// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Text;
using System.Xml;
 
namespace System.Xml.Schema
{
    public abstract class XmlSchemaDatatype
    {
        public abstract Type ValueType { get; }
 
        public abstract XmlTokenizedType TokenizedType { get; }
 
        public abstract object ParseValue(string s, XmlNameTable? nameTable, IXmlNamespaceResolver? nsmgr);
 
        public virtual XmlSchemaDatatypeVariety Variety { get { return XmlSchemaDatatypeVariety.Atomic; } }
 
        internal abstract Type ListValueType { get; }
 
        internal XmlSchemaDatatype() { }
 
        public virtual object ChangeType(object value, Type targetType)
        {
            ArgumentNullException.ThrowIfNull(value);
            ArgumentNullException.ThrowIfNull(targetType);
 
            return ValueConverter.ChangeType(value, targetType);
        }
 
        public virtual object ChangeType(object value, Type targetType, IXmlNamespaceResolver namespaceResolver)
        {
            ArgumentNullException.ThrowIfNull(value);
            ArgumentNullException.ThrowIfNull(targetType);
            ArgumentNullException.ThrowIfNull(namespaceResolver);
 
            return ValueConverter.ChangeType(value, targetType, namespaceResolver);
        }
 
        public virtual XmlTypeCode TypeCode { get { return XmlTypeCode.None; } }
 
        public virtual bool IsDerivedFrom(XmlSchemaDatatype datatype)
        {
            return false;
        }
 
        internal abstract bool HasLexicalFacets { get; }
 
        internal abstract bool HasValueFacets { get; }
 
        internal abstract XmlValueConverter ValueConverter { get; }
 
        internal abstract RestrictionFacets? Restriction { get; set; }
 
        internal abstract int Compare(object value1, object value2);
 
        internal abstract object ParseValue(string s, XmlNameTable? nameTable, IXmlNamespaceResolver? nsmgr, bool createAtomicValue);
 
        internal abstract Exception? TryParseValue(string s, XmlNameTable? nameTable, IXmlNamespaceResolver? nsmgr, out object? typedValue);
 
        internal abstract Exception? TryParseValue(object value, XmlNameTable? nameTable, IXmlNamespaceResolver? namespaceResolver, out object? typedValue);
 
        internal abstract FacetsChecker FacetsChecker { get; }
 
        internal abstract XmlSchemaWhiteSpace BuiltInWhitespaceFacet { get; }
 
        internal abstract XmlSchemaDatatype DeriveByRestriction(XmlSchemaObjectCollection facets, XmlNameTable nameTable, XmlSchemaType schemaType);
 
        internal abstract XmlSchemaDatatype DeriveByList(XmlSchemaType? schemaType);
 
        internal abstract void VerifySchemaValid(XmlSchemaObjectTable notations, XmlSchemaObject caller);
 
        internal abstract bool IsEqual(object o1, object o2);
 
        internal abstract bool IsComparable(XmlSchemaDatatype dtype);
 
        //Error message helper
        internal string TypeCodeString
        {
            get
            {
                string typeCodeString = string.Empty;
                XmlTypeCode typeCode = this.TypeCode;
                switch (this.Variety)
                {
                    case XmlSchemaDatatypeVariety.List:
                        if (typeCode == XmlTypeCode.AnyAtomicType)
                        { //List of union
                            typeCodeString = "List of Union";
                        }
                        else
                        {
                            typeCodeString = $"List of {TypeCodeToString(typeCode)}";
                        }
                        break;
 
                    case XmlSchemaDatatypeVariety.Union:
                        typeCodeString = "Union";
                        break;
 
                    case XmlSchemaDatatypeVariety.Atomic:
                        if (typeCode == XmlTypeCode.AnyAtomicType)
                        {
                            typeCodeString = "anySimpleType";
                        }
                        else
                        {
                            typeCodeString = TypeCodeToString(typeCode);
                        }
                        break;
                }
                return typeCodeString;
            }
        }
 
        internal static string TypeCodeToString(XmlTypeCode typeCode) =>
            typeCode switch
            {
                XmlTypeCode.None => "None",
                XmlTypeCode.Item => "AnyType",
                XmlTypeCode.AnyAtomicType => "AnyAtomicType",
                XmlTypeCode.String => "String",
                XmlTypeCode.Boolean => "Boolean",
                XmlTypeCode.Decimal => "Decimal",
                XmlTypeCode.Float => "Float",
                XmlTypeCode.Double => "Double",
                XmlTypeCode.Duration => "Duration",
                XmlTypeCode.DateTime => "DateTime",
                XmlTypeCode.Time => "Time",
                XmlTypeCode.Date => "Date",
                XmlTypeCode.GYearMonth => "GYearMonth",
                XmlTypeCode.GYear => "GYear",
                XmlTypeCode.GMonthDay => "GMonthDay",
                XmlTypeCode.GDay => "GDay",
                XmlTypeCode.GMonth => "GMonth",
                XmlTypeCode.HexBinary => "HexBinary",
                XmlTypeCode.Base64Binary => "Base64Binary",
                XmlTypeCode.AnyUri => "AnyUri",
                XmlTypeCode.QName => "QName",
                XmlTypeCode.Notation => "Notation",
                XmlTypeCode.NormalizedString => "NormalizedString",
                XmlTypeCode.Token => "Token",
                XmlTypeCode.Language => "Language",
                XmlTypeCode.NmToken => "NmToken",
                XmlTypeCode.Name => "Name",
                XmlTypeCode.NCName => "NCName",
                XmlTypeCode.Id => "Id",
                XmlTypeCode.Idref => "Idref",
                XmlTypeCode.Entity => "Entity",
                XmlTypeCode.Integer => "Integer",
                XmlTypeCode.NonPositiveInteger => "NonPositiveInteger",
                XmlTypeCode.NegativeInteger => "NegativeInteger",
                XmlTypeCode.Long => "Long",
                XmlTypeCode.Int => "Int",
                XmlTypeCode.Short => "Short",
                XmlTypeCode.Byte => "Byte",
                XmlTypeCode.NonNegativeInteger => "NonNegativeInteger",
                XmlTypeCode.UnsignedLong => "UnsignedLong",
                XmlTypeCode.UnsignedInt => "UnsignedInt",
                XmlTypeCode.UnsignedShort => "UnsignedShort",
                XmlTypeCode.UnsignedByte => "UnsignedByte",
                XmlTypeCode.PositiveInteger => "PositiveInteger",
 
                _ => typeCode.ToString(),
            };
 
        internal static string ConcatenatedToString(object value)
        {
            Type t = value.GetType();
            string stringValue = string.Empty;
            if (t == typeof(IEnumerable) && t != typeof(string))
            {
                StringBuilder bldr = new StringBuilder();
                IEnumerator enumerator = (value as IEnumerable)!.GetEnumerator();
                if (enumerator.MoveNext())
                {
                    bldr.Append('{');
                    object cur = enumerator.Current!;
                    if (cur is IFormattable)
                    {
                        bldr.Append(((IFormattable)cur).ToString("", CultureInfo.InvariantCulture));
                    }
                    else
                    {
                        bldr.Append(cur.ToString());
                    }
                    while (enumerator.MoveNext())
                    {
                        bldr.Append(" , ");
                        cur = enumerator.Current!;
                        if (cur is IFormattable)
                        {
                            bldr.Append(((IFormattable)cur).ToString("", CultureInfo.InvariantCulture));
                        }
                        else
                        {
                            bldr.Append(cur.ToString());
                        }
                    }
                    bldr.Append('}');
                    stringValue = bldr.ToString();
                }
            }
            else if (value is IFormattable)
            {
                stringValue = ((IFormattable)value).ToString("", CultureInfo.InvariantCulture);
            }
            else
            {
                stringValue = value.ToString()!;
            }
            return stringValue;
        }
 
        internal static XmlSchemaDatatype? FromXmlTokenizedType(XmlTokenizedType token)
        {
            return DatatypeImplementation.FromXmlTokenizedType(token);
        }
 
        internal static XmlSchemaDatatype? FromXmlTokenizedTypeXsd(XmlTokenizedType token)
        {
            return DatatypeImplementation.FromXmlTokenizedTypeXsd(token);
        }
 
        internal static XmlSchemaDatatype? FromXdrName(string name)
        {
            return DatatypeImplementation.FromXdrName(name);
        }
 
        internal static XmlSchemaDatatype DeriveByUnion(XmlSchemaSimpleType[] types, XmlSchemaType schemaType)
        {
            return DatatypeImplementation.DeriveByUnion(types, schemaType);
        }
 
        internal static string XdrCanonizeUri(string uri, XmlNameTable nameTable, SchemaNames schemaNames)
        {
            string canonicalUri;
            int offset = 5;
            bool convert = false;
 
            if (uri.Length > 5 && uri.StartsWith("uuid:", StringComparison.Ordinal))
            {
                convert = true;
            }
            else if (uri.Length > 9 && uri.StartsWith("urn:uuid:", StringComparison.Ordinal))
            {
                convert = true;
                offset = 9;
            }
 
            if (convert)
            {
                canonicalUri = nameTable.Add(string.Concat(uri.AsSpan(0, offset), uri.Substring(offset).ToUpperInvariant()));
            }
            else
            {
                canonicalUri = uri;
            }
 
            if (
                Ref.Equal(schemaNames.NsDataTypeAlias, canonicalUri) ||
                Ref.Equal(schemaNames.NsDataTypeOld, canonicalUri)
            )
            {
                canonicalUri = schemaNames.NsDataType;
            }
            else if (Ref.Equal(schemaNames.NsXdrAlias, canonicalUri))
            {
                canonicalUri = schemaNames.NsXdr;
            }
 
            return canonicalUri;
        }
    }
}