#region MIT license
// 
// MIT license
//
// Copyright (c) 2007-2008 Jiri Moudry, Pascal Craponne
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// 
#endregion
using System.Collections.Generic;
using System.IO;
using System.Reflection;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;

namespace DbLinq.Schema.Dbml
{
    /// <summary>
    /// Serializes DBML
    /// </summary>
#if !MONO_STRICT
    public
#endif
    static class DbmlSerializer
    {
        private class ValidationException : XmlSchemaValidationException
        {
            public ValidationException(IList<string> errors)
            {
                Data["Errors"] = errors;
            }
        }

        /// <summary>
        /// Opens the XML stream, given an XSD validation.
        /// </summary>
        /// <param name="xmlStream">The XML stream.</param>
        /// <param name="xsdStream">The XSD stream.</param>
        /// <param name="validationErrors">The validation errors.</param>
        /// <returns></returns>
        private static XmlReader OpenXml(Stream xmlStream, Stream xsdStream, ICollection<string> validationErrors)
        {
            validationErrors.Clear();

            var xmlReaderSettings = new XmlReaderSettings();
            xmlReaderSettings.Schemas.Add(null, XmlReader.Create(xsdStream));
            xmlReaderSettings.ValidationType = ValidationType.Schema;
            xmlReaderSettings.ValidationEventHandler += ((sender, e) => validationErrors.Add(e.Message));
            var xmlValidator = XmlReader.Create(xmlStream, xmlReaderSettings);
            return xmlValidator;
        }

        /// <summary>
        /// Opens the XSD file.
        /// </summary>
        /// <returns></returns>
        private static Stream OpenXsd()
        {
            return Assembly.GetExecutingAssembly().GetManifestResourceStream(typeof(DbmlSerializer), "DbmlSchema.xsd");
        }

        /// <summary>
        /// Checks if validation contains error.
        /// </summary>
        /// <param name="validationErrors">The validation errors.</param>
        private static void CheckValidation(IList<string> validationErrors)
        {
            if (validationErrors.Count > 0)
            {
                throw new ValidationException(validationErrors);
            }
        }

        /// <summary>
        /// Reads the specified XML stream for a Database schema.
        /// </summary>
        /// <param name="xmlStream">The XML stream.</param>
        /// <param name="validationErrors">The validation errors.</param>
        /// <returns></returns>
        public static Database Read(Stream xmlStream, IList<string> validationErrors)
        {
            using (Stream xsdStream = OpenXsd())
            using (XmlReader xmlReader = OpenXml(xmlStream, xsdStream, validationErrors))
            {
                var xmlSerializer = new DatabaseSerializer();
                var dbml = (Database)xmlSerializer.Deserialize(xmlReader);
                return dbml;
            }
        }

        /// <summary>
        /// Reads the specified XML stream for a DBML schema.
        /// </summary>
        /// <param name="xmlStream">The XML stream.</param>
        /// <returns></returns>
        public static Database Read(Stream xmlStream)
        {
            var validationErrors = new List<string>();
            var dbml = Read(xmlStream, validationErrors);
            CheckValidation(validationErrors);
            return dbml;
        }

        /// <summary>
        /// Writes the specified XML stream.
        /// </summary>
        /// <param name="xmlStream">The XML stream.</param>
        /// <param name="dbml">The DBML.</param>
        public static void Write(Stream xmlStream, Database dbml)
        {
            var xmlSerializer = new DatabaseSerializer();
            xmlSerializer.Serialize(xmlStream, dbml);
        }
    }
}
