using System;
using System.IO;
using System.Diagnostics;
using System.Collections.Generic;
using System.Globalization;
using Spire.Xls;
using System.Reflection;

namespace bdf
{

    public class InvoiceCell       // Invoice Cells from Invoice Template
    {
        public String Account { get; set; } = "I2";         // "Account"+ (also I32)
        public String Date { get; set; } = "I3";            // I3 (also I33) 
        public String Invoice { get; set; } = "I4";         //I4 "Invoice" (also I34)
        public String Total_Charges { get; set; } = "I14";  //I14 (also I36)

        public String Account2 { get; set; } = "I32";       // "Account"+ (also I32)
        public String Date2 { get; set; } = "I33";          // I3 (also I33) 
        public String Invoice2 { get; set; } = "I34";       //I4 "Invoice" (also I34)
        public String Total_Charges2 { get; set; } = "I36"; //I14 (also I36)

        public String CCI { get; set; } = "C12";  // C12 "Canada Contract Identifier"

        public String PaperFee { get; set; } = "H17";
        public String LateCharge { get; set; } = "H18";
        public String Service_Charges { get; set; } = "I19";
        public String UsageCharges { get; set; } = "H20";
        public String TotalUsageCharges { get; set; } = "I21";
        public String DataMonthlyCharges { get; set; } = "H23";
        public String DataNon_RecurringCharges { get; set; } = "H24";
        public String DataTotalOtherCharges { get; set; } = "H25";
        public String Data_Services { get; set; } = "I27";
        public String TaxON_PST { get; set; } = "F29";
        public String TaxON_GST { get; set; } = "G29";
        public String TaxON_HST { get; set; } = "H29";
        public String TaxPQ_PST { get; set; } = "F30";
        public String TaxPQ_GST { get; set; } = "G30";
        public String TaxPQ_HST { get; set; } = "H30";
        public String Taxes { get; set; } = "I31";
    }

    /*
        // Source - https://stackoverflow.com/a
        // Posted by Alexandru
        // Retrieved 2025-12-03, License - CC BY-SA 3.0

        internal class OutputSink : IDisposable
        {
            [DllImport("kernel32.dll")]
            public static extern IntPtr GetStdHandle(int nStdHandle);

            [DllImport("kernel32.dll")]
            public static extern int SetStdHandle(int nStdHandle, IntPtr hHandle);

            private readonly TextWriter _oldOut;
            private readonly TextWriter _oldError;
            private readonly IntPtr _oldOutHandle;
            private readonly IntPtr _oldErrorHandle;

            public OutputSink()
            {
                _oldOutHandle = GetStdHandle(-11);
                _oldErrorHandle = GetStdHandle(-12);
                _oldOut = Console.Out;
                _oldError = Console.Error;
                Console.SetOut(TextWriter.Null);
                Console.SetError(TextWriter.Null);
                SetStdHandle(-11, IntPtr.Zero);
                SetStdHandle(-12, IntPtr.Zero);
            }

            public void Dispose()
            {
                SetStdHandle(-11, _oldOutHandle);
                SetStdHandle(-12, _oldErrorHandle);
                Console.SetOut(_oldOut);
                Console.SetError(_oldError);
            }
        }

*/

    public class PDF
    {
        public static void Demo()
        {
            //MakePDF();
            Dictionary<string, string> Invoice = new Dictionary<string, string> { };
            InvoiceCell ic = new InvoiceCell { };

            Invoice.Add(ic.Account, "Account P02-" + "123456"); //bdf2 C2   
            int d = 20250731;
            Invoice.Add(ic.Date, dateFormal(d));
            //string dt = "20250930";     
            Invoice.Add(ic.Invoice, ("Invoice " + d.ToString().Substring(4) + d.ToString().Substring(0, 4) + " - NU"));   //mmddyyyy 
            Invoice.Add(ic.Total_Charges, String.Format("${0:n}", 10000));

            Invoice.Add(ic.Account2, Invoice[ic.Account]);
            Invoice.Add(ic.Date2, Invoice[ic.Date]);
            Invoice.Add(ic.Invoice2, Invoice[ic.Invoice]);
            Invoice.Add(ic.Total_Charges2, Invoice[ic.Total_Charges]);

            customInvoice("doug", "", ref Invoice);
        }


        static void MakePDF()
        {
            // Create a Workbook object
            Spire.Xls.Workbook workbook = new Spire.Xls.Workbook();

            // Load an Excel file (replace with your file path)
            workbook.LoadFromFile("test.xlsx");

            //PdfFont fieldFont = new PdfFont(PdfFontFamily.Helvetica, 10f);

            // Get the first worksheet
            Spire.Xls.Worksheet sheet = workbook.Worksheets[0];

            // Set the print area to a specific cell range
            // Comment this line out if you need to export the entire worksheet as a PDF
            //sheet.PageSetup.PrintArea = "B1:E6";

            // Optional: Set worksheets to fit to page when converting
            workbook.ConverterSetting.SheetFitToPage = true;

            // Save the Excel file to PDF
            workbook.SaveToFile("Output.pdf", FileFormat.PDF);

            // Dispose resources
            workbook.Dispose();
        }

        static void LoadStream()
        {

            // 1. Create a Workbook instance
            Workbook workbook = new Workbook();

            // 2. Create a Stream object (example using FileStream)
            // Replace "sample.xls" with your actual file path or retrieve the stream from your source
            FileStream fileStream = System.IO.File.OpenRead("sample.xls");

            // Ensure the stream position is at the beginning (if necessary)
            fileStream.Seek(0, SeekOrigin.Begin);

            // 3. Use the Workbook.LoadFromStream() method to load the file
            try
            {
                workbook.LoadFromStream(fileStream);
            }
            catch (Exception ex)
            {
                // Handle exceptions, e.g., file format not supported (Excel 95 or earlier not supported)
                Logger.Log(0, "Error loading stream: {0}", ex.Message);
            }
            finally
            {
                // 4. Close the stream after loading
                fileStream.Dispose();
            }

            // Now you can work with the workbook data
            Worksheet sheet = workbook.Worksheets[0];
            // ... do operations like reading cells, etc. ...

            // Example of saving the processed file to a new file
            workbook.SaveToFile("From_stream_processed.xls", ExcelVersion.Version97to2003);
            Process.Start("From_stream_processed.xls");

        }

        static void LoadStreamXLSX()
        {
            // 1. Create a Workbook instance
            Workbook workbook = new Workbook();

            // 2. Open a FileStream from your source file
            using (FileStream fileStream = System.IO.File.OpenRead("Sample.xlsx"))
            {
                // Ensure the stream position is at the beginning
                fileStream.Seek(0, SeekOrigin.Begin);

                // 3. Load the workbook from the stream
                workbook.LoadFromStream(fileStream);

                // 4. (Optional) Work with the workbook, e.g., modify a cell
                workbook.Worksheets[0].Range["A1"].Text = "Data loaded from stream!";

                // (Optional) Save the result to a new stream or file
                // workbook.SaveToStream(outputStream);
                // workbook.SaveToFile("Output.xlsx", ExcelVersion.Version2016);
            }
        }

        public static Workbook LoadEmbeddedWorkbook(string resourceName)
        {
            // Get the assembly where the resource is stored
            Assembly asm = Assembly.GetExecutingAssembly();

            // Fully-qualified resource name (namespace + filename)
            Stream stream = asm.GetManifestResourceStream(resourceName);

            if (stream == null)
                throw new Exception("Embedded resource not found: " + resourceName);

            Workbook wb = new Workbook();
            wb.LoadFromStream(stream);   // FreeSpire.XLS supports this

            stream.Close();
            return wb;
        }

        public static void customInvoice(string type, string trace, ref Dictionary<string, string> CellData)
        {
            //string fontDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "");
            string fontDirectory = AppDomain.CurrentDomain.BaseDirectory;   // for non Windows systems use the .exe folder
            //string fontDirectory2 = @"C:\\Windows\\Fonts\\";
            //string[] fontDirectories = { fontDirectory, fontDirectory2 };
            string[] fontDirectories = { fontDirectory };

            /* Set the custom font file directory for the workbook instance
            TextWriter originalOutput = Console.Out;

            // Temporarily suppress console output
            Console.SetOut(TextWriter.Null);

            Workbook workbook = new Workbook();   // spews Not Implemented error

            // Restore the original standard output writer
            //Console.SetError(originalOutput);

            //Console.SetOut(originalOutput);


            /*
            // Store the original listeners
            var originalListeners = Debug.Listeners;

            // Temporarily clear the listeners to suppress all Debug output
            Debug.Listeners.Clear();

            // Code here that generates unwanted debug output (e.g., a noisy library call)
            Workbook workbook = new Workbook();   // spews Not Implemented error 

            // Re-add the original listeners (or just the DefaultTraceListener)
            Debug.Listeners.Add(new DefaultTraceListener());

            */
            Workbook workbook = new Workbook();

            workbook = LoadEmbeddedWorkbook("BDF.Embedded.template.xlsx");
            Logger.Log(" ...this will take a few seconds");

            int dpi = 600;// image conversion resolution
            workbook.ConverterSetting.XDpi = (dpi);
            workbook.ConverterSetting.YDpi = (dpi);
            workbook.ConverterSetting.JPEGQuality = 99;
            //workbook.ConverterSetting.

            // Create PdfSaveOptions instance
            //PdfSaveOptions options = new Converter.PdfSaveOptions();

            // Set a higher image resolution (e.g., 300 dpi for print quality)
            //options.ImageResolution = 600; // You can experiment with values like 144, 220, or 300

            // Save to PDF using the options
            //workbook.SaveToFile("output_high_quality.pdf", options);

            /*
            using (new OutputSink())
            {
            Console.WriteLine("a");
            workbook = new Workbook();   // spews Not Implemented error
            Console.WriteLine("b");
            }
            */
            workbook.CustomFontFileDirectory = fontDirectories;

            /* 1. Create a Workbook instance
            //Workbook workbook = new Workbook();

            // 2. Open a FileStream from your source file
            using (FileStream fileStream = System.IO.File.OpenRead("template.xlsx"))        //FIXME add checking
            {
                // Ensure the stream position is at the beginning
                fileStream.Seek(0, SeekOrigin.Begin);

                // 3. Load the workbook from the stream
                workbook.LoadFromStream(fileStream);
            */

            {
                // 4. (Optional) Work with the workbook, e.g., modify a cell
                foreach (var cell in CellData)
                {
                    // workbook.Worksheets[0].Range["A1"].Text = "Data loaded from stream!";
                    workbook.Worksheets[0].Range[cell.Key].Text = cell.Value;

                } // end foreach

                //Spire.Xls.Worksheet sheet = workbook.Worksheets[0];

                // Set the print area to a specific cell range
                // Comment this line out if you need to export the entire worksheet as a PDF
                //sheet.PageSetup.PrintArea = "B1:E6";

                // Optional: Set worksheets to fit to page when converting
                workbook.ConverterSetting.SheetFitToPage = true;

                // (Optional) Save the result to a new stream or file
                // workbook.SaveToStream(outputStream);
                // workbook.SaveToFile("Output.xlsx", ExcelVersion.Version2016);
                // Save the Excel file to PDF
                // string pdf_name = "Output_" + type + ".pdf";

                InvoiceCell ic = new InvoiceCell { };
                string prefix = CellData[ic.Invoice].Substring(0, 16).Replace(' ', '_') + "_";


                string pdf_name = prefix + type.ToUpper() + trace + ".pdf";
                workbook.SaveToFile(pdf_name, FileFormat.PDF);
                Logger.Log(0, "PDF written! ({0})", pdf_name);
            }  //end using
        }

        public static string dateFormal(int dateInt)
        {
            //int dateInt = 20251130;
            string dateString = dateInt.ToString();

            // 1. Define the input format ("yyyyMMdd")
            string inputFormat = "yyyyMMdd";

            // 2. Parse the string into a DateTime object

            DateTime dateTimeObject = DateTime.ParseExact(
                dateString,
                inputFormat,
                CultureInfo.InvariantCulture
            );

            // 3. Define the desired output format ("MMMM dd, yyyy")
            // MMMM = Full month name
            // dd   = Day of the month
            // yyyy = Year

            string outputFormat = "MMMM d, yyyy";
            string result = dateTimeObject.ToString(outputFormat);

            //Console.WriteLine(result);
            // Output: November 30, 2025
            return result;
        }

    }



    /*

    // Ensure these files are present in this directory in your application's deployment environment.
    string fontDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Fonts");
    string[] fontDirectories = { fontDirectory };

    // Set the custom font file directory for the workbook instance
    Workbook workbook = new Workbook();
    workbook.CustomFontFileDirectory = fontDirectories; //

    // Load your Excel file
    workbook.LoadFromFile("InputFile.xls");

    // ... perform other operations ...

    // When saving or converting (e.g., to PDF), the library will check the specified path for fonts
    workbook.SaveToFile("OutputFile.xlsx", ExcelVersion.Version2013);

    */

}