using Microsoft.Practices.EnterpriseLibrary.Data;
using ProjectBase.Data.Logs;
using ProjectBase.Data.Pager;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Data.Common;
using Oracle.ManagedDataAccess.Client;
using System.Linq;
using System.Text;
using System.Threading.Tasks;


namespace ProjectBase.Data.BaseDAL.BaseDatabase
{
        /// <summary>
        /// 数据访问层的基类
        /// </summary>
        public abstract class BaseDALOracle<T> : AbstractBaseDAL<T>, IBaseDAL<T> where T : BaseEntity, new()
        {
            #region 构造函数

            private string seqField = "";//指定那个字段是用序列来控制它的值的，一般为主键
            private string seqName = "";//指定的序列名称，建议规则为：SEQ_表名称

            /// <summary>
            /// 指定那个字段是用序列来控制它的值的，一般为主键
            /// </summary>
            public string SeqField
            {
                get { return seqField; }
                set { seqField = value; }
            }

            /// <summary>
            /// 指定的序列名称，建议规则为：SEQ_表名称
            /// </summary>
            public string SeqName
            {
                get { return seqName; }
                set { seqName = value; }
            }

            /// <summary>
            /// 默认构造函数
            /// </summary>
            public BaseDALOracle()
            { }

            /// <summary>
            /// 指定表名以及主键,对基类进构造
            /// </summary>
            /// <param name="tableName">表名</param>
            /// <param name="primaryKey">表主键</param>
            public BaseDALOracle(string tableName, string primaryKey)
                : base(tableName, primaryKey)
            {
                this.parameterPrefix = ":";   //数据库参数化访问的占位符
                this.safeFieldFormat = "{0}"; //防止和保留字、关键字同名的字段格式(尽量避免）

                //设置表的自增长序列字段，及序列名称 
                this.seqField = primaryKey;
                this.seqName = string.Format("SEQ_{0}", tableName);
            }

            #endregion

            #region 通用操作方法

            /// <summary>
            /// 添加记录
            /// </summary>
            /// <param name="recordField">Hashtable:键[key]为字段名;值[value]为字段对应的值</param>
            /// <param name="targetTable">需要操作的目标表名称</param>
            /// <param name="trans">事务对象,如果使用事务,传入事务对象,否则为Null不使用事务</param>
            public override bool Insert(Hashtable recordField, string targetTable, DbTransaction trans)
            {
                bool result = false;
                if (recordField == null || recordField.Count < 1)
                {
                    return result;
                }

                string fields = ""; // 字段名
                string vals = ""; // 字段值
                foreach (string field in recordField.Keys)
                {
                    fields += field + ",";

                    if (!string.IsNullOrEmpty(seqField) && !string.IsNullOrEmpty(seqName)
                        && (field.ToUpper() == seqField.ToUpper()))
                    {
                        vals += string.Format("{0}.NextVal,", seqName);
                    }
                    else
                    {
                        vals += string.Format("{0}{1},", parameterPrefix, field);
                    }
                }
                fields = fields.Trim(',');//除去前后的逗号
                vals = vals.Trim(',');//除去前后的逗号
                string sql = string.Format("INSERT INTO {0} ({1}) VALUES ({2})", targetTable, fields, vals);
                //LogTextHelper.Info(sql);

                Database db = CreateDatabase();
                DbCommand command = db.GetSqlStringCommand(sql);

                foreach (string field in recordField.Keys)
                {
                    if (!string.IsNullOrEmpty(seqField) && !string.IsNullOrEmpty(seqName)
                        && (field.ToUpper() == seqField.ToUpper()))
                    {
                    }
                    else
                    {
                        object val = recordField[field];
                        val = val ?? DBNull.Value;
                        if (val is DateTime)
                        {
                            if (Convert.ToDateTime(val) <= Convert.ToDateTime("1753-1-1"))
                            {
                                val = DBNull.Value;
                            }
                            db.AddInParameter(command, field, DbType.DateTime, val);
                        }
                        else
                        {
                            if (val.ToString().Length >= 2000)
                            {
                                AddInClobParameter(command, field, val.ToString());
                            }
                            else
                            {
                                db.AddInParameter(command, field, TypeToDbType(val.GetType()), val);
                            }
                        }
                    }
                }

                if (trans != null)
                {
                    result = db.ExecuteNonQuery(command, trans) > 0;
                }
                else
                {
                    result = db.ExecuteNonQuery(command) > 0;
                }

                return result;
            }

            /// <summary>
            /// 添加记录
            /// </summary>
            /// <param name="recordField">Hashtable:键[key]为字段名;值[value]为字段对应的值</param>
            /// <param name="targetTable">需要操作的目标表名称</param>
            /// <param name="trans">事务对象,如果使用事务,传入事务对象,否则为Null不使用事务</param>
            public override int Insert2(Hashtable recordField, string targetTable, DbTransaction trans)
            {
                int result = -1;
                if (recordField == null || recordField.Count < 1)
                {
                    return result;
                }

                string fields = ""; // 字段名
                string vals = ""; // 字段值
                foreach (string field in recordField.Keys)
                {
                    fields += field + ",";

                    if (!string.IsNullOrEmpty(seqField) && !string.IsNullOrEmpty(seqName)
                        && (field.ToUpper() == seqField.ToUpper()))
                    {
                        vals += string.Format("{0}.NextVal,", seqName);
                    }
                    else
                    {
                        vals += string.Format("{0}{1},", parameterPrefix, field);
                    }
                }
                fields = fields.Trim(',');//除去前后的逗号
                vals = vals.Trim(',');//除去前后的逗号
                string sql = string.Format("INSERT INTO {0} ({1}) VALUES ({2})", targetTable, fields, vals);

                Database db = CreateDatabase();
                DbCommand command = db.GetSqlStringCommand(sql);

                foreach (string field in recordField.Keys)
                {
                    if (!string.IsNullOrEmpty(seqField) && !string.IsNullOrEmpty(seqName)
                        && (field.ToUpper() == seqField.ToUpper()))
                    {
                    }
                    else
                    {
                        object val = recordField[field];
                        val = val ?? DBNull.Value;
                        if (val is DateTime)
                        {
                            if (Convert.ToDateTime(val) <= Convert.ToDateTime("1753-1-1"))
                            {
                                val = DBNull.Value;
                            }
                            db.AddInParameter(command, field, DbType.DateTime, val);
                        }
                        else
                        {
                            if (val.ToString().Length >= 2000)
                            {
                                AddInClobParameter(command, field, val.ToString());
                            }
                            else
                            {
                                db.AddInParameter(command, field, TypeToDbType(val.GetType()), val);
                            }
                        }
                    }
                }

                if (trans != null)
                {
                    db.ExecuteNonQuery(command, trans);

                    sql = string.Format("SELECT {0}.Currval ID From Dual", seqName);
                    command = db.GetSqlStringCommand(sql);
                    result = Convert.ToInt32(db.ExecuteScalar(command, trans).ToString());
                }
                else
                {
                    db.ExecuteNonQuery(command);

                    sql = string.Format("SELECT {0}.Currval ID From Dual", seqName);
                    command = db.GetSqlStringCommand(sql);
                    result = Convert.ToInt32(db.ExecuteScalar(command).ToString());
                }

                return result;
            }

            /// <summary>
            /// 为指定查询对象增加一个clob类型参数并赋值
            /// </summary>
            /// <param name="command">查询对象</param>
            /// <param name="paranme">参数名</param>
            /// <param name="data">参数值</param>
            public static void AddInClobParameter(DbCommand command, string paranme, string data)
            {
                OracleParameter p = new OracleParameter(paranme, System.Data.OracleClient.OracleType.Clob);
                p.Direction = ParameterDirection.Input;
                p.Value = data;
                command.Parameters.Add(p);
            }

            /// <summary>
            /// 测试数据库是否正常连接
            /// </summary>
            public override bool TestConnection(string connectionString)
            {
                bool result = false;

                using (DbConnection connection = new OracleConnection(connectionString))
                {
                    connection.Open();
                    if (connection.State == System.Data.ConnectionState.Open)
                    {
                        result = true;
                    }
                }

                return result;
            }

            #endregion

            #region 对象添加、修改、查询接口

            /// <summary>
            /// 查找记录表中最旧的一条记录
            /// </summary>
            /// <param name="trans">事务对象</param>
            /// <returns></returns>
            public override T FindFirst(DbTransaction trans = null)
            {
                string sql = string.Format(@"Select * from (Select {0} From {1} Order by {2} ASC) 
                                         WHERE ROWNUM <= 1 ORDER BY ROWNUM ASC", selectedFields, tableName, GetSafeFileName(sortField));

                Database db = CreateDatabase();
                DbCommand command = db.GetSqlStringCommand(sql);

                T entity = GetEntity(db, command, trans);
                return entity;
            }

            /// <summary>
            /// 查找记录表中最新的一条记录
            /// </summary>
            /// <param name="trans">事务对象</param>
            /// <returns></returns>
            public override T FindLast(DbTransaction trans = null)
            {
                string sql = string.Format(@"Select * from (Select {0} From {1} Order by {2} DESC)
                                         WHERE ROWNUM <= 1 ORDER BY ROWNUM ASC", selectedFields, tableName, GetSafeFileName(sortField));

                Database db = CreateDatabase();
                DbCommand command = db.GetSqlStringCommand(sql);

                T entity = GetEntity(db, command, trans);
                return entity;
            }

            #region 下面两个覆盖基类函数，指定具体的数据库类型
            /// <summary>
            /// 根据条件查询数据库,并返回对象集合(用于分页数据显示)
            /// </summary>
            /// <param name="condition">查询的条件</param>
            /// <param name="info">分页实体</param>
            /// <param name="fieldToSort">排序字段</param>
            /// <param name="desc">是否降序</param>
            /// <param name="trans">事务对象</param>
            /// <returns>指定对象的集合</returns>
            public override List<T> FindWithPager(string condition, PagerInfo info, string fieldToSort, bool desc, DbTransaction trans = null)
            {
                if (HasInjectionData(condition))
                {
                    LogHelper.log.Error(string.Format("检测出SQL注入的恶意数据, {0}", condition));
                    throw new Exception("检测出SQL注入的恶意数据");
                }


                PagerHelper helper = new PagerHelper(tableName, this.selectedFields, fieldToSort,
                    info.PageSize, info.CurrenetPageIndex, desc, condition);

                string countSql = helper.GetPagingSql(DatabaseType.Oracle, true);
                string strCount = SqlValueList(countSql, trans);
                info.RecordCount = Convert.ToInt32(strCount);

                string dataSql = helper.GetPagingSql(DatabaseType.Oracle, false);
                List<T> list = GetList(dataSql, null, trans);
                return list;
            }

            /// <summary>
            /// 根据条件查询数据库,并返回DataTable集合(用于分页数据显示)
            /// </summary>
            /// <param name="condition">查询的条件</param>
            /// <param name="info">分页实体</param>
            /// <param name="fieldToSort">排序字段</param>
            /// <param name="desc">是否降序</param>
            /// <param name="trans">事务对象</param>
            /// <returns>指定DataTable的集合</returns>
            public override DataTable FindToDataTable(string condition, PagerInfo info, string fieldToSort, bool desc, DbTransaction trans = null)
            {
                if (HasInjectionData(condition))
                {
                    LogHelper.log.Error(string.Format("检测出SQL注入的恶意数据, {0}", condition));
                    throw new Exception("检测出SQL注入的恶意数据");
                }

                PagerHelper helper = new PagerHelper(tableName, this.selectedFields, fieldToSort,
                    info.PageSize, info.CurrenetPageIndex, desc, condition);

                string countSql = helper.GetPagingSql(DatabaseType.Oracle, true);
                string strCount = SqlValueList(countSql, trans);
                info.RecordCount = Convert.ToInt32(strCount);

                string dataSql = helper.GetPagingSql(DatabaseType.Oracle, false);
                return GetDataTableBySql(dataSql, trans);
            }

            #endregion

            /// <summary>
            /// 获取前面记录指定数量的记录
            /// </summary>
            /// <param name="sql">查询语句</param>
            /// <param name="count">指定数量</param>
            /// <param name="orderBy">排序条件，例如order by id</param>
            /// <param name="trans">事务对象</param>
            /// <returns></returns>
            public override DataTable GetTopResult(string sql, int count, string orderBy, DbTransaction trans = null)
            {
                string resultSql = string.Format("select * from ({1} {2}) where rownum <={0} ", count, sql, orderBy);
                return SqlTable(resultSql, trans);
            }

            /// <summary>
            /// 获取数据库的全部表名称
            /// </summary>
            /// <returns></returns>
            public override List<string> GetTableNames()
            {
                string sql = string.Format("SELECT table_name FROM user_tables");
                Database db = CreateDatabase();
                DbCommand command = db.GetSqlStringCommand(sql);

                List<string> list = new List<string>();
                using (IDataReader dr = db.ExecuteReader(command))
                {
                    while (dr.Read())
                    {
                        list.Add(dr[0].ToString());
                    }
                }
                return list;
            }

            #endregion
        }
    }