using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Globalization;
using System.Linq;
using Comal.Classes;
using InABox.Clients;
using InABox.Core;
using InABox.Mobile;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using XF.Material.Forms.UI.Dialogs;

namespace PRS.Mobile
{
    
    public class ExistingFormStatusConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value is IDigitalFormInstanceShell shell)
            {
                return !shell.Completed.IsEmpty()
                    ? $"{shell.Completed:dd MMMM yy}"
                    : !shell.Started.IsEmpty()
                        ? $"{shell.Started:dd MMMM yy}"
                        : $"{shell.Created:dd MMMM yy}";
            }
            return "";
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
    
    public class ExistingFormBackgroundColorConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value is IDigitalFormInstanceShell shell)
            {
                return !shell.Completed.IsEmpty()
                    ? Color.DimGray
                    : !shell.Started.IsEmpty()
                        ? Color.LightGreen
                        : Color.Coral;
            }
            return Color.Transparent;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
    
    public class ExistingFormForegroundColorConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value is IDigitalFormInstanceShell shell)
            {
                return !shell.Completed.IsEmpty()
                    ? Color.WhiteSmoke
                    : !shell.Started.IsEmpty()
                        ? Color.Black
                        : Color.Black;
            }
            return Color.Transparent;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
    
    public class ExistingFormRefreshEventArgs : CancelEventArgs
    {
    }
    
    public delegate void ExistingFormRefreshEvent(object sender, ExistingFormRefreshEventArgs args);
    
    public class ExistingFormSearchEventArgs : EventArgs
    {
        public IDigitalFormInstanceShell Shell { get; private set; }

        public ExistingFormSearchEventArgs(IDigitalFormInstanceShell shell)
        {
            Shell = shell;
        }
    }
    public delegate bool ExistingFormSearchEvent(object sender, ExistingFormSearchEventArgs args);
    
        
    public class ExistingFormTappedEventArgs : EventArgs
    {
        public IDigitalFormInstanceShell Shell { get; private set; }

        public ExistingFormTappedEventArgs(IDigitalFormInstanceShell shell)
        {
            Shell = shell;
        }
    }
    public delegate void ExistingFormTappedEvent(object sender, ExistingFormTappedEventArgs args);
    
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class ExistingForms
    {
        
        private String _currentfilter = "";

        public ICoreRepository DataModel
        {
            get => _model.DataModel;
            set => _model.DataModel = value;
        }

        public String AppliesTo
        {
            get => _model.AppliesTo;
            set => _model.AppliesTo = value;
        }

        public Func<ICoreRepository, IDigitalFormInstanceShell[]> Property
        {
            get => _model.Property;
            set => _model.Property = value;
        }

        public bool SeparateHistory
        {
            get => _model.SeparateHistory;
            set => _model.SeparateHistory = value;
        }
        
        public bool PullToRefresh
        {
            get => _model.PullToRefresh;
            set => _model.PullToRefresh = value;
        }

        public event ExistingFormRefreshEvent RefreshRequested;
        public event ExistingFormSearchEvent Search;
        public event ExistingFormTappedEvent FormTapped;
        
        // Event to handle new / existing form selection
        
        public ExistingForms()
        {
            InitializeComponent();
        }
        
        public void RefreshData(bool force, bool async)
        {
            if (async)
                DataModel?.Refresh(force, Refresh);
            else
            {
                DataModel?.Refresh(force);
                Refresh();
            }
        }

        public void Refresh()
        {
            var forms = Property(DataModel);
            Device.BeginInvokeOnMainThread(() =>
            {
                _forms.LastUpdated = DataModel?.LastUpdated ?? DateTime.MinValue;
                _forms.ItemsSource = forms?
                    .Where(FilterShell)
                    .OrderByDescending(SortShell)
                    .ToList();
            });
        }

        private DateTime SortShell(IDigitalFormInstanceShell shell)
        {
            return !shell.Completed.IsEmpty()
                ? shell.Completed
                : !shell.Started.IsEmpty()
                    ? shell.Started
                    : shell.Created;
        }
        
        private bool _showincomplete = true;
        
        private bool FilterShell(IDigitalFormInstanceShell shell)
        {
            if (_model.SeparateHistory)
            {
                bool shellincomplete = shell.Completed.IsEmpty();
                if (shellincomplete != _showincomplete)
                    return false;
            }

            bool bOK = 
                String.IsNullOrWhiteSpace(_currentfilter) 
                || (shell.FormCode.ToUpper().Contains(_currentfilter.ToUpper()) 
                || shell.FormDescription.ToUpper().Contains(_currentfilter.ToUpper()));
            
            bOK = bOK 
                && (Search?.Invoke(this, new ExistingFormSearchEventArgs(shell)) ?? true);
            
            return bOK;
        }

        private void _search_OnTextChanged(object sender, MobileSearchBarTextChangedArgs args)
        {
            _currentfilter = args.Text;
            Refresh();
        }

        private void _digitalforms_OnRefresh(object sender, MobileListRefreshEventArgs args)
        {
            var newargs = new ExistingFormRefreshEventArgs() { Cancel = false };
            RefreshRequested?.Invoke(this, newargs);
            if (!newargs.Cancel)
                RefreshData(true,false);
        }
        
        private void AddForm_Tapped(object sender, EventArgs e)
        {
            var selector = new NewForms() { AppliesTo = this.AppliesTo };
            selector.ItemSelected += CreateNewForm;
            Navigation.PushAsync(selector);
        }

        private async void CreateNewForm(object sender, NewFormSelectedArgs args)
        {
            await MaterialDialog.Instance.AlertAsync("Not Implemented Yet!");
            return;
        }


        private async void Form_Clicked(object sender, EventArgs e)
        {
            if ((sender is MobileCard card) && (card.BindingContext is IDigitalFormInstanceShell shell))
                FormTapped?.Invoke(this, new ExistingFormTappedEventArgs(shell));
            else
                await MaterialDialog.Instance.AlertAsync("Tapped Item is not a Digital Form", "ERROR");
        }
        
        public void CreateNewForm(String appliesto, Func<IDigitalFormInstanceShell> createform, Guid parentid, Action refresh)
        {
            var selector = new NewForms() { AppliesTo = appliesto };
            selector.ItemSelected += (sender, args) =>
            {
                var instance = createform();
                instance.ParentID = parentid;
                instance.FormID = args.Form.ID;
                instance.FormCode = args.Form.Code;
                instance.FormDescription = args.Form.Description;
                instance.Save("Created on Mobile Device");
                Dispatcher.BeginInvokeOnMainThread(refresh);
            };
            Navigation.PushAsync(selector);
        }
        
        public void EditForm<TParent, TParentLink, TForm>(IDigitalFormInstanceShell shell, TParent parent) 
            where TParent : Entity, IRemotable, IPersistent, new()
            where TParentLink : EntityLink<TParent>, new()
            where TForm : Entity, IRemotable, IPersistent, IDigitalFormInstance<TParentLink>, new()
        {
            
            var table = new Client<TForm>().Query(
                new Filter<TForm>(x => x.ID).IsEqualTo(shell.ID),
                new Columns<TForm>(ColumnTypeFlags.None).Add(x=>x.ID).Add(x=>x.Form.ID)
            );
            var form = table.Rows
                .Select(x => x.ToObject<TForm>())
                .FirstOrDefault();
            
            var model = new DigitalFormHostModel<TParent, TParentLink, TForm>();
            model.LoadItems(
                parent, 
                form.Form.ID,
                form.ID,
                null);
            var host = new DigitalFormHost(model);

            host.OnClosing += (o, args) =>
            {
                if (args.Changed)
                {
                    RefreshData(true,true);
                    //instance.Completed = !model.DigitalFormDataModel.Instance.FormCompleted.IsEmpty();
                }
            };
            Navigation.PushAsync(host);
            
        }
        
        public async void EditFormAsync<TParent, TParentLink, TForm>(IDigitalFormInstanceShell shell, TParent parent) 
            where TParent : Entity, IRemotable, IPersistent, new()
            where TParentLink : EntityLink<TParent>, new()
            where TForm : Entity, IRemotable, IPersistent, IDigitalFormInstance<TParentLink>, new()
        {
            
            using (await MaterialDialog.Instance.LoadingDialogAsync(message: "Loading"))
            {

                var form = new Client<TForm>()
                    .Query(
                        new Filter<TForm>(x => x.ID).IsEqualTo(shell.ID),
                        new Columns<TForm>(ColumnTypeFlags.None).Add(x=>x.ID).Add(x=>x.Form.ID)
                        )
                    .Rows
                    .Select(x => x.ToObject<AssignmentForm>())
                    .FirstOrDefault();
                
                var model = new DigitalFormHostModel<TParent, TParentLink, TForm>();
                model.LoadItems(parent, form.Form.ID, form.ID, null);
                var host = new DigitalFormHost(model);

                host.OnClosing += (o, args) =>
                {
                    if (args.Changed)
                    {
                        RefreshData(true,true);
                        //instance.Completed = !model.DigitalFormDataModel.Instance.FormCompleted.IsEmpty();
                    }
                };
                Navigation.PushAsync(host);
            }
            
        }

        private void _tabStrip_OnSelectionChanged(object sender, EventArgs e)
        {
            _showincomplete = _tabStrip.SelectedItem?.Index == 0;
            _model.DataModel.SelectNone();
            _selectionmenubutton.IsVisible = false;
            Refresh();
        }

        private void _selectionmenu_OnAppearing(object sender, EventArgs e)
        {
            _completeform.IsVisible = _showincomplete;
            _reopenform.IsVisible = !_showincomplete;
            //bool anyselected = SelectedItems().Any();
            //bool anyunselected = UnselectedItems().Any();

            //_setstatus.IsVisible = anyselected;
            //_selectAll.IsVisible = anyunselected;
            //_selectNone.IsVisible = anyselected;
            //_separator.IsVisible = (_setstatus.IsVisible) && (_selectAll.IsVisible || _selectNone.IsVisible);

        }

        private IEnumerable<IShell> SelectedItems()
        {
            return _model.DataModel.SelectedItems.OfType<IShell>();
        }
        
        private IEnumerable<IShell> UnselectedItems()
        {
            return _model.DataModel.Items.OfType<IShell>().Except(_model.DataModel.SelectedItems.OfType<IShell>());
        }

        private void _setstatus_OnClicked(object sender, EventArgs e)
        {
            
        }

        private void _selectAll_OnClicked(object sender, EventArgs e)
        {
            _model.DataModel.SelectAll();
            RefreshData(false,false);
        }

        private void _selectNone_OnClicked(object sender, EventArgs e)
        {
            _model.DataModel.SelectNone();
            RefreshData(false,false);
        }

        private void CheckBox_Changed(object sender, EventArgs e)
        {
            if ((sender as MobileCheckBox)?.BindingContext is IShell shell)
                _model.DataModel.ToggleSelection(shell);
            _selectionmenubutton.IsVisible = SelectedItems().Any();
        }

        private void _completeform_OnClicked(object sender, EventArgs e)
        {
            var shells = _model.DataModel.SelectedItems.OfType<IDigitalFormInstanceShell>().ToArray();
            foreach (var shell in shells)
            {
                shell.Completed = DateTime.Now;
                shell.Save("Completed on Mobile Device");
            }
            _model.DataModel.SelectNone();
            _selectionmenubutton.IsVisible = false;
            RefreshData(true,false);
        }

        private void _reopenform_OnClicked(object sender, EventArgs e)
        {
            var shells = _model.DataModel.SelectedItems.OfType<IDigitalFormInstanceShell>().ToArray();
            foreach (var shell in shells)
            {
                shell.Completed = DateTime.MinValue;
                shell.Save("Re-Opened on Mobile Device");
            }
            _model.DataModel.SelectNone();
            _selectionmenubutton.IsVisible = false;
            RefreshData(true,false);
        }
    }
}