//------------------------------------------------------------------------------
// <copyright file="XmlSchemaFacet.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
//------------------------------------------------------------------------------

namespace System.Xml.Schema {

    using System;
    using System.ComponentModel;
    using System.Xml.Serialization;
    using System.Xml.Schema;
    using System.Xml.XPath;
    using System.Diagnostics;
    using System.Collections;
    using System.Text;
    using System.Text.RegularExpressions;
    using System.Threading;
    using System.Globalization;

    /// <include file='doc\XmlSchemaFacet.uex' path='docs/doc[@for="XmlSchemaFacet"]/*' />
    internal abstract class FacetsChecker {

    private struct FacetsCompiler {
        DatatypeImplementation datatype;
        RestrictionFacets derivedRestriction;
        
        RestrictionFlags baseFlags; 
        RestrictionFlags baseFixedFlags; 
        RestrictionFlags validRestrictionFlags; 
        
        //Helpers
        XmlSchemaDatatype nonNegativeInt; 
        XmlSchemaDatatype builtInType;
        XmlTypeCode builtInEnum;

        bool firstPattern;
        StringBuilder regStr;
        XmlSchemaPatternFacet pattern_facet;

        public FacetsCompiler(DatatypeImplementation baseDatatype, RestrictionFacets restriction) {
            firstPattern = true;
            regStr = null;
            pattern_facet = null;
            datatype = baseDatatype;
            derivedRestriction = restriction;
            baseFlags = datatype.Restriction != null ? datatype.Restriction.Flags : 0;
            baseFixedFlags = datatype.Restriction != null ? datatype.Restriction.FixedFlags : 0;
            validRestrictionFlags = datatype.ValidRestrictionFlags;
            nonNegativeInt = DatatypeImplementation.GetSimpleTypeFromTypeCode(XmlTypeCode.NonNegativeInteger).Datatype;
            builtInEnum = !(datatype is Datatype_union || datatype is Datatype_List) ? datatype.TypeCode : 0;
            builtInType = (int)builtInEnum > 0 ? DatatypeImplementation.GetSimpleTypeFromTypeCode(builtInEnum).Datatype : datatype;
        }

        internal void CompileLengthFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.Length, Res.Sch_LengthFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.Length, Res.Sch_DupLengthFacet);
            derivedRestriction.Length = XmlBaseConverter.DecimalToInt32((decimal)ParseFacetValue(nonNegativeInt, facet, Res.Sch_LengthFacetInvalid, null, null));
            
            if ((baseFixedFlags & RestrictionFlags.Length) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.Length, derivedRestriction.Length)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.Length) != 0) {
                if (datatype.Restriction.Length < derivedRestriction.Length) {
                    throw new XmlSchemaException(Res.Sch_LengthGtBaseLength, facet);
                }
            }
            // If the base has the MinLength facet, check that our derived length is not violating it
            if ((baseFlags & RestrictionFlags.MinLength) != 0) {
                if (datatype.Restriction.MinLength > derivedRestriction.Length) {
                    throw new XmlSchemaException(Res.Sch_MaxMinLengthBaseLength, facet);
                }
            }
            // If the base has the MaxLength facet, check that our derived length is not violating it
            if ((baseFlags & RestrictionFlags.MaxLength) != 0) {
                if (datatype.Restriction.MaxLength < derivedRestriction.Length) {
                    throw new XmlSchemaException(Res.Sch_MaxMinLengthBaseLength, facet);
                }
            }
            SetFlag(facet, RestrictionFlags.Length);
        }

        internal void CompileMinLengthFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MinLength, Res.Sch_MinLengthFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MinLength, Res.Sch_DupMinLengthFacet);
            derivedRestriction.MinLength = XmlBaseConverter.DecimalToInt32((decimal)ParseFacetValue(nonNegativeInt, facet, Res.Sch_MinLengthFacetInvalid, null, null));
            
            if ((baseFixedFlags & RestrictionFlags.MinLength) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MinLength, derivedRestriction.MinLength)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.MinLength) != 0) {
                if (datatype.Restriction.MinLength > derivedRestriction.MinLength) {
                    throw new XmlSchemaException(Res.Sch_MinLengthGtBaseMinLength, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.Length) != 0) {
                if (datatype.Restriction.Length < derivedRestriction.MinLength) {
                    throw new XmlSchemaException(Res.Sch_MaxMinLengthBaseLength, facet);
                }
            }
            SetFlag(facet, RestrictionFlags.MinLength);
        }

        internal void CompileMaxLengthFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MaxLength, Res.Sch_MaxLengthFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MaxLength, Res.Sch_DupMaxLengthFacet);
            derivedRestriction.MaxLength = XmlBaseConverter.DecimalToInt32((decimal)ParseFacetValue(nonNegativeInt, facet, Res.Sch_MaxLengthFacetInvalid, null, null));

            if ((baseFixedFlags & RestrictionFlags.MaxLength) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MaxLength, derivedRestriction.MaxLength)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.MaxLength) != 0) {
                if (datatype.Restriction.MaxLength < derivedRestriction.MaxLength) {
                    throw new XmlSchemaException(Res.Sch_MaxLengthGtBaseMaxLength, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.Length) != 0) {
                if (datatype.Restriction.Length > derivedRestriction.MaxLength) {
                    throw new XmlSchemaException(Res.Sch_MaxMinLengthBaseLength, facet);
                }
            }
            SetFlag(facet, RestrictionFlags.MaxLength);
        }

        internal void CompilePatternFacet(XmlSchemaPatternFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.Pattern, Res.Sch_PatternFacetProhibited);
            if(firstPattern == true) {
                regStr = new StringBuilder();
                regStr.Append("(");
                regStr.Append(facet.Value);
                pattern_facet = facet;
                firstPattern = false;
            }
            else {
                regStr.Append(")|(");
                regStr.Append(facet.Value);
            }
            SetFlag(facet, RestrictionFlags.Pattern);
        }

        internal void CompileEnumerationFacet(XmlSchemaFacet facet, IXmlNamespaceResolver nsmgr, XmlNameTable nameTable) {
            CheckProhibitedFlag(facet, RestrictionFlags.Enumeration, Res.Sch_EnumerationFacetProhibited);
            if (derivedRestriction.Enumeration == null) {
                derivedRestriction.Enumeration = new ArrayList();
            }
            derivedRestriction.Enumeration.Add(ParseFacetValue(datatype, facet, Res.Sch_EnumerationFacetInvalid, nsmgr, nameTable));
            SetFlag(facet, RestrictionFlags.Enumeration);
        }

        internal void CompileWhitespaceFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.WhiteSpace, Res.Sch_WhiteSpaceFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.WhiteSpace, Res.Sch_DupWhiteSpaceFacet);
            if (facet.Value == "preserve") {
                derivedRestriction.WhiteSpace = XmlSchemaWhiteSpace.Preserve;
            }
            else if (facet.Value == "replace") {
                derivedRestriction.WhiteSpace = XmlSchemaWhiteSpace.Replace;
            }
            else if (facet.Value == "collapse") {
                derivedRestriction.WhiteSpace = XmlSchemaWhiteSpace.Collapse;
            }
            else {
                throw new XmlSchemaException(Res.Sch_InvalidWhiteSpace, facet.Value, facet);
            }
            if ((baseFixedFlags & RestrictionFlags.WhiteSpace) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.WhiteSpace, derivedRestriction.WhiteSpace)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            //Check base and derived whitespace facets
            XmlSchemaWhiteSpace baseWhitespace;
            if ((baseFlags & RestrictionFlags.WhiteSpace) != 0) {
                baseWhitespace = datatype.Restriction.WhiteSpace;
            }
            else {
                baseWhitespace = datatype.BuiltInWhitespaceFacet;
            }
            if ( baseWhitespace == XmlSchemaWhiteSpace.Collapse &&
                (derivedRestriction.WhiteSpace == XmlSchemaWhiteSpace.Replace || derivedRestriction.WhiteSpace == XmlSchemaWhiteSpace.Preserve)
            ) {
                throw new XmlSchemaException(Res.Sch_WhiteSpaceRestriction1, facet);
            }
            if (baseWhitespace == XmlSchemaWhiteSpace.Replace &&
                derivedRestriction.WhiteSpace == XmlSchemaWhiteSpace.Preserve
            ) {
                throw new XmlSchemaException(Res.Sch_WhiteSpaceRestriction2, facet);
            }
            SetFlag(facet, RestrictionFlags.WhiteSpace);
        }

        internal void CompileMaxInclusiveFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MaxInclusive, Res.Sch_MaxInclusiveFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MaxInclusive, Res.Sch_DupMaxInclusiveFacet);
            derivedRestriction.MaxInclusive = ParseFacetValue(builtInType, facet, Res.Sch_MaxInclusiveFacetInvalid, null, null);
            
            if ((baseFixedFlags & RestrictionFlags.MaxInclusive) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MaxInclusive, derivedRestriction.MaxInclusive)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            CheckValue(derivedRestriction.MaxInclusive, facet);
            SetFlag(facet, RestrictionFlags.MaxInclusive);
        }

        internal void CompileMaxExclusiveFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MaxExclusive, Res.Sch_MaxExclusiveFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MaxExclusive, Res.Sch_DupMaxExclusiveFacet);
            derivedRestriction.MaxExclusive = ParseFacetValue(builtInType, facet, Res.Sch_MaxExclusiveFacetInvalid, null, null);
            
            if ((baseFixedFlags & RestrictionFlags.MaxExclusive) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MaxExclusive, derivedRestriction.MaxExclusive)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            CheckValue(derivedRestriction.MaxExclusive, facet);
            SetFlag(facet, RestrictionFlags.MaxExclusive);
        }

        internal void CompileMinInclusiveFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MinInclusive, Res.Sch_MinInclusiveFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MinInclusive, Res.Sch_DupMinInclusiveFacet);
            derivedRestriction.MinInclusive = ParseFacetValue(builtInType, facet, Res.Sch_MinInclusiveFacetInvalid, null, null);

            if ((baseFixedFlags & RestrictionFlags.MinInclusive) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MinInclusive, derivedRestriction.MinInclusive)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            CheckValue(derivedRestriction.MinInclusive, facet);
            SetFlag(facet, RestrictionFlags.MinInclusive);
        }

        internal void CompileMinExclusiveFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.MinExclusive, Res.Sch_MinExclusiveFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.MinExclusive, Res.Sch_DupMinExclusiveFacet);
            derivedRestriction.MinExclusive = ParseFacetValue(builtInType, facet, Res.Sch_MinExclusiveFacetInvalid, null, null);

            if ((baseFixedFlags & RestrictionFlags.MinExclusive) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.MinExclusive, derivedRestriction.MinExclusive)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            CheckValue(derivedRestriction.MinExclusive, facet);
            SetFlag(facet, RestrictionFlags.MinExclusive);
        }

        internal void CompileTotalDigitsFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.TotalDigits, Res.Sch_TotalDigitsFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.TotalDigits, Res.Sch_DupTotalDigitsFacet);
            XmlSchemaDatatype positiveInt = DatatypeImplementation.GetSimpleTypeFromTypeCode(XmlTypeCode.PositiveInteger).Datatype;                        
            derivedRestriction.TotalDigits = XmlBaseConverter.DecimalToInt32((decimal)ParseFacetValue(positiveInt, facet, Res.Sch_TotalDigitsFacetInvalid, null, null));
            
            if ((baseFixedFlags & RestrictionFlags.TotalDigits) != 0) {
                if (!datatype.IsEqual(datatype.Restriction.TotalDigits, derivedRestriction.TotalDigits)) {
                    throw new XmlSchemaException(Res.Sch_FacetBaseFixed, facet);
                }
            }
            if ((baseFlags & RestrictionFlags.TotalDigits) != 0) {
                if(derivedRestriction.TotalDigits > datatype.Restriction.TotalDigits) {
                    throw new XmlSchemaException(Res.Sch_TotalDigitsMismatch, string.Empty);
                }
            }
            SetFlag(facet, RestrictionFlags.TotalDigits);
        }

        internal void CompileFractionDigitsFacet(XmlSchemaFacet facet) {
            CheckProhibitedFlag(facet, RestrictionFlags.FractionDigits, Res.Sch_FractionDigitsFacetProhibited);
            CheckDupFlag(facet, RestrictionFlags.FractionDigits, Res.Sch_DupFractionDigitsFacet);
            derivedRestriction.FractionDigits = XmlBaseConverter.DecimalToInt32((decimal)ParseFacetValue(nonNegativeInt, facet, Res.Sch_FractionDigitsFacetInvalid, null, null));

            if ((derivedRestriction.FractionDigits != 0) && (datatype.TypeCode != XmlTypeCode.Decimal)) {
                throw new XmlSchemaException(Res.Sch_FractionDigitsFacetInvalid, Res.GetString(Res.Sch_FractionDigitsNotOnDecimal), facet);
            }
            if ((baseFlags & RestrictionFlags.FractionDigits) != 0) {
                if (derivedRestriction.FractionDigits > datatype.Restriction.FractionDigits) {
                    throw new XmlSchemaException(Res.Sch_TotalDigitsMismatch, string.Empty);
                }
            }
            SetFlag(facet, RestrictionFlags.FractionDigits);
        }

        internal void FinishFacetCompile() {
            //Additional check for pattern facet
            //If facet is XMLSchemaPattern, then the String built inside the loop
            //needs to be converted to a RegEx
            if(firstPattern == false) {
                if (derivedRestriction.Patterns == null) {
                    derivedRestriction.Patterns = new ArrayList();
                }
                try {
                    regStr.Append(")");
                    string tempStr = regStr.ToString();
                    if(tempStr.IndexOf('|') != -1) { // ordinal compare
                        regStr.Insert(0,"(");
                        regStr.Append(")");
                    }
                   derivedRestriction.Patterns.Add(new Regex(Preprocess(regStr.ToString()), RegexOptions.None));

                } catch (Exception e) {
                    throw new XmlSchemaException(Res.Sch_PatternFacetInvalid, new string[] {e.Message}, e, pattern_facet.SourceUri, pattern_facet.LineNumber, pattern_facet.LinePosition, pattern_facet);
                }
            }
        }

        private void CheckValue(object value, XmlSchemaFacet facet) {
            RestrictionFacets restriction = datatype.Restriction;
            switch (facet.FacetType) {
                case FacetType.MaxInclusive:
                    if ((baseFlags & RestrictionFlags.MaxInclusive) != 0) { //Base facet has maxInclusive
                        if (datatype.Compare(value, restriction.MaxInclusive) > 0) {
                            throw new XmlSchemaException(Res.Sch_MaxInclusiveMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MaxExclusive) != 0) { //Base facet has maxExclusive
                        if (datatype.Compare(value, restriction.MaxExclusive) >= 0) {
                            throw new XmlSchemaException(Res.Sch_MaxIncExlMismatch, string.Empty);
                        }
                    }
                break;

                case FacetType.MaxExclusive:
                    if ((baseFlags & RestrictionFlags.MaxExclusive) != 0) { //Base facet has maxExclusive
                        if (datatype.Compare(value, restriction.MaxExclusive) > 0) {
                            throw new XmlSchemaException(Res.Sch_MaxExclusiveMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MaxInclusive) != 0) { //Base facet has maxInclusive
                        if (datatype.Compare(value, restriction.MaxInclusive) > 0) {
                            throw new XmlSchemaException(Res.Sch_MaxExlIncMismatch, string.Empty);
                        }
                    }
                break;

                case FacetType.MinInclusive:
                    if ((baseFlags & RestrictionFlags.MinInclusive) != 0) { //Base facet has minInclusive
                        if (datatype.Compare(value, restriction.MinInclusive) < 0) {
                            throw new XmlSchemaException(Res.Sch_MinInclusiveMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MinExclusive) != 0) { //Base facet has minExclusive
                        if (datatype.Compare(value, restriction.MinExclusive) < 0) {
                            throw new XmlSchemaException(Res.Sch_MinIncExlMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MaxExclusive) != 0) { //Base facet has maxExclusive
                        if (datatype.Compare(value, restriction.MaxExclusive) >= 0) {
                            throw new XmlSchemaException(Res.Sch_MinIncMaxExlMismatch, string.Empty);
                        }
                    }
                break;

                case FacetType.MinExclusive:
                    if ((baseFlags & RestrictionFlags.MinExclusive) != 0) { //Base facet has minExclusive
                        if (datatype.Compare(value, restriction.MinExclusive) < 0) {
                            throw new XmlSchemaException(Res.Sch_MinExclusiveMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MinInclusive) != 0) { //Base facet has minInclusive
                        if (datatype.Compare(value, restriction.MinInclusive) < 0) {
                            throw new XmlSchemaException(Res.Sch_MinExlIncMismatch, string.Empty);
                        }
                    }
                    if ((baseFlags & RestrictionFlags.MaxExclusive) != 0) { //Base facet has maxExclusive
                        if (datatype.Compare(value, restriction.MaxExclusive) >= 0) {
                            throw new XmlSchemaException(Res.Sch_MinExlMaxExlMismatch, string.Empty);
                        }
                    }
                break;

                default:
                    Debug.Assert(false);
                break;
            }
        }

        internal void CompileFacetCombinations() {
            RestrictionFacets baseRestriction = datatype.Restriction;
            //They are not allowed on the same type but allowed on derived types.
            if (
                (derivedRestriction.Flags & RestrictionFlags.MaxInclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxExclusive) != 0
            ) {
                throw new XmlSchemaException(Res.Sch_MaxInclusiveExclusive, string.Empty);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinInclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MinExclusive) != 0
            ) {
                throw new XmlSchemaException(Res.Sch_MinInclusiveExclusive, string.Empty);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.Length) != 0 &&
                (derivedRestriction.Flags & (RestrictionFlags.MinLength|RestrictionFlags.MaxLength)) != 0
            ) {
                throw new XmlSchemaException(Res.Sch_LengthAndMinMax, string.Empty);
            }
            
            CopyFacetsFromBaseType();

            // Check combinations
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinLength) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxLength) != 0
            ) {
                if (derivedRestriction.MinLength > derivedRestriction.MaxLength) {
                    throw new XmlSchemaException(Res.Sch_MinLengthGtMaxLength, string.Empty);
                }
            }

            //
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinInclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxInclusive) != 0
            ) {
                if (datatype.Compare(derivedRestriction.MinInclusive, derivedRestriction.MaxInclusive) > 0) {
                    throw new XmlSchemaException(Res.Sch_MinInclusiveGtMaxInclusive, string.Empty);
                }
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinInclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxExclusive) != 0
            ) {
                if (datatype.Compare(derivedRestriction.MinInclusive, derivedRestriction.MaxExclusive) > 0) {
                    throw new XmlSchemaException(Res.Sch_MinInclusiveGtMaxExclusive, string.Empty);
                }
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinExclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxExclusive) != 0
            ) {
                if (datatype.Compare(derivedRestriction.MinExclusive, derivedRestriction.MaxExclusive) > 0) {
                    throw new XmlSchemaException(Res.Sch_MinExclusiveGtMaxExclusive, string.Empty);
                }
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinExclusive) != 0 &&
                (derivedRestriction.Flags & RestrictionFlags.MaxInclusive) != 0
            ) {
                if (datatype.Compare(derivedRestriction.MinExclusive, derivedRestriction.MaxInclusive) > 0) {
                    throw new XmlSchemaException(Res.Sch_MinExclusiveGtMaxInclusive, string.Empty);
                }
            }
            if ((derivedRestriction.Flags & (RestrictionFlags.TotalDigits|RestrictionFlags.FractionDigits)) == (RestrictionFlags.TotalDigits|RestrictionFlags.FractionDigits)) {
                if (derivedRestriction.FractionDigits > derivedRestriction.TotalDigits) {
                    throw new XmlSchemaException(Res.Sch_FractionDigitsGtTotalDigits, string.Empty);
                }
            }
        }

        private void CopyFacetsFromBaseType() {
            RestrictionFacets baseRestriction = datatype.Restriction;
            // Copy additional facets from the base type
            if (
                (derivedRestriction.Flags & RestrictionFlags.Length) == 0 &&
                (baseFlags & RestrictionFlags.Length) != 0
            ) {
                derivedRestriction.Length = baseRestriction.Length;
                SetFlag(RestrictionFlags.Length);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinLength) == 0 &&
                (baseFlags & RestrictionFlags.MinLength) != 0
            ) {
                derivedRestriction.MinLength = baseRestriction.MinLength;
                SetFlag(RestrictionFlags.MinLength);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MaxLength) == 0 &&
                (baseFlags & RestrictionFlags.MaxLength) != 0
            ) {
                derivedRestriction.MaxLength = baseRestriction.MaxLength;
                SetFlag(RestrictionFlags.MaxLength);
            }
            if ((baseFlags & RestrictionFlags.Pattern) != 0) {
                if (derivedRestriction.Patterns == null) {
                    derivedRestriction.Patterns = baseRestriction.Patterns;
                }
                else {
                    derivedRestriction.Patterns.AddRange(baseRestriction.Patterns);
                }
                SetFlag(RestrictionFlags.Pattern);
            }

            if ((baseFlags & RestrictionFlags.Enumeration) != 0) {
                if (derivedRestriction.Enumeration == null) {
                    derivedRestriction.Enumeration = baseRestriction.Enumeration;
                }
                SetFlag(RestrictionFlags.Enumeration);
            }

            if (
                (derivedRestriction.Flags & RestrictionFlags.WhiteSpace) == 0 &&
                (baseFlags & RestrictionFlags.WhiteSpace) != 0
            ) {
                derivedRestriction.WhiteSpace = baseRestriction.WhiteSpace;
                SetFlag(RestrictionFlags.WhiteSpace);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MaxInclusive) == 0 &&
                (baseFlags & RestrictionFlags.MaxInclusive) != 0
            ) {
                derivedRestriction.MaxInclusive = baseRestriction.MaxInclusive;
                SetFlag(RestrictionFlags.MaxInclusive);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MaxExclusive) == 0 &&
                (baseFlags & RestrictionFlags.MaxExclusive) != 0
            ) {
                derivedRestriction.MaxExclusive = baseRestriction.MaxExclusive;
                SetFlag(RestrictionFlags.MaxExclusive);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinInclusive) == 0 &&
                (baseFlags & RestrictionFlags.MinInclusive) != 0
            ) {
                derivedRestriction.MinInclusive = baseRestriction.MinInclusive;
                SetFlag(RestrictionFlags.MinInclusive);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.MinExclusive) == 0 &&
                (baseFlags & RestrictionFlags.MinExclusive) != 0
            ) {
                derivedRestriction.MinExclusive = baseRestriction.MinExclusive;
                SetFlag(RestrictionFlags.MinExclusive);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.TotalDigits) == 0 &&
                (baseFlags & RestrictionFlags.TotalDigits) != 0
            ) {
                derivedRestriction.TotalDigits = baseRestriction.TotalDigits;
                SetFlag(RestrictionFlags.TotalDigits);
            }
            if (
                (derivedRestriction.Flags & RestrictionFlags.FractionDigits) == 0 &&
                (baseFlags & RestrictionFlags.FractionDigits) != 0
            ) {
                derivedRestriction.FractionDigits = baseRestriction.FractionDigits;
                SetFlag(RestrictionFlags.FractionDigits);
            }
        }

        private object ParseFacetValue(XmlSchemaDatatype datatype, XmlSchemaFacet facet, string code, IXmlNamespaceResolver nsmgr, XmlNameTable nameTable) {
            object typedValue;
            Exception ex = datatype.TryParseValue(facet.Value, nameTable, nsmgr, out typedValue);
            if (ex == null) {
                return typedValue;
            }
            else {
                throw new XmlSchemaException(code, new string[] {ex.Message} , ex, facet.SourceUri, facet.LineNumber, facet.LinePosition, facet);
            }
        }

        private struct Map {
            internal Map(char m, string r) {
                match = m;
                replacement = r;
            }
            internal char match;
            internal string replacement;
        };

        private static readonly Map[] c_map = {
            new Map('c', "\\p{_xmlC}"),
            new Map('C', "\\P{_xmlC}"),
            new Map('d', "\\p{_xmlD}"),
            new Map('D', "\\P{_xmlD}"),
            new Map('i', "\\p{_xmlI}"),
            new Map('I', "\\P{_xmlI}"),
            new Map('w', "\\p{_xmlW}"),
            new Map('W', "\\P{_xmlW}"),
        };
        private static string Preprocess(string pattern) {
            StringBuilder bufBld = new StringBuilder();
            bufBld.Append("^");

            char[] source = pattern.ToCharArray();
            int length = pattern.Length;
            int copyPosition = 0;
            for (int position = 0; position < length - 2; position ++) {
                if (source[position] == '\\') {
                    if (source[position + 1] == '\\') {
                        position ++; // skip it
                    }
                    else {
                        char ch = source[position + 1];
                        for (int i = 0; i < c_map.Length; i++) {
                            if (c_map[i].match == ch) {
                                if (copyPosition < position) {
                                    bufBld.Append(source, copyPosition, position - copyPosition);
                                }
                                bufBld.Append(c_map[i].replacement);
                                position ++;
                                copyPosition = position + 1;
                                break;
                            }
                        }
                    }
                }
            }
            if (copyPosition < length) {
                bufBld.Append(source, copyPosition, length - copyPosition);
            }

            bufBld.Append("$");
            return bufBld.ToString();
        }

        private void CheckProhibitedFlag(XmlSchemaFacet facet, RestrictionFlags flag, string errorCode) {
            if ((validRestrictionFlags & flag) == 0) {
                throw new XmlSchemaException(errorCode, datatype.TypeCodeString, facet);
            }
        }

        private void CheckDupFlag(XmlSchemaFacet facet, RestrictionFlags flag, string errorCode) {
            if ((derivedRestriction.Flags & flag) != 0) {
                throw new XmlSchemaException(errorCode, facet);
            }
        }

        private void SetFlag(XmlSchemaFacet facet, RestrictionFlags flag) {
            derivedRestriction.Flags |= flag;
            if (facet.IsFixed) {
                derivedRestriction.FixedFlags |= flag;
            }
        }

        private void SetFlag(RestrictionFlags flag) {
            derivedRestriction.Flags |= flag;
            if ((baseFixedFlags & flag) != 0) {
                derivedRestriction.FixedFlags |= flag;
            }
        }

    }
        
        internal virtual Exception CheckLexicalFacets(ref string parseString, XmlSchemaDatatype datatype) {
            CheckWhitespaceFacets(ref parseString, datatype);
            return CheckPatternFacets(datatype.Restriction, parseString);
        }
        internal virtual Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(decimal value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(Int64 value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(Int32 value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(Int16 value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(byte value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(DateTime value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(double value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(float value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(string value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(byte[] value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(TimeSpan value, XmlSchemaDatatype datatype) {
            return null;
        }
        internal virtual Exception CheckValueFacets(XmlQualifiedName value, XmlSchemaDatatype datatype) {
            return null;
        }
        
        internal void CheckWhitespaceFacets(ref string s, XmlSchemaDatatype datatype) {
            // before parsing, check whitespace facet
            RestrictionFacets restriction = datatype.Restriction;

            switch (datatype.Variety) {
                case XmlSchemaDatatypeVariety.List:
                    s = s.Trim();
                break;

                case XmlSchemaDatatypeVariety.Atomic:
                    if (datatype.BuiltInWhitespaceFacet == XmlSchemaWhiteSpace.Collapse) {
                        s = XmlComplianceUtil.NonCDataNormalize(s);
                    }
                    else if (datatype.BuiltInWhitespaceFacet == XmlSchemaWhiteSpace.Replace) {
                        s = XmlComplianceUtil.CDataNormalize(s);
                    }
                    else if (restriction != null && (restriction.Flags & RestrictionFlags.WhiteSpace) != 0) { //Restriction has whitespace facet specified
                        if (restriction.WhiteSpace == XmlSchemaWhiteSpace.Replace) {
                            s = XmlComplianceUtil.CDataNormalize(s);
                        }
                        else if (restriction.WhiteSpace == XmlSchemaWhiteSpace.Collapse) {
                            s = XmlComplianceUtil.NonCDataNormalize(s);
                        }
                    }
                break;

                default:
                break;

            }
        }
        internal Exception CheckPatternFacets(RestrictionFacets restriction, string value) {
            if (restriction != null && (restriction.Flags & RestrictionFlags.Pattern) != 0) {
                for (int i = 0; i < restriction.Patterns.Count; ++i) {
                    Regex regex = (Regex)restriction.Patterns[i];
                    if (!regex.IsMatch(value)) {
                        return new XmlSchemaException(Res.Sch_PatternConstraintFailed, string.Empty);
                    }
                }
            }
            return null;
        }
        
        internal virtual bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return false;
        }

        //Compile-time Facet Checking
        internal virtual RestrictionFacets ConstructRestriction(DatatypeImplementation datatype, XmlSchemaObjectCollection facets, XmlNameTable nameTable) {
            //Datatype is the type on which this method is called
            RestrictionFacets derivedRestriction = new RestrictionFacets();
            FacetsCompiler facetCompiler = new FacetsCompiler(datatype, derivedRestriction);

            for (int i = 0; i < facets.Count; ++i) {
                XmlSchemaFacet facet = (XmlSchemaFacet)facets[i];
                if (facet.Value == null) {
                    throw new XmlSchemaException(Res.Sch_InvalidFacet, facet);
                }
                IXmlNamespaceResolver nsmgr = new SchemaNamespaceManager(facet);
                switch(facet.FacetType) {
                    case FacetType.Length:
                        facetCompiler.CompileLengthFacet(facet);
                    break;

                    case FacetType.MinLength:
                        facetCompiler.CompileMinLengthFacet(facet);
                    break;

                    case FacetType.MaxLength:
                        facetCompiler.CompileMaxLengthFacet(facet);
                    break;
    
                    case FacetType.Pattern:
                        facetCompiler.CompilePatternFacet(facet as XmlSchemaPatternFacet);
                    break;

                    case FacetType.Enumeration:
                        facetCompiler.CompileEnumerationFacet(facet, nsmgr, nameTable);                        
                    break;

                    case FacetType.Whitespace:
                        facetCompiler.CompileWhitespaceFacet(facet);
                    break;

                    case FacetType.MinInclusive:
                        facetCompiler.CompileMinInclusiveFacet(facet);
                    break;

                    case FacetType.MinExclusive:
                        facetCompiler.CompileMinExclusiveFacet(facet);
                    break;

                    case FacetType.MaxInclusive:
                        facetCompiler.CompileMaxInclusiveFacet(facet);
                    break;

                    case FacetType.MaxExclusive:
                        facetCompiler.CompileMaxExclusiveFacet(facet);
                    break;

                    case FacetType.TotalDigits:
                        facetCompiler.CompileTotalDigitsFacet(facet);
                    break;

                    case FacetType.FractionDigits:
                        facetCompiler.CompileFractionDigitsFacet(facet);
                    break;

                    default:
                        throw new XmlSchemaException(Res.Sch_UnknownFacet, facet);
                }
            }
            facetCompiler.FinishFacetCompile();
            facetCompiler.CompileFacetCombinations();
            return derivedRestriction;
        }

        

        

        internal static decimal Power(int x, int y) {
            //Returns X raised to the power Y
            decimal returnValue = 1m;
            decimal decimalValue = (decimal)x;
            if ( y > 28 ) { //CLR decimal cannot handle more than 29 digits (10 power 28.)
                return decimal.MaxValue;
            }
            for (int i = 0; i < y; i++) {
                returnValue = returnValue * decimalValue;
            }
            return returnValue;
        }
    }
    

    internal class Numeric10FacetsChecker : FacetsChecker {
        static readonly char[] signs = new char[] {'+', '-'};
        decimal maxValue;
        decimal minValue;

        internal Numeric10FacetsChecker(decimal minVal, decimal maxVal) {
            minValue = minVal;
            maxValue = maxVal;
        }
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {

            decimal decimalValue = datatype.ValueConverter.ToDecimal(value);
            return CheckValueFacets(decimalValue, datatype);
        }

        internal override Exception CheckValueFacets(decimal value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            XmlValueConverter valueConverter = datatype.ValueConverter;
            
            //Check built-in facets
            if (value > maxValue || value < minValue) {
                return new OverflowException(Res.GetString(Res.XmlConvert_Overflow, value.ToString(CultureInfo.InvariantCulture), datatype.TypeCodeString));
            }
            //Check user-defined facets
            if (flags != 0) {
                if ((flags & RestrictionFlags.MaxInclusive) != 0) {
                    if (value > valueConverter.ToDecimal(restriction.MaxInclusive)) {
                        return new XmlSchemaException(Res.Sch_MaxInclusiveConstraintFailed, string.Empty);
                    }
                }

                if ((flags & RestrictionFlags.MaxExclusive) != 0) {
                    if (value >= valueConverter.ToDecimal(restriction.MaxExclusive)) {
                        return new XmlSchemaException(Res.Sch_MaxExclusiveConstraintFailed, string.Empty);
                    }
                }

                if ((flags & RestrictionFlags.MinInclusive) != 0) {
                    if (value < valueConverter.ToDecimal(restriction.MinInclusive)) {
                        return new XmlSchemaException(Res.Sch_MinInclusiveConstraintFailed, string.Empty);
                    }
                }
                
                if ((flags & RestrictionFlags.MinExclusive) != 0) {
                    if (value <= valueConverter.ToDecimal(restriction.MinExclusive)) {
                        return new XmlSchemaException(Res.Sch_MinExclusiveConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.Enumeration) != 0) {
                    if (!MatchEnumeration(value, restriction.Enumeration, valueConverter)) {
                        return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                    }
                }
                return CheckTotalAndFractionDigits(value, restriction.TotalDigits, restriction.FractionDigits, ((flags & RestrictionFlags.TotalDigits) != 0), ((flags & RestrictionFlags.FractionDigits) != 0));
            }
            return null;
        }
        
        internal override Exception CheckValueFacets(Int64 value, XmlSchemaDatatype datatype) {
            decimal decimalValue = (decimal)value;
            return CheckValueFacets(decimalValue, datatype);
        }

        internal override Exception CheckValueFacets(Int32 value, XmlSchemaDatatype datatype) {
            decimal decimalValue = (decimal)value;
            return CheckValueFacets(decimalValue, datatype);
        }
        internal override Exception CheckValueFacets(Int16 value, XmlSchemaDatatype datatype) {
            decimal decimalValue = (decimal)value;
            return CheckValueFacets(decimalValue, datatype);
        }
        internal override Exception CheckValueFacets(byte value, XmlSchemaDatatype datatype) {
            decimal decimalValue = (decimal)value;
            return CheckValueFacets(decimalValue, datatype);
        }
        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration(datatype.ValueConverter.ToDecimal(value), enumeration, datatype.ValueConverter);
        }

        internal bool MatchEnumeration(decimal value, ArrayList enumeration, XmlValueConverter valueConverter) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (value == valueConverter.ToDecimal(enumeration[i])) {
                    return true;
                }
            }
            return false;
        }
        internal Exception CheckTotalAndFractionDigits(decimal value, int totalDigits, int fractionDigits, bool checkTotal, bool checkFraction) {
            decimal maxValue = FacetsChecker.Power(10, totalDigits) - 1; //(decimal)Math.Pow(10, totalDigits) - 1 ;
            int powerCnt = 0;
            if (value < 0) {
                value = Decimal.Negate(value); //Need to compare maxValue allowed against the absolute value
            }
            while (Decimal.Truncate(value) != value) { //Till it has a fraction
                value = value * 10;
                powerCnt++;
            }
        
            if (checkTotal && (value > maxValue || powerCnt > totalDigits)) {
                return new XmlSchemaException(Res.Sch_TotalDigitsConstraintFailed, string.Empty);
            }
            if (checkFraction && powerCnt > fractionDigits) {
                return new XmlSchemaException(Res.Sch_FractionDigitsConstraintFailed, string.Empty);
            }
            return null;
        }
    }

    
    internal class Numeric2FacetsChecker : FacetsChecker {
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            double doubleValue = datatype.ValueConverter.ToDouble(value);
            return CheckValueFacets(doubleValue, datatype);
        }

        internal override Exception CheckValueFacets(double value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            XmlValueConverter valueConverter = datatype.ValueConverter;

            if ((flags & RestrictionFlags.MaxInclusive) != 0) {
                if (value > valueConverter.ToDouble(restriction.MaxInclusive)) {
                    return new XmlSchemaException(Res.Sch_MaxInclusiveConstraintFailed, string.Empty);
                }
            }
            if ((flags & RestrictionFlags.MaxExclusive) != 0) {
                if (value >= valueConverter.ToDouble(restriction.MaxExclusive)) {
                    return new XmlSchemaException(Res.Sch_MaxExclusiveConstraintFailed, string.Empty);
                }
            }

            if ((flags & RestrictionFlags.MinInclusive) != 0) {
                if (value < (valueConverter.ToDouble(restriction.MinInclusive))) {
                    return new XmlSchemaException(Res.Sch_MinInclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MinExclusive) != 0) {
                if (value <= valueConverter.ToDouble(restriction.MinExclusive)) {
                    return new XmlSchemaException(Res.Sch_MinExclusiveConstraintFailed, string.Empty);
                }
            }
            if ((flags & RestrictionFlags.Enumeration) != 0) {
                if (!MatchEnumeration(value, restriction.Enumeration, valueConverter)) {
                    return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                }
            }
            return null;
        }
        
        internal override Exception CheckValueFacets(float value, XmlSchemaDatatype datatype) {
            double doubleValue = (double)value;
            return CheckValueFacets(doubleValue, datatype);
        }
        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration(datatype.ValueConverter.ToDouble(value), enumeration, datatype.ValueConverter);
        }
        private bool MatchEnumeration(double value, ArrayList enumeration, XmlValueConverter valueConverter) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (value == valueConverter.ToDouble(enumeration[i])) {
                    return true;
                }
            }
            return false;
        }
    }
    
    internal class DurationFacetsChecker: FacetsChecker {

        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            TimeSpan timeSpanValue = (TimeSpan)datatype.ValueConverter.ChangeType(value, typeof(TimeSpan));
            return CheckValueFacets(timeSpanValue, datatype);
        }

        internal override Exception CheckValueFacets(TimeSpan value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;

            if ((flags & RestrictionFlags.MaxInclusive) != 0) {
                if (TimeSpan.Compare(value, (TimeSpan)restriction.MaxInclusive) > 0) {
                    return new XmlSchemaException(Res.Sch_MaxInclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MaxExclusive) != 0) {
                if (TimeSpan.Compare(value, (TimeSpan)restriction.MaxExclusive) >= 0) {
                    return new XmlSchemaException(Res.Sch_MaxExclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MinInclusive) != 0) {
                if (TimeSpan.Compare(value, (TimeSpan)restriction.MinInclusive) < 0) {
                    return new XmlSchemaException(Res.Sch_MinInclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MinExclusive) != 0) {
                if (TimeSpan.Compare(value, (TimeSpan)restriction.MinExclusive) <= 0) {
                    return new XmlSchemaException(Res.Sch_MinExclusiveConstraintFailed, string.Empty);
                }
            }
            if ((flags & RestrictionFlags.Enumeration) != 0) {
                if (!MatchEnumeration(value, restriction.Enumeration)) {
                    return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                }
            }
            return null;
        }
        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration((TimeSpan)value, enumeration);
        }

        private bool MatchEnumeration(TimeSpan value, ArrayList enumeration) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (TimeSpan.Compare(value, (TimeSpan)enumeration[i]) == 0) {
                    return true;
                }
            }
            return false;
        }
    }

    internal class DateTimeFacetsChecker: FacetsChecker {
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            DateTime dateTimeValue = datatype.ValueConverter.ToDateTime(value);
            return CheckValueFacets(dateTimeValue, datatype);
        }

        internal override Exception CheckValueFacets(DateTime value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            
            if ((flags & RestrictionFlags.MaxInclusive) != 0) {
                if (datatype.Compare(value, (DateTime)restriction.MaxInclusive) > 0) {
                    return new XmlSchemaException(Res.Sch_MaxInclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MaxExclusive) != 0) {
                if (datatype.Compare(value, (DateTime)restriction.MaxExclusive) >= 0) {
                    return new XmlSchemaException(Res.Sch_MaxExclusiveConstraintFailed, string.Empty);
                }
            }
            
            if ((flags & RestrictionFlags.MinInclusive) != 0) {
                if (datatype.Compare(value, (DateTime)restriction.MinInclusive) < 0) {
                    return new XmlSchemaException(Res.Sch_MinInclusiveConstraintFailed, string.Empty);
                } 
            }
            
            if ((flags & RestrictionFlags.MinExclusive) != 0) {
                if (datatype.Compare(value, (DateTime)restriction.MinExclusive) <= 0) {
                    return new XmlSchemaException(Res.Sch_MinExclusiveConstraintFailed, string.Empty);
                }
            }
            if ((flags & RestrictionFlags.Enumeration) != 0) {
                if (!MatchEnumeration(value, restriction.Enumeration, datatype)) {
                    return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                }
            }
            return null;
        }

        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration(datatype.ValueConverter.ToDateTime(value), enumeration, datatype);
        }

        private bool MatchEnumeration(DateTime value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (datatype.Compare(value, (DateTime)enumeration[i]) == 0) {
                    return true;
                }
            }
            return false;
        }
    }        

    internal class StringFacetsChecker : FacetsChecker { //All types derived from string & anyURI
        static Regex languagePattern;

        static Regex LanguagePattern {
            get {
                if (languagePattern == null) {
                    Regex langRegex = new Regex("^([a-zA-Z]{1,8})(-[a-zA-Z0-9]{1,8})*$", RegexOptions.None);
                    Interlocked.CompareExchange(ref languagePattern, langRegex, null);
                }
                return languagePattern;
            }
        }
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            string stringValue = datatype.ValueConverter.ToString(value);
            return CheckValueFacets(stringValue, datatype, true);
        }

        internal override Exception CheckValueFacets(string value, XmlSchemaDatatype datatype) {
            return CheckValueFacets(value, datatype, true);
        }

        internal Exception CheckValueFacets(string value, XmlSchemaDatatype datatype, bool verifyUri) {
            //Length, MinLength, MaxLength
            int length = value.Length;
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            Exception exception;
            
            exception = CheckBuiltInFacets(value, datatype.TypeCode, verifyUri);
            if (exception != null) return exception;

            if (flags != 0) {
                if ((flags & RestrictionFlags.Length) != 0) {
                    if (restriction.Length != length) {
                        return new XmlSchemaException(Res.Sch_LengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MinLength) != 0) {
                    if (length < restriction.MinLength) {
                        return new XmlSchemaException(Res.Sch_MinLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MaxLength) != 0) {
                    if (restriction.MaxLength < length) {
                        return new XmlSchemaException(Res.Sch_MaxLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.Enumeration) != 0) {
                    if (!MatchEnumeration(value, restriction.Enumeration, datatype)) {
                        return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                    }
                }
            }
            return null;
        }

        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration(datatype.ValueConverter.ToString(value), enumeration, datatype);
        }

        private bool MatchEnumeration(string value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            if (datatype.TypeCode == XmlTypeCode.AnyUri) {
                for (int i = 0; i < enumeration.Count; ++i) {
                    if (value.Equals(((Uri)enumeration[i]).OriginalString)) {
                        return true;
                    }
                }
            }
            else {
                for (int i = 0; i < enumeration.Count; ++i) {
                    if (value.Equals((string)enumeration[i])) {
                        return true;
                    }
                }
            }
            return false;
        }

        private Exception CheckBuiltInFacets(string s, XmlTypeCode typeCode, bool verifyUri) {
            Exception exception = null;

            switch (typeCode) {

                case XmlTypeCode.AnyUri:
                    if (verifyUri) {
                        Uri uri;
                        exception = XmlConvert.TryToUri(s, out uri);
                    }
                    break;

                case XmlTypeCode.NormalizedString:
                    exception = XmlConvert.TryVerifyNormalizedString(s);
                    break;

                case XmlTypeCode.Token:
                    exception = XmlConvert.TryVerifyTOKEN(s);
                    break;

                case XmlTypeCode.Language:
                    if (s == null || s.Length == 0) {
                        return new XmlSchemaException(Res.Sch_EmptyAttributeValue, string.Empty);
                    }
                    if (!LanguagePattern.IsMatch(s)) {
                        return new XmlSchemaException(Res.Sch_InvalidLanguageId, string.Empty);
                    }
                    break;

                case XmlTypeCode.NmToken:
                    exception = XmlConvert.TryVerifyNMTOKEN(s);
                    break;

                case XmlTypeCode.Name:
                    exception = XmlConvert.TryVerifyName(s);
                    break;

                case XmlTypeCode.NCName:
                case XmlTypeCode.Id:
                case XmlTypeCode.Idref:
                case XmlTypeCode.Entity:
                    exception = XmlConvert.TryVerifyNCName(s);
                    break;
                default:
                    break;
            }
            return exception;
        }
    }
    
    internal class QNameFacetsChecker : FacetsChecker {

        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            XmlQualifiedName qualifiedNameValue = (XmlQualifiedName)datatype.ValueConverter.ChangeType(value, typeof(XmlQualifiedName));
            return CheckValueFacets(qualifiedNameValue, datatype);
        }

        internal override Exception CheckValueFacets(XmlQualifiedName value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            if (flags != 0) { //If there are facets defined
                string strValue = value.ToString();
                int length = strValue.Length;
                if ((flags & RestrictionFlags.Length) != 0) {
                    if (restriction.Length != length) {
                        return new XmlSchemaException(Res.Sch_LengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MinLength) != 0) {
                    if (length < restriction.MinLength) {
                        return new XmlSchemaException(Res.Sch_MinLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MaxLength) != 0) {
                    if (restriction.MaxLength < length) {
                        return new XmlSchemaException(Res.Sch_MaxLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.Enumeration) != 0) {
                    if (!MatchEnumeration(value, restriction.Enumeration)) {
                        return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                    }
                }
            }
            return null;
        }
        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration((XmlQualifiedName)datatype.ValueConverter.ChangeType(value, typeof(XmlQualifiedName)), enumeration);
        }

        private bool MatchEnumeration(XmlQualifiedName value, ArrayList enumeration) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (value.Equals((XmlQualifiedName)enumeration[i])) {
                    return true;
                }
            }
            return false;
        }
    }

    internal class MiscFacetsChecker : FacetsChecker { //For bool, anySimpleType
    }

    internal class BinaryFacetsChecker : FacetsChecker { //hexBinary & Base64Binary
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            byte[] byteArrayValue = (byte[])value;
            return CheckValueFacets(byteArrayValue, datatype);
        }

        internal override Exception CheckValueFacets(byte[] value, XmlSchemaDatatype datatype) {
            //Length, MinLength, MaxLength
            RestrictionFacets restriction = datatype.Restriction;
            int length = value.Length;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            if (flags != 0) { //if it has facets defined
                if ((flags & RestrictionFlags.Length) != 0) {
                    if (restriction.Length != length) {
                        return new XmlSchemaException(Res.Sch_LengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MinLength) != 0) {
                    if (length < restriction.MinLength) {
                        return new XmlSchemaException(Res.Sch_MinLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.MaxLength) != 0) {
                    if (restriction.MaxLength < length) {
                        return new XmlSchemaException(Res.Sch_MaxLengthConstraintFailed, string.Empty);
                    }
                }
                if ((flags & RestrictionFlags.Enumeration) != 0) {
                    if (!MatchEnumeration(value, restriction.Enumeration, datatype)) {
                        return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                    }
                }
            }
            return null;
        }
        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            return MatchEnumeration((byte[])value, enumeration, datatype);
        }

        private bool MatchEnumeration(byte[] value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (datatype.Compare(value, (byte[])enumeration[i]) == 0) {
                    return true;
                }
            }
            return false;
        }
    }
    
    internal class ListFacetsChecker : FacetsChecker {
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            //Check for facets allowed on lists - Length, MinLength, MaxLength
            Array values = value as Array;
            Debug.Assert(values != null);

            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            
            if ((flags & (RestrictionFlags.Length|RestrictionFlags.MinLength|RestrictionFlags.MaxLength)) != 0) {
                int length = values.Length;
                if ((flags & RestrictionFlags.Length) != 0) {
                    if (restriction.Length != length) {
                        return new XmlSchemaException(Res.Sch_LengthConstraintFailed, string.Empty);
                    }
                }

                if ((flags & RestrictionFlags.MinLength) != 0) {
                    if (length < restriction.MinLength) {
                        return new XmlSchemaException(Res.Sch_MinLengthConstraintFailed, string.Empty);
                    }
                }

                if ((flags & RestrictionFlags.MaxLength) != 0) {
                    if (restriction.MaxLength < length) {
                        return new XmlSchemaException(Res.Sch_MaxLengthConstraintFailed, string.Empty);
                    }
                }
            }
            if ((flags & RestrictionFlags.Enumeration) != 0) {
                if (!MatchEnumeration(value, restriction.Enumeration, datatype)) {
                    return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                }
            }
            return null;
        }

        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (datatype.Compare(value, enumeration[i]) == 0) {
                    return true;
                }
            }
            return false;
        }
    }

    internal class UnionFacetsChecker : FacetsChecker {
        
        internal override Exception CheckValueFacets(object value, XmlSchemaDatatype datatype) {
            RestrictionFacets restriction = datatype.Restriction;
            RestrictionFlags flags = restriction != null ? restriction.Flags : 0;
            
            if ((flags & RestrictionFlags.Enumeration) != 0) {
                if (!MatchEnumeration(value, restriction.Enumeration, datatype)) {
                    return new XmlSchemaException(Res.Sch_EnumerationConstraintFailed, string.Empty);
                }
            }
            return null;
        }

        internal override bool MatchEnumeration(object value, ArrayList enumeration, XmlSchemaDatatype datatype) {
            for (int i = 0; i < enumeration.Count; ++i) {
                if (datatype.Compare(value, enumeration[i]) == 0) { //Compare on Datatype_union will compare two XsdSimpleValue
                    return true;
                }
            }
            return false;
        }
    }
}