/*
 * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
 *
 * 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.micode.notes.data;

import android.content.Context;
import android.database.Cursor;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.provider.ContactsContract.Data;
import android.telephony.PhoneNumberUtils;
import android.util.Log;

import java.util.HashMap;

/**
 * 联系人信息查询类
 * 用于根据电话号码从联系人数据库中查询对应的联系人姓名
 * 包含缓存机制以提高查询效率
 */
public class Contact {
    // 联系人缓存，避免重复查询
    private static HashMap<String, String> sContactCache;
    private static final String TAG = "Contact";

    // 联系人查询SQL条件（使用CALLER_ID匹配规则）
    private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER
            + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
            + " AND " + Data.RAW_CONTACT_ID + " IN "
            + "(SELECT raw_contact_id "
            + " FROM phone_lookup"
            + " WHERE min_match = '+')";

    /**
     * 根据电话号码查询联系人姓名
     * @param context 应用上下文
     * @param phoneNumber 待查询的电话号码
     * @return 联系人姓名，未找到返回null
     */
    public static String getContact(Context context, String phoneNumber) {
        // 初始化缓存
        if (sContactCache == null) {
            sContactCache = new HashMap<String, String>();
        }

        // 检查缓存中是否已有结果
        if (sContactCache.containsKey(phoneNumber)) {
            return sContactCache.get(phoneNumber);
        }

        // 生成适配CALLER_ID匹配规则的查询条件
        String selection = CALLER_ID_SELECTION.replace("+",
                PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));

        // 查询联系人数据库
        Cursor cursor = context.getContentResolver().query(
                Data.CONTENT_URI,                  // 数据URI
                new String[] { Phone.DISPLAY_NAME }, // 查询字段（联系人显示名称）
                selection,                           // 查询条件
                new String[] { phoneNumber },        // 条件参数
                null);                               // 排序方式

        if (cursor != null && cursor.moveToFirst()) {
            try {
                // 解析查询结果
                String name = cursor.getString(0);
                // 缓存查询结果
                sContactCache.put(phoneNumber, name);
                return name;
            } catch (IndexOutOfBoundsException e) {
                Log.e(TAG, "Cursor获取字符串错误: " + e.toString());
                return null;
            } finally {
                // 关闭Cursor释放资源
                cursor.close();
            }
        } else {
            Log.d(TAG, "未找到匹配电话号码: " + phoneNumber);
            return null;
        }
    }
}