READMI/src/notes/gtask/data/Task.java

/*
 * 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.gtask.data;//包名，说明依赖关系。//

import android.database.Cursor;
import android.text.TextUtils;
import android.util.Log;

import net.micode.notes.data.Notes;
import net.micode.notes.data.Notes.DataColumns;
import net.micode.notes.data.Notes.DataConstants;
import net.micode.notes.data.Notes.NoteColumns;
import net.micode.notes.gtask.exception.ActionFailureException;
import net.micode.notes.tool.GTaskStringUtils;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;


public class Task extends Node {//创建Task类（继承父类Node）//
    private static final String TAG = Task.class.getSimpleName();//调用 getSimpleName ()函数来得到类的简写名称并存入字符串TAG中//

    private boolean mCompleted;//以下四个变量用于Task构造，mCompleted判断是否完成//

    private String mNotes;//页面标签信息//

    private JSONObject mMetaInfo;//元数据信息//

    private Task mPriorSibling;//对应的优先兄弟类Task的指针//

    private TaskList mParent;//所在任务列表的指针//

    public Task() {
        super();
        mCompleted = false;
        mNotes = null;
        mPriorSibling = null;
        mParent = null;
        mMetaInfo = null;
    }//Task类的构造函数，对对象进行初始化//

    public JSONObject getCreateAction(int actionId) {
        JSONObject js = new JSONObject();
        //共享数据存入动作类型//
        try {
            // action_type
            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_CREATE);//存入当前task的指针//

            // action_id
            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);//设置活动的id//

            // index
            js.put(GTaskStringUtils.GTASK_JSON_INDEX, mParent.getChildTaskIndex(this));//设置索引//

            // entity_delta
            JSONObject entity = new JSONObject();//新建一个 JSONObject 对象打包存放 name，creator id，type task//
            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
            entity.put(GTaskStringUtils.GTASK_JSON_CREATOR_ID, "null");
            entity.put(GTaskStringUtils.GTASK_JSON_ENTITY_TYPE,
                    GTaskStringUtils.GTASK_JSON_TYPE_TASK);
            if (getNotes() != null) {
                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
            }//如果存在 notes ，则将其也放入 entity 中//
            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);//这里将entity变量（属于JSONObject类）作为一个数据存放进js变量中//

            // parent_id
            js.put(GTaskStringUtils.GTASK_JSON_PARENT_ID, mParent.getGid());//目的父id的类型//

            // dest_parent_type
            js.put(GTaskStringUtils.GTASK_JSON_DEST_PARENT_TYPE
                    GTaskStringUtils.GTASK_JSON_TYPE_GROUP);//更新列表，id存入父id//

            // list_id
            js.put(GTaskStringUtils.GTASK_JSON_LIST_ID, mParent.getGid());//存入列表id//

            // prior_sibling_id
            if (mPriorSibling != null) {
                js.put(GTaskStringUtils.GTASK_JSON_PRIOR_SIBLING_ID, mPriorSibling.getGid());
            }//如果存在优先兄弟 task，则将其 id 放入 js 中//

        } catch (JSONException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
            throw new ActionFailureException("fail to generate task-create jsonobject");
        }//抛出异常处理机制//

        return js;
    }//对操作号即actionId 进行一些操作的公用函数//

    //此函数和上一个getCreatAction（）的功能差不多，一个是creat，一个updata，都是对action进行操作//
    public JSONObject getUpdateAction(int actionId) {
        JSONObject js = new JSONObject();

        try {
            // action_type
            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_UPDATE);

            // action_id
            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);

            // id
            js.put(GTaskStringUtils.GTASK_JSON_ID, getGid());

            // entity_delta
            JSONObject entity = new JSONObject();
            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
            if (getNotes() != null) {
                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
            }
            entity.put(GTaskStringUtils.GTASK_JSON_DELETED, getDeleted());
            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);

        } catch (JSONException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
            throw new ActionFailureException("fail to generate task-update jsonobject");
        }//异常处理//

        return js;
    }

    //通过云端传输的数据设置内容//
    public void setContentByRemoteJSON(JSONObject js) {
        if (js != null) {
            try {
                // id
                if (js.has(GTaskStringUtils.GTASK_JSON_ID)) {
                    setGid(js.getString(GTaskStringUtils.GTASK_JSON_ID));
                }//如果传入的任务变量不是空的，那就说明有任务，设置修改；否则不用执行//

                // last_modified
                if (js.has(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED)) {
                    setLastModified(js.getLong(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED));
                }//设置last_modified//

                // name
                if (js.has(GTaskStringUtils.GTASK_JSON_NAME)) {
                    setName(js.getString(GTaskStringUtils.GTASK_JSON_NAME));
                }//设置name//

                // notes
                if (js.has(GTaskStringUtils.GTASK_JSON_NOTES)) {
                    setNotes(js.getString(GTaskStringUtils.GTASK_JSON_NOTES));
                }//设置notes//

                // deleted
                if (js.has(GTaskStringUtils.GTASK_JSON_DELETED)) {
                    setDeleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_DELETED));
                }

                // completed
                if (js.has(GTaskStringUtils.GTASK_JSON_COMPLETED)) {
                    setCompleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_COMPLETED));
                }//异常处理//
            } catch (JSONException e) {
                Log.e(TAG, e.toString());
                e.printStackTrace();
                throw new ActionFailureException("fail to get task content from jsonobject");
            }//异常处理，并抛出异常//
        }
    }

    //通过本地的jsonobject获取内容//
    public void setContentByLocalJSON(JSONObject js) {
        if (js == null || !js.has(GTaskStringUtils.META_HEAD_NOTE)
                || !js.has(GTaskStringUtils.META_HEAD_DATA)) {
            Log.w(TAG, "setContentByLocalJSON: nothing is avaiable");
        }

        try {
            JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
            JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);

            if (note.getInt(NoteColumns.TYPE) != Notes.TYPE_NOTE) {
                Log.e(TAG, "invalid type");
                return;
            }/*如果js不存在或者js没有元数据的开头或者js指针没有元数据，那么反馈给用户出错信息*/

            for (int i = 0; i < dataArray.length(); i++) {
                JSONObject data = dataArray.getJSONObject(i);
                if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
                    setName(data.getString(DataColumns.CONTENT));
                    break;
                }
            }//遍历 dataArray 查找与数据库中DataConstants.NOTE 记录信息一致的 data//

        } catch (JSONException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
        }//异常处理操作，打印堆栈痕迹//
    }

    //通过内容更新本地的jsonobject//
    public JSONObject getLocalJSONFromContent() {
        String name = getName();
        try {
            if (mMetaInfo == null) {
                // new task created from web
                if (name == null) {
                    Log.w(TAG, "the note seems to be an empty one");
                    return null;
                }//元数据类型信息为空，若名字也为空则新建一个 JSONObject 对象并将其返回//

                JSONObject js = new JSONObject();//初始化四个指针//
                JSONObject note = new JSONObject();
                JSONArray dataArray = new JSONArray();
                JSONObject data = new JSONObject();
                data.put(DataColumns.CONTENT, name);
                dataArray.put(data);
                js.put(GTaskStringUtils.META_HEAD_DATA, dataArray);//如果存在，那么进行更新本地信息并推送//
                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
                js.put(GTaskStringUtils.META_HEAD_NOTE, note);//获取metainfo中的head_note//
                return js;
            } else {
                // synced task
                JSONObject note = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);//同步任务//
                JSONArray dataArray = mMetaInfo.getJSONArray(GTaskStringUtils.META_HEAD_DATA);// 定义一个数组并进行初始化//

                for (int i = 0; i < dataArray.length(); i++) {
                    JSONObject data = dataArray.getJSONObject(i);
                    if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
                        data.put(DataColumns.CONTENT, getName());
                        break;
                    }
                }//遍历 dataArray 查找与数据库中DataConstants.NOTE 记录信息一致的 data//

                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
                return mMetaInfo;
            }
        } catch (JSONException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
            return null;
        }//异常处理并抛出//
    }

    public void setMetaInfo(MetaData metaData) {
        if (metaData != null && metaData.getNotes() != null) {
            try {
                mMetaInfo = new JSONObject(metaData.getNotes());
            } catch (JSONException e) {
                Log.w(TAG, e.toString());
                mMetaInfo = null;
            }//抛出异常信息并将元数据信息置空//
        }//如果元数据非空且其 notes 非空，则修改元数据类型信息//
    }//设置元数据信息//

    //设置同步action//
    public int getSyncAction(Cursor c) {
        try {
            JSONObject noteInfo = null;
            if (mMetaInfo != null && mMetaInfo.has(GTaskStringUtils.META_HEAD_NOTE)) {
                noteInfo = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
            }/*异常处理，进行同步操作，如果不成功按照对应的情况进行异常信息的反馈，比如远端文档被删除、文档不匹配等等*/

            if (noteInfo == null) {
                Log.w(TAG, "it seems that note meta has been deleted");
                return SYNC_ACTION_UPDATE_REMOTE;
            }//云端便签 id 已被删除，不存在，返回更新本地数据的同步行为//

            if (!noteInfo.has(NoteColumns.ID)) {
                Log.w(TAG, "remote note id seems to be deleted");
                return SYNC_ACTION_UPDATE_LOCAL;
            }//便签 id 不匹配，返回更新本地数据的同步行为//

            // validate the note id now
            if (c.getLong(SqlNote.ID_COLUMN) != noteInfo.getLong(NoteColumns.ID)) {
                Log.w(TAG, "note id doesn't match");
                return SYNC_ACTION_UPDATE_LOCAL;
            }//代码块：信息不匹配//

            if (c.getInt(SqlNote.LOCAL_MODIFIED_COLUMN) == 0) {
                // there is no local update
                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
                    // no update both side
                    return SYNC_ACTION_NONE;
                } else {
                    // apply remote to local
                    return SYNC_ACTION_UPDATE_LOCAL;
                }/*判断修改后的ID匹配是否成功，成功则返回无同步操作，未成功则应用云端到本地，返回本地同步更新操作*/
            } else {
                // validate gtask id
                if (!c.getString(SqlNote.GTASK_ID_COLUMN).equals(getGid())) {
                    Log.e(TAG, "gtask id doesn't match");
                    return SYNC_ACTION_ERROR;
                }//判断gtask的id与获取的id是否匹配//
                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
                    // local modification only
                    return SYNC_ACTION_UPDATE_REMOTE;
                } else {
                    return SYNC_ACTION_UPDATE_CONFLICT;
                }//本地id与云端id一致，即更新云端//
            }
        } catch (Exception e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
        }//异常处理//

        return SYNC_ACTION_ERROR;
    }

    public boolean isWorthSaving() {
        return mMetaInfo != null || (getName() != null && getName().trim().length() > 0)
                || (getNotes() != null && getNotes().trim().length() > 0);
    }//判断是否值得存放//

    public void setCompleted(boolean completed) {
        this.mCompleted = completed;
    }//设置是否完成的标志//

    public void setNotes(String notes) {
        this.mNotes = notes;
    }//设定是note成员变量//

    public void setPriorSibling(Task priorSibling) {
        this.mPriorSibling = priorSibling;
    }//设置这个任务的优先兄弟//

    public void setParent(TaskList parent) {
        this.mParent = parent;
    }//设置父节点列表//

    public boolean getCompleted() {
        return this.mCompleted;
    }//获取 task 是否修改完毕的记录//

    public String getNotes() {
        return this.mNotes;
    }//获取成员变量 mNotes 的信息//

    public Task getPriorSibling() {
        return this.mPriorSibling;
    }//获取优先兄弟列表//

    public TaskList getParent() {
        return this.mParent;
    }//获取父节点列表//

}