/*
 * Jitsi, the OpenSource Java VoIP and Instant Messaging client.
 *
 * Copyright @ 2015 Atlassian Pty Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.java.sip.communicator.plugin.otr;

import java.util.*;

import org.bouncycastle.util.encoders.Base64; // disambiguation
import org.jitsi.service.configuration.*;

/**
 * A class that gets/sets the OTR configuration values. Introduced to assure our
 * configuration is properly written when <tt>XMLConfigurationStore</tt> is
 * used. Can be seen as a proxy between the {@link ConfigurationService} and the
 * OTR Plugin.
 *
 * @author George Politis
 */
public class OtrConfigurator
{
    /**
     * Gets an XML tag friendly {@link String} from a {@link String}.
     *
     * @param s a {@link String}
     * @return an XML friendly {@link String}
     */
    private String getXmlFriendlyString(String s)
    {
        if (s == null || s.length() < 1)
            return s;

        // XML Tags are not allowed to start with digits,
        // insert a dummy "p" char.
        if (Character.isDigit(s.charAt(0)))
            s = "p" + s;

        char[] cId = new char[s.length()];

        for (int i = 0; i < cId.length; i++)
        {
            char c = s.charAt(i);

            cId[i] = Character.isLetterOrDigit(c) ? c : '_';
        }

        return new String(cId);
    }

    /**
     * Puts a given property ID under the OTR namespace and makes sure it is XML
     * tag friendly.
     *
     * @param id the property ID.
     * @return the namespaced ID.
     */
    private String getID(String id)
    {
        return
            "net.java.sip.communicator.plugin.otr." + getXmlFriendlyString(id);
    }

    /**
     * Returns the value of the property with the specified name or null if no
     * such property exists ({@link ConfigurationService#getProperty(String)}
     * proxy).
     *
     * @param id of the property that is being queried.
     * @return the <tt>byte[]</tt> value of the property with the specified
     *         name.
     */
    public byte[] getPropertyBytes(String id)
    {
        String value = OtrActivator.configService.getString(getID(id));

        return (value == null) ? null : Base64.decode(value.getBytes());
    }

    /**
     * Gets the value of a specific property as a boolean (
     * {@link ConfigurationService#getBoolean(String, boolean)} proxy).
     *
     * @param id of the property that is being queried.
     * @param defaultValue the value to be returned if the specified property
     *            name is not associated with a value.
     * @return the <tt>Boolean</tt> value of the property with the specified
     *         name.
     */
    public boolean getPropertyBoolean(String id, boolean defaultValue)
    {
        return
            OtrActivator.configService.getBoolean(getID(id), defaultValue);
    }

    /**
     * Sets the property with the specified name to the specified value (
     * {@link ConfigurationService#setProperty(String, Object)} proxy). The
     * value is Base64 encoded.
     *
     * @param id the name of the property to change.
     * @param value the new value of the specified property.
     */
    public void setProperty(String id, byte[] value)
    {
        String valueToStore = new String(Base64.encode(value));

        OtrActivator.configService.setProperty(getID(id), valueToStore);
    }

    /**
     * Sets the property with the specified name to the specified value (
     * {@link ConfigurationService#setProperty(String, Object)} proxy).
     *
     * @param id the name of the property to change.
     * @param value the new value of the specified property.
     */
    public void setProperty(String id, Object value)
    {
        OtrActivator.configService.setProperty(getID(id), value);
    }

    /**
     * Removes the property with the specified name (
     * {@link ConfigurationService#removeProperty(String)} proxy).
     *
     * @param id the name of the property to change.
     */
    public void removeProperty(String id)
    {
        OtrActivator.configService.removeProperty(getID(id));
    }

    /**
     * Gets the value of a specific property as a signed decimal integer.
     *
     * @param id the name of the property to change.
     * @param defaultValue the value to be returned if the specified property
     *            name is not associated with a value.
     * @return the <tt>int</tt> value of the property
     */
    public int getPropertyInt(String id, int defaultValue)
    {
        return OtrActivator.configService.getInt(getID(id), defaultValue);
    }

    /**
     * Appends <tt>value</tt> to the old value of the property with the
     * specified name. The two values will be comma separated.
     * 
     * @param id the name of the property to append to
     * @param value the value to append
     */
    public void appendProperty(String id, Object value)
    {
        Object oldValue = OtrActivator.configService.getProperty(getID(id));

        String newValue =
            oldValue == null ? value.toString() : oldValue + "," + value;

        setProperty(id, newValue);
    }

    public List<String> getAppendedProperties(String id)
    {
        String listProperties =
           (String) OtrActivator.configService.getProperty(getID(id));

        if (listProperties == null) return new ArrayList<String>();

        return Arrays.asList(listProperties.split(","));
    }
}