//-----------------------------------------------------------------------
// <copyright file="DupuitStateFiler.cs" company="Deltares">
//  Copyright (c) 2011 Deltares. All rights reserved.
// </copyright>
// <author>B.S.T. The</author>
// <email>tom.the@deltares.nl</email>
// <date>20-12-2011</date>
// <summary>Load and save state for DikeFlow calculation</summary>
//-----------------------------------------------------------------------
using System.IO;
using Deltares.Standard.IO;

namespace Deltares.Dam.Data
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;

    public class DupuitStateFilerException : ApplicationException
    {
        public DupuitStateFilerException(string message)
            : base(message)
        {
        }
    }

    public class DupuitStateFiler
    {
        public const string initialStateExtension = ".C000";
        public const string endStateExtension = ".CEND";

        static private void ThrowIfPathNotExists(string path)
        {
            if (!Directory.Exists(path))
            {
                throw new DupuitStateFilerException(String.Format("Path '{0}' not found", path));
            }
        }

        static private void CreateDirectoryIfNotExists(string pathName)
        {
            if (!Directory.Exists(pathName))
            {
                Directory.CreateDirectory(pathName);
            }
        }


        static public void SaveState(string sourcePath, string destinationPath, string extension)
        {
            ThrowIfPathNotExists(sourcePath);
            CreateDirectoryIfNotExists(destinationPath);
            CopyFiles(sourcePath, destinationPath, extension, endStateExtension);
        }

        private static void CopyFiles(string sourcePath, string destinationPath, string sourceExtension, string destinationExtension)
        {
            string[] fileEntries = Directory.GetFiles(sourcePath, "*" + sourceExtension);
            foreach (string fileEntry in fileEntries)
            {
                string sourceFilename = Path.GetFileName(fileEntry);
                string destinationFilename = Path.Combine(destinationPath, Path.ChangeExtension(sourceFilename, destinationExtension));
                if (File.Exists(destinationFilename))
                {
                    File.Delete(destinationFilename);
                }
                File.Copy(fileEntry, destinationFilename);
            }
        }

        static public void LoadState(string sourcePath, string destinationPath, string stateExtension)
        {
            ThrowIfPathNotExists(sourcePath);
            CreateDirectoryIfNotExists(destinationPath);
            CopyFiles(sourcePath, destinationPath, stateExtension, initialStateExtension);
        }

        /// <summary>
        /// Gets the last state extension; this is the extension with the highest number
        /// </summary>
        /// <param name="sourcePath">The source path.</param>
        /// <param name="extensionMask">The extension mask.</param>
        /// <returns></returns>
        static public string GetLastStateExtension(string sourcePath, string fileStateMask)
        {
            string[] fileEntries = Directory.GetFiles(sourcePath, fileStateMask);
            List<string> fileEntriesList = fileEntries.ToList();
            fileEntriesList.Sort();
            string extension = Path.GetExtension(fileEntriesList.Last());
            return extension;
        }
    }
}