using PdfSharp.Drawing;
using PdfSharp.Pdf;
using Simulator.Models;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;
using System.Web.Mvc;

namespace Simulator.Controllers
{
    public class HomeController : Controller
    {
        private static SimulatorDbContext db = new SimulatorDbContext("Server=localhost;Database=simulator;Uid=simulator;Pwd=W5Cok8HAy1XoSa63qaRiM5BA8i1E6I;");
        private static string _PrivateDirectory = @"C:\pba\private";


        public ActionResult Index()
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }

            Args args = new Args();
            args.Patienten = db.GetPatienten();
            args.Befunde = db.GetBefunde();
            return View(args);
        }

        [HttpPost]
        public ActionResult createPatient(Patient patient)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }

            object response = new { status = "", message = "" };

            if (patient == null || string.IsNullOrEmpty(patient.Name))
            {
                response = new { status = "error", message = "Bitte geben Sie den Namen des Patienten ein" };
            }
            else if (string.IsNullOrEmpty(patient.PLZ))
            {
                response = new { status = "error", message = "Bitte geben Sie die PLZ des Patienten ein" };
            }
            else if(string.IsNullOrEmpty(patient.Gebdatum))
            {
                response = new { status = "error", message = "Bitte geben Sie das Geburtsdatum des Patienten ein" };
            }
            else
            {
                DateTime created_dt = default(DateTime);

                if (patient.Gebdatum.Length < 10 || !DateTime.TryParseExact(patient.Gebdatum.Substring(0,10), "yyyy-MM-dd", new CultureInfo("de-DE"), DateTimeStyles.None, out created_dt))
                {
                    response = new { status = "error", message = "Das Geburtsdatum wurde in falschem Format angegeben" };
                }
                else
                {
                    if(db.PatientExists(patient.Name))
                    {
                        response = new { status = "error", message = "Ein Patient mit dem Namen existiert bereits" };
                    }
                    else
                    {
                        if (db.CreatePatient(patient))
                        {
                            response = new { status = "success", message = "Patient wurde erfolgreich angelegt" };
                        }
                        else
                        {
                            response = new { status = "error", message = "Patient konnte nicht angelegt werden" };
                        }
                    }
                }
            }

            return Json(response);
        }

        [HttpPost]
        public ActionResult createBefund(Befund befund)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }



            object response = new { status = "", message = "" };

            if (befund == null || string.IsNullOrEmpty(befund.Auftragsnummer))
            {
                response = new { status = "error", message = "Bitte geben Sie die Auftragsnummer ein" };
            }
            else if (string.IsNullOrEmpty(befund.Inhalt))
            {
                response = new { status = "error", message = "Bitte geben Sie den Befundinhalt ein" };
            }
            else if (befund.PatientId <= 0)
            {
                response = new { status = "error", message = "Bitte wählen Sie einen Patient aus" };
            }
            else
            {
                if (db.BefundExists(befund.Auftragsnummer))
                {
                    response = new { status = "error", message = "Die Auftragsnummer existiert bereits, bitte geben Sie eine andere Auftragsnummer ein" };
                }
                else
                {
                    Patient patient = db.GetPatient(befund.PatientId);

                    if(patient != null)
                    {
                        if (db.CreateBefund(befund, patient))
                        {

                            if (!string.IsNullOrEmpty(patient.UDID))
                            {
                                System.IO.File.AppendAllText(@"C:\tmp\simulator.txt", "Patient hat UDID:" + patient.UDID + "\r\n");

                                SendBefund(befund, patient);
                            }

                            response = new { status = "success", message = "Befund wurde erfolgreich angelegt" };
                        }
                        else
                        {
                            response = new { status = "error", message = "Befund konnte nicht angelegt werden" };
                        }
                    }
                    else
                    {
                        response = new { status = "error", message = "Patient wurde nicht gefunden" };
                    }
                }
            }

            return Json(response);
        }

        [HttpPost]
        public ActionResult deletePatient(int id)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }



            object response = new { status = "", message = "" };

            if (db.PatientDelete(id))
            {
                response = new { status = "success", message = "Patient wurde erfolgreich gelöscht" };
            }
            else
            {
                response = new { status = "error", message = "Patient konnte nicht gelöscht werden" };
            }

            return Json(response);
        }

        [HttpPost]
        public ActionResult deleteBefund(int id)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }



            object response = new { status = "", message = "" };

            if (db.BefundDelete(id))
            {
                response = new { status = "success", message = "Befund wurde erfolgreich gelöscht" };
            }
            else
            {
                response = new { status = "error", message = "Befund konnte nicht gelöscht werden" };
            }

            return Json(response);
        }


        [HttpPost]
        public ActionResult printBefund(int id, string inhalt)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }


            object response = new { status = "", message = "" };
            
            if (id > 0)
            {
                Befund befund = db.GetBefund(id);

                if(befund != null)
                {
                    Patient patient = db.GetPatient(befund.PatientId);

                    if(patient != null)
                    {
                        befund.Inhalt = inhalt;

                        if (SendBefund(befund, patient))
                        {
                            response = new { status = "success", message = "Befund wurde erfolgreich gedruckt" };
                        }
                        else
                        {
                            response = new { status = "error", message = "Befund konnte nicht gedruckt werden" };
                        }
                    }
                    else
                    {
                        response = new { status = "error", message = "Patient wurde nicht gefunden" };
                    }
                }
                else
                {
                    response = new { status = "error", message = "Befund konnte nicht gedruckt werden" };
                }
            }
            else
            {
                response = new { status = "error", message = "Befund wurde nicht gefunden" };
            }

            return Json(response);
        }

        [HttpPost]
        public ActionResult getBefund(int id)
        {
            if (this.Session == null || this.Session["user"] == null)
            {
                return RedirectToAction("Index", "Login");
            }

            object response = new { status = "", message = "" };
            Befund befund = db.GetBefund(id);

            if (befund != null)
            {
                response = new { status = "success", befund = befund };
            }
            else
            {
                response = new { status = "error", message = "Befund wurde nicht gefunden" };
            }

            return Json(response);
        }


        public static bool SendBefund(Befund befund, Patient patient)
        {
            bool result = false;

            try
            {
                if (patient != null && !string.IsNullOrEmpty(patient.UDID))
                {
                    befund.UDID = patient.UDID;

                    PdfDocument document = new PdfDocument();
                    PdfPage page = document.AddPage();
                    XGraphics gfx = XGraphics.FromPdfPage(page);
                    XFont font = new XFont("Verdana", 20, XFontStyle.Bold);

                    gfx.DrawString("Patient: " + patient.Name + " (" + patient.PatientId + ")", new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 100);
                    gfx.DrawString("PLZ:" + patient.PLZ, new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 120);
                    gfx.DrawString("Geburtsdatum: " + patient.Gebdatum, new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 140);
                    gfx.DrawString("Auftragsnummer: " + befund.Auftragsnummer, new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 160);

                    gfx.DrawString("BEFUND: " + befund.Auftragsnummer, new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 200);
                    gfx.DrawString(befund.Inhalt, new XFont("Arial", 16, XFontStyle.Bold), XBrushes.Black, 100, 220);

                    string pdf_filename = Path.Combine(Path.GetDirectoryName(AppDomain.CurrentDomain.BaseDirectory), Guid.NewGuid().ToString().ToLower().Replace("-", "") + ".pdf");

                    System.IO.File.AppendAllText(@"C:\tmp\simulator.txt", "PDF:" + pdf_filename + "\r\n");

                    if (System.IO.File.Exists(pdf_filename))
                    {
                        System.IO.File.Delete(pdf_filename);
                    }

                    document.Save(pdf_filename);

                    string base64 = Convert.ToBase64String(System.IO.File.ReadAllBytes(pdf_filename));
                    string pgs = SHA512HASH(patient.PLZ + patient.Gebdatum + befund.Auftragsnummer);
                    string testhl7 = Path.Combine(Path.GetDirectoryName(AppDomain.CurrentDomain.BaseDirectory), "befund.hl7");
                    string content = System.IO.File.ReadAllText(testhl7);

                    content = content.Replace("[BIRTHDAY]", patient.Gebdatum);
                    content = content.Replace("[ZIP]", patient.PLZ);
                    content = content.Replace("[SAMPLEID]", befund.Auftragsnummer);
                    content = content.Replace("[PATID]", patient.PatientId.ToString());
                    content = content.Replace("[UDID]", patient.UDID);
                    content = content.Replace("[RESULTS]", base64);
                    content = content.Replace("[STATUS]", "COMPLETED");
                    content = content.Replace("[PGS]", pgs);

                    string newFile = Path.Combine(_PrivateDirectory, pgs + ".hl7");
                    System.IO.File.WriteAllText(newFile, content);

                    if (System.IO.File.Exists(newFile))
                    {                       
                        System.IO.File.Delete(pdf_filename);
                    }
                }

                befund.Status = "COMPLETED";

                if(db.UpdateBefund(befund))
                {
                    result = true;
                }
            }
            catch (Exception ex)
            {
                System.IO.File.AppendAllText(@"C:\tmp\simulator.txt", "ERROR:" + ex.Message + "\r\n");
            }

            return result;
        }

        public static string SHA512HASH(string value)
        {
            string result = null;

            try
            {
                byte[] bytes = Encoding.UTF8.GetBytes(value);

                using (System.Security.Cryptography.SHA512 hash = System.Security.Cryptography.SHA512.Create())
                {
                    byte[] hashedInputBytes = hash.ComputeHash(bytes);

                    StringBuilder hashedInputStringBuilder = new StringBuilder(128);

                    foreach (var b in hashedInputBytes)
                    {
                        hashedInputStringBuilder.Append(b.ToString("X2"));
                    }

                    result = hashedInputStringBuilder.ToString().ToLower();
                }
            }
            catch
            {
                result = null;
            }

            return result;
        }
    }
}