using BBWY.Client.APIServices;
using BBWY.Client.Models;
using GalaSoft.MvvmLight.Command;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Input;
using BBWY.Common.Extensions;

namespace BBWY.Client.ViewModels
{
    public class BatchPurchaseAddProductSkuViewModel : BaseVM
    {
        private BatchPurchaseService batchPurchaseService;
        private bool isLoading;
        private string sku;
        private string spu;
        private Purchaser selectedPurchaser;
        private Purchaser defaultPurchaser;

        private KVModel selectedPurchasePlatform;
        private KVModel defaultPurchasePlatform;

        private bool allSelected;

        public ICommand SearchCommand { get; set; }
        public ICommand FilterCommand { get; set; }
        public ICommand SaveCommand { get; set; }

        public ICommand AddQuantityCommand { get; set; }

        public ICommand SubtractQuantityCommand { get; set; }

        public string Sku { get => sku; set { Set(ref sku, value); } }
        public string Spu { get => spu; set { Set(ref spu, value); } }

        public IList<Purchaser> PurchaserList { get; set; }
        public IList<KVModel> PurchasePlatformList { get; set; }
        public Purchaser SelectedPurchaser
        {
            get => selectedPurchaser; set { Set(ref selectedPurchaser, value); }
        }

        public KVModel SelectedPurchasePlatform
        {
            get => selectedPurchasePlatform; set { Set(ref selectedPurchasePlatform, value); }
        }

        public IList<ProductSkuWithScheme> SourceList { get; set; }
        public IList<ProductSkuWithScheme> FilterList { get; set; }
        public bool IsLoading { get => isLoading; set { Set(ref isLoading, value); } }

        public bool AllSelected
        {
            get => allSelected; set
            {
                if (Set(ref allSelected, value))
                    OnAllSelectedChanged();
            }
        }

        public BatchPurchaseAddProductSkuViewModel(BatchPurchaseService batchPurchaseService)
        {
            this.batchPurchaseService = batchPurchaseService;
            defaultPurchaser = new Purchaser() { Id = "-1", Name = "全部" };
            defaultPurchasePlatform = new KVModel() { Key = "-1", Value = "全部" };

            PurchaserList = new ObservableCollection<Purchaser>() { defaultPurchaser };
            PurchasePlatformList = new ObservableCollection<KVModel>()
            {
                defaultPurchasePlatform,
                new KVModel(){ Key=((int)Platform.拳探).ToString(),Value = Platform.拳探.ToString() },
                new KVModel(){ Key=((int)Platform.阿里巴巴).ToString(),Value = Platform.阿里巴巴.ToString() }
            };

            SourceList = new List<ProductSkuWithScheme>();
            FilterList = new ObservableCollection<ProductSkuWithScheme>();
            SearchCommand = new RelayCommand(Search);
            FilterCommand = new RelayCommand(Filter);
            SaveCommand = new RelayCommand(Save);
            AddQuantityCommand = new RelayCommand<ProductSkuWithScheme>(AddQuantity);
            SubtractQuantityCommand = new RelayCommand<ProductSkuWithScheme>(SubtractQuantity);
            SelectedPurchaser = PurchaserList[0];
            SelectedPurchasePlatform = PurchasePlatformList[0];
        }

        private void Search()
        {
            IsLoading = true;
            Task.Factory.StartNew(() => batchPurchaseService.GetProductSkuAndSchemeList(Sku, Spu)).ContinueWith(t =>
            {
                IsLoading = false;
                var response = t.Result;
                if (!response.Success)
                {
                    App.Current.Dispatcher.Invoke(() => MessageBox.Show(response.Msg, "提示"));
                    return;
                }
                SourceList.Clear();

                App.Current.Dispatcher.Invoke(() =>
                {
                    PurchaserList.Clear();
                    FilterList.Clear();

                    PurchaserList.Add(defaultPurchaser);
                    SelectedPurchaser = PurchaserList[0];
                    SelectedPurchasePlatform = PurchasePlatformList[0];
                });

                if (response.Data == null || response.Data.Count() == 0)
                    return;
                var list = response.Data.Map<IList<ProductSkuWithScheme>>();

                #region 提取采购商
                var purchaserList = list.Where(item => item.PurchaseSchemeId != 0)
                                        .Select(item => new Purchaser() { Id = item.PurchaserId, Name = item.PurchaserName, Platform = item.PurchasePlatform.Value })
                                        .Distinct(new PurchaserComparer());
                #endregion

                App.Current.Dispatcher.Invoke(() =>
                {
                    foreach (var purchaser in purchaserList)
                        PurchaserList.Add(purchaser);
                    foreach (var item in list)
                    {
                        SourceList.Add(item);
                    }
                    Filter();
                });
            });
        }

        private void Filter()
        {
            FilterList.Clear();
            if (SourceList.Count() == 0)
                return;
            var resultList = new List<ProductSkuWithScheme>();
            resultList.AddRange(SourceList);

            if (SelectedPurchaser.Id != "-1")
            {
                for (var i = 0; i < resultList.Count(); i++)
                {
                    if (resultList[i].PurchaserId != SelectedPurchaser.Id)
                    {
                        resultList.Remove(resultList[i]);
                        i--;
                    }
                }
            }

            if (SelectedPurchasePlatform.Key != "-1")
            {
                for (var i = 0; i < resultList.Count(); i++)
                {
                    if (resultList[i].PurchasePlatform != (Platform)int.Parse(SelectedPurchasePlatform.Key))
                    {
                        resultList.Remove(resultList[i]);
                        i--;
                    }
                }
            }

            if (resultList.Count() > 0)
            {
                foreach (var item in resultList)
                    FilterList.Add(item);
            }
        }

        private void Save()
        {
            var selectedList = FilterList.Where(item => item.IsSelected).ToList();
            if (selectedList == null || selectedList.Count() == 0)
            {
                MessageBox.Show("至少选择一个商品");
                return;
            }
            GalaSoft.MvvmLight.Messaging.Messenger.Default.Send(selectedList, "BatchPurchaseAddProductSkuSave");
        }

        private void OnAllSelectedChanged()
        {
            foreach (var item in FilterList)
            {
                if (item.PurchaseSchemeId == 0)
                    continue;
                item.IsSelected = AllSelected;
            }
        }

        private void AddQuantity(ProductSkuWithScheme item)
        {
            item.Quantity++;
        }

        private void SubtractQuantity(ProductSkuWithScheme item)
        {
            if (item.Quantity > 0)
                item.Quantity--;
        }
    }
}