/*
 * 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.content.Context;
import android.database.Cursor;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.ListView;

import net.micode.notes.data.Notes;
import net.micode.notes.data.Notes.NoteColumns;
import net.micode.notes.ui.NotesListItem.NoteItemData;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

// ... existing code ...

/**
 * 笔记列表适配器
 *
 * 【功能说明】
 * 1. 继承CursorAdapter，用于在ListView中显示笔记列表
 * 2. 支持多选模式，可批量操作笔记
 * 3. 管理选中状态和桌面小部件信息
 * 4. 自动统计笔记和文件夹数量
 */
public class NotesListAdapter extends CursorAdapter {
    private Context mContext;
    private Map<Long, Boolean> mSelectedIndex;
    private int mChoiceMode;
    private int mCount;

    /**
     * 桌面小部件属性类
     * 用于存储小部件的ID和类型信息
     */
    public static class AppWidgetAttribute {
        public int widgetId;
        public int widgetType;
    }

    // 这里的索引顺序必须和 PROJECTION 数组完全一致
    private static final int ID = 0;
    private static final int SNIPPET = 1;
    private static final int TYPE = 2;
    private static final int MODIFIED_DATE = 3;
    private static final int ALERT_DATE = 4;
    private static final int BG_COLOR_ID = 5;
    private static final int PARENT_ID = 7;

    // 查询投影：包含笔记列表显示所需的所有字段
    public static final String[] PROJECTION = {
            NoteColumns.ID,
            NoteColumns.SNIPPET,
            NoteColumns.TYPE,
            NoteColumns.MODIFIED_DATE,
            NoteColumns.ALERTED_DATE,
            NoteColumns.BG_COLOR_ID,
            NoteColumns.HAS_ATTACHMENT,
            NoteColumns.PARENT_ID
    };

    /**
     * 构造函数
     * @param context 上下文对象
     */
    public NotesListAdapter(Context context) {
        super(context, null);
        mSelectedIndex = new HashMap<>();
        mContext = context;
        mChoiceMode = 0;
    }

    @Override
    public void changeCursor(Cursor cursor) {
        super.changeCursor(cursor);
        mCount = 0;
        if (cursor != null) {
            mCount = cursor.getCount();
        }
        // 切换游标时清空选中状态
        mSelectedIndex.clear();
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        return new NotesListItem(mContext);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        if (view instanceof NotesListItem) {
            NoteItemData itemData = new NoteItemData(context, cursor);
            ((NotesListItem) view).bind(context, itemData, mChoiceMode == ListView.CHOICE_MODE_MULTIPLE,
                    mSelectedIndex.containsKey(itemData.getId()) ? mSelectedIndex.get(itemData.getId()) : false);
        }
    }

    /**
     * 设置指定位置的笔记为选中或非选中状态
     * @param position 列表位置
     * @param checked true表示选中，false表示取消选中
     */
    public void setCheckedItem(final int position, final boolean checked) {
        Cursor c = getCursor();
        if (c.moveToPosition(position)) {
            long id = c.getLong(ID);
            if (id >= 0) {
                mSelectedIndex.put(id, checked);
            }
        }
        notifyDataSetChanged();
    }

    /**
     * 设置选择模式
     * @param mode 选择模式（单选/多选/无）
     */
    public void setChoiceMode(int mode) {
        mChoiceMode = mode;
        // 如果不是多选模式，清空选中状态
        if (mChoiceMode != ListView.CHOICE_MODE_MULTIPLE) {
            mSelectedIndex.clear();
        }
    }

    /**
     * 判断是否所有笔记都被选中
     * @return true表示全部选中
     */
    public boolean isAllSelected() {
        int selectedCount = mSelectedIndex.size();
        return selectedCount == mCount && selectedCount > 0;
    }

    /**
     * 全选或全不选
     * @param checked true表示全选，false表示全不选
     */
    public void selectAll(boolean checked) {
        Cursor c = getCursor();
        mSelectedIndex.clear();
        if (c != null) {
            for (int i = 0; i < c.getCount(); i++) {
                if (c.moveToPosition(i)) {
                    long id = c.getLong(ID);
                    if (id >= 0) {
                        mSelectedIndex.put(id, checked);
                    }
                }
            }
        }
        notifyDataSetChanged();
    }

    /**
     * 获取已选中的笔记数量
     * @return 选中数量
     */
    public int getSelectedCount() {
        return mSelectedIndex.size();
    }

    /**
     * 获取所有已选中笔记的ID集合
     * @return 笔记ID集合
     */
    public HashSet<Long> getSelectedItemIds() {
        HashSet<Long> ids = new HashSet<>();
        for (Map.Entry<Long, Boolean> entry : mSelectedIndex.entrySet()) {
            if (entry.getValue()) {
                ids.add(entry.getKey());
            }
        }
        return ids;
    }

    /**
     * 获取所有已选中笔记关联的桌面小部件信息
     * @return 小部件属性集合
     */
    public HashSet<AppWidgetAttribute> getSelectedWidget() {
        HashSet<AppWidgetAttribute> widgets = new HashSet<>();
        Cursor c = getCursor();
        if (c != null) {
            int widgetIdIdx = c.getColumnIndex(NoteColumns.WIDGET_ID);
            int widgetTypeIdx = c.getColumnIndex(NoteColumns.TYPE);

            for (int i = 0; i < c.getCount(); i++) {
                if (c.moveToPosition(i)) {
                    long id = c.getLong(ID);
                    if (mSelectedIndex.containsKey(id) && mSelectedIndex.get(id)) {
                        AppWidgetAttribute widget = new AppWidgetAttribute();
                        if (widgetIdIdx >= 0) widget.widgetId = c.getInt(widgetIdIdx);
                        if (widgetTypeIdx >= 0) widget.widgetType = c.getInt(widgetTypeIdx);
                        widgets.add(widget);
                    }
                }
            }
        }
        return widgets;
    }

    @Override
    public NoteItemData getItem(int position) {
        Cursor c = getCursor();
        if (c.moveToPosition(position)) {
            return new NoteItemData(mContext, c);
        }
        return null;
    }
}