using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Comal.Classes;
using Comal.Classes.SecurityDescriptors;
using InABox.Core;
using InABox.Mobile;
using Xamarin.Essentials;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using XF.Material.Forms.UI.Dialogs;
using Result = ZXing.Result;

namespace PRS.Mobile
{

    public class HoldingUnitCalculator : AbstractConverter<StockHoldingShell, double>
    {

        public RequisitionItemModel RequisitionItems { get; set; }

        protected override double Convert(StockHoldingShell shell, object? parameter = null)
        {
            return Calculate(shell, RequisitionItems);
        }

        public static double Calculate(StockHoldingShell holding, RequisitionItemModel? items)
        {
            var instock = holding.Units;
            var picked = items?.Items.Where(x =>
                x.LocationID == holding.LocationID
                && x.ProductID == holding.ProductID
                && x.StyleID == holding.StyleID
                && x.JobID == holding.JobID
                && x.DimensionsLength == holding.DimensionsLength
                && x.DimensionsWidth == holding.DimensionsWidth
                && x.DimensionsHeight == holding.DimensionsHeight
                && x.DimensionsWeight == holding.DimensionsWeight
                && holding.DimensionsQuantity == x.DimensionsQuantity)
                .Sum(x => x.ActualQuantity) ?? 0.0;
            return instock - picked;
        }
    }

    public class QuickPickViewModel : BindableObject
    {
        public bool HasItems { get; set; }
        public StockHoldingModel Holdings { get; private set; }

        public void RefreshHoldings(bool force, Guid barcode)
        {
            Holdings.Refresh(true, () =>
            {
                IsLocation = Holdings.Items.Select(x => x.LocationID).All(x => x == barcode);
                IsProduct = Holdings.Items.Select(x => x.ProductID).All(x => x == barcode);
                
            });
        }
        
        public bool IsLocation { get; private set; }
        public bool IsProduct { get; private set; }

        public string Title => IsLocation
            ? $"{Holdings.Items.FirstOrDefault()?.LocationCode} - {Holdings.Items.FirstOrDefault()?.LocationDescription}"
            : IsProduct
                ? $"{Holdings.Items.FirstOrDefault()?.ProductCode} - {Holdings.Items.FirstOrDefault()?.ProductName}"
                : "Scan Barcode";
        
        public RequisitionItemModel RequisitionItems { get; private set; }
        
        public JobShell Job { get; set; }
        
        public QuickPickViewModel()
        {
            Holdings = new StockHoldingModel(App.Data, () => new Filter<StockHolding>().None());
            RequisitionItems = new RequisitionItemModel(App.Data, () => new Filter<RequisitionItem>().None());
            Job = App.Data.Jobs.CreateItem();
        }
    }
    
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class QuickPickModule : MobilePage
    {
        public QuickPickModule()
        {
            InitializeComponent();
            UnitCalculator.RequisitionItems = _viewModel.RequisitionItems;
            var options = new ZXing.Mobile.MobileBarcodeScanningOptions()
            {
                PossibleFormats = new List<ZXing.BarcodeFormat>() { ZXing.BarcodeFormat.QR_CODE },
                AutoRotate = false,
                TryInverted = true,
                TryHarder = true,
            };
            _scanView.Options = options;
            _scanView.IsAnalyzing = false;
            _scanView.IsScanning = true;
        }

        protected override void OnAppearing()
        {
            base.OnAppearing();
            try
            {
                _scanView.IsAnalyzing = _tabStrip.SelectedIndex == 0;
            }
            catch (Exception e)
            {
                InABox.Mobile.MobileLogging.Log(e);
            }
        }
        
        protected override void OnDisappearing()
        {
            
            try
            {
                _scanView.IsAnalyzing = false;
            }
            catch (Exception e)
            {
                InABox.Mobile.MobileLogging.Log(e);
            }
            base.OnDisappearing();
        }
        
        private void _tabStrip_OnSelectionChanged(object sender, EventArgs e)
        {
            _scanView.IsAnalyzing = _tabStrip.SelectedIndex == 0;
            _viewModel.HasItems = _viewModel.RequisitionItems.Any();
        }
        
        private bool bProcessing = false;
        private Guid _lastGuid = Guid.Empty;
        private async void ScanView_OnScanResult(ZXing.Result result)
        {
            if (bProcessing)
                return;

            if (!Guid.TryParse(result.Text, out Guid id) || id == Guid.Empty || id == _lastGuid)
                return;

            _lastGuid = id;
            
            bProcessing = true;
            using (await MaterialDialog.Instance.LoadingDialogAsync($"Processing..."))
            {
                Vibration.Vibrate();
                SearchLocationID(id);
                bProcessing = false;
            }

        }

        private void SearchLocationID(Guid id)
        {
            //App.Data.StockLocations.Refresh(false);
            //var location = App.Data.StockLocations.FirstOrDefault(x => Guid.Equals(x.ID,id));
            //if (location != null)
            //{
                _viewModel.Holdings.Filter = () =>
                    new Filter<StockHolding>(x => x.Location.ID).IsEqualTo(id).Or(x=>x.Product.ID).IsEqualTo(id);
                _viewModel.RefreshHoldings(true, id);
                //}
        }
        
        private void SelectFromHolding_Click(object sender, EventArgs e)
        {
            var holding = (sender as MobileCard)?.BindingContext as StockHoldingShell;
            if (holding == null)
                return;
            ShowPopup(() =>
                {

                    var qty = HoldingUnitCalculator.Calculate(holding, _viewModel.RequisitionItems);
                    var editor = new SelectFromHoldingView(holding, qty, _viewModel.RequisitionItems);
                    editor.OnSave += (o, args) =>
                    {
                        if (!args.Quantity.IsEffectivelyEqual(0.0))
                        {
                            var requiItem = _viewModel.RequisitionItems.CreateItem();
                            requiItem.LocationID = args.Holding.LocationID;
                            requiItem.ProductID = args.Holding.ProductID;
                            requiItem.ProductCode = args.Holding.ProductCode;
                            requiItem.ProductName = args.Holding.ProductName;
                            requiItem.StyleID = args.Holding.StyleID;
                            requiItem.StyleCode = args.Holding.StyleCode;
                            requiItem.StyleDescription = args.Holding.StyleDescription;
                            requiItem.JobID = args.Holding.JobID;
                            requiItem.DimensionsUnitID = args.Holding.DimensionsUnitID;
                            requiItem.DimensionsHeight = args.Holding.DimensionsHeight;
                            requiItem.DimensionsWidth = args.Holding.DimensionsWidth;
                            requiItem.DimensionsLength = args.Holding.DimensionsLength;
                            requiItem.DimensionsQuantity = args.Holding.DimensionsQuantity;
                            requiItem.DimensionsWeight = args.Holding.DimensionsWeight;
                            requiItem.DimensionsValue = args.Holding.DimensionsValue;
                            requiItem.DimensionsUnitSize = args.Holding.DimensionsUnitSize;
                            requiItem.ImageID = args.Holding.ImageID;
                            if (args.Holding.Parent.Images.TryGetValue(args.Holding.ImageID, out var _image))
                                _viewModel.RequisitionItems.Images[args.Holding.ImageID] = _image;
                            requiItem.SourceJRI = args.JobRequisitionItemID;
                            requiItem.TargetJRI = args.JobRequisitionItemID;
                            requiItem.Quantity = args.Quantity;
                            requiItem.ActualQuantity = args.Quantity;
                            requiItem.Cost = args.Holding.AverageCost;
                            requiItem.Done = true;
                            _viewModel.RequisitionItems.CommitItem(requiItem);
                            _viewModel.Holdings.Refresh(false);
                            DismissPopup();
                        }
                    };
                    editor.OnCancel += (o, args) => DismissPopup();
                    return editor;
                },
                new PopupManagerConfiguration()
                {
                    RequestedHeight = Math.Min(700,500 + (holding.Allocations.Length * 55))
                });
        }
        
        private void SelectJob_Clicked(object sender, MobileButtonClickEventArgs args)
        {
            ShowPopup(() => SelectionView.Execute<JobShell>(
                (columns) =>
                {
                    columns.Add(new MobileGridTextColumn<JobShell>()
                    {
                        Column = x => x.JobNumber, 
                        Width = GridLength.Auto, 
                        Caption = "#",
                        Alignment = TextAlignment.Center
                    });
                    columns.Add(new MobileGridTextColumn<JobShell>()
                    {
                        Column = x => x.Name,
                        Width = GridLength.Star,
                        Caption = "Select Job",
                        Alignment = TextAlignment.Start
                    });
                },
                (refresh) => App.Data.Jobs.Refresh(false), 
                (jobs) =>
                {
                    _viewModel.Job = jobs.FirstOrDefault() ?? App.Data.Jobs.CreateItem();
                    DismissPopup();
                }));

        }

        private async void SaveList_Click(object sender, MobileMenuButtonClickedEventArgs args)
        {
            if (_viewModel.Job.ID == Guid.Empty && !Security.IsAllowed<AllowMobileQuickPickWithoutJob>())
            {
                await MaterialDialog.Instance.AlertAsync("Please select a Job before saving!", "Error");
                return;
            }
            
            using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Saving"))
            {
                try
                {
                    var _requiModel = new RequisitionModel(App.Data, () => new Filter<Requisition>().None());
                    var requi = _requiModel.CreateItem();
                    requi.Title = $"Quick Pick by {App.Data.Me.Name}";
                    requi.RequestedByID = App.Data.Me.ID;
                    requi.Due = DateTime.Now;
                    requi.JobID = _viewModel.Job.ID;
                    _requiModel.CommitItem(requi);
                    _requiModel.Save("Requisition Created from Mobile Quick Pick Module");
                    foreach (var _item in _viewModel.RequisitionItems.Items)
                    {
                        if (_viewModel.Job.ID != _item.JobID)
                            _item.TargetJRI = Guid.Empty;
                        
                        // This should stop the multi-transaction thingy if returning items to stock
                        if (_item.Quantity.IsEffectivelyLessThan(0.0))
                            _item.JobID = requi.JobID;
                        
                        _item.RequisitionID = requi.ID;
                    }

                    _viewModel.RequisitionItems.Save("Created from Mobile Quick Pick Module");
                    requi.Filled = requi.Due;
                    requi.StockUpdated = requi.Filled;
                    _requiModel.Save("Stock Movements created from Mobile Quick Pick Module");
                }
                catch (Exception e)
                {
                    InABox.Mobile.MobileLogging.Log(e);
                }
            }
            Navigation.PopAsync();
        }

        private async void DeleteRequisitionItem(object sender, MobileMenuButtonClickedEventArgs args)
        {
            var shell = ((sender as MobileMenuButton)?.BindingContext as RequisitionItemShell);
            if (shell == null)
                return;
            if (await MaterialDialog.Instance.ConfirmAsync("Delete Picked Item?", "Confirm") == true)
            {
                _viewModel.RequisitionItems.DeleteItem(shell);
            }
        }

        private void AddHolding_Clicked(object sender, MobileMenuButtonClickedEventArgs args)
        {
            var first = _viewModel.Holdings.FirstOrDefault();
            if (first == null)
                return;
            var holding = _viewModel.Holdings.CreateItem();
            holding.LocationID = first.LocationID;
            holding.LocationCode = first.LocationCode;
            holding.LocationDescription = first.LocationDescription;
            
            var transaction = new StockTransaction(StockTransactionType.StockTake, holding, holding);
            transaction.Allocations = new StockTransactionAllocation[]
            {
                new StockTransactionAllocation()
                {
                    ID = Guid.Empty,
                    Description = "General Stock",
                    Quantity = 0.0F,
                    Maximum = double.MaxValue
                }
            };
            
            var popup = new StockTakeEdit(transaction);
            popup.TransactionSaved += (o,e) =>
            {
                holding.ProductID = transaction.ProductID;
                holding.ProductCode = transaction.ProductCode;
                holding.ProductName = transaction.ProductName;
                
                holding.DimensionsUnitID = transaction.DimensionsUnitID;
                
                holding.DimensionsHeight = transaction.DimensionsHeight;
                holding.DimensionsWidth = transaction.DimensionsWidth;
                holding.DimensionsLength = transaction.DimensionsLength;
                holding.DimensionsQuantity = transaction.DimensionsQuantity;
                holding.DimensionsWeight = transaction.DimensionsWeight;
                holding.DimensionsValue = transaction.DimensionsValue;
                holding.DimensionsUnitSize = transaction.DimensionsUnitSize;
                
                holding.StyleID = transaction.Target.StyleID;
                holding.StyleCode = transaction.Target.StyleCode;
                holding.StyleDescription = transaction.Target.StyleDescription;
                
                holding.JobID = transaction.Target.JobID;
                holding.JobNumber = transaction.Target.JobNumber;
                holding.JobName = transaction.Target.JobName;
                holding.AverageCost = transaction.Cost;
                //holding.Units = transaction.Quantity;
                
                _viewModel.Holdings.CommitItem(holding);
                
                var requiItem = _viewModel.RequisitionItems.CreateItem();
                
                requiItem.LocationID = holding.LocationID;
                requiItem.ProductID = holding.ProductID;
                requiItem.ProductCode = holding.ProductCode;
                requiItem.ProductName = holding.ProductName;
                requiItem.StyleID = holding.StyleID;
                requiItem.StyleCode = holding.StyleCode;
                requiItem.StyleDescription = holding.StyleDescription;
                requiItem.JobID = holding.JobID;
                requiItem.DimensionsUnitID = holding.DimensionsUnitID;
                requiItem.DimensionsHeight = holding.DimensionsHeight;
                requiItem.DimensionsWidth = holding.DimensionsWidth;
                requiItem.DimensionsLength = holding.DimensionsLength;
                requiItem.DimensionsQuantity = holding.DimensionsQuantity;
                requiItem.DimensionsWeight = holding.DimensionsWeight;
                requiItem.DimensionsValue = holding.DimensionsValue;
                requiItem.DimensionsUnitSize = holding.DimensionsUnitSize;
                requiItem.ImageID = holding.ImageID;
                if (holding.Parent.Images.TryGetValue(holding.ImageID, out var _image))
                    _viewModel.RequisitionItems.Images[holding.ImageID] = _image;
                requiItem.SourceJRI = Guid.Empty;
                requiItem.TargetJRI = Guid.Empty;
                requiItem.Quantity = 0 - transaction.Quantity;
                requiItem.ActualQuantity = 0 - transaction.Quantity;
                requiItem.Cost = transaction.Cost;
                requiItem.Done = true;
                _viewModel.RequisitionItems.CommitItem(requiItem);
                
                _viewModel.Holdings.Refresh(false);
                DismissPopup();
            };
            Navigation.PushAsync(popup);
            
        }
    }
}