/*
  * The contents of this file are subject to the Mozilla Public
  * License Version 1.1 (the "License"); you may not use this
  * file except in compliance with the License. You may obtain
  * a copy of the License at http://www.mozilla.org/MPL/
  *
  * Software distributed under the License is distributed on an
  * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
  * or implied. See the License for the specific language governing
  * rights and limitations under the License.
  *
  *
  * The Original Code is .NET RASP toolkit.
  *
  * The Initial Developer of the Original Code is Accenture and Avanade.
  * Portions created by Accenture and Avanade are Copyright (C) 2009
  * Danish National IT and Telecom Agency (http://www.itst.dk). 
  * All Rights Reserved.
  *
  * Contributor(s):
  *   Gert Sylvest, Avanade
  *   Jesper Jensen, Avanade
  *   Ramzi Fadel, Avanade
  *   Patrik Johansson, Accenture
  *   Dennis Søgaard, Accenture
  *   Christian Pedersen, Accenture
  *   Martin Bentzen, Accenture
  *   Mikkel Hippe Brun, ITST
  *   Finn Hartmann Jordal, ITST
  *   Christian Lanng, ITST
  *
  */

using System;
using System.Collections.Generic;
using System.Text;
using System.Resources;

namespace dk.gov.oiosi.exception.MessageStore {
    /// <summary>
    /// Used to handle the resourcefile in the MessageStore custom exceptions
    /// </summary>
    public class ResourceFileExceptionMessageStore : IExceptionMessageStore {
        private ResourceManager internalErrorMessages = new ResourceManager(typeof(ErrorMessages));

        #region IExceptionHandle Members

        /// <summary>
        /// Returns an exception message as string
        /// </summary>
        /// <param name="resources">The list of resource managers to involve</param>
        /// <param name="exceptionType">The type of the exception</param>
        /// <param name="keywords">Keyword pairs to use</param>
        /// <returns>Returns the message string</returns>
        public string GetExceptionMessage(IEnumerable<ResourceManager> resources, Type exceptionType, Dictionary<string, string> keywords) {
            List<ResourceManager> allResources = new List<ResourceManager>(resources);
            allResources.Add(internalErrorMessages);
            string unformatedErrorMessage = GetUnformatedExceptionMessage(allResources, exceptionType, true);
            string formatedErrorMessage = GetFormatedExceptionMessage(keywords, unformatedErrorMessage, exceptionType);
            return formatedErrorMessage;
        }

        /// <summary>
        /// Try to get the exception message. It does not throw any exceptions if 
        /// it fails but returns a boolean whether it succeeded or not.
        /// </summary>
        /// <param name="resources"></param>
        /// <param name="exceptionType"></param>
        /// <param name="keywords"></param>
        /// <param name="exceptionMessage"></param>
        /// <returns></returns>
        public bool TryGetExternalExceptionMessage(IEnumerable<ResourceManager> resources, Type exceptionType, Dictionary<string, string> keywords, out string exceptionMessage) {
            exceptionMessage = null;
            string unformatedErrorMessage = GetUnformatedExceptionMessage(resources, exceptionType, false);
            if (unformatedErrorMessage == null) return false;
            string formatedErrorMessage = GetFormatedExceptionMessage(keywords, unformatedErrorMessage, exceptionType);
            exceptionMessage = formatedErrorMessage;
            return true;
        }

        #endregion
        
        private string GetUnformatedExceptionMessage(IEnumerable<ResourceManager> resources ,Type exceptionType, bool throwException) {
            string exceptionTypeString = exceptionType.ToString();
            string key = exceptionTypeString.Replace('.', '_');
            int index = key.IndexOf('`');
            if (index > -1) key = key.Remove(index);
            string unformatedErrorMessage = null;
            foreach (ResourceManager resourceManager in resources) {
                unformatedErrorMessage = resourceManager.GetString(key);
                if (unformatedErrorMessage != null) break; 
            }
            if (unformatedErrorMessage == null && throwException) throw new MessageToExceptionNotFoundException("Der kunne ikke findes en fejlbesked til '" + exceptionType.ToString() + "'");
            return unformatedErrorMessage;
        }

        private string GetFormatedExceptionMessage(Dictionary<string, string> keywords, string unformatedErrorMessage, Type exceptionType) {
            char[] charArray = unformatedErrorMessage.ToCharArray();
            string keyword = "";
            string fixedString = "";
            bool partOfKeyword = false;
            foreach (char character in charArray) {
                switch (character) {
                    case '[':
                        //This exception cannot be handled by the same way as the standard exception
                        if (partOfKeyword) throw new DoubleStartOfKeywordException("Der dobbelt start af keyword i beskeden : '" + unformatedErrorMessage + "'");
                        partOfKeyword = true;
                        continue;
                    case ']':
                        //This exception cannot be handled by the same way as the standard exception
                        if (!partOfKeyword) throw new UnexpectedEndOfKeywordException("Der er et uventet afslutning af keyword i beskeden : '" + unformatedErrorMessage + "'");
                        string foundKeyword = ""; 
                        bool keywordExits = keywords.TryGetValue(keyword, out foundKeyword);
                        //This exception cannot be handled by the same way as the standard exception
                        if (!keywordExits) throw new KeywordNotFoundException("Keyword '" + keyword + "' ikke fundet i de medsendte keywords til excpetion '" + exceptionType.ToString() + "'");
                        fixedString += foundKeyword;
                        keyword = "";
                        partOfKeyword = false;
                        continue;
                    default:
                        break;
                }
                if (partOfKeyword) {
                    keyword += character;
                }
                else {
                    fixedString += character;
                }
            }
            return fixedString;
        }
    }
}
