using System;
using System.IO;
using System.Xml.Linq;
using Deltares.Dam.Application.Live.Properties;
using Deltares.Dam.Data;
using Deltares.Dam.Data.Assemblers;
using Deltares.Standard.Application;

namespace Deltares.Dam.Application.Live
{
    public class ModelRunner : IModelRunner
    {
        internal const string NoDamxFile = "No .damx file set to load project data from.";
        internal const string NoFewsInputFileAvailable = "No FEWS input file available to read the input time series from.";
        internal const string NoFewsOutputFileAvailable = "No FEWS output file available to write the result to.";
        internal const string ErrorExtractingWorkingFolder = "An error occured while trying to extract the path from the FEWS input file. This error can be solved by setting a working folder";

        internal LogHelper Logger = LogHelper.Create<ModelRunner>();

        protected internal FileInfo DamXFile { get; set; }
        protected internal FileInfo FewsInputFile { get; set; }
        protected internal FileInfo FewsOutputFile { get; set; }
        protected internal FileInfo ParametersFile { get; set; }

        /// <summary>
        /// Gets or sets the DAM project data used for stability calculations
        /// </summary>
        public DamProjectData ProjectData { get; set; }

        public CalculationParameters CalculationParameters { get; set; }
        public TimeSerieCollection OutputTimeSeriesCollection { get; set; }
        public TimeSerieCollection InputTimeSeriesCollection { get; set; }

        public string StabilityWorkingPath { get; set; }
        public string PipingWorkingPath { get; set; }
        public string StabilityExePath { get; set; }
        public bool UseMStabForCalculation { get; set; }
        public double WaterLevelOffset { get; set; }
        public string WorkingPath { get; set; }
        public string Filter { get; set; }

        public IModelRunner RunnerDelegate { get; set; }

        public bool HasErrors
        {
            get { return Logger.HasLoggedExceptions; }
        }
        
        public ModelRunner()
        {
            // WorkingPath will be extracted from file name if available
            StabilityWorkingPath = Settings.Default.StabilityWorkingPath;
            PipingWorkingPath = Settings.Default.PipingWorkingPath;
            StabilityExePath = Path.Combine(System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location), Settings.Default.MStabExePath);
            UseMStabForCalculation = Settings.Default.UseMStabForCalculation;
            WaterLevelOffset = Settings.Default.WaterLevelOffset;                       
        }

        /// <summary>
        /// Initializes this instance. Validates input files, deletes former project files, 
        /// creates working folders and prepares the in and output time series collections
        /// </summary>
        public virtual void Initialize()
        {
            if (ProjectData == null)
            {
                if (DamXFile == null) 
                    throw new InvalidOperationException(NoDamxFile);

                ProjectData = DamProject.LoadData(DamXFile.FullName);
                WorkingPath = Path.ChangeExtension(DamXFile.FullName, ".Calc");
            }
                      
            if (InputTimeSeriesCollection == null)
            {
                if (FewsInputFile == null)
                    throw new InvalidOperationException(NoFewsInputFileAvailable);

                InputTimeSeriesCollection = TimeSerieCollection.LoadFromFile(FewsInputFile);
            }

            if (OutputTimeSeriesCollection == null)
            {
                if (FewsOutputFile == null)
                    throw new InvalidOperationException(NoFewsOutputFileAvailable);

                OutputTimeSeriesCollection = InputTimeSeriesCollection.GetShallowCopy();
            }

            if (CalculationParameters == null && ParametersFile != null)
            {
                // Read calculation parameters, if available
                CalculationParameters = CalculationParameters.LoadFromFile(ParametersFile);
            }
        }

        /// <summary>
        /// Creates and set's up the working directories. By default the directory the output file
        /// will be used if the working path is not set
        /// </summary>
        public virtual void CreateAndSetWorkingDirectories()
        {
            string targetPath;
            string defaultFolder = FewsOutputFile != null ? FewsOutputFile.DirectoryName : null;

            if (!string.IsNullOrWhiteSpace(WorkingPath))
            {
                targetPath = WorkingPath;
            }            
            else
            {
                if (defaultFolder == null)
                {                    
                    throw new InvalidOperationException(ErrorExtractingWorkingFolder);
                }

                targetPath = string.IsNullOrWhiteSpace(defaultFolder) ? "." : defaultFolder;
            }

            CreateWorkingDirectory(targetPath);

            // The following path's are sub folders of the main working path
            StabilityWorkingPath = Path.Combine(targetPath, StabilityWorkingPath);
            CreateWorkingDirectory(StabilityWorkingPath);

            PipingWorkingPath = Path.Combine(targetPath, PipingWorkingPath);
            CreateWorkingDirectory(PipingWorkingPath);
        }

        /// <summary>
        /// Creates the working directory if they not exist.
        /// </summary>
        /// <param name="directoryName">Name of the directory.</param>
        protected static void CreateWorkingDirectory(string directoryName)
        {
            if (string.IsNullOrWhiteSpace(directoryName))
                throw new ArgumentNullException("directoryName");

            if (!Directory.Exists(directoryName))
            {
                Directory.CreateDirectory(directoryName);
            }
        }

        /// <summary>
        /// Performs all the steps to transform the input time series collection to 
        /// the output time series collection with the calculated values
        /// </summary>
        public virtual void Run()
        {
            Initialize();            
            CreateAndSetWorkingDirectories();
            DeleteFormerProjectFiles();
            Process();
            WriteResultsToFile(FewsOutputFile.FullName);
        }

        /// <summary>
        /// Processes an output time series using the input time series collection 
        /// and the required project data.
        /// </summary>
        public virtual void Process()
        {
            if (ProjectData == null) 
                throw new InvalidOperationException("No DAM project data available.");

            if (InputTimeSeriesCollection == null) 
                throw new InvalidOperationException("No input time series collection available.");

            if (OutputTimeSeriesCollection == null) 
                throw new InvalidOperationException("No output time series collection available.");

            if (RunnerDelegate != null)
            {
                RunnerDelegate.WorkingPath = WorkingPath;
                RunnerDelegate.WaterLevelOffset = WaterLevelOffset;
                RunnerDelegate.StabilityExePath = StabilityExePath;
                RunnerDelegate.PipingWorkingPath = PipingWorkingPath;
                RunnerDelegate.UseMStabForCalculation = UseMStabForCalculation;
                RunnerDelegate.StabilityWorkingPath = StabilityWorkingPath;
                RunnerDelegate.CalculationParameters = CalculationParameters;
                RunnerDelegate.InputTimeSeriesCollection = InputTimeSeriesCollection;
                RunnerDelegate.OutputTimeSeriesCollection = OutputTimeSeriesCollection;                
                RunnerDelegate.ProjectData = ProjectData;
                RunnerDelegate.Filter = Filter;

                RunnerDelegate.Run();

                // sync back the processed data
                OutputTimeSeriesCollection = RunnerDelegate.OutputTimeSeriesCollection;
            }
            else
            {
                Logger.LogWarning("No model runner set to delegate the processing of the time series to");
            }
        }

        /// <summary>
        /// Cleanup the working directory
        /// </summary>
        protected void DeleteFormerProjectFiles()
        {
            // remove known files for stability calculation
            var di = new DirectoryInfo(StabilityWorkingPath);
            FileInfo[] rgFiles = di.GetFiles("*.st?");
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);
            rgFiles = di.GetFiles("*.sti.xml");
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);
            rgFiles = di.GetFiles("*.wmf");
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);
            rgFiles = di.GetFiles("*.err");
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);

            // remove known files for piping calculator
            di = new DirectoryInfo(PipingWorkingPath);
            rgFiles = di.GetFiles("*" + PipingCalculator.PipingFilenameExtension);
            foreach (FileInfo fi in rgFiles)
                File.Delete(fi.FullName);
        }

        /// <summary>
        /// Writes all the results in the output collection to the given file
        /// </summary>
        /// <param name="fileName"></param>
        protected void WriteResultsToFile(string fileName)
        {
            if (string.IsNullOrWhiteSpace(fileName))
                throw new ArgumentNullException("fileName");

            var timeSerieAssembler = new TimeSeriesAssembler();
            XDocument doc = timeSerieAssembler.CreateDataTransferDocument(OutputTimeSeriesCollection);

            try
            {
                doc.Save(fileName);
                FileWriterUtil.RemoveThreeBytesFromXml(fileName);
            }
            catch (Exception e)
            {
                Logger.LogError("Could not export Fews xml file", e);
            }
        }
    }
}