//Copyright (c) Microsoft Corporation.  All rights reserved.



namespace Xml.Schema.Linq.Fxt

{

    using System;

    using System.Linq;

    using System.Xml;

    using System.Xml.Schema;

    using System.Collections.Generic;



    public static class XmlSchemaQueryExtensions

    {



        public static bool DefinesXsdType(this XmlSchemaSet schemas, XmlQualifiedName name)

        {

            return schemas.GlobalXsdTypes().QNames().Contains(name);

        }



        public static bool DefinesXsdElement(this XmlSchemaSet schemas, XmlQualifiedName name)

        {

            return schemas.GlobalXsdElements().QNames().Contains(name);

        }



        public static bool DefinesXsdAttribute(this XmlSchemaSet schemas, XmlQualifiedName name)

        {

            return schemas.GlobalXsdAttributes().QNames().Contains(name);

        }



        public static XmlQualifiedName RootType(this XmlSchemaSet schemas, XmlQualifiedName name)

        {

            var ct = schemas.GlobalTypes[name] as XmlSchemaComplexType;

            if (ct==null)

                return null;

            if (ct.BaseXmlSchemaType.TypeCode == XmlTypeCode.Item)

                return name;

            return schemas.RootType(ct.BaseXmlSchemaType.QualifiedName);

        }



        public static XmlQualifiedName RootElement(this XmlSchemaSet schemas, XmlQualifiedName name)

        {

            var el = schemas.GlobalElements[name] as XmlSchemaElement;

            var bname = el.SubstitutionGroup;

            if (bname.IsEmpty)

                return name;

            return schemas.RootElement(bname);

        }



        public static bool IsDerivedComplexType(this XmlSchemaType ty)

        {

            var ct = ty as XmlSchemaComplexType;

            if (ct!=null)

                return (ct.ContentModel as XmlSchemaComplexContent) != null;

            return false;

        }



        public static bool IsGlobal(this XmlSchemaElement el)

        {

            return el.Parent is XmlSchema;

        }



        public static bool IsLocal(this XmlSchemaElement el)

        {

            return !el.IsGlobal();

        }



        public static XmlSchema XmlSchema(this XmlSchemaObject o)

        {

            if (o is XmlSchema) return (o as XmlSchema);

            else return o.Parent.XmlSchema();

        }



        public static IEnumerable<XmlSchema> XmlSchemas(this XmlSchemaSet set)

        {

            foreach (XmlSchema x in set.Schemas())

                yield return x;

        }



        public static IEnumerable<XmlSchemaType> GlobalXsdTypes(this XmlSchemaSet set)

        {

            foreach (var x in set.XmlSchemas())

                foreach (var y in x.GlobalXsdTypes())

                    yield return y;

        }



        public static IEnumerable<XmlSchemaType> AllXsdTypes(this XmlSchemaSet set)

        {

            return Enumerable.Union(

                set.GlobalXsdTypes(),

                set.AnonymousXsdTypes());

        }



        public static IEnumerable<XmlSchemaType> GlobalXsdTypes(this XmlSchema schema)

        {

            foreach (XmlSchemaType x in schema.SchemaTypes.Values)

                yield return x;

        }



        public static IEnumerable<XmlSchemaType> AnonymousXsdTypes(this XmlSchemaSet set)

        {

            return

                from gel in set.AllXsdElements()

                where gel.SchemaType != null

                select gel.SchemaType;

        }



        public static IEnumerable<XmlQualifiedName> QNames(this IEnumerable<XmlSchemaType> types)

        {

            return types.Select(x => x.QualifiedName);

        }



        public static IEnumerable<XmlSchemaElement> AllXsdElements(this XmlSchemaSet set)

        {

            return Enumerable.Union(

                set.GlobalXsdElements(),

                set.LocalXsdElements());

        }



        public static IEnumerable<XmlSchemaElement> GlobalXsdElements(this XmlSchemaSet set)

        {

            foreach (var x in set.XmlSchemas())

                foreach (var y in x.GlobalXsdElements())

                    yield return y;

        }



        public static IEnumerable<XmlSchemaElement> GlobalXsdElements(this XmlSchema schema)

        {

            foreach (XmlSchemaElement x in schema.Elements.Values)

                yield return x;

        }



        public static IEnumerable<XmlSchemaAttribute> GlobalXsdAttributes(this XmlSchemaSet set)

        {

            foreach (var x in set.XmlSchemas())

                foreach (var y in x.GlobalXsdAttributes())

                    yield return y;

        }



        public static IEnumerable<XmlSchemaAttribute> GlobalXsdAttributes(this XmlSchema schema)

        {

            foreach (XmlSchemaAttribute x in schema.Attributes.Values)

                yield return x;

        }



        public static IEnumerable<XmlQualifiedName> QNames(this IEnumerable<XmlSchemaElement> els)

        {

            return els.Select(x => x.QualifiedName);

        }



        public static IEnumerable<XmlQualifiedName> QNames(this IEnumerable<XmlSchemaAttribute> els)

        {

            return els.Select(x => x.QualifiedName);

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchemaSet set)

        {

            foreach (var x in set.XmlSchemas())

                foreach (var y in x.LocalXsdElements())

                    yield return y;

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchema schema)

        {

            foreach (XmlSchemaElement x in schema.Elements.Values)

                foreach (var y in x.LocalXsdElements())

                    yield return y;



            foreach (XmlSchemaType x in schema.SchemaTypes.Values)

                foreach (var y in x.LocalXsdElements())

                    yield return y;



            foreach (XmlSchemaGroup x in schema.Groups.Values)

                foreach (var y in x.LocalXsdElements())

                    yield return y;            

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchemaElement el)

        {

            return el.SchemaType.LocalXsdElements();

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchemaType ty)

        {

            var ct = ty as XmlSchemaComplexType;

            if (ct==null) yield break;

            if (ct.ContentModel==null)

                foreach (var x in ct.Particle.LocalXsdElements())

                    yield return x;

            else

            {

                var cc = ct.ContentModel as XmlSchemaComplexContent;

                if (cc==null) yield break;

                var ext = cc.Content as XmlSchemaComplexContentExtension;

                if (ext==null) yield break;

                foreach (var x in ext.Particle.LocalXsdElements())

                    yield return x;

            }

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchemaGroup gr)

        {

            return gr.Particle.LocalXsdElements();

        }



        public static IEnumerable<XmlSchemaElement> LocalXsdElements(this XmlSchemaParticle pa)

        {

            if (pa==null) yield break;



            var grp = pa as XmlSchemaGroupBase;

            if (grp!=null)

            {

                foreach (XmlSchemaParticle x in grp.Items)

                    foreach (var y in x.LocalXsdElements())

                        yield return y;

                yield break;

            }



            var el = pa as XmlSchemaElement;

            if (el!=null)

            {

                yield return el;

                foreach (var x in el.SchemaType.LocalXsdElements())

                    yield return x;

                yield break;

            }            

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchemaSet set)

        {

            foreach (var x in set.XmlSchemas())

                foreach (var y in x.LocalXsdAttributes())

                    yield return y;

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchema schema)

        {

            foreach (XmlSchemaElement x in schema.Elements.Values)

                foreach (var y in x.LocalXsdAttributes())

                    yield return y;



            foreach (XmlSchemaType x in schema.SchemaTypes.Values)

                foreach (var y in x.LocalXsdAttributes())

                    yield return y;



            foreach (XmlSchemaGroup x in schema.Groups.Values)

                foreach (var y in x.LocalXsdAttributes())

                    yield return y;            

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchemaElement el)

        {

            return el.SchemaType.LocalXsdAttributes();

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchemaType ty)

        {

            var ct = ty as XmlSchemaComplexType;

            if (ct==null) yield break;

            foreach (XmlSchemaAttribute x in ct.Attributes)

                yield return x;

            if (ct.ContentModel==null)

                foreach (var x in ct.Particle.LocalXsdAttributes())

                    yield return x;

            else

            {

                var cc = ct.ContentModel as XmlSchemaComplexContent;

                if (cc==null) yield break;

                var ext = cc.Content as XmlSchemaComplexContentExtension;

                if (ext==null) yield break;

                foreach (XmlSchemaAttribute x in ext.Attributes)

                    yield return x;

                foreach (var x in ext.Particle.LocalXsdAttributes())

                    yield return x;

            }

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchemaGroup gr)

        {

            return gr.Particle.LocalXsdAttributes();

        }



        public static IEnumerable<XmlSchemaAttribute> LocalXsdAttributes(this XmlSchemaParticle pa)

        {

            if (pa==null) yield break;



            var grp = pa as XmlSchemaGroupBase;

            if (grp!=null)

            {

                foreach (XmlSchemaParticle x in grp.Items)

                    foreach (var y in x.LocalXsdAttributes())

                        yield return y;

                yield break;

            }



            var el = pa as XmlSchemaElement;

            if (el!=null)

            {

                foreach (var x in el.SchemaType.LocalXsdAttributes())

                    yield return x;

                yield break;

            }            

        }



        public static IEnumerable<XmlSchemaAttribute> XsdAttributesInScope(this XmlSchemaElement el) {

            return el.SchemaType.XsdAttributesInScope();

        }



        public static IEnumerable<XmlSchemaAttribute> XsdAttributesInScope(this XmlSchemaType ty) {

            if (ty==null) yield break;

            var ct = ty as XmlSchemaComplexType;

            if (ct==null) yield break;

            foreach (XmlSchemaAttribute x in ct.Attributes)

                yield return x;

            if (ct.ContentModel!=null) {

                var cc = ct.ContentModel as XmlSchemaComplexContent;

                if (cc==null) yield break;

                var ext = cc.Content as XmlSchemaComplexContentExtension;

                if (ext==null) yield break;

                foreach (XmlSchemaAttribute x in ext.Attributes)

                    yield return x;

            }

        }

    }

}