using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Entity.Infrastructure;
using EMIS.Entities.Log;
using EMIS.Utility.FormValidate;
using Bowin.Common.Data;
using System.Web;
using System.Data;
using System.Linq.Expressions;

namespace EMIS.Utility.Log
{
    public class DbLog
    {
        public static List<Log_Operate> GetBatchUpdateLog<T>(IList<T> entities, System.Data.Entity.DbContext ctx) where T : class
        {
            var result = new List<Log_Operate>();
            var principal = CustomPrincipal.Current;
            var operateUserID = (principal != null) ? (Guid?)principal.UserID : null;

            var tableKey = EMIS.Entities.TableKeyDictionary.GetKeyName<T>();
            ParameterExpression keyParamter = Expression.Parameter(typeof(DbEntityEntry<T>), "w");
            MemberExpression keyEntryExpression = Expression.Property(keyParamter, "Entity");
            MemberExpression keyExpression = Expression.Property(keyEntryExpression, tableKey);
            var entryList = ctx.ChangeTracker.Entries<T>().ToList();
            var originalValues = entities.Select(x => new {
                OriginalValues = entryList.FirstOrDefault(
                    Expression.Lambda<Func<DbEntityEntry<T>, bool>>(
                        Expression.Equal(keyExpression, Expression.Constant((Guid)typeof(T).GetProperty(tableKey).GetValue(x, null)))
                    , keyParamter).Compile()).OriginalValues,
                CurrentValues = x
            }).ToList();

            foreach (var updateChange in originalValues)
            {
                var log = new Log_Operate
                {
                    OperateID = Guid.NewGuid(),
                    UserID = operateUserID,
                    IP = ApplicationClientHelper.GetIP(),
                    TableName = updateChange.CurrentValues.GetType().Name,
                    SourceUrl = (HttpContext.Current == null) ? null : HttpContext.Current.Request.UrlReferrer.OriginalString,
                    OperateTime = DateTime.Now
                };
                log.Operate = "修改";
                log.Detail = "修改前内容（" + GatherValues(updateChange.OriginalValues) + "），";
                log.Detail += "修改后内容（" + GatherValues(updateChange.CurrentValues) + "）";

                result.Add(log);
            }

            return result;
        }

        public static List<Log_Operate> GetBulkInsertLog<T>(IList<T> entities)
        {
            var table = entities.ToTable();
            return GetBulkInsertLog(table, typeof(T).Name);
        }
        public static List<Log_Operate> GetBulkInsertLog(DataTable table, string tableName)
        {
            var result = new List<Log_Operate>();
            var principal = CustomPrincipal.Current;
            var operateUserID = (principal != null) ? (Guid?)principal.UserID : null;
            var myIP = ApplicationClientHelper.GetIP();

            foreach (DataRow row in table.Rows)
            {
                var value = "详细内容（";
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    string columnName = table.Columns[i].ColumnName;
                    value += columnName + ":";
                    value += row[columnName].ToString() + "|";
                }
                if (value.EndsWith("|"))
                {
                    value = value.TrimEnd('|');
                }
                value += "）";

                Log_Operate operate = new Log_Operate()
                {
                    OperateID = Guid.NewGuid(),
                    UserID = operateUserID,
                    IP = myIP,
                    TableName = tableName,
                    SourceUrl = (HttpContext.Current == null) ? null : HttpContext.Current.Request.UrlReferrer.OriginalString,
                    OperateTime = DateTime.Now,
                    Operate = "新增",
                    Detail = value
                };

                result.Add(operate);
            }

            return result;
        }

        public static List<Log_Operate> GetDeleteLog<T>(IList<T> entities)
        {
            var table = entities.ToTable();
            return GetDeleteLog(table, typeof(T).Name);
        }
        public static List<Log_Operate> GetDeleteLog(DataTable table, string tableName)
        {
            var result = new List<Log_Operate>();
            var principal = CustomPrincipal.Current;
            var operateUserID = (principal != null) ? (Guid?)principal.UserID : null;
            var myIP = ApplicationClientHelper.GetIP();

            foreach (DataRow row in table.Rows)
            {
                var value = "删除内容（";
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    string columnName = table.Columns[i].ColumnName;
                    value += columnName + ":";
                    value += row[columnName].ToString() + "|";
                }
                if (value.EndsWith("|"))
                {
                    value = value.TrimEnd('|');
                }
                value += "）";

                Log_Operate operate = new Log_Operate()
                {
                    OperateID = Guid.NewGuid(),
                    UserID = operateUserID,
                    IP = myIP,
                    TableName = tableName,
                    SourceUrl = (HttpContext.Current == null) ? null : HttpContext.Current.Request.UrlReferrer.OriginalString,
                    OperateTime = DateTime.Now,
                    Operate = "删除",
                    Detail = value
                };

                result.Add(operate);
            }

            return result;
        }

        public static List<Log_Operate> GetLog(DbChangeTracker changeTracker)
        {
            var result = new List<Log_Operate>();
            var entryList = changeTracker.Entries().ToList();
            var principal = CustomPrincipal.Current;

            entryList.ForEach(x => AddLog(x, result, principal));

            return result;
        }

        public static List<Log_Operate> GetRelationshipLog(System.Data.Entity.DbContext ctx)
        {
            var result = new List<Log_Operate>();
            var principal = CustomPrincipal.Current;
            var operateUserID = (principal != null) ? (Guid?)principal.UserID : null;
            var objectContext = ((IObjectContextAdapter)ctx).ObjectContext;
            var deleteChanges = objectContext.ObjectStateManager.GetObjectStateEntries(System.Data.Entity.EntityState.Deleted);
            var addChanges = objectContext.ObjectStateManager.GetObjectStateEntries(System.Data.Entity.EntityState.Added);
            var myIP = ApplicationClientHelper.GetIP();

            foreach(var deleteChange in deleteChanges)
            {
                if (deleteChange.IsRelationship)
                {
                    var log = new Log_Operate
                    {
                        OperateID = Guid.NewGuid(),
                        UserID = operateUserID,
                        IP = myIP,
                        TableName = deleteChange.EntitySet.Name,
                        SourceUrl = (HttpContext.Current == null) ? null : HttpContext.Current.Request.UrlReferrer.OriginalString,
                        OperateTime = DateTime.Now,
                        Operate = "删除",
                        Detail = "删除内容（" + GatherValues(deleteChange.OriginalValues) + "）"
                    };
                    result.Add(log);
                }
            }
            foreach (var addChange in addChanges)
            {
                if (addChange.IsRelationship)
                {
                    var log = new Log_Operate
                    {
                        OperateID = Guid.NewGuid(),
                        UserID = operateUserID,
                        IP = myIP,
                        TableName = addChange.EntitySet.Name,
                        SourceUrl = (HttpContext.Current == null) ? null : HttpContext.Current.Request.UrlReferrer.OriginalString,
                        OperateTime = DateTime.Now,
                        Operate = "新增",
                        Detail = "详细内容（" + GatherRelationValues(addChange.CurrentValues, objectContext) + "）"
                    };
                    result.Add(log);
                }
            }

            return result;
        }

        private static void AddLog(DbEntityEntry entry, IList<Log_Operate> logList, CustomPrincipal principal)
        {
            var operateUserID = (principal != null) ? (Guid?)principal.UserID : null;
            var log = new Log_Operate { 
                    OperateID = Guid.NewGuid(),
                    UserID = operateUserID,
                    IP = ApplicationClientHelper.GetIP(),
                    TableName = entry.Entity.GetType().Name,
                    SourceUrl = (HttpContext.Current == null) ? null : (HttpContext.Current.Request.UrlReferrer != null ? HttpContext.Current.Request.UrlReferrer.OriginalString : HttpContext.Current.Request.RawUrl),
                    OperateTime = DateTime.Now
                };
            switch (entry.State)
            {
                case System.Data.Entity.EntityState.Added:
                    log.Operate = "新增";
                    log.Detail = "详细内容（" + GatherValues(entry.CurrentValues) + "）";
                    break;
                case System.Data.Entity.EntityState.Modified:
                    log.Operate = "修改";
                    log.Detail = "修改前内容（" + GatherValues(entry.OriginalValues) + "），";
                    log.Detail += "修改后内容（" + GatherValues(entry.CurrentValues) + "）";
                    break;
                case System.Data.Entity.EntityState.Deleted:
                    log.Operate = "删除";
                    log.Detail = "删除内容（" + GatherValues(entry.OriginalValues) + "）";
                    break;
                default:
                    return;
            }

            logList.Add(log);
        }

        private static string GatherRelationValues(System.Data.Common.DbDataRecord values, 
            System.Data.Entity.Core.Objects.ObjectContext context)
        {
            var result = "";
            for (int i = 0; i < values.FieldCount; i ++ )
            {
                var entry = (System.Data.Entity.Core.EntityKey)values.GetValue(i);
                result += entry.EntitySetName + ":";
                var entity = context.GetObjectByKey(entry);
                var entityType = entity.GetType();
                var propertyName = entry.GetEntitySet(context.MetadataWorkspace).ElementType.KeyMembers[0].Name;
                var property = entityType.GetProperty(propertyName);
                result += property.GetValue(entity, null) + "|";
                //foreach (var property in entityType.GetProperties())
                //{
                //    result += property.Name + ":" + property.GetValue(entity, null) + "|";
                //}
            }
            if (result.EndsWith("|"))
            {
                result = result.TrimEnd('|');
            }

            return result;
        }

        private static string GatherValues(System.Data.Common.DbDataRecord values)
        {
            var result = "";
            for (int i = 0; i < values.FieldCount; i ++ )
            {
                var entry = (System.Data.Entity.Core.EntityKey)values.GetValue(i);
                result += entry.EntitySetName + ":" + entry.EntityKeyValues[0].Value.ToString() + "|";
            }
            if (result.EndsWith("|"))
            {
                result = result.TrimEnd('|');
            }

            return result;
        }

        private static string GatherValues(DbPropertyValues values)
        {
            var result = "";
            foreach (var propertyName in values.PropertyNames)
            {
                result += propertyName + ":" + values[propertyName] + "|";
            }
            if (result.EndsWith("|"))
            {
                result = result.TrimEnd('|');
            }

            return result;
        }

        private static string GatherValues<T>(T entity)
        {
            var result = "";
            var properties = typeof(T).GetProperties();
            foreach (var property in properties)
            {
                if (property.PropertyType.IsPrimitive || property.PropertyType.IsValueType || property.PropertyType.Name.StartsWith("String"))
                {
                    result += property.Name + ":" + (property.GetValue(entity, null) ?? "").ToString() + "|";
                }
            }
            if (result.EndsWith("|"))
            {
                result = result.TrimEnd('|');
            }

            return result;
        }
    }
}