using System;
using System.Data;
using System.Linq;
using System.Reflection;
using System.Web;

namespace GSYWApi
{
    /// <summary>
    /// 通用方法帮助类
    /// </summary>
    public class CommonHelper
    {
        #region 方法 -> 将DateTime类型转换为long类型
        /// <summary>
        /// 将DateTime类型转换为long类型
        /// </summary>
        /// <param name="dt">时间</param>
        /// <returns></returns>
        public static long ConvertDataTimeLong(DateTime dt)
        {
            DateTime dtStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
            TimeSpan toNow = dt.Subtract(dtStart);
            long timeStamp = toNow.Ticks;
            timeStamp = long.Parse(timeStamp.ToString().Substring(0, timeStamp.ToString().Length - 7));
            return timeStamp;
        }
        #endregion

        #region 方法 -> 将Long类型转换为DateTime类型
        /// <summary>
        /// 将Long类型转换为DateTime类型
        /// </summary>
        /// <param name="d">long</param>
        /// <returns></returns>s
        public static DateTime ConvertLongDateTime(long d)
        {
            DateTime dtStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
            long lTime = long.Parse(d + "0000000");
            TimeSpan toNow = new TimeSpan(lTime);
            DateTime dtResult = dtStart.Add(toNow);
            return dtResult;
        }

        /// <summary>
        /// 时间戳(毫秒值)String转换为DateTime类型转换
        /// </summary>
        /// <param name="time">毫秒时间戳</param>
        /// <returns></returns>
        public static DateTime TicksToDate(string time)
        {
            return new DateTime((Convert.ToInt64(time) * 10000) + 621355968000000000);
        }
        #endregion

        #region 方法 -> 枚举参数过滤处理
        /// <summary>
        /// 枚举参数过滤处理，解决麻烦的SQL拼接
        /// （对照数据表给定添加、更新的参数枚举类型ValueType）
        /// </summary>
        /// <param name="_Type">数据类型</param>
        /// <param name="_String">数据值</param>
        /// <returns></returns>
        public static string IsArrayType(ValueType _Type, object _String = null)
        {
            if (_String != null && _String.ToString() != "")
            {
                switch (_Type)
                {
                    case ValueType.String:
                        return string.Format("'{0}'", _String.ToString().Replace("'", " "));
                    case ValueType.Int:
                    case ValueType.Double:
                    case ValueType.Boolean:
                        return _String.ToString();
                    case ValueType.DateTime:
                        return string.Format("TO_DATE('{0}','YYYY/MM/DD HH24:MI:SS')", _String);
                }
            }
            return "null";
        }

        /// <summary>
        /// 枚举参数过滤处理，解决麻烦的SQL拼接
        /// （对照数据表给定添加、更新的参数枚举类型ValueType）
        /// </summary>
        /// <param name="_Type">数据类型</param>
        /// <param name="_DefaultValue">是否使用缺省值</param>
        /// <returns></returns>
        private static string IsArrayType(ValueType _Type, bool _DefaultValue = false)
        {
            if (_DefaultValue)
            {
                switch (_Type)
                {
                    case ValueType.String:
                        return "''";
                    case ValueType.Int:
                    case ValueType.Double:
                    case ValueType.Boolean:
                        return "0";
                    case ValueType.DateTime:
                        return string.Format("TO_DATE('{0}','YYYY/MM/DD HH24:MI:SS')", DateTime.Now.ToString());
                }
            }
            return "null";
        }
        #endregion

        #region 方法 -> 定义5个类型的枚举
        /// <summary>
        /// 定义5个类型的枚举
        /// </summary>
        public enum ValueType
        {
            /// <summary>
            /// 字符串
            /// </summary>
            String = 0,
            /// <summary>
            /// 整型
            /// </summary>
            Int = 1,
            /// <summary>
            /// 双精度
            /// </summary>
            Double = 2,
            /// <summary>
            /// true或false
            /// </summary>
            Boolean = 3,
            /// <summary>
            /// 日期
            /// </summary>
            DateTime = 4
        }
        #endregion

        #region 方法 -> SQL语句分页
        /// <summary>
        /// SQL语句分页
        /// </summary>
        /// <param name="sql">SQL语句</param>
        /// <param name="rn">开始的行号</param>
        /// <param name="rowNum">结束的行号</param>
        /// <returns></returns>
        public static string GetPageSql(string sql, int? rn = null, int? rowNum = null)
        {
            if (rn != null && rowNum != null)
            {
                //分页查询
                sql = string.Format(@"
                    SELECT * FROM (
                        SELECT ROWNUM RN,N.* FROM ({0}) N   WHERE ROWNUM<={1} 
                    ) M WHERE M.RN>={2}", sql, rowNum, rn);
            }

            return sql;
        }
        #endregion

        #region 方法 -> 为属性赋值
        /// <summary>
        /// 为属性赋值
        /// </summary>
        /// <typeparam name="T">源单类</typeparam>
        /// <typeparam name="S">需要转换的实体类</typeparam>
        /// <param name="source"></param>
        /// <returns></returns>
        public static S EntityConvert<T, S>(T source)
        {
            S target = Activator.CreateInstance<S>();
            var sType = source.GetType();
            var dType = typeof(S);
            foreach (PropertyInfo now in sType.GetProperties())
            {
                var name = dType.GetProperty(now.Name);
                if (name == null)
                    continue;
                dType.GetProperty(now.Name).SetValue(target, now.GetValue(source));
            }
            return target;
        }
        #endregion

        #region 方法 -> 获取指定页码Datatable数据
        /// <summary>
        /// 获取指定页码Datatable数据
        /// </summary>
        /// <param name="dtOrigin">源数据</param>
        /// <param name="pageSize">返回第几页数据</param>
        /// <param name="pageIndex">每页返回的数量</param>
        /// <returns>Datatable数据格式</returns>
        public static DataTable GetDataTableWithPageSize(DataTable dtOrigin, int pageSize, int pageIndex)
        {
            if (pageSize == 0)
            {
                pageSize = 10;
            }
            if (pageIndex == 0)
            {
                pageIndex = 1;
            }
            //克隆数据源
            DataTable dtClone = dtOrigin.Clone();
            dtClone.Columns.Add("RN", typeof(int));
            //开始插入数据源
            for (int RowCount = 0; RowCount < pageSize; RowCount++)
            {
                //获取当前数据源行数
                int RN = pageSize * (pageIndex - 1) + RowCount;
                //如果行数大于数据源实际数量，则直接跳过
                if (RN >= dtOrigin.Rows.Count)
                {
                    break;
                }
                //获取当前数据源内容
                DataRow EndAccountDataRow = dtOrigin.Rows[RN];
                //创建一个新 System.Data.DataRow 具有与表相同的架构
                DataRow _DataRow = dtClone.NewRow();
                //开始插入数据
                for (int ColumnsCount = 0; ColumnsCount < dtOrigin.Columns.Count; ColumnsCount++)
                {
                    _DataRow[ColumnsCount] = EndAccountDataRow[ColumnsCount];
                }
                _DataRow["RN"] = RN + 1;
                //将数据加入到克隆的DataTable中
                dtClone.Rows.Add(_DataRow);
            }

            return dtClone;
        }
        #endregion
    }
}