// Copyright (c) 2004, 2020, Oracle and/or its affiliates.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License, version 2.0, as
// published by the Free Software Foundation.
//
// This program is also distributed with certain software (including
// but not limited to OpenSSL) that is licensed under separate terms,
// as designated in a particular file or component or in included license
// documentation.  The authors of MySQL hereby grant you an
// additional permission to link the program and your derivative works
// with the separately licensed software that they have included with
// MySQL.
//
// Without limiting anything contained in the foregoing, this file,
// which is part of MySQL Connector/NET, is also subject to the
// Universal FOSS Exception, version 1.0, a copy of which can be found at
// http://oss.oracle.com/licenses/universal-foss-exception.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
// See the GNU General Public License, version 2.0, for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA

using MySql.Data.Types;
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Data.Common;
using System.Globalization;
using System.Reflection;
using System.Text;

namespace MySql.Data.MySqlClient
{
    /// <summary>
    /// Represents a parameter to a <see cref="MySqlCommand"/>, This class cannot be inherited.
    /// </summary>
    [TypeConverter(typeof(MySqlParameterConverter))]
    public sealed partial class MySqlParameter : DbParameter, IDbDataParameter
    {
        private const int UNSIGNED_MASK = 0x8000;
        private object _paramValue;
        private string _paramName;
        private MySqlDbType _mySqlDbType;
        private bool _inferType = true;
        private const int GEOMETRY_LENGTH = 25;
        private DbType _dbType;

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="MySqlParameter"/> class with the parameter name, the <see cref="MySqlParameter.MySqlDbType"/>, the size, and the source column name.
        /// </summary>
        /// <param name="parameterName">The name of the parameter to map. </param>
        /// <param name="dbType">One of the <see cref="MySqlParameter.MySqlDbType"/> values. </param>
        /// <param name="size">The length of the parameter. </param>
        /// <param name="sourceColumn">The name of the source column. </param>
        public MySqlParameter(string parameterName, MySqlDbType dbType, int size, string sourceColumn) : this(parameterName, dbType)
        {
            this.Size = size;
            this.Direction = ParameterDirection.Input;
            this.SourceColumn = sourceColumn;
            this.SourceVersion = DataRowVersion.Default;
        }

        public MySqlParameter()
        {
            this.SourceVersion = DataRowVersion.Default;
            this.Direction = ParameterDirection.Input;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="MySqlParameter"/> class with the parameter name and a value of the new MySqlParameter.
        /// </summary>
        /// <param name="parameterName">The name of the parameter to map. </param>
        /// <param name="value">An <see cref="Object"/> that is the value of the <see cref="MySqlParameter"/>. </param>
        public MySqlParameter(string parameterName, object value) : this()
        {
            this.ParameterName = parameterName;
            this.Value = value;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="MySqlParameter"/> class with the parameter name and the data type.
        /// </summary>
        /// <param name="parameterName">The name of the parameter to map. </param>
        /// <param name="dbType">One of the <see cref="MySqlDbType"/> values. </param>
        public MySqlParameter(string parameterName, MySqlDbType dbType) : this(parameterName, null)
        {
            this.MySqlDbType = dbType;
            this.SetNumericDefaultValueByType(this.MySqlDbType);
        }

        private void SetNumericDefaultValueByType(MySqlDbType mySqlDbType)
        {
            switch (mySqlDbType)
            {
                case MySqlDbType.Decimal:
                case MySqlDbType.Byte:
                case MySqlDbType.Int16:
                case MySqlDbType.Int24:
                case MySqlDbType.Int32:
                case MySqlDbType.Int64:
                case MySqlDbType.Float:
                case MySqlDbType.Double:
                    if (this.Value is null)
                    {
                        this.Value = 0;
                    }

                    break;
            }
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="MySqlParameter"/> class with the parameter name, the <see cref="MySqlDbType"/>, and the size.
        /// </summary>
        /// <param name="parameterName">The name of the parameter to map. </param>
        /// <param name="dbType">One of the <see cref="MySqlDbType"/> values. </param>
        /// <param name="size">The length of the parameter. </param>
        public MySqlParameter(string parameterName, MySqlDbType dbType, int size) : this(parameterName, dbType)
        {
            this.Size = size;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="MySqlParameter"/> class with the parameter name, the type of the parameter, the size of the parameter, a <see cref="ParameterDirection"/>, the precision of the parameter, the scale of the parameter, the source column, a <see cref="DataRowVersion"/> to use, and the value of the parameter.
        /// </summary>
        /// <param name="parameterName">The name of the parameter to map. </param>
        /// <param name="dbType">One of the <see cref="MySqlParameter.MySqlDbType"/> values. </param>
        /// <param name="size">The length of the parameter. </param>
        /// <param name="direction">One of the <see cref="ParameterDirection"/> values. </param>
        /// <param name="isNullable">true if the value of the field can be null, otherwise false. </param>
        /// <param name="precision">The total number of digits to the left and right of the decimal point to which <see cref="MySqlParameter.Value"/> is resolved.</param>
        /// <param name="scale">The total number of decimal places to which <see cref="MySqlParameter.Value"/> is resolved. </param>
        /// <param name="sourceColumn">The name of the source column. </param>
        /// <param name="sourceVersion">One of the <see cref="DataRowVersion"/> values. </param>
        /// <param name="value">An <see cref="Object"/> that is the value of the <see cref="MySqlParameter"/>. </param>
        /// <exception cref="ArgumentException"/>
        public MySqlParameter(string parameterName, MySqlDbType dbType, int size, ParameterDirection direction,
                              bool isNullable, byte precision, byte scale, string sourceColumn,
                              DataRowVersion sourceVersion, object value)
          : this(parameterName, dbType, size, sourceColumn)
        {
            this.Direction = direction;
            this.IsNullable = isNullable;
            this.Precision = precision;
            this.Scale = scale;
            this.Value = value;
            this.SourceVersion = sourceVersion;
        }

        internal MySqlParameter(string name, MySqlDbType type, ParameterDirection dir, string col, DataRowVersion sourceVersion, object val)
          : this(name, type)
        {
            this.Direction = dir;
            this.SourceColumn = col;
            this.Value = val;
            this.SourceVersion = sourceVersion;
        }

        #endregion

        #region Properties

        [Category("Misc")]
        public override String ParameterName
        {
            get { return this._paramName; }
            set { this.SetParameterName(value); }
        }

        internal MySqlParameterCollection Collection { get; set; }
        internal Encoding Encoding { get; set; }

        internal bool TypeHasBeenSet => this._inferType == false;


        internal string BaseName
        {
            get
            {
                if (this.ParameterName.StartsWith("@", StringComparison.Ordinal) || this.ParameterName.StartsWith("?", StringComparison.Ordinal))
                {
                    return this.ParameterName.Substring(1);
                }

                return this.ParameterName;
            }
        }

        /// <summary>
        /// Gets or sets a value indicating whether the parameter is input-only, output-only, bidirectional, or a stored procedure return value parameter.
        /// As of MySql version 4.1 and earlier, input-only is the only valid choice.
        /// </summary>
        [Category("Data")]
        public override ParameterDirection Direction { get; set; }

        /// <summary>
        /// Gets or sets a value indicating whether the parameter accepts null values.
        /// </summary>
        [Browsable(false)]
        public override Boolean IsNullable { get; set; }

        /// <summary>
        /// Gets or sets the <see cref="MySqlParameter.MySqlDbType"/> of the parameter.
        /// </summary>
        [Category("Data")]
        [DbProviderSpecificTypeProperty(true)]
        public MySqlDbType MySqlDbType
        {
            get { return this._mySqlDbType; }
            set
            {
                this.SetMySqlDbType(value);
                this._inferType = false;
            }
        }

        /// <summary>
        /// Gets or sets the maximum number of digits used to represent the <see cref="Value"/> property.
        /// </summary>
        [Category("Data")]
        public override byte Precision { get; set; }

        /// <summary>
        /// Gets or sets the number of decimal places to which <see cref="Value"/> is resolved.
        /// </summary>
        [Category("Data")]
        public override byte Scale { get; set; }

        /// <summary>
        /// Gets or sets the maximum size, in bytes, of the data within the column.
        /// </summary>
        [Category("Data")]
        public override int Size { get; set; }

        /// <summary>
        /// Gets or sets the value of the parameter.
        /// </summary>
        [TypeConverter(typeof(StringConverter))]
        [Category("Data")]
        public override object Value
        {
            get { return this._paramValue; }
            set
            {
                this._paramValue = value;
                byte[] valueAsByte = value as byte[];
                string valueAsString = value as string;

                if (valueAsByte != null)
                {
                    this.Size = valueAsByte.Length;
                }
                else if (valueAsString != null)
                {
                    this.Size = valueAsString.Length;
                }

                if (this._inferType)
                {
                    this.SetTypeFromValue();
                }
            }
        }

        internal IMySqlValue ValueObject { get; private set; }

        /// <summary>
        /// Returns the possible values for this parameter if this parameter is of type
        /// SET or ENUM.  Returns null otherwise.
        /// </summary>
        public IList PossibleValues { get; internal set; }

        /// <summary>
        /// Gets or sets the name of the source column that is mapped to the <see cref="System.Data.DataSet"/> and used for loading or returning the <see cref="MySqlParameter.Value"/>.
        /// </summary>
        [Category("Data")]
        public override String SourceColumn { get; set; }

        /// <summary>
        /// Sets or gets a value which indicates whether the source column is nullable. 
        /// This allows <see cref="DbCommandBuilder"/> to correctly generate Update statements 
        /// for nullable columns. 
        /// </summary>
        public override bool SourceColumnNullMapping { get; set; }

        /// <summary>
        /// Gets or sets the <see cref="DbType"/> of the parameter.
        /// </summary>
        public override DbType DbType
        {
            get { return this._dbType; }
            set
            {
                this.SetDbType(value);
                this._inferType = false;
            }
        }

        #endregion

        private void SetParameterName(string name)
        {
            this.Collection?.ParameterNameChanged(this, this._paramName, name);
            this._paramName = name;
        }

        /// <summary>
        /// Overridden. Gets a string containing the <see cref="ParameterName"/>.
        /// </summary>
        /// <returns></returns>
        public override string ToString() => this._paramName;

        internal int GetPSType()
        {
            switch (this._mySqlDbType)
            {
                case MySqlDbType.Bit:
                    return (int)MySqlDbType.Int64 | UNSIGNED_MASK;
                case MySqlDbType.UByte:
                    return (int)MySqlDbType.Byte | UNSIGNED_MASK;
                case MySqlDbType.UInt64:
                    return (int)MySqlDbType.Int64 | UNSIGNED_MASK;
                case MySqlDbType.UInt32:
                    return (int)MySqlDbType.Int32 | UNSIGNED_MASK;
                case MySqlDbType.UInt24:
                    return (int)MySqlDbType.Int32 | UNSIGNED_MASK;
                case MySqlDbType.UInt16:
                    return (int)MySqlDbType.Int16 | UNSIGNED_MASK;
                case MySqlDbType.Guid:
                    return (int)MySqlDbType.Guid - 600;
                default:
                    int value = (int)this._mySqlDbType;
                    value = value > 255 ? value - 500 : value;
                    return value;
            }
        }

        internal void Serialize(MySqlPacket packet, bool binary, MySqlConnectionStringBuilder settings)
        {
            if (!binary && (this._paramValue == null || this._paramValue == DBNull.Value))
            {
                packet.WriteStringNoNull("NULL");
            }
            else
            {
                if (this.ValueObject.MySqlDbType == MySqlDbType.Guid)
                {
                    MySqlGuid g = (MySqlGuid)this.ValueObject;
                    g.OldGuids = settings.OldGuids;
                    this.ValueObject = g;
                }

                if (this.ValueObject.MySqlDbType == MySqlDbType.Geometry)
                {
                    MySqlGeometry v = (MySqlGeometry)this.ValueObject;
                    if (v.IsNull && this.Value != null)
                    {
                        MySqlGeometry.TryParse(this.Value.ToString(), out v);
                    }

                    this.ValueObject = v;
                }

                this.ValueObject.WriteValue(packet, binary, this._paramValue, this.Size);
            }
        }

        private void SetMySqlDbType(MySqlDbType mysqlDbtype)
        {
            // JSON type is treated as VarChar because in MySQL Server since 8.0.13
            /// MYSQL_TYPE_JSON is not allowed as Item_param lacks a proper
            /// implementation for val_json.
            this._mySqlDbType = mysqlDbtype == MySqlDbType.JSON ? MySqlDbType.VarChar : mysqlDbtype;
            this.ValueObject = MySqlField.GetIMySqlValue(this._mySqlDbType);
            this.SetDbTypeFromMySqlDbType();
        }

        private void SetTypeFromValue()
        {
            if (this._paramValue == null || this._paramValue == DBNull.Value)
            {
                return;
            }

            if (this._paramValue is Guid)
            {
                this.MySqlDbType = MySqlDbType.Guid;
            }
            else if (this._paramValue is TimeSpan)
            {
                this.MySqlDbType = MySqlDbType.Time;
            }
            else if (this._paramValue is bool)
            {
                this.MySqlDbType = MySqlDbType.Byte;
            }
            else
            {
                Type t = this._paramValue.GetType();
                if (t.GetTypeInfo().BaseType == typeof(Enum))
                {
                    t = t.GetTypeInfo().GetEnumUnderlyingType();
                }

                switch (t.Name)
                {
                    case "SByte": this.MySqlDbType = MySqlDbType.Byte; break;
                    case "Byte": this.MySqlDbType = MySqlDbType.UByte; break;
                    case "Int16": this.MySqlDbType = MySqlDbType.Int16; break;
                    case "UInt16": this.MySqlDbType = MySqlDbType.UInt16; break;
                    case "Int32": this.MySqlDbType = MySqlDbType.Int32; break;
                    case "UInt32": this.MySqlDbType = MySqlDbType.UInt32; break;
                    case "Int64": this.MySqlDbType = MySqlDbType.Int64; break;
                    case "UInt64": this.MySqlDbType = MySqlDbType.UInt64; break;
                    case "DateTime": this.MySqlDbType = MySqlDbType.DateTime; break;
                    case "String": this.MySqlDbType = MySqlDbType.VarChar; break;
                    case "Single": this.MySqlDbType = MySqlDbType.Float; break;
                    case "Double": this.MySqlDbType = MySqlDbType.Double; break;
                    case "MySqlGeometry": this.MySqlDbType = MySqlDbType.Geometry; break;
                    case "Decimal": this.MySqlDbType = MySqlDbType.Decimal; break;
                    case "Object":
                    default:
                        this.MySqlDbType = MySqlDbType.Blob;
                        break;
                }
            }
        }

        // this method is pretty dumb but we want it to be fast.  it doesn't return size based
        // on value and type but just on the value.
        internal long EstimatedSize()
        {
            if (this.Value == null || this.Value == DBNull.Value)
            {
                return 4; // size of NULL
            }

            if (this.Value is byte[])
            {
                return ((byte[])this.Value).Length;
            }

            if (this.Value is string)
            {
                return ((string)this.Value).Length * 4; // account for UTF-8 (yeah I know)
            }

            if (this.Value is decimal || this.Value is float)
            {
                return 64;
            }

            return 32;
        }

        /// <summary>
        /// Resets the <b>DbType</b> property to its original settings. 
        /// </summary>
        public override void ResetDbType()
        {
            this._inferType = true;
        }


        void SetDbTypeFromMySqlDbType()
        {
            switch (this._mySqlDbType)
            {
                case MySqlDbType.NewDecimal:
                case MySqlDbType.Decimal:
                    this._dbType = DbType.Decimal;
                    break;
                case MySqlDbType.Byte:
                    this._dbType = DbType.SByte;
                    break;
                case MySqlDbType.UByte:
                    this._dbType = DbType.Byte;
                    break;
                case MySqlDbType.Int16:
                    this._dbType = DbType.Int16;
                    break;
                case MySqlDbType.UInt16:
                    this._dbType = DbType.UInt16;
                    break;
                case MySqlDbType.Int24:
                case MySqlDbType.Int32:
                    this._dbType = DbType.Int32;
                    break;
                case MySqlDbType.UInt24:
                case MySqlDbType.UInt32:
                    this._dbType = DbType.UInt32;
                    break;
                case MySqlDbType.Int64:
                    this._dbType = DbType.Int64;
                    break;
                case MySqlDbType.UInt64:
                    this._dbType = DbType.UInt64;
                    break;
                case MySqlDbType.Bit:
                    this._dbType = DbType.UInt64;
                    break;
                case MySqlDbType.Float:
                    this._dbType = DbType.Single;
                    break;
                case MySqlDbType.Double:
                    this._dbType = DbType.Double;
                    break;
                case MySqlDbType.Timestamp:
                case MySqlDbType.DateTime:
                    this._dbType = DbType.DateTime;
                    break;
                case MySqlDbType.Date:
                case MySqlDbType.Newdate:
                case MySqlDbType.Year:
                    this._dbType = DbType.Date;
                    break;
                case MySqlDbType.Time:
                    this._dbType = DbType.Time;
                    break;
                case MySqlDbType.Enum:
                case MySqlDbType.Set:
                case MySqlDbType.VarChar:
                    this._dbType = DbType.String;
                    break;
                case MySqlDbType.TinyBlob:
                case MySqlDbType.MediumBlob:
                case MySqlDbType.LongBlob:
                case MySqlDbType.Blob:
                    this._dbType = DbType.Object;
                    break;
                case MySqlDbType.String:
                    this._dbType = DbType.StringFixedLength;
                    break;
                case MySqlDbType.Guid:
                    this._dbType = DbType.Guid;
                    break;
            }
        }

        private void SetDbType(DbType dbType)
        {
            this._dbType = dbType;
            switch (this._dbType)
            {
                case DbType.Guid:
                    this._mySqlDbType = MySqlDbType.Guid;
                    break;

                case DbType.AnsiString:
                case DbType.String:
                    this._mySqlDbType = MySqlDbType.VarChar;
                    break;

                case DbType.AnsiStringFixedLength:
                case DbType.StringFixedLength:
                    this._mySqlDbType = MySqlDbType.String;
                    break;

                case DbType.Boolean:
                case DbType.Byte:
                    this._mySqlDbType = MySqlDbType.UByte;
                    break;

                case DbType.SByte:
                    this._mySqlDbType = MySqlDbType.Byte;
                    break;

                case DbType.Date:
                    this._mySqlDbType = MySqlDbType.Date;
                    break;
                case DbType.DateTime:
                    this._mySqlDbType = MySqlDbType.DateTime;
                    break;

                case DbType.Time:
                    this._mySqlDbType = MySqlDbType.Time;
                    break;
                case DbType.Single:
                    this._mySqlDbType = MySqlDbType.Float;
                    break;
                case DbType.Double:
                    this._mySqlDbType = MySqlDbType.Double;
                    break;

                case DbType.Int16:
                    this._mySqlDbType = MySqlDbType.Int16;
                    break;
                case DbType.UInt16:
                    this._mySqlDbType = MySqlDbType.UInt16;
                    break;

                case DbType.Int32:
                    this._mySqlDbType = MySqlDbType.Int32;
                    break;
                case DbType.UInt32:
                    this._mySqlDbType = MySqlDbType.UInt32;
                    break;

                case DbType.Int64:
                    this._mySqlDbType = MySqlDbType.Int64;
                    break;
                case DbType.UInt64:
                    this._mySqlDbType = MySqlDbType.UInt64;
                    break;

                case DbType.Decimal:
                case DbType.Currency:
                    this._mySqlDbType = MySqlDbType.Decimal;
                    break;

                case DbType.Object:
                case DbType.VarNumeric:
                case DbType.Binary:
                default:
                    this._mySqlDbType = MySqlDbType.Blob;
                    break;
            }

            if (this._dbType == DbType.Object)
            {
                var value = this._paramValue as byte[];
                if (value != null && value.Length == GEOMETRY_LENGTH)
                {
                    this._mySqlDbType = MySqlDbType.Geometry;
                }
            }

            this.ValueObject = MySqlField.GetIMySqlValue(this._mySqlDbType);
        }
    }



    internal class MySqlParameterConverter : TypeConverter
    {

        public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
        {
            if (destinationType == typeof(System.ComponentModel.Design.Serialization.InstanceDescriptor))
            {
                return true;
            }

            // Always call the base to see if it can perform the conversion.
            return base.CanConvertTo(context, destinationType);
        }

        public override object ConvertTo(
            ITypeDescriptorContext context,
                                         CultureInfo culture, object value, Type destinationType)
        {
            if (destinationType == typeof(System.ComponentModel.Design.Serialization.InstanceDescriptor))
            {
                ConstructorInfo ci = typeof(MySqlParameter).GetConstructor(
                    new[]
                                    {
                                typeof (string), typeof (MySqlDbType), typeof (int), typeof (ParameterDirection),
                                typeof (bool), typeof (byte), typeof (byte), typeof (string),
                                typeof (object)
                                    });
                MySqlParameter p = (MySqlParameter)value;
                return new System.ComponentModel.Design.Serialization.InstanceDescriptor(ci, new object[]
                                                                  {
                                                              p.ParameterName, p.DbType, p.Size, p.Direction,
                                                              p.IsNullable, p.Precision,
                                                              p.Scale, p.SourceColumn, p.Value
                                                                  });
            }

            // Always call base, even if you can't convert.
            return base.ConvertTo(context, culture, value, destinationType);
        }

    }
}