using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using Comal.Classes;
using InABox.Core;
using InABox.Clients;
using XF.Material.Forms.UI.Dialogs;
using System.IO;
using Xamarin.Essentials;

namespace PRS.Mobile
{

    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class StoreRequiConfirmationPage 
    {
        #region Fields
        public delegate void SaveSelectedEvent();
        public event SaveSelectedEvent OnSaveSelected;
        JobShell job = new JobShell();
        bool newRequi;
        Requisition requisition;
        bool isNewRequest = false;
        Dictionary<Image, Document> imagesDocuments = new Dictionary<Image, Document>();
        List<StoreRequiItemShell> requiItems = new List<StoreRequiItemShell>();
        List<StoreRequiItemShell> oldrequiitems = new List<StoreRequiItemShell>();
        #endregion

        #region Constructor and appearing
        public StoreRequiConfirmationPage(Requisition _requisition, List<StoreRequiItemShell> _requiitems, List<StoreRequiItemShell> _oldrequiitems) //requi could be existing or a blank/new requi (ID empty)
        {
            InitializeComponent();
            requiItems = _requiitems;
            if (requiItems[0].IsNotes == true)
            {
                requiItems.RemoveAt(0);
            }
            oldrequiitems = _oldrequiitems;
            requiStatusLbl.IsVisible = true;
            requiStatusFrame.IsVisible = true;
            boxesLbl.IsVisible = true;
            boxesQtyFrame.IsVisible = true;
            photosLbl.IsVisible = true;
            photosFrame.IsVisible = true;
            if (_requisition.ID != Guid.Empty)
                forDeliveryRb.IsChecked = true;
            else
                takenNowRb.IsChecked = true;
            dueLbl.IsVisible = false;
            dueFrame.IsVisible = false;
            ChooseTrack(_requisition);
        }

        public StoreRequiConfirmationPage() //when no requi is passed, app is creating a new requi request
        {
            InitializeComponent();
            isNewRequest = true;
            NewRequiTrack();
            UpdateColours();
            notesTitleLbl.Text = "Request";
            dueDatePckr.IsEnabled = true;
            reduceQtyBtn.IsEnabled = false;
            increaseQtyBtn.IsEnabled = false;
            TakePhoto.IsEnabled = false;
            ChooseImage.IsEnabled = false;
        }

        private void ChooseTrack(Comal.Classes.Requisition _requisition)
        {
            if (_requisition.ID == Guid.Empty)
            {
                NewRequiTrack();
            }
            else
            {
                ExistingRequiTrack(_requisition);
            }
        }

        private void NewRequiTrack()
        {
            newRequi = true;
            requisition = new Requisition();
            requisition.Title = "New Requisition";
            requisition.Boxes = 1;
            boxQtyLbl.Text = requisition.Boxes.ToString();
            titleLbl.Text = "New Requisition";
            requisition.Title = "New Requisition";
            requisition.Due = DateTime.Now;
            requisition.RequestedBy.ID = App.Data.Me.ID;
            requisition.RequestedBy.Name = App.Data.Me.Name;
            //create new requi
        }

        private void ExistingRequiTrack(Comal.Classes.Requisition _requisition)
        {
            newRequi = false;
            requisition = _requisition;
            titleLbl.Text = "Requi " + _requisition.Number.ToString();
            LoadPhotos();
            UpdateScreen();
        }
        #endregion

        #region Screen Update
        private void UpdateScreen()
        {
            jobLbl.Text = requisition.JobLink.JobNumber + " " + requisition.JobLink.Name;
            boxQtyLbl.Text = requisition.Boxes.ToString();
            if (string.IsNullOrEmpty(notesEdt.Text))
            {
                List<string> notes = new List<string>();
                foreach (string s in requisition.Notes)
                {
                    string substring = s.Replace("=", string.Empty);
                    substring = substring.Trim();
                    if (!string.IsNullOrWhiteSpace(substring))
                        notes.Add(substring);
                }
                notesEdt.Text = String.Join("\n", notes);
            }
            UpdateColours();
        }

        private void UpdateColours()
        {
            if (requisition.JobLink.ID == Guid.Empty)
                jobFrame.BorderColor = Color.Red;
            else
                jobFrame.BorderColor = Color.Gray;
            if (images.Children.Count == 0)
                photosFrame.BorderColor = Color.Red;
            else
                photosFrame.BorderColor = Color.Gray;
            if (isNewRequest)
                photosFrame.BorderColor = Color.Gray;
        }

        private void LoadPhotos()
        {
            if (requisition.Documents != 0)
            {
                var table = QueryPhotos();
                while (table == null)
                    table = QueryPhotos();
                if (table.Rows.Count != 0)
                {
                    foreach (var row in table.Rows)
                    {
                        List<object> list = row.Values;
                        if (list[0] == null) { list[0] = Guid.Empty; }
                        Guid requisitionDocLinkID = Guid.Parse(list[0].ToString());
                        Client.Query(
                            new Filter<Document>(x => x.ID).IsEqualTo(requisitionDocLinkID),
                            Columns.All<Document>(),
                            null,
                            (t, e) =>
                            {
                                CoreRow docrow = t.Rows.FirstOrDefault();
                                if (docrow != null)
                                {
                                    byte[] data = docrow.Get<Document, byte[]>(x => x.Data);
                                    ImageSource src = ImageSource.FromStream(() => new MemoryStream(data));
                                    Image img = new Image();
                                    img.HeightRequest = 150;
                                    img.WidthRequest = 150;
                                    img.Aspect = Aspect.AspectFit;
                                    img.Source = src;
                                    img.GestureRecognizers.Add(new TapGestureRecognizer
                                    {
                                        Command = new Command(OnTap),
                                        CommandParameter = src,
                                        NumberOfTapsRequired = 1
                                    });
                                    Device.BeginInvokeOnMainThread(() =>
                                    {
                                        ImageScroller.IsVisible = true;
                                        images.Children.Add(img);
                                        UpdateColours();
                                    });
                                }
                            }
                            );
                    }
                }

            }
        }

        private CoreTable QueryPhotos()
        {
            try
            {
                return new Client<RequisitionDocument>().Query(
                new Filter<RequisitionDocument>(x => x.EntityLink.ID).IsEqualTo(requisition.ID),
                new Columns<RequisitionDocument>(ColumnTypeFlags.None).Add(x => x.DocumentLink.ID),
                null
                );
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                return null;
            }
        }
        #endregion

        #region Selection
        private void SelectJobBtn_Clicked(object sender, EventArgs e)
        {
            JobSelectionPage jobSelectionPage = new JobSelectionPage(
                (job) =>
                {
                    if (job != null)
                    {
                        requisition.JobLink.ID = job.ID;
                        requisition.JobLink.Name = job.Name;
                        requisition.JobLink.JobNumber = job.JobNumber;
                        UpdateScreen();
                    }
                }
            );
            Navigation.PushAsync(jobSelectionPage);
        }

        private void ReduceQtyBtn_Clicked(object sender, EventArgs e)
        {
            if (requisition.Boxes <= 1)
                return;
            else
            {
                requisition.Boxes--;
                UpdateScreen();
            }
        }

        private void IncreaseQtyBtn_Clicked(object sender, EventArgs e)
        {
            requisition.Boxes++;
            UpdateScreen();
        }
        private void DueDatePckr_DateSelected(object sender, EventArgs e)
        {
            requisition.Due = dueDatePckr.Date;
        }

        #endregion

        #region Photos
        private void TakePhoto_Clicked(object sender, EventArgs e)
        {
            TakeAPhoto();
        }

        private void ChooseImage_Clicked(object sender, EventArgs e)
        {
            ChooseAPhoto();
        }

        private async void TakeAPhoto()
        {
            var file = await MediaPicker.CapturePhotoAsync();

            if (file == null)
                return;

            using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Adding Photo"))
            {
                Image img = null;
                var memoryStream = new MemoryStream();
                using (var stream = await file.OpenReadAsync())
                    await stream.CopyToAsync(memoryStream);
                var data = memoryStream.ToArray();

                Document doc = new Document()
                {
                    FileName = Path.GetFileName(file.FileName),
                    Data = data,
                    CRC = CoreUtils.CalculateCRC(data),
                    TimeStamp = DateTime.Now
                };

                ImageSource src = ImageSource.FromStream(() => new MemoryStream(data));
                img = new Image();
                img.HeightRequest = 150;
                img.WidthRequest = 150;
                img.Aspect = Aspect.AspectFit;
                img.Source = src;
                img.GestureRecognizers.Add(new TapGestureRecognizer
                {
                    Command = new Command(OnTap),
                    CommandParameter = src,
                    NumberOfTapsRequired = 1
                });

                imagesDocuments.Add(img, doc);
                
                if (img != null)
                {
                    Device.BeginInvokeOnMainThread(() =>
                    {
                        ImageScroller.IsVisible = true;
                        images.Children.Add(img);
                        UpdateColours();
                    });
                }

            }
        }

        private async void ChooseAPhoto()
        {
            var file = await MediaPicker.PickPhotoAsync();
            if (file == null)
                return;


            using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Adding Photo"))
            {
                Image img = null;
                var memoryStream = new MemoryStream();
                using (var stream = await file.OpenReadAsync())
                    await stream.CopyToAsync(memoryStream);
                var data = memoryStream.ToArray();

                Document doc = new Document()
                {
                    FileName = Path.GetFileName(file.FileName),
                    Data = data,
                    CRC = CoreUtils.CalculateCRC(data),
                    TimeStamp = DateTime.Now
                };


                ImageSource src = ImageSource.FromStream(() => new MemoryStream(data));
                img = new Image();
                img.HeightRequest = 150;
                img.WidthRequest = 150;
                img.Aspect = Aspect.AspectFit;
                img.Source = src;
                img.GestureRecognizers.Add(new TapGestureRecognizer
                {
                    Command = new Command(OnTap),
                    CommandParameter = src,
                    NumberOfTapsRequired = 1
                });

                imagesDocuments.Add(img, doc);
                
                if (img != null)
                {
                    Device.BeginInvokeOnMainThread(() =>
                    {
                        ImageScroller.IsVisible = true;
                        images.Children.Add(img);
                        UpdateColours();
                    });
                }
            }
        }

        private void OnTap(object obj)
        {
            ImageViewerPage viewer = new ImageViewerPage(obj as ImageSource, () => DeleteImage(obj));
            Navigation.PushAsync(viewer);
        }

        private void DeleteImage(object obj)
        {
            Image img = imagesDocuments.Keys.First(x => x.Source.Equals(obj as ImageSource));
            imagesDocuments.Remove(img);
            Device.BeginInvokeOnMainThread(() =>
            {
                images.Children.Clear();
                if (imagesDocuments.Count > 0)
                {
                    foreach (Image image in imagesDocuments.Keys)
                    {
                        images.Children.Add(image);
                    }
                }

                UpdateColours();
            });
        }

        #endregion

        #region Save
        private async void SaveBtn_Clicked(object sender, EventArgs e)
        {
            if (CheckSaveOk())
            {
                if (isNewRequest)
                {
                    requisition.Request = notesEdt.Text;
                    DoSaveRequi(requisition);
                    DisplayAlert("Success", "Requisition " + requisition.Number + " Created", "Ok");
                }
                else
                {
                    if (takenNowRb.IsChecked)
                    {
                        requisition.TakenBy.ID = App.Data.Me.ID;
                        requisition.TakenBy.Name = App.Data.Me.Name;
                    }
                    using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Saving"))
                    {
                        SaveRequi();
                    }
                    if (requisition.ID != Guid.Empty)
                    {
                        using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Saving"))
                        {
                            SavePhotos();
                            SaveItems();
                        }
                        await DisplayAlert("Success", "Requisition " + requisition.Number + " Saved", "Ok");
                        OnSaveSelected?.Invoke();
                        Navigation.PopAsync();
                    }

                }
            }
        }
        private Requisition DoSaveRequi(Comal.Classes.Requisition requisition)
        {
            try
            {
                new Client<Comal.Classes.Requisition>().Save(requisition, "Created on Mobile Device");
                return requisition;
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                return DoSaveRequi(requisition);
            }
        }

        private void SaveRequi()
        {
            requisition.Filled = DateTime.Now;
            requisition.Notes = new string[] { notesEdt.Text };
            DoSaveRequi(requisition);
        }

        private void SaveItems()
        {
            Task.Run(() =>
            {
                List<RequisitionItem> toDelete = new List<RequisitionItem>();
                if (oldrequiitems.Count > 0)
                {
                    foreach (StoreRequiItemShell oldshell in oldrequiitems)
                    {
                        StoreRequiItemShell shell = requiItems.Find(x => x.ID.Equals(oldshell.ID));
                        if (shell == null)
                        {
                            toDelete.Add(new RequisitionItem { ID = oldshell.ID });
                        }
                    }
                    if (toDelete.Count > 0)
                    {
                        DoDeleteRequiItems(toDelete);
                    }
                }
            });
            List<RequisitionItem> toSave = new List<RequisitionItem>();
            foreach (StoreRequiItemShell requiItemShell in requiItems)
            {
                RequisitionItem item = new RequisitionItem();
                item.RequisitionLink.ID = requisition.ID;
                item.ID = requiItemShell.ID;
                item.Product.ID = requiItemShell.ProductID;
                item.Product.Code = requiItemShell.ProductCode;
                item.Product.Name = requiItemShell.ProductName;
                item.Location.ID = requiItemShell.LocationID;
                item.Quantity = requiItemShell.Quantity;
                item.Description = requiItemShell.ProductName;
                item.Code = requiItemShell.ProductCode;
                item.JobLink.ID = requiItemShell.JobID;
                item.Style.ID = requiItemShell.StyleID;

                item.Picked = item.Picked == DateTime.MinValue ? DateTime.Now : item.Picked;

                item.Dimensions.Unit.ID = requiItemShell.Dimensions.Unit.ID;
                item.Dimensions.Unit.HasQuantity = requiItemShell.Dimensions.Unit.HasQuantity;
                item.Dimensions.Unit.HasLength = requiItemShell.Dimensions.Unit.HasLength;
                item.Dimensions.Unit.HasHeight = requiItemShell.Dimensions.Unit.HasHeight;
                item.Dimensions.Unit.HasWeight = requiItemShell.Dimensions.Unit.HasWeight;
                item.Dimensions.Unit.HasWidth = requiItemShell.Dimensions.Unit.HasWidth;

                item.Dimensions.Quantity = requiItemShell.Dimensions.Quantity;
                item.Dimensions.Length = requiItemShell.Dimensions.Length;
                item.Dimensions.Height = requiItemShell.Dimensions.Height;
                item.Dimensions.Weight = requiItemShell.Dimensions.Weight;
                item.Dimensions.Width = requiItemShell.Dimensions.Width;

                item.Dimensions.Unit.Format = requiItemShell.Dimensions.Unit.Format;
                item.Dimensions.Unit.Formula = requiItemShell.Dimensions.Unit.Formula;

                item.Dimensions.UnitSize = requiItemShell.Dimensions.UnitSize;

                toSave.Add(item);
            }
            DoSaveRequiItems(toSave);
        }

        private void DoDeleteRequiItems(List<RequisitionItem> toDelete)
        {
            try
            {
                new Client<RequisitionItem>().Delete(toDelete, "Updated from mobile device");
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                DoDeleteRequiItems(toDelete);
            }
        }

        private void DoSaveRequiItems(List<RequisitionItem> toSave)
        {
            try
            {
                new Client<RequisitionItem>().Save(toSave, "Saved requi on mobile device");
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                DoSaveRequiItems(toSave);
            }
        }

        private void SavePhotos()
        {
            Task.Run(() =>
            {
                if (imagesDocuments.Count != 0)
                {
                    DoSaveDocuments();
                    List<RequisitionDocument> newRequiDocuments = new List<RequisitionDocument>();
                    foreach (Document doc in imagesDocuments.Values)
                    {
                        var requiDocument = new RequisitionDocument();
                        requiDocument.EntityLink.ID = requisition.ID;
                        requiDocument.DocumentLink.ID = doc.ID;
                        requiDocument.DocumentLink.FileName = doc.FileName;
                        newRequiDocuments.Add(requiDocument);
                    }
                    DoSaveRequiDocuments(newRequiDocuments);
                }
            });
        }

        private void DoSaveDocuments()
        {
            try
            {
                new Client<Document>().Save(imagesDocuments.Values, "Photo Taken on Mobile device Requis module");
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                DoSaveDocuments();
            }
        }

        private void DoSaveRequiDocuments(List<RequisitionDocument> newRequiDocuments)
        {
            try
            {
                new Client<RequisitionDocument>().Save(newRequiDocuments, "Photo Taken on Mobile device Requis module");
            }
            catch (Exception ex)
            {
                InABox.Mobile.MobileLogging.Log(ex);
                DoSaveRequiDocuments(newRequiDocuments);
            }
        }

        private bool CheckSaveOk()
        {
            bool bOK = false;
            if (requisition.JobLink.ID != Guid.Empty)
            {
                bOK = true;
            }
            else
            {
                DisplayAlert("Unable to save", "Add a Job", "OK");
                return bOK;
            }

            if (images.Children.Count > 0)
            {
                bOK = true;
            }
            else if (isNewRequest)
            {
                bOK = true;
            }
            else
            {
                bOK = false;
                DisplayAlert("Unable to save", "Add a Photo", "OK");
                return bOK;
            }

            return bOK;
        }
        #endregion
    }
}