using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Input;
using XLIMS.CONTRACT;
using XLIMS.DATA.Models;
using XLIMS.MVVM.Base;

namespace XLIMS.PSV.ViewModels
{

public class BrowseSerialViewModel : ViewModelBase, IDisposable
    {
        private readonly ILimsService _limsService;
        private int _divisionId;

        private DeviceSet _currentSerial = null;
        private string _search = string.Empty;
        private CancellationTokenSource? _searchCts = null;
        private bool _disposed = false;

        public ObservableCollection<DeviceSet> AllSerial { get; } = new();
        public ICollectionView SerialView { get; }

        public DeviceSet? CurrentSerial
        {
            get => _currentSerial;
            set
            {
                _currentSerial = value;
                OnPropertyChanged();
            }
        }

        public string Search
        {
            get => _search;
            set
            { 
                _search = value;
                DebounceSearch();
                OnPropertyChanged();
            }
        }

        public BrowseSerialViewModel(ILimsService limsService, int divisionId)
        {
            _limsService = limsService;
            _divisionId = divisionId;

            SerialView = CollectionViewSource.GetDefaultView(AllSerial);
            SerialView.Filter = SerialFilter;

            LoadSerialsAsync();
        }

        private async Task LoadSerialsAsync()
        {
            AllSerial.Clear();
            var devList = await _limsService.Devices.GetAllAsync();
            foreach (var dev in devList.Where(e=>e.DivisionId==_divisionId))
            {
                AllSerial.Add(dev);
            }
            SerialView.Refresh();
        }
        private bool SerialFilter(object item)
        {
            if (item is not DeviceSet dev) return false;
            if (string.IsNullOrWhiteSpace(Search)) return true;

            var search = Search.Trim();
            return (dev.Serial?.Contains(search, StringComparison.OrdinalIgnoreCase) == true)
                || (dev.Dpzn?.Contains(search, StringComparison.OrdinalIgnoreCase) == true)
                || (dev.Tip?.Contains(search, StringComparison.OrdinalIgnoreCase) == true)
                || (dev.Name?.Contains(search, StringComparison.OrdinalIgnoreCase) == true);
        }

        private ICommand? _saveCommand = null;
        public ICommand SaveCommand => _saveCommand ??= new RelayCommand(_ => Save(), _ => CurrentSerial != null);

        private void Save()
        {
        }

        private async void DebounceSearch()
        {
            _searchCts?.Cancel();
            _searchCts = new CancellationTokenSource();
            try
            {
                await Task.Delay(300, _searchCts.Token);
                SerialView.Refresh();
            }
            catch (TaskCanceledException) { }
        }

        public void Dispose()
        {
            if (_disposed) return;
            _disposed = true;
            GC.SuppressFinalize(this);
        }
    }


}