/*
 * Copyright 2014 Red Hat Inc. and/or its affiliates and other contributors.
 *
 * 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 org.switchyard.deploy.karaf;

import java.util.Arrays;
import java.util.List;

import org.apache.felix.service.command.CommandSession;
import org.apache.karaf.shell.console.Completer;
import org.apache.karaf.shell.console.completer.ArgumentCompleter;
import org.apache.karaf.shell.console.completer.StringsCompleter;
import org.apache.karaf.shell.console.jline.CommandSessionHolder;
import org.switchyard.admin.Application;
import org.switchyard.admin.Reference;
import org.switchyard.admin.Service;
import org.switchyard.admin.SwitchYard;

/**
 * Generates completion set for Application arguments.
 */
public class ResetMetricsPatternCompleter implements Completer {

    private SwitchYard _switchYard;

    @Override
    public int complete(String buffer, int cursor, List<String> candidates) {
        final StringsCompleter delegate = new StringsCompleter();
        final ResetMetricsCommand.SearchType type = getType();
        switch (type) {
        case application:
            for (Application application : _switchYard.getApplications()) {
                delegate.getStrings().add(application.getName().toString());
            }
            break;
        case service:
            for (Service service : _switchYard.getServices()) {
                delegate.getStrings().add(service.getName().toString());
            }
            break;
        case reference:
            for (Reference reference : _switchYard.getReferences()) {
                delegate.getStrings().add(reference.getName().toString());
            }
            break;
        default:
            break;
        }
        return delegate.complete(buffer, cursor, candidates);
    }

    /**
     * @param switchYard the SwitchYard admin service
     */
    public void setSwitchYard(SwitchYard switchYard) {
        _switchYard = switchYard;
    }

    private ResetMetricsCommand.SearchType getType() {
        final CommandSession session = CommandSessionHolder.getSession();
        if (session == null) {
            return null;
        }
        final ArgumentCompleter.ArgumentList argList = (ArgumentCompleter.ArgumentList) session
                .get(ArgumentCompleter.ARGUMENTS_LIST);
        if (argList == null || argList.getArguments() == null || argList.getArguments().length == 0) {
            return null;
        }
        final List<String> arguments = Arrays.asList(argList.getArguments());
        int argumentOffset = 1; // command is first argument
        for (int index = 0, count = arguments.size(); index < count; ++index) {
            if (arguments.get(index).startsWith("-")) {
                argumentOffset = index;
            }
        }
        if (argumentOffset < arguments.size()) {
            return ResetMetricsCommand.SearchType.valueOf(arguments.get(argumentOffset));
        }
        return null;
    }

}