/*
 * Copyright 2011 Instituto Superior Tecnico
 * 
 *      https://fenix-ashes.ist.utl.pt/
 * 
 *   This file is part of the vaadin-framework.
 *
 *   The vaadin-framework Infrastructure is free software: you can
 *   redistribute it and/or modify it under the terms of the GNU Lesser General
 *   Public License as published by the Free Software Foundation, either version
 *   3 of the License, or (at your option) any later version.*
 *
 *   vaadin-framework is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *   GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with vaadin-framework. If not, see <http://www.gnu.org/licenses/>.
 * 
 */
package pt.ist.vaadinframework.fragment;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang.StringUtils;

import pt.ist.vaadinframework.annotation.EmbeddedComponent;
import pt.ist.vaadinframework.annotation.EmbeddedComponentUtils;
import pt.ist.vaadinframework.ui.EmbeddedComponentContainer;

/**
 * @author Sérgio Silva (sergio.silva@ist.utl.pt)
 * 
 */
public class FragmentQuery implements Serializable {
    String path;

    Map<String, String> params;

    private void setParams(String query) {
        final String[] args = query.split("&");
        for (String param : args) {
            final String[] split = param.split("=");
            if (split.length == 2) {
                String name = split[0];
                String value = split[1];
                put(name, value);
            } else {
                throw new InvalidFragmentException(query);
            }
        }
    }

    private void setPath(final String path) {
        this.path = path;
    }

    public FragmentQuery() {
        // params = new HashMap<String, String>();
    }

    public void put(String key, String value) {
        if (params == null) {
            params = new HashMap<>();
        }
        params.put(key, value);
    }

    public FragmentQuery(Class<? extends EmbeddedComponentContainer> clazz, String... values) {
        this();
        final EmbeddedComponent annotation = EmbeddedComponentUtils.getAnnotation(clazz);
        final String[] path = annotation.path();
        final String[] args = annotation.args();

        if (args.length < values.length || path.length != 1) {
            throw new InvalidFragmentException("args don't match");
        }

        this.path = path[0];

        for (int i = 0; i < values.length; i++) {
            if (values[i] != null) {
                put(args[i], values[i]);
            }
        }
    }

    public FragmentQuery(String fragment) {
        this();
        if (fragment == null || fragment.isEmpty() || !fragment.startsWith("#")) {
            path = null;
            params = null;
            throw new InvalidFragmentException();
        }

        if (!fragment.contains("?")) {
            path = fragment.substring(1);
            params = null;
            return;
        }

        final Pattern compile = Pattern.compile("^\\#(.*)\\?(.*)?$");
        final Matcher matcher = compile.matcher(fragment);
        if (matcher.matches() && matcher.groupCount() == 2) {
            setPath(matcher.group(1));
            setParams(matcher.group(2));
        }
    }

    public String getPath() {
        return path;
    }

    public Map<String, String> getParams() {
        return params != null ? params : Collections.EMPTY_MAP;
    }

    public String getQueryString() {
        String queryString = String.format("%s", path);
        final ArrayList<String> args = new ArrayList<String>();
        if (params != null) {
            for (Entry<String, String> entry : params.entrySet()) {
                args.add(String.format("%s=%s", entry.getKey(), entry.getValue()));
            }
        }
        return args.isEmpty() ? queryString : queryString + "?" + StringUtils.join(args, "&");
    }
}