using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace crusherScanner
{
    internal class WorkingDirControl
    {
        /// <summary>
        /// Update sample as scanned in the working directory.
        /// </summary>
        /// <param name="e">Sample data containing Job and Barcode.</param>
        public static void UpdateWorkingDir(System.ComponentModel.DoWorkEventArgs e)
        {
            if (e.Argument == null)
            {
                return;
            }
            Scan scanData = (Scan)e.Argument;
            string[] DataDirs = new string[2] { Properties.Settings.Default.OreDefWorkFile, Properties.Settings.Default.OreDefInFile };
            string? JobFile = GetJobFilePath(scanData, DataDirs);
            if (JobFile != null)
            {
                if (JobFile.Contains(DataDirs[0]))
                {
                    scanData = updateSampleInJobFile(scanData, JobFile);
                }
                else
                {
                    try
                    {
                        File.Move($"{DataDirs[1]}\\{scanData.sampleData.Job}.csv", $"{DataDirs[0]}\\{scanData.sampleData.Job}.csv");
                        scanData = updateSampleInJobFile(scanData, $"{DataDirs[0]}\\{scanData.sampleData.Job}.csv");
                    }
                    catch (Exception)
                    {
                        
                    }
                }
                e.Result = scanData;
            }
            else
            {
                e.Result = scanData; // This shouldn't happen.
            }
        }

        /// <summary>
        /// Is the currently scanned sample's job in the working directory.
        /// </summary>
        /// <param name="scanData">Sample data containing Job and Barcode.</param>
        /// <param name="DataDirs"></param>
        private static string? GetJobFilePath(Scan scanData,string[] DataDirs)
        {
            try
            {
                foreach (var DataDir in DataDirs)
                {
                    if (Directory.Exists(DataDir))
                    {
                        var jobFiles = Directory.EnumerateFiles(DataDir, "ML??????.csv", SearchOption.TopDirectoryOnly);
                        foreach (var jobFile in jobFiles)
                        {
                            if (jobFile.Contains(scanData.sampleData.Job))
                            {
                                return jobFile;
                            }
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("An error occurred." + Environment.NewLine + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            return null;
        }

        private static Scan updateSampleInJobFile(Scan scanData, string DataFile)
        {
            List<string> fileLines = new();
            using FileStream OreDefWorkingFile = new(DataFile, FileMode.Open, System.IO.FileAccess.ReadWrite, FileShare.None);
            {
                using StreamReader Reader = new(OreDefWorkingFile);
                {
                    var line = Reader.ReadLine();
                    while (line != null)
                    {                       
                        if (line != null && line.Contains('\u002C'))
                        {
                            scanData.JobTotal++;
                            string[] CSV = line.Split('\u002C');
                            if(CSV[0] == scanData.sampleData.Sid)
                            {
                                CSV[8] = scanData.sampleData.Sid;
                                fileLines.Add(string.Join('\u002C', CSV));
                            }
                            else
                            {
                                fileLines.Add(line);
                            }
                            // Count if sample has been scanned already
                            if(CSV[8] != "")
                            {
                                scanData.JobCount++;
                            }
                            // set CSV to null to prevent data roll over
                            CSV = null;
                        }
                        line = Reader.ReadLine();
                    }
                }
                
                OreDefWorkingFile.Position = 0;
                using StreamWriter writer = new(OreDefWorkingFile);
                {
                    foreach (var line in fileLines)
                    {
                        writer.WriteLine(line);
                    }
                }
                writer.Close();
            }
            scanData.JobCount--; // Compensate for the file header
            scanData.JobTotal--; // Compensate for the file header
            return scanData;
        }

    }
}