/*
 * 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.
 */
// 该类定义了访问本地 SQLite 数据库中笔记数据表的方法
package net.micode.notes.gtask.data;

import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
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.data.NotesDatabaseHelper.TABLE;
import net.micode.notes.gtask.exception.ActionFailureException;

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


public class SqlData {
    private static final String TAG = SqlData.class.getSimpleName();// 日志 TAG

    private static final int INVALID_ID = -99999;// 无效的数据 ID

    public static final String[] PROJECTION_DATA = new String[] {// 数据表中常用的列
            DataColumns.ID, DataColumns.MIME_TYPE, DataColumns.CONTENT, DataColumns.DATA1,
            DataColumns.DATA3
    };

    public static final int DATA_ID_COLUMN = 0;

    public static final int DATA_MIME_TYPE_COLUMN = 1;

    public static final int DATA_CONTENT_COLUMN = 2;

    public static final int DATA_CONTENT_DATA_1_COLUMN = 3;

    public static final int DATA_CONTENT_DATA_3_COLUMN = 4;

    private ContentResolver mContentResolver;// ContentResolver 用于访问本地数据库

    private boolean mIsCreate;// 是否为新建的数据

    private long mDataId; // 数据的各个列的值

    private String mDataMimeType;

    private String mDataContent;

    private long mDataContentData1;

    private String mDataContentData3;

    private ContentValues mDiffDataValues; // 修改时的差异数据

    public SqlData(Context context) {// 构造方法1：用于新建数据
        mContentResolver = context.getContentResolver();
        mIsCreate = true;
        mDataId = INVALID_ID;
        mDataMimeType = DataConstants.NOTE;
        mDataContent = "";
        mDataContentData1 = 0;
        mDataContentData3 = "";
        mDiffDataValues = new ContentValues();
    }

    public SqlData(Context context, Cursor c) {// 构造方法2：用于从数据库中读取数据
        mContentResolver = context.getContentResolver();
        mIsCreate = false;
        loadFromCursor(c);
        mDiffDataValues = new ContentValues();
    }

    private void loadFromCursor(Cursor c) {// 从 Cursor 中读取数据
        mDataId = c.getLong(DATA_ID_COLUMN);
        mDataMimeType = c.getString(DATA_MIME_TYPE_COLUMN);
        mDataContent = c.getString(DATA_CONTENT_COLUMN);
        mDataContentData1 = c.getLong(DATA_CONTENT_DATA_1_COLUMN);
        mDataContentData3 = c.getString(DATA_CONTENT_DATA_3_COLUMN);
    }

<<<<<<< HEAD
    public void setContent(JSONObject js) throws JSONException {
=======
    public void setContent(JSONObject js) throws JSONException {//建立连接
            mDiffDataValues.put(DataColumns.ID, dataId);
        mDataId = dataId;

        String dataMimeType = js.has(DataColumns.MIME_TYPE) ? js.getString(DataColumns.MIME_TYPE)
                : DataConstants.NOTE;
        if (mIsCreate || !mDataMimeType.equals(dataMimeType)) {
            mDiffDataValues.put(DataColumns.MIME_TYPE, dataMimeType);
        }
        mDataMimeType = dataMimeType;

        String dataContent = js.has(DataColumns.CONTENT) ? js.getString(DataColumns.CONTENT) : "";
        if (mIsCreate || !mDataContent.equals(dataContent)) {
            mDiffDataValues.put(DataColumns.CONTENT, dataContent);
        }
        mDataContent = dataContent;

        long dataContentData1 = js.has(DataColumns.DATA1) ? js.getLong(DataColumns.DATA1) : 0;
        if (mIsCreate || mDataContentData1 != dataContentData1) {
            mDiffDataValues.put(DataColumns.DATA1, dataContentData1);
        }
        mDataContentData1 = dataContentData1;

        String dataContentData3 = js.has(DataColumns.DATA3) ? js.getString(DataColumns.DATA3) : "";
        if (mIsCreate || !mDataContentData3.equals(dataContentData3)) {
            mDiffDataValues.put(DataColumns.DATA3, dataContentData3);
        }
        mDataContentData3 = dataContentData3;
    }

    public JSONObject getContent() throws JSONException {
        if (mIsCreate) {
            Log.e(TAG, "it seems that we haven't created this in database yet");
            return null;
        }
        JSONObject js = new JSONObject();
        js.put(DataColumns.ID, mDataId);
        js.put(DataColumns.MIME_TYPE, mDataMimeType);
        js.put(DataColumns.CONTENT, mDataContent);
        js.put(DataColumns.DATA1, mDataContentData1);
        js.put(DataColumns.DATA3, mDataContentData3);
        return js;
    }

<<<<<<< HEAD
    public void commit(long noteId, boolean validateVersion, long version) {

=======
    public void commit(long noteId, boolean validateVersion, long version) {//提交数据更改
        /* 如果 mIsCreate 为 true，表示正在创建新的笔记。
        在这种情况下，首先会检查 mDataId 是否为无效值，
        如果是，并且 mDiffDataValues 中包含了 DataColumns.ID，
        则会将其移除。然后将 noteId 放入 mDiffDataValues 中，
        并通过 mContentResolver 根据 mDiffDataValues 插入数据到 Notes.CONTENT_DATA_URI 中，
        并获取插入数据的路径信息。最后将路径中的第二个片段转换为 Long 值存储到 mDataId  */
>>>>>>> develop
        if (mIsCreate) {
            if (mDataId == INVALID_ID && mDiffDataValues.containsKey(DataColumns.ID)) {
                mDiffDataValues.remove(DataColumns.ID);
            }

            mDiffDataValues.put(DataColumns.NOTE_ID, noteId);
            Uri uri = mContentResolver.insert(Notes.CONTENT_DATA_URI, mDiffDataValues);
            try {
                mDataId = Long.valueOf(uri.getPathSegments().get(1));
            } catch (NumberFormatException e) {
                Log.e(TAG, "Get note id error :" + e.toString());
                throw new ActionFailureException("create note failed");
            }
<<<<<<< HEAD
        } else {
=======
        } 
        /*如果 mIsCreate 不为 true，表示正在更新现有笔记。
        首先判断 mDiffDataValues 的大小是否大于 0，如果是，
        根据是否需要验证版本号通过 mContentResolver 更新数据。如果不需要验证版本号，
        则直接根据 mDataId 更新数据；如果需要验证版本号，
        则使用 NoteColumns.ID 和 NoteColumns.VERSION 字段进行联合查询，
        并以 noteId 和 version 的值作为参数，通过 mContentResolver 更新数据。
        更新完成后，如果结果为 0，表示没有更新成功 */
        else {
>>>>>>> develop
            if (mDiffDataValues.size() > 0) {
                int result = 0;
                if (!validateVersion) {
                    result = mContentResolver.update(ContentUris.withAppendedId(
                            Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues, null, null);
                } else {
                    result = mContentResolver.update(ContentUris.withAppendedId(
                            Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues,
                            " ? in (SELECT " + NoteColumns.ID + " FROM " + TABLE.NOTE
                                    + " WHERE " + NoteColumns.VERSION + "=?)", new String[] {
                                    String.valueOf(noteId), String.valueOf(version)
                            });
                }
                if (result == 0) {
                    Log.w(TAG, "there is no update. maybe user updates note when syncing");
                }
            }
        }

        mDiffDataValues.clear();
        mIsCreate = false;
    }

<<<<<<< HEAD
    public long getId() {
=======
    public long getId() {//获取ID
>>>>>>> develop
        return mDataId;
    }
}