/*
 * 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.ui;

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;

/**
 * 闹钟初始化接收器，负责在系统启动后重新设置所有待提醒的闹钟
 * 当设备重启或应用安装后，会触发该接收器，重新注册所有已设置的闹钟提醒
 */
public class AlarmInitReceiver extends BroadcastReceiver {

    // 查询笔记数据时需要的字段
    private static final String [] PROJECTION = new String [] {
            NoteColumns.ID,         // 笔记ID
            NoteColumns.ALERTED_DATE // 提醒日期
    };

    // 字段索引常量，方便从Cursor中获取数据
    private static final int COLUMN_ID                = 0;
    private static final int COLUMN_ALERTED_DATE      = 1;

    @Override
    public void onReceive(Context context, Intent intent) {
        // 获取当前系统时间
        long currentDate = System.currentTimeMillis();

        // 查询所有设置了提醒且提醒时间在当前时间之后的笔记
        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);

        // 遍历查询结果，为每个笔记设置闹钟提醒
        if (c != null) {
            if (c.moveToFirst()) {
                do {
                    // 获取笔记的提醒日期
                    long alertDate = c.getLong(COLUMN_ALERTED_DATE);

                    // 创建一个Intent，用于在闹钟触发时启动AlarmReceiver
                    Intent sender = new Intent(context, AlarmReceiver.class);
                    // 设置Intent的数据URI，包含笔记ID
                    sender.setData(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, c.getLong(COLUMN_ID)));

                    // 创建PendingIntent，用于在将来某个时间点执行Intent
                    PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, sender, 0);

                    // 获取AlarmManager系统服务
                    AlarmManager alarmManager = (AlarmManager) context
                            .getSystemService(Context.ALARM_SERVICE);

                    // 设置闹钟，使用RTC_WAKEUP类型确保在指定时间唤醒设备并触发提醒
                    alarmManager.set(AlarmManager.RTC_WAKEUP, alertDate, pendingIntent);
                } while (c.moveToNext());
            }
            // 关闭Cursor释放资源
            c.close();
        }
    }
}
