using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Diagnostics;

namespace BBxCommon
{
    public class FileUtilities
    {
        public static void ByteArrayToFile(string fileName, byte[] byteArray)
        {
            // execute with using so the filestream is properly disposed
            using (FileStream fileStream = new FileStream(fileName, FileMode.Create, FileAccess.Write))
            {
                // Read the array and writes to file
                fileStream.Write(byteArray, 0, byteArray.Length);
                fileStream.Close();
            }
        }

        // execute with using so the filestream is properly disposed
        public static byte[] ReadFileToByteArray(string filePath)
        {
            byte[] buffer;

            using (FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
            {
                int length = (int)fileStream.Length;
                buffer = new byte[length];
                int count;
                int sum = 0;

                // read until Read method returns 0 (end of the stream has been reached)
                while ((count = fileStream.Read(buffer, sum, length - sum)) > 0)
                {
                    sum += count;  // sum is a buffer offset for next reading
                }

                fileStream.Close();
            }
            return buffer;
        }

        public class BBxPDF2Excel
        {
            public BBxPDF2Excel()
            {
            }

            public BBxPDF2Excel(string tempPath)
            {
                TempPath = tempPath;
            }

            // Default folder name for temp folder during extraction and conversion
            private const string DEFAULT_TEMP_NAME = @"PDFExtractTemp";

            // Application and Library name
            private const string DEFAULT_APP_NAME = @"PDF2Excel.exe";
            private const string DEFAULT_DLL_NAME = @"GDIPLUS.dll";

            private String _TempPath;
            public String TempPath
            {
                get
                {
                    // If this property has not been set, default it
                    if (String.IsNullOrEmpty(_TempPath))
                    {
                        _TempPath = String.Format(@"C:\{0}\", DEFAULT_TEMP_NAME);
                    }
                    return _TempPath;
                }
                set
                {
                    _TempPath = value;
                }
            }

            // Basic conversion types supported by utility
            public enum ConversionType
            {
                cxls,
                cxlsx,
                ccsv
            }

            /// <summary>
            /// Converts a PDF via file path to excel binary by type
            /// </summary>
            /// <param name="pdfPath"></param>
            /// <param name="type"></param>
            /// <returns></returns>
            public byte[] ConvertPDFToByteArray(string pdfPath, ConversionType type)
            {
                return ConvertPDFToByteArray(ReadFileToByteArray(pdfPath), type);
            }

            /// <summary>
            /// Converts a PDF via binary to excel binary by type
            /// </summary>
            /// <param name="pdf"></param>
            /// <param name="type"></param>
            /// <returns></returns>
            public byte[] ConvertPDFToByteArray(byte[] pdf, ConversionType type)
            {
                return new byte[0x1];
            }

            /// <summary>
            /// Converts PDF via file path to excel stored from file path by type
            /// </summary>
            /// <param name="pdfPath"></param>
            /// <param name="type"></param>
            /// <returns></returns>
            public string ConvertPDFToReturnedFilePath(string pdfPath, ConversionType type)
            {
                return ConvertPDFToReturnedFilePath(ReadFileToByteArray(pdfPath), type);
            }

            /// <summary>
            /// Converts PDF via binary to excel stored from file path by type
            /// </summary>
            /// <param name="pdf"></param>
            /// <param name="type"></param>
            /// <returns></returns>
            public string ConvertPDFToReturnedFilePath(byte[] pdf, ConversionType type)
            {
                return String.Empty;
            }

            /// <summary>
            /// Stubbed out Raw version of executing the command line utility
            /// </summary>
            /// <param name="args"></param>
            public void ExecuteRawCommand(string args)
            {
                // Extract Lib for usage
                ExtractResource();

                // Construct command
                Process p = new Process();
                p.StartInfo.WindowStyle = ProcessWindowStyle.Hidden; // Hide the command window
                p.StartInfo.FileName = String.Format(@"{0}\{1}", TempPath, DEFAULT_APP_NAME);
                p.StartInfo.Arguments = args;
                p.Start();

                // We want to wait for this command to finish, and not let go of the thread quite yet
                p.WaitForExit();

                // Remove the exe for cleanup
                CleanupResources();
            }

            /// <summary>
            /// Extracts application from resource
            /// </summary>
            private void ExtractResource()
            {
                // Ensure the temp directory is created, if not, create it
                if (!Directory.Exists(TempPath))
                {
                    Directory.CreateDirectory(TempPath);
                }

                // Extract the application and the lib
                ByteArrayToFile(String.Format(@"{0}\{1}", TempPath, DEFAULT_APP_NAME), rcPDF2Excel.PDF2Excel);
                ByteArrayToFile(String.Format(@"{0}\{1}", TempPath, DEFAULT_DLL_NAME), rcPDF2Excel.GDIPLUS);
            }

            /// <summary>
            /// Cleans up temp directory from resource extraction
            /// </summary>
            private void CleanupResources()
            {
                // If the temp directory doesnt exist, we know an error occured and dont need
                // to waste cpu deleting something that doesnt exist
                if (!Directory.Exists(TempPath))
                {
                    return;
                }

                // Cleanup the temp directory
                File.Delete(String.Format(@"{0}\{1}", TempPath, DEFAULT_APP_NAME));
                File.Delete(String.Format(@"{0}\{1}", TempPath, DEFAULT_DLL_NAME));
            }
        }

        public class ExcelParser
        {

        }

    }
}