using System.Collections.Generic;
using System.IO;
using System.Linq;
using InABox.Core;
using InABox.Mobile;
using Xamarin.Forms;

namespace PRS.Mobile
{
    public class DigitalFormMultiImage : MobileCard, IDigitalFormField<DFLayoutMultiImage, DFLayoutMultiImageProperties, DFLayoutEmbeddedMediaValues> 
    {
        private readonly CollectionView _images;
        
        private DFLayoutMultiImage _definition;
        public DFLayoutMultiImage Definition
        {
            get => _definition;
            set
            {
                _definition = value;
                Initialize(value ?? new DFLayoutMultiImage());
            }
        }
        
        private DFLayoutEmbeddedMediaValues _value = new DFLayoutEmbeddedMediaValues();
        public DFLayoutEmbeddedMediaValues Value
        {
            get => _value;
            set
            {
                _value = value;
                DoUpdateUI();
            }
        }

        public bool IsEmpty => Value?.Any() != true;
        
        private void DoUpdateUI()
            => _images.ItemsSource = _value.Select(x => ImageSource.FromStream(() => new MemoryStream(x.Data)));

        private bool _readOnly;
        public bool ReadOnly
        {
            get => _readOnly;
            set
            {
                _readOnly = value;
                UpdateStatus();
            }
        }
        
        public void Deserialize(string serialized)
        {
            _value = new DFLayoutEmbeddedMediaValues(serialized);
            _value.PropertyChanged += (sender, args) => DoUpdateUI();
            DoUpdateUI();
        }

        public string Serialize()
        {
            return _value?.ToString() ?? "";
        }
        
        public event DigitalFormViewChangedHandler ValueChanged;

        public DigitalFormMultiImage()
        {
            _value = new DFLayoutEmbeddedMediaValues();
            _value.PropertyChanged += (sender, args) => DoUpdateUI();
            
            HeightRequest = 200;
            Padding = 5;
            Grid grid = new Grid();

            grid.ColumnDefinitions.Add(new ColumnDefinition() { Width = GridLength.Star });
            grid.ColumnDefinitions.Add(new ColumnDefinition() { Width = GridLength.Star });
            
            grid.RowDefinitions.Add(new RowDefinition() { Height = GridLength.Star });
            grid.RowDefinitions.Add(new RowDefinition() { Height = GridLength.Auto });
            
            _images = new CollectionView
            {
                ItemsLayout = new LinearItemsLayout(ItemsLayoutOrientation.Horizontal),
                BackgroundColor = Color.Red,
                ItemTemplate = new DataTemplate(() =>
                {
                    var image = new Image();
                    return image;
                })
            };
            _images.SetValue(Grid.RowProperty,0);
            _images.SetValue(Grid.ColumnProperty,0);
            _images.SetValue(Grid.ColumnSpanProperty,2);
            grid.Children.Add(_images);
            
            MobileButton camera = new MobileButton()
            {
                Image = ImageSource.FromFile("camera"),
                Text = "Take Photo",
                Orientation = StackOrientation.Horizontal
            };
            camera.Clicked += (sender, args) =>
            {

            };
            camera.SetValue(Grid.RowProperty,1);
            camera.SetValue(Grid.ColumnProperty,0);
            grid.Children.Add(camera);
            
            MobileButton library = new MobileButton()
            {
                Image = ImageSource.FromFile("gallery"),
                Text = "Library",
                Orientation = StackOrientation.Horizontal
            };
            library.Clicked += (sender, args) =>
            {

            };
            library.SetValue(Grid.RowProperty,1);
            library.SetValue(Grid.ColumnProperty,1);
            grid.Children.Add(library);
            
            Content = grid;
        }
        
        private void Initialize(DFLayoutMultiImage value)
        {
            UpdateStatus();
        }

        private void UpdateStatus()
        {
            
        }
    }
}