#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2016 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;

namespace HeuristicLab.Problems.Instances.PFSP
{
    public class FSSPTAILIBParser
    {
        public string Name { get; set; }
        public string Description { get; set; }
        public int Jobs { get; set; }
        public int Machines { get; set; }
        public double[,] ProcessingTimes { get; set; }

        public int[] BestKnownSchedule { get; set; }
        public int BestKnownQuality { get; set; }

        public FSSPTAILIBParser()
        {
            Reset();
        }

        public void Reset()
        {
            Name = Description = String.Empty;
            Jobs = Machines = BestKnownQuality = 0;
            ProcessingTimes = null;
            BestKnownSchedule = null;
        }

        public void Parse(string file)
        {
            using (Stream stream = new FileStream(file, FileMode.Open, FileAccess.Read))
            {
                Parse(stream);
            }
        }

        public void Export(string file)
        {
            using (Stream stream = new FileStream(file, FileMode.Create, FileAccess.Write))
            {
                Export(stream);
            }
        }

        /// <summary>
        /// Reads from the given stream data which is expected to be in the JSSP ORLIB format.
        /// </summary>
        /// <remarks>
        /// The stream is not closed or disposed. The caller has to take care of that.
        /// </remarks>
        /// <param name="stream">The stream to read data from.</param>
        public void Parse(Stream stream)
        {
            using (var reader = new StreamReader(stream, Encoding.UTF8, true, 4092, true))
            {
                Name = reader.ReadLine().Trim();
                Description = reader.ReadLine().Trim();
                var delim = new char[] { ' ', '\t' };

                var info = reader.ReadLine().Split(delim, StringSplitOptions.RemoveEmptyEntries);
                Jobs = int.Parse(info[0]);
                Machines = int.Parse(info[1]);
                var bestKnownQuality = reader.ReadLine().Trim();
                BestKnownQuality = int.Parse(bestKnownQuality);
                ProcessingTimes = new double[Machines, Jobs];

                for (int k = 0; k < Machines; k++)
                {
                    if (reader.EndOfStream) throw new InvalidDataException("Unexpected End of Stream.");
                    var valLine = reader.ReadLine();
                    while (String.IsNullOrWhiteSpace(valLine)) valLine = reader.ReadLine();
                    var vals = valLine.Split(delim, StringSplitOptions.RemoveEmptyEntries);


                    for (int i = 0; i < Jobs; i++)
                    {
                        ProcessingTimes[k, i] = double.Parse(vals[i], CultureInfo.InvariantCulture.NumberFormat);
                    }
                }

                while (!reader.EndOfStream)
                {
                    var vals = reader.ReadLine().Split(delim, StringSplitOptions.RemoveEmptyEntries);
                    if (vals.Count() == Jobs) { BestKnownSchedule = vals.Select(val => Int32.Parse(val)).ToArray(); }
                }
            }
        }

        /// <summary>
        /// Writes to the given stream data which is expected to be in the JSSP ORLIB format.
        /// </summary>
        /// <remarks>
        /// The stream is not closed or disposed. The caller has to take care of that.
        /// </remarks>
        /// <param name="stream">The stream to write data to.</param>
        public void Export(Stream stream)
        {
            //TODO: complete Export, seems as if it is just a dummy (copy-paste)-implementation
            using (var writer = new StreamWriter(stream, Encoding.UTF8, 4092, true))
            {
                writer.WriteLine(Name);
                writer.WriteLine(Description);
                writer.WriteLine(Jobs.ToString(CultureInfo.InvariantCulture.NumberFormat) + " " + Machines.ToString(CultureInfo.InvariantCulture.NumberFormat));
                for (int i = 0; i < Machines; i++)
                {
                    for (int j = 0; j < Jobs; j++)
                    {
                        writer.Write(ProcessingTimes[i, j] + " ");
                    }
                    writer.WriteLine();
                }
                writer.Flush();
            }
        }

    }
}