Eigenbrodt
 *
 *
 *******************************************************************************/ 

package hudson.views;

import hudson.DescriptorExtensionList;
import hudson.Extension;
import hudson.ExtensionPoint;
import hudson.model.Describable;
import hudson.model.Descriptor;
import hudson.model.Descriptor.FormException;
import hudson.model.Hudson;
import hudson.model.Item;
import hudson.model.ItemGroup;
import hudson.model.ListView;
import hudson.model.View;
import hudson.util.DescriptorList;
import org.kohsuke.stapler.export.Exported;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Extension point for adding a column to a table rendering of {@link Item}s,
 * such as {@link ListView}.
 *
 * <p> This object must have the <tt>column.jelly</tt>. This view is called for
 * each cell of this column. The {@link Item} object is passed in the "job"
 * variable. The view should render the <td> tag.
 *
 * <p> This object may have an additional <tt>columHeader.jelly</tt>. The
 * default ColmnHeader will render {@link #getColumnCaption()}.
 *
 * <p> If you opt to
 * {@linkplain ListViewColumnDescriptor#shownByDefault() be shown by default},
 * there also must be a default constructor, which is invoked to create a list
 * view column in the default configuration.
 *
 * <p> Originally, this extension point was designed for {@link ListView}, but
 * since then it has grown to be applicable to other {@link View}s and
 * {@link ItemGroup}s that render a collection of {@link Item}s in a tabular
 * format.
 *
 * @author Kohsuke Kawaguchi
 * @since 1.279
 * @see ListViewColumnDescriptor
 */
public abstract class ListViewColumn implements ExtensionPoint, Describable<ListViewColumn> {

    /**
     * Returns the name of the column that explains what this column means
     *
     * @return The convention is to use capitalization like "Foo Bar Zot".
     */
    @Exported
    public String getColumnCaption() {
        return getDescriptor().getDisplayName();
    }

    /**
     * Returns all the registered {@link ListViewColumn} descriptors.
     */
    public static DescriptorExtensionList<ListViewColumn, Descriptor<ListViewColumn>> all() {
        return Hudson.getInstance().<ListViewColumn, Descriptor<ListViewColumn>>getDescriptorList(ListViewColumn.class);
    }
    /**
     * All registered {@link ListViewColumn}s.
     *
     * @deprecated as of 1.281 Use {@link #all()} for read access and
     * {@link Extension} for registration.
     */
    public static final DescriptorList<ListViewColumn> LIST = new DescriptorList<ListViewColumn>(ListViewColumn.class);

    /**
     * Whether this column will be shown by default. The default implementation
     * is true.
     *
     * @since 1.301
     * @deprecated as of 1.342. Use
     * {@link ListViewColumnDescriptor#shownByDefault()}
     */
    public boolean shownByDefault() {
        return true;
    }

    /**
     * For compatibility reason, this method may not return a
     * {@link ListViewColumnDescriptor} and instead return a plain
     * {@link Descriptor} instance.
     */
    public Descriptor<ListViewColumn> getDescriptor() {
        return Hudson.getInstance().getDescriptorOrDie(getClass());
    }

    /**
     * Creates the list of {@link ListViewColumn}s to be used for newly created
     * {@link ListView}s and their likes.
     *
     * @since 1.391
     */
    public static List<ListViewColumn> createDefaultInitialColumnList() {
        // OK, set up default list of columns:
        // create all instances
        ArrayList<ListViewColumn> r = new ArrayList<ListViewColumn>();
        DescriptorExtensionList<ListViewColumn, Descriptor<ListViewColumn>> all = ListViewColumn.all();
        ArrayList<Descriptor<ListViewColumn>> left = new ArrayList<Descriptor<ListViewColumn>>(all);

        for (Class<? extends ListViewColumn> d : DEFAULT_COLUMNS) {
            Descriptor<ListViewColumn> des = all.find(d);
            if (des != null) {
                try {
                    r.add(des.newInstance(null, null));
                    left.remove(des);
                } catch (FormException e) {
                    LOGGER.log(Level.WARNING, "Failed to instantiate " + des.clazz, e);
                }
            }
        }
        for (Descriptor<ListViewColumn> d : left) {
            try {
                if (d instanceof ListViewColumnDescriptor) {
                    ListViewColumnDescriptor ld = (ListViewColumnDescriptor) d;
                    if (!ld.shownByDefault()) {
                        continue;   // skip this
                    }
                }
                ListViewColumn lvc = d.newInstance(null, null);
                if (!lvc.shownByDefault()) {
                    continue; // skip this
                }
                r.add(lvc);
            } catch (FormException e) {
                LOGGER.log(Level.WARNING, "Failed to instantiate " + d.clazz, e);
            }
        }

        return r;
    }
    /**
     * Traditional column layout before the {@link ListViewColumn} becomes
     * extensible.
     */
    private static final List<Class<? extends ListViewColumn>> DEFAULT_COLUMNS = Arrays.asList(
            StatusColumn.class,
            WeatherColumn.class,
            JobColumn.class,
            LastSuccessColumn.class,
            LastFailureColumn.class,
            LastDurationColumn.class,
            ConsoleColumn.class,
            BuildButtonColumn.class);
    private static final Logger LOGGER = Logger.getLogger(ListViewColumn.class.getName());
}