/*
 * 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.
 */

// 声明包名
package net.micode.notes.ui;

// 导入所需的Android和自定义类
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.ContentUris;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;

import net.micode.notes.data.Notes;
import net.micode.notes.data.Notes.NoteColumns;

// 定义一个继承自BroadcastReceiver的类，用于初始化闹钟
public class AlarmInitReceiver extends BroadcastReceiver {

    // 定义查询数据库时需要的列
    private static final String [] PROJECTION = new String [] {
        NoteColumns.ID, // 笔记的ID
        NoteColumns.ALERTED_DATE // 笔记的提醒日期
    };

    // 定义列索引，用于从Cursor中获取数据
    private static final int COLUMN_ID                = 0; // ID列的索引
    private static final int COLUMN_ALERTED_DATE      = 1; // 提醒日期列的索引

    // 当接收到广播时调用此方法
    @Override
    public void onReceive(Context context, Intent intent) {
        long currentDate = System.currentTimeMillis(); // 获取当前时间
        // 从内容提供者中查询需要提醒的笔记，条件是提醒日期大于当前时间且笔记类型为普通笔记
        Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
                PROJECTION,
                NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE,
                new String[] { String.valueOf(currentDate) },
                null);

        if (c != null) {
            if (c.moveToFirst()) { // 移动到查询结果的第一条记录
                do {
                    long alertDate = c.getLong(COLUMN_ALERTED_DATE); // 获取提醒日期
                    // 创建一个Intent，用于在提醒时间到达时广播
                    Intent sender = new Intent(context, AlarmReceiver.class);
                    // 设置Intent的URI，包含笔记的ID
                    sender.setData(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, c.getLong(COLUMN_ID)));
                    // 创建一个PendingIntent，用于AlarmManager在提醒时间到达时启动
                    PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, sender, 0);
                    // 获取AlarmManager服务
                    AlarmManager alermManager = (AlarmManager) context
                            .getSystemService(Context.ALARM_SERVICE);
                    // 设置闹钟，在提醒时间到达时广播Intent
                    alermManager.set(AlarmManager.RTC_WAKEUP, alertDate, pendingIntent);
                } while (c.moveToNext()); // 处理查询结果中的下一条记录
            }
            c.close(); // 关闭Cursor
        }
    }
}