using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;

namespace SqlSugar
{
    public class MethodCallExpressionResolve : BaseResolve
    {
        public MethodCallExpressionResolve(ExpressionParameter parameter) : base(parameter)
        {
            var express = base.Expression as MethodCallExpression;
            var isLeft = parameter.IsLeft;
            var methodName = express.Method.Name;
            var isValidNativeMethod = IsValidNativeMethod(express, methodName);
            List<MethodCallExpressionArgs> appendArgs = null;
            if (MethodTimeMapping.ContainsKey(methodName))
            {
                appendArgs = new List<MethodCallExpressionArgs>();
                var dateType = MethodTimeMapping[methodName];
                var paramterName = this.Context.SqlParameterKeyWord + ExpressionConst.Const + this.Context.ParameterIndex;
                appendArgs.Add(new MethodCallExpressionArgs { IsMember = false, MemberName = paramterName, MemberValue = dateType });
                this.Context.Parameters.Add(new SugarParameter(paramterName, dateType.ToString()));
                this.Context.ParameterIndex++;
                methodName = "DateAdd";
                isValidNativeMethod = true;
            }
            else if (methodName == "get_Item")
            {
                var paramterName = this.Context.SqlParameterKeyWord + ExpressionConst.Const + this.Context.ParameterIndex;
                this.Context.Parameters.Add(new SugarParameter(paramterName, ExpressionTool.DynamicInvoke(express)));
                this.Context.Result.Append(string.Format(" {0} ", paramterName));
                this.Context.ParameterIndex++;
                return;
            }
            else if (methodName == "NewGuid")
            {
                this.Context.Result.Append(this.Context.DbMehtods.GuidNew());
                return;
            }
            else if (IsSubMethod(express, methodName))
            {
                //Check.Exception(!(parameter.BaseExpression is BinaryExpression), "Current expressions are not supported");
                var subResolve = new SubResolve(express, this.Context, parameter.OppsiteExpression);
                var appendSql = subResolve.GetSql();
                if (this.Context.ResolveType.IsIn(ResolveExpressType.SelectMultiple, ResolveExpressType.SelectSingle) || (parameter.BaseParameter != null && parameter.BaseParameter.CommonTempData != null && parameter.BaseParameter.CommonTempData.Equals(CommonTempDataType.Result)))
                {
                    parameter.BaseParameter.CommonTempData = appendSql;
                }
                else
                {
                    base.AppendValue(parameter, isLeft, appendSql);
                }
                return;
            }
            else if (IsIfElse(express, methodName))
            {
                var caseResole = new CaseWhenResolve(express, this.Context, parameter.OppsiteExpression);
                var appendSql = caseResole.GetSql();
                if (this.Context.ResolveType.IsIn(ResolveExpressType.SelectMultiple, ResolveExpressType.SelectSingle))
                {
                    parameter.BaseParameter.CommonTempData = appendSql;
                }
                else
                {
                    base.AppendValue(parameter, isLeft, appendSql);
                }
                return;
            }
            if (IsContainsArray(express, methodName, isValidNativeMethod))
            {
                methodName = "ContainsArray";
                isValidNativeMethod = true;
            }
            if (isValidNativeMethod)
            {
                NativeExtensionMethod(parameter, express, isLeft, MethodMapping[methodName], appendArgs);
            }
            else
            {
                SqlFuncMethod(parameter, express, isLeft);
            }
        }

        private bool IsValidNativeMethod(MethodCallExpression express, string methodName)
        {
            return MethodMapping.ContainsKey(methodName) && express.Method.DeclaringType.Namespace == ("System");
        }

        private bool IsExtMethod(string methodName)
        {
            if (this.Context.SqlFuncServices == null) return false;
            return this.Context.SqlFuncServices.Select(it => it.UniqueMethodName).Contains(methodName);
        }

        private bool IsIfElse(MethodCallExpression express, string methodName)
        {
            if (methodName == "End" && express.Object.Type == typeof(CaseWhen))
                return true;
            else
                return false;
        }

        private void SqlFuncMethod(ExpressionParameter parameter, MethodCallExpression express, bool? isLeft)
        {
            if (!CheckMethod(express))
            {
                CusMethod(parameter, express, isLeft);
            }
            else
            {
                var method = express.Method;
                var name = method.Name;
                var args = express.Arguments.Cast<Expression>().ToList();
                var model = new MethodCallExpressionModel
                {
                    Args = new List<MethodCallExpressionArgs>()
                };
                switch (this.Context.ResolveType)
                {
                    case ResolveExpressType.WhereSingle:
                    case ResolveExpressType.WhereMultiple:
                        Check.Exception(name == "GetSelfAndAutoFill", "SqlFunc.GetSelfAndAutoFill can only be used in Select.");
                        Where(parameter, isLeft, name, args, model);
                        break;

                    case ResolveExpressType.SelectSingle:
                    case ResolveExpressType.SelectMultiple:
                    case ResolveExpressType.Update:
                        Select(parameter, isLeft, name, args, model);
                        break;

                    case ResolveExpressType.FieldSingle:
                    case ResolveExpressType.FieldMultiple:
                        Field(parameter, isLeft, name, args, model);
                        break;

                    default:
                        break;
                }
            }
        }

        private void CusMethod(ExpressionParameter parameter, MethodCallExpression express, bool? isLeft)
        {
            try
            {
                var constValue = ExpressionTool.DynamicInvoke(express);
                parameter.BaseParameter.CommonTempData = constValue;
                var parameterName = base.AppendParameter(constValue);
                if (parameter.BaseParameter.CommonTempData != null && parameter.BaseParameter.CommonTempData.Equals(CommonTempDataType.Result))
                {
                    this.Context.Result.Append(parameterName);
                }
                else
                {
                    base.AppendValue(parameter, isLeft, parameterName);
                }
            }
            catch
            {
                Check.Exception(true, string.Format(ErrorMessage.MethodError, express.Method.Name));
            }
        }

        private void NativeExtensionMethod(ExpressionParameter parameter, MethodCallExpression express, bool? isLeft, string name, List<MethodCallExpressionArgs> appendArgs = null)
        {
            var method = express.Method;
            var args = express.Arguments.Cast<Expression>().ToList();
            var model = new MethodCallExpressionModel
            {
                Args = new List<MethodCallExpressionArgs>()
            };
            switch (this.Context.ResolveType)
            {
                case ResolveExpressType.WhereSingle:
                case ResolveExpressType.WhereMultiple:
                    if (express.Object != null)
                        args.Insert(0, express.Object);
                    Where(parameter, isLeft, name, args, model, appendArgs);
                    break;

                case ResolveExpressType.SelectSingle:
                case ResolveExpressType.SelectMultiple:
                case ResolveExpressType.Update:
                    if (express.Object != null)
                        args.Insert(0, express.Object);
                    Select(parameter, isLeft, name, args, model, appendArgs);
                    break;

                case ResolveExpressType.FieldSingle:
                case ResolveExpressType.FieldMultiple:
                default:
                    break;
            }
        }

        private void Field(ExpressionParameter parameter, bool? isLeft, string name, IEnumerable<Expression> args, MethodCallExpressionModel model, List<MethodCallExpressionArgs> appendArgs = null)
        {
            if (this.Context.ResolveType == ResolveExpressType.FieldSingle)
            {
                this.Context.ResolveType = ResolveExpressType.WhereSingle;
            }
            else
            {
                this.Context.ResolveType = ResolveExpressType.WhereMultiple;
            }
            Where(parameter, isLeft, name, args, model);
        }

        private void Select(ExpressionParameter parameter, bool? isLeft, string name, IEnumerable<Expression> args, MethodCallExpressionModel model, List<MethodCallExpressionArgs> appendArgs = null)
        {
            if (name == "GetSelfAndAutoFill")
            {
                var memberValue = (args.First() as MemberExpression).Expression.ToString();
                model.Args.Add(new MethodCallExpressionArgs { MemberValue = memberValue, IsMember = true, MemberName = memberValue });
            }
            else
            {
                foreach (var item in args)
                {
                    AppendItem(parameter, name, args, model, item);
                }
                if (appendArgs != null)
                {
                    model.Args.AddRange(appendArgs);
                }
            }
            if (parameter.BaseParameter.BaseParameter.BaseParameter == null)
            {
                this.Context.Result.Append(GetMdthodValue(name, model));
            }
            else
            {
                parameter.BaseParameter.CommonTempData = GetMdthodValue(name, model);
            }
        }

        private void Where(ExpressionParameter parameter, bool? isLeft, string name, IEnumerable<Expression> args, MethodCallExpressionModel model, List<MethodCallExpressionArgs> appendArgs = null)
        {
            foreach (var item in args)
            {
                var expItem = item;
                if (item is UnaryExpression)
                {
                    expItem = (item as UnaryExpression).Operand;
                }
                AppendItem(parameter, name, args, model, expItem);
            }
            if (appendArgs != null)
            {
                model.Args.AddRange(appendArgs);
            }
            var methodValue = GetMdthodValue(name, model);
            if (parameter.BaseExpression is BinaryExpression && parameter.OppsiteExpression.Type == UtilConstants.BoolType && name == "HasValue" && !(parameter.OppsiteExpression is BinaryExpression))
            {
                methodValue = this.Context.DbMehtods.CaseWhen(new List<KeyValuePair<string, string>> {
                    new KeyValuePair<string, string>("IF",methodValue.ObjToString()),
                    new KeyValuePair<string, string>("Return","1"),
                    new KeyValuePair<string, string>("End","0")
                 });
            }
            base.AppendValue(parameter, isLeft, methodValue);
        }

        private void AppendItem(ExpressionParameter parameter, string name, IEnumerable<Expression> args, MethodCallExpressionModel model, Expression item)
        {
            var isBinaryExpression = item is BinaryExpression || item is MethodCallExpression;
            var isConst = item is ConstantExpression;
            var isIIF = name == "IIF";
            var isIFFBoolMember = isIIF && (item is MemberExpression) && (item as MemberExpression).Type == UtilConstants.BoolType;
            var isIFFUnary = isIIF && (item is UnaryExpression) && (item as UnaryExpression).Operand.Type == UtilConstants.BoolType;
            var isIFFBoolBinary = isIIF && (item is BinaryExpression) && (item as BinaryExpression).Type == UtilConstants.BoolType;
            var isIFFBoolMethod = isIIF && (item is MethodCallExpression) && (item as MethodCallExpression).Type == UtilConstants.BoolType;
            var isFirst = item == args.First();
            if (isFirst && isIIF && isConst)
            {
                var value = (item as ConstantExpression).Value.ObjToBool() ? this.Context.DbMehtods.True() : this.Context.DbMehtods.False();
                var methodCallExpressionArgs = new MethodCallExpressionArgs
                {
                    IsMember = true,
                    MemberName = value,
                    MemberValue = value
                };
                model.Args.Add(methodCallExpressionArgs);
            }
            else if (isIFFUnary && !isFirst)
            {
                AppendModelByIIFMember(parameter, model, (item as UnaryExpression).Operand);
            }
            else if (isIFFBoolMember && !isFirst)
            {
                AppendModelByIIFMember(parameter, model, item);
            }
            else if (isIFFBoolBinary && !isFirst)
            {
                AppendModelByIIFBinary(parameter, model, item);
            }
            else if (isIFFBoolMethod && !isFirst)
            {
                AppendModelByIIFMethod(parameter, model, item);
            }
            else if (isBinaryExpression)
            {
                model.Args.Add(GetMethodCallArgs(parameter, item));
            }
            else
            {
                AppendModel(parameter, model, item);
            }
        }

        private void AppendModelByIIFMember(ExpressionParameter parameter, MethodCallExpressionModel model, Expression item)
        {
            parameter.CommonTempData = CommonTempDataType.Result;
            base.Expression = item;
            base.Start();
            var methodCallExpressionArgs = new MethodCallExpressionArgs
            {
                IsMember = parameter.ChildExpression is MemberExpression,
                MemberName = parameter.CommonTempData
            };
            if (methodCallExpressionArgs.IsMember && parameter.ChildExpression != null && parameter.ChildExpression.ToString() == "DateTime.Now")
            {
                methodCallExpressionArgs.IsMember = false;
            }
            var value = methodCallExpressionArgs.MemberName;
            if (methodCallExpressionArgs.IsMember)
            {
                var childExpression = parameter.ChildExpression as MemberExpression;
                if (childExpression.Expression != null && childExpression.Expression is ConstantExpression)
                {
                    methodCallExpressionArgs.IsMember = false;
                }
            }
            if (!methodCallExpressionArgs.IsMember)
            {
                var parameterName = this.Context.SqlParameterKeyWord + ExpressionConst.MethodConst + this.Context.ParameterIndex;
                this.Context.ParameterIndex++;
                methodCallExpressionArgs.MemberName = parameterName;
                methodCallExpressionArgs.MemberValue = value;
                this.Context.Parameters.Add(new SugarParameter(parameterName, value));
            }
            model.Args.Add(methodCallExpressionArgs);
            parameter.ChildExpression = null;
        }

        private void AppendModelByIIFBinary(ExpressionParameter parameter, MethodCallExpressionModel model, Expression item)
        {
            Check.Exception(true, "The SqlFunc.IIF(arg1,arg2,arg3) , {0} argument  do not support ", item.ToString());
        }

        private void AppendModelByIIFMethod(ExpressionParameter parameter, MethodCallExpressionModel model, Expression item)
        {
            var methodExpression = item as MethodCallExpression;
            if (methodExpression.Method.Name.IsIn("ToBool", "ToBoolean", "IIF"))
            {
                model.Args.Add(base.GetMethodCallArgs(parameter, item));
            }
            else
            {
                Check.Exception(true, "The SqlFunc.IIF(arg1,arg2,arg3) , {0} argument  do not support ", item.ToString());
            }
        }

        private void AppendModel(ExpressionParameter parameter, MethodCallExpressionModel model, Expression item)
        {
            parameter.CommonTempData = CommonTempDataType.Result;
            base.Expression = item;
            base.Start();
            var methodCallExpressionArgs = new MethodCallExpressionArgs
            {
                IsMember = parameter.ChildExpression is MemberExpression && !ExpressionTool.IsConstExpression(parameter.ChildExpression as MemberExpression),
                MemberName = parameter.CommonTempData
            };
            if (methodCallExpressionArgs.IsMember && parameter.ChildExpression != null && parameter.ChildExpression.ToString() == "DateTime.Now")
            {
                methodCallExpressionArgs.IsMember = false;
            }
            var value = methodCallExpressionArgs.MemberName;
            if (methodCallExpressionArgs.IsMember)
            {
                var childExpression = parameter.ChildExpression as MemberExpression;
                if (childExpression.Expression != null && childExpression.Expression is ConstantExpression)
                {
                    methodCallExpressionArgs.IsMember = false;
                }
            }
            if (!methodCallExpressionArgs.IsMember)
            {
                var parameterName = this.Context.SqlParameterKeyWord + ExpressionConst.MethodConst + this.Context.ParameterIndex;
                this.Context.ParameterIndex++;
                methodCallExpressionArgs.MemberName = parameterName;
                methodCallExpressionArgs.MemberValue = value;
                this.Context.Parameters.Add(new SugarParameter(parameterName, value));
            }
            model.Args.Add(methodCallExpressionArgs);
            parameter.ChildExpression = null;
        }

        private object GetMdthodValue(string name, MethodCallExpressionModel model)
        {
            if (IsExtMethod(name))
            {
                var type = DbType.SqlServer;
                if (this.Context is SqlServerExpressionContext)
                    type = DbType.SqlServer;
                else if (this.Context is MySqlExpressionContext)
                    type = DbType.MySql;
                else if (this.Context is SqliteExpressionContext)
                    type = DbType.Sqlite;
                else if (this.Context is OracleExpressionContext)
                    type = DbType.Oracle;
                return this.Context.SqlFuncServices.First(it => it.UniqueMethodName == name).MethodValue(model, type, this.Context);
            }
            else
            {
                switch (name)
                {
                    case "IIF":
                        return this.Context.DbMehtods.IIF(model);

                    case "HasNumber":
                        return this.Context.DbMehtods.HasNumber(model);

                    case "HasValue":
                        return this.Context.DbMehtods.HasValue(model);

                    case "IsNullOrEmpty":
                        return this.Context.DbMehtods.IsNullOrEmpty(model);

                    case "ToLower":
                        return this.Context.DbMehtods.ToLower(model);

                    case "ToUpper":
                        return this.Context.DbMehtods.ToUpper(model);

                    case "Trim":
                        return this.Context.DbMehtods.Trim(model);

                    case "Contains":
                        return this.Context.DbMehtods.Contains(model);

                    case "ContainsArray":
                        var caResult = this.Context.DbMehtods.ContainsArray(model);
                        this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[0].MemberName.ObjToString());
                        return caResult;

                    case "Equals":
                        return this.Context.DbMehtods.Equals(model);

                    case "DateIsSame":
                        if (model.Args.Count == 2)
                            return this.Context.DbMehtods.DateIsSameDay(model);
                        else
                        {
                            var dsResult = this.Context.DbMehtods.DateIsSameByType(model);
                            this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[2].MemberName.ObjToString());
                            return dsResult;
                        }
                    case "DateAdd":
                        if (model.Args.Count == 2)
                            return this.Context.DbMehtods.DateAddDay(model);
                        else
                        {
                            var daResult = this.Context.DbMehtods.DateAddByType(model);
                            this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[2].MemberName.ObjToString());
                            return daResult;
                        }
                    case "DateValue":
                        var dvResult = this.Context.DbMehtods.DateValue(model);
                        this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[1].MemberName.ObjToString());
                        return dvResult;

                    case "Between":
                        return this.Context.DbMehtods.Between(model);

                    case "StartsWith":
                        return this.Context.DbMehtods.StartsWith(model);

                    case "EndsWith":
                        return this.Context.DbMehtods.EndsWith(model);

                    case "ToInt32":
                        return this.Context.DbMehtods.ToInt32(model);

                    case "ToInt64":
                        return this.Context.DbMehtods.ToInt64(model);

                    case "ToDate":
                        return this.Context.DbMehtods.ToDate(model);

                    case "ToTime":
                        return this.Context.DbMehtods.ToTime(model);

                    case "ToString":
                        Check.Exception(model.Args.Count > 1, "ToString (Format) is not supported, Use ToString().If time formatting can be used it.Date.Year+\"-\"+it.Data.Month+\"-\"+it.Date.Day ");
                        return this.Context.DbMehtods.ToString(model);

                    case "ToDecimal":
                        return this.Context.DbMehtods.ToDecimal(model);

                    case "ToGuid":
                        return this.Context.DbMehtods.ToGuid(model);

                    case "ToDouble":
                        return this.Context.DbMehtods.ToDouble(model);

                    case "ToBool":
                        return this.Context.DbMehtods.ToBool(model);

                    case "Substring":
                        return this.Context.DbMehtods.Substring(model);

                    case "Replace":
                        return this.Context.DbMehtods.Replace(model);

                    case "Length":
                        return this.Context.DbMehtods.Length(model);

                    case "AggregateSum":
                        return this.Context.DbMehtods.AggregateSum(model);

                    case "AggregateAvg":
                        return this.Context.DbMehtods.AggregateAvg(model);

                    case "AggregateMin":
                        return this.Context.DbMehtods.AggregateMin(model);

                    case "AggregateMax":
                        return this.Context.DbMehtods.AggregateMax(model);

                    case "AggregateCount":
                        return this.Context.DbMehtods.AggregateCount(model);

                    case nameof(MappingColumn):
                        var mappingColumnResult = this.Context.DbMehtods.MappingColumn(model);
                        var isValid = model.Args[0].IsMember && !model.Args[1].IsMember;
                        Check.Exception(!isValid, "SqlFunc.MappingColumn parameters error, The property name on the left, string value on the right");
                        this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[1].MemberName.ObjToString());
                        return mappingColumnResult;

                    case "IsNull":
                        return this.Context.DbMehtods.IsNull(model);

                    case "MergeString":
                        return this.Context.DbMehtods.MergeString(model.Args.Select(it => it.MemberName.ObjToString()).ToArray());

                    case "GetSelfAndAutoFill":
                        this.Context.Parameters.RemoveAll(it => it.ParameterName == model.Args[0].MemberName.ObjToString());
                        return this.Context.DbMehtods.GetSelfAndAutoFill(model.Args[0].MemberValue.ObjToString(), this.Context.IsSingle);

                    case "GetDate":
                        return this.Context.DbMehtods.GetDate();

                    default:
                        break;
                }
            }
            return null;
        }

        private static Dictionary<string, string> MethodMapping = new Dictionary<string, string> {
            { "ToString","ToString"},
            { "ToInt32","ToInt32"},
            { "ToInt16","ToInt32"},
            { "ToInt64","ToInt64"},
            { "ToDecimal","ToDecimal"},
            { "ToDateTime","ToDate"},
            { "ToBoolean","ToBool"},
            { "ToDouble","ToDouble"},
            { "Length","Length"},
            { "Replace","Replace"},
            { "Contains","Contains"},
            { "ContainsArray","ContainsArray"},
            { "EndsWith","EndsWith"},
            { "StartsWith","StartsWith"},
            { "HasValue","HasValue"},
            { "Trim","Trim"},
            { "Equals","Equals"},
            { "ToLower","ToLower"},
            { "ToUpper","ToUpper"},
            { "Substring","Substring"},
            { "DateAdd","DateAdd"}
        };

        private static Dictionary<string, DateType> MethodTimeMapping = new Dictionary<string, DateType> {
            { "AddYears",DateType.Year},
            { "AddMonths",DateType.Month},
            { "AddDays",DateType.Day},
            { "AddHours",DateType.Hour},
            { "AddMinutes",DateType.Minute},
            { "AddSeconds",DateType.Second},
            { "AddMilliseconds",DateType.Millisecond}
        };

        private bool IsContainsArray(MethodCallExpression express, string methodName, bool isValidNativeMethod)
        {
            return !isValidNativeMethod && express.Method.DeclaringType.Namespace.IsIn("System.Linq", "System.Collections.Generic") && methodName == "Contains";
        }

        private bool IsSubMethod(MethodCallExpression express, string methodName)
        {
            return SubTools.SubItemsConst.Any(it => it.Name == methodName) && express.Object != null && express.Object.Type.Name == "Subqueryable`1";
        }

        private bool CheckMethod(MethodCallExpression expression)
        {
            if (IsExtMethod(expression.Method.Name))
                return true;
            if (expression.Method.ReflectedType().FullName != ExpressionConst.SqlFuncFullName)
                return false;
            else
                return true;
        }
    }
}