/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * 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 com.android.providers.calendar;

import android.net.Uri;

public class QueryParameterUtils {

    public static boolean readBooleanQueryParameter(Uri uri, String name,
            boolean defaultValue) {
        final String flag = getQueryParameter(uri, name);
        return flag == null
                ? defaultValue
                : (!"false".equals(flag.toLowerCase()) && !"0".equals(flag.toLowerCase()));
    }

    // Duplicated from ContactsProvider2.
    /**
     * A fast re-implementation of {@link android.net.Uri#getQueryParameter}
     */
    public static String getQueryParameter(Uri uri, String parameter) {
        String query = uri.getEncodedQuery();
        if (query == null) {
            return null;
        }

        int queryLength = query.length();
        int parameterLength = parameter.length();

        String value;
        int index = 0;
        while (true) {
            index = query.indexOf(parameter, index);
            if (index == -1) {
                return null;
            }

            index += parameterLength;

            if (queryLength == index) {
                return null;
            }

            if (query.charAt(index) == '=') {
                index++;
                break;
            }
        }

        int ampIndex = query.indexOf('&', index);
        if (ampIndex == -1) {
            value = query.substring(index);
        } else {
            value = query.substring(index, ampIndex);
        }

        return Uri.decode(value);
    }
}