using System;
using System.Collections.Generic;
using Mesnac.Basic;
using System.Text;
using System.Windows.Forms;

using ICSharpCode.Data.Core;
using ICSharpCode.Data.Core.Common;
using ICSharpCode.Data.Core.DatabaseDrivers.SQLServer;
using ICSharpCode.Data.Core.Interfaces;
using ICSharpCode.Data.Core.DatabaseObjects;
using ICSharpCode.Data.Core.Enums;
using ICSharpCode.Data.Core.Interfaces;

namespace Mesnac.Gui.Edit.Common
{
    public delegate void CallBackDelegate();        //回调方法
    /// <summary>
    /// 数据源工厂
    /// </summary>
    public class DataSourceFactory
    {
        private static DataSourceFactory instance = null;           //保存工厂实例
        private Dictionary<string, DataSourceItem> _dataSources = null;         //保存数据源
        private TreeNode root = null;
        public event EventHandler DataSourceRefresh;

        private DataSourceFactory()
        {
            this.root = new TreeNode();
            root.Text = "数据源列表";
        }
        /// <summary>
        /// 工厂实例
        /// </summary>
        public static DataSourceFactory Instance
        {
            get
            {
                if (instance == null)
                {
                    instance = new DataSourceFactory();
                }
                return instance;
            }
        }
        /// <summary>
        /// 把内存中的数据源数据保存只文件
        /// </summary>
        /// <param name="fileName">要保存数据源信息的文件名</param>
        public void RefreshDataFromFile(string fileName, params CallBackDelegate[] callBack)
        {
            if (System.IO.File.Exists(fileName))
            {
                this._dataSources = XmlHandler.ParseFromDataSourceXml(fileName);
                //触发事件
                if (DataSourceRefresh != null)
                {
                    DataSourceRefresh(this, EventArgs.Empty);
                }
                new System.Threading.Thread(new System.Threading.ThreadStart(delegate() { this.GenerateDataSourceTree(); foreach (CallBackDelegate call in callBack) { call(); } })).Start();   //异步生成数据源树
            }
            else
            {
                this._dataSources = new Dictionary<string, DataSourceItem>();
            }
        }
        /// <summary>
        /// 把文件中的内容读取至内存
        /// </summary>
        /// <param name="fileName">保存数据源信息的文件名</param>
        public void RefreshDataToFile(string fileName, params CallBackDelegate[] callBack)
        {
            if (this._dataSources != null)
            {
                XmlHandler.GenerateDataSourceXml(this._dataSources, fileName);
                new System.Threading.Thread(new System.Threading.ThreadStart(delegate() { this.GenerateDataSourceTree(); foreach (CallBackDelegate call in callBack) { call(); } })).Start();   //异步生成数据源树
            }
        }
        /// <summary>
        /// 数据源信息
        /// </summary>
        public Dictionary<string, DataSourceItem> DataSources
        {
            get
            {
                return this._dataSources;
            }
        }

        /// <summary>
        /// 数据源树
        /// </summary>
        public TreeNode Root
        {
            get { return this.root; }
        }

        /// <summary>
        /// 生成数据源树
        /// </summary>
        public void GenerateDataSourceTree()
        {
            lock (this)
            {
                this.root.Nodes.Clear();
                this.root = new TreeNode();
                this.root.Text = "数据源列表";
                if (this._dataSources != null)
                {
                    TreeNode nodeDataSource = null;
                    int cnt = 0;
                    foreach (DataSourceItem dataSourceItem in this._dataSources.Values)
                    {
                        nodeDataSource = new TreeNode();
                        nodeDataSource.Text = dataSourceItem.Name;
                        nodeDataSource.ToolTipText = dataSourceItem.Driver;
                        //string driverAssembly = dataSourceItem.DriverAssembly;
                        //string driverClass = dataSourceItem.DriverClass;
                        #region 数据源处理
                        switch (dataSourceItem.Driver)
                        {
                            case "MS SQL Server":
                                SQLServerDatabaseDriver driver = new SQLServerDatabaseDriver();
                                SQLServerDatasource ds = new SQLServerDatasource(driver);
                                ds.Name = dataSourceItem.Server;
                                ds.UserId = dataSourceItem.UserName;
                                ds.Password = dataSourceItem.Password;
                                driver.PopulateDatabases(ds);
                                IDatabase database = null;
                                foreach (IDatabase db in ds.Databases)
                                {
                                    if (db.ToString() == dataSourceItem.Database)
                                    {
                                        database = db;
                                        break;
                                    }
                                }
                                if (database != null)
                                {
                                    database.LoadDatabase();
                                    TreeNode nodeTables = new TreeNode();
                                    nodeTables.Text = "数据表";
                                    TreeNode nodeTable = null;
                                    foreach (ITable table in database.Tables)
                                    {
                                        nodeTable = new TreeNode();
                                        nodeTable.Text = table.TableName;

                                        TreeNode nodeColumn = null;
                                        foreach (IColumn col in table.Items)
                                        {
                                            nodeColumn = new TreeNode();
                                            nodeColumn.Text = col.Name;
                                            nodeTable.Nodes.Add(nodeColumn);
                                        }

                                        nodeTables.Nodes.Add(nodeTable);
                                    }

                                    TreeNode nodeViews = new TreeNode();
                                    nodeViews.Text = "数据视图";
                                    TreeNode nodeView = null;
                                    foreach (IView view in database.Views)
                                    {
                                        nodeView = new TreeNode();
                                        nodeView.Text = view.Name;
                                        TreeNode nodeColumn = null;
                                        foreach (IColumn col in view.Items)
                                        {
                                            nodeColumn = new TreeNode();
                                            nodeColumn.Text = col.Name;
                                            nodeTable.Nodes.Add(nodeColumn);
                                        }
                                        nodeViews.Nodes.Add(nodeView);
                                    }

                                    TreeNode nodeProcedures = new TreeNode();
                                    nodeProcedures.Text = "存储过程";
                                    TreeNode nodeProcedure = null;
                                    foreach (IProcedure procedure in database.Procedures)
                                    {
                                        nodeProcedure = new TreeNode();
                                        nodeProcedure.Text = procedure.Name;
                                        nodeProcedures.Nodes.Add(nodeProcedure);
                                    }

                                    nodeDataSource.Nodes.Add(nodeTables);
                                    nodeDataSource.Nodes.Add(nodeViews);
                                    nodeDataSource.Nodes.Add(nodeProcedures);
                                }
                                break;
                            default:
                                break;
                        }
                        #endregion

                        cnt++;
                        if (cnt > this._dataSources.Values.Count) break;

                        this.root.Nodes.Add(nodeDataSource);
                    }
                }
            }
        }
        /// <summary>
        /// 添加数据源
        /// </summary>
        /// <param name="name"></param>
        /// <param name="item"></param>
        public void Add(string name, DataSourceItem item)
        {
            if (this._dataSources == null)
            {
                this._dataSources = new Dictionary<string, DataSourceItem>();
            }
            if (!this.IsExists(name))
            {
                this._dataSources.Add(name, item);
                //触发事件
                if (DataSourceRefresh != null)
                {
                    DataSourceRefresh(this, EventArgs.Empty);
                }
            }
        }
        /// <summary>
        /// 移除数据源
        /// </summary>
        /// <param name="name"></param>
        public void Remove(string name)
        {
            if (this.IsExists(name))
            {
                this._dataSources.Remove(name);
                //触发事件
                if (DataSourceRefresh != null)
                {
                    DataSourceRefresh(this, EventArgs.Empty);
                }
            }
        }
        /// <summary>
        /// 修改数据源
        /// </summary>
        /// <param name="name"></param>
        /// <param name="newItem"></param>
        public void Modify(string name, DataSourceItem newItem)
        {
            if (this._dataSources == null)
            {
                this._dataSources = new Dictionary<string, DataSourceItem>();
            }
            if (this.IsExists(name))
            {
                this._dataSources[name] = newItem;
                //触发事件
                if (DataSourceRefresh != null)
                {
                    DataSourceRefresh(this, EventArgs.Empty);
                }
            }
        }
        /// <summary>
        /// 获取下一个可用的数据源名称
        /// </summary>
        /// <returns></returns>
        public string GetNextDataSourceName()
        {
            int i = 1;
            if (this._dataSources == null)
            {
                return "DataSource1";
            }
            else
            {
                while (this._dataSources.ContainsKey("DataSource" + i))
                {
                    i++;
                }
            }
            return "DataSource" + i;
        }
        /// <summary>
        /// 判断指定名称的数据源是否存在
        /// </summary>
        /// <param name="dataSourceName">要判断的数据源名称</param>
        /// <returns>存在返回true，否则返回false</returns>
        public bool IsExists(string dataSourceName)
        {
            if (this._dataSources == null)
            {
                return false;
            }
            else
            {
                if (this._dataSources.ContainsKey(dataSourceName))
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
        }
    }
}