using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Input;
using AllBase.Model.MvvmBaseClasses;
using _29WxOrderWpf.Ctrls.Statistics.Models;
using _29WxOrderWpf.Ctrls.Statistics.Services;
using CefSharp;
using _29WxOrderWpf.Commands;

namespace _29WxOrderWpf.Ctrls.Statistics.ViewModels
{
	/// <summary>
	/// 店铺营收统计 - 页面 ViewModel（MVVM）。
	/// 通过 IShopRevenueStatisticsService 调用数据接口；
	/// 接入真实接口时传入自定义实现：new ShopRevenueStatisticsViewModel(你的服务实现)。
	/// </summary>
	public class ShopRevenueStatisticsViewModel : PropertyNotifyObject
	{
		private readonly IShopRevenueStatisticsService _service;

		private ShopRevenueSummary _summary;
		private ObservableCollection<RevenueTrendPoint> _trendData;
		private ObservableCollection<ShopSalesProportionItem> _shopProportionData;
		private ObservableCollection<ShopStatisticsItem> _shopStatistics;
		private ShopOption _selectedShop;
		private string _selectedPlatform;

		public ShopRevenueStatisticsViewModel()
			: this(new ShopRevenueStatisticsService())
		{

		}

		public ShopRevenueStatisticsViewModel(IShopRevenueStatisticsService service)
		{
			_service = service ?? new ShopRevenueStatisticsService();

			TimeRangeOptions = new ObservableCollection<TimeRangeOption>
			{
				new TimeRangeOption { Text = "昨天", Value = "yesterday" },
				new TimeRangeOption { Text = "本周", Value = "week" },
				new TimeRangeOption { Text = "本月", Value = "month" },
				new TimeRangeOption { Text = "最近10天", Value = "last10" },
				new TimeRangeOption { Text = "自定义", Value = "custom" }
			};

			ShopOptions = new ObservableCollection<ShopOption>();

			QueryCommand = new DelegateCommand(async () => await LoadAsync());
			ResetCommand = new DelegateCommand(Reset);

			InitializeAsync();
		}

		#region 查询条件

		/// <summary>时间范围选项</summary>
		public ObservableCollection<TimeRangeOption> TimeRangeOptions { get; }

		/// <summary>选中的时间范围</summary>
		public TimeRangeOption SelectedTimeRange
		{
			get { return this.GetValue(x => x.SelectedTimeRange); }
			set
			{
				this.SetValue(x => x.SelectedTimeRange, value);
				ApplyTimeRange();
				OnPropertyChanged(nameof(IsCustomDateRange));
			}
		}

		/// <summary>是否为自定义时间范围</summary>
		public bool IsCustomDateRange
		{
			get { return SelectedTimeRange != null && SelectedTimeRange.Value == "custom"; }
		}

		/// <summary>开始日期</summary>
		public DateTime StartDate
		{
			get { return this.GetValue(x => x.StartDate); }
			set { this.SetValue(x => x.StartDate, value); }
		}

		/// <summary>结束日期</summary>
		public DateTime EndDate
		{
			get { return this.GetValue(x => x.EndDate); }
			set { this.SetValue(x => x.EndDate, value); }
		}

		/// <summary>店铺选项（含“全部店铺”）</summary>
		public ObservableCollection<ShopOption> ShopOptions { get; }

		/// <summary>选中的店铺</summary>
		public ShopOption SelectedShop
		{
			get { return _selectedShop; }
			set
			{
				_selectedShop = value;
				OnPropertyChanged(nameof(SelectedShop));
			}
		}

		#endregion

		#region 统计结果

		/// <summary>汇总卡片数据</summary>
		public ShopRevenueSummary Summary
		{
			get { return _summary; }
			private set
			{
				_summary = value;
				OnPropertyChanged(nameof(Summary));
			}
		}

		/// <summary>销售趋势数据</summary>
		public ObservableCollection<RevenueTrendPoint> TrendData
		{
			get { return _trendData; }
			private set
			{
				_trendData = value;
				OnPropertyChanged(nameof(TrendData));
			}
		}

		/// <summary>店铺销售占比数据</summary>
		public ObservableCollection<ShopSalesProportionItem> ShopProportionData
		{
			get { return _shopProportionData; }
			private set
			{
				_shopProportionData = value;
				OnPropertyChanged(nameof(ShopProportionData));
			}
		}

		/// <summary>店铺统计表格数据</summary>
		public ObservableCollection<ShopStatisticsItem> ShopStatistics
		{
			get { return _shopStatistics; }
			private set
			{
				_shopStatistics = value;
				OnPropertyChanged(nameof(ShopStatistics));
			}
		}

		/// <summary>是否正在加载</summary>
		public bool IsLoading
		{
			get { return this.GetValue(x => x.IsLoading); }
			set { this.SetValue(x => x.IsLoading, value); }
		}

		#endregion

		#region 命令

		/// <summary>查询命令</summary>
		public ICommand QueryCommand { get; }

		/// <summary>重置命令</summary>
		public ICommand ResetCommand { get; }

		#endregion

		#region 初始化

		private async void InitializeAsync()
		{
			try
			{
				// 店铺选项
				ShopOptions.Add(new ShopOption { AppKey = string.Empty, ShopName = "全部店铺" });
				var shops = await _service.GetShopOptionsAsync();
				foreach (var shop in shops)
					ShopOptions.Add(shop);
				SelectedShop = ShopOptions.FirstOrDefault();

				// 默认时间范围：本月
				SelectedTimeRange = TimeRangeOptions.FirstOrDefault(t => t.Value == "month");
				ApplyTimeRange();

				await LoadAsync();
			}
			catch (Exception)
			{
				// 初始化失败（如接口不可用），页面保持可查询状态；可在此接入日志/提示
			}
		}

		#endregion

		#region 业务逻辑

		/// <summary>根据时间范围选项计算起止日期</summary>
		private void ApplyTimeRange()
		{
			var now = DateTime.Now;
			var today = now.Date;
			var selected = SelectedTimeRange == null ? string.Empty : SelectedTimeRange.Value;
			switch (selected)
			{
				case "yesterday":
					StartDate = today.AddDays(-1);
					EndDate = today.AddDays(-1).AddHours(23).AddMinutes(59).AddSeconds(59);
					break;
				case "week":
					int diff = today.DayOfWeek == DayOfWeek.Sunday ? 6 : (int)today.DayOfWeek - 1;
					StartDate = today.AddDays(-diff);
					EndDate = now;
					break;
				case "month":
					StartDate = new DateTime(today.Year, today.Month, 1);
					EndDate = now;
					break;
				case "last10":
					StartDate = today.AddDays(-9);
					EndDate = now;
					break;
				default:
					// 自定义：保持用户选择的日期不变
					break;
			}
		}

		/// <summary>执行查询，刷新页面所有统计数据</summary>
		private async Task LoadAsync()
		{
			if (StartDate > EndDate)
			{
				var temp = StartDate;
				StartDate = EndDate;
				EndDate = temp;
			}

			IsLoading = true;
			try
			{
				var query = new ShopRevenueStatisticsQuery
				{
					StartDate = StartDate,
					EndDate = EndDate,
					ShopKey = SelectedShop == null ? string.Empty : SelectedShop.AppKey,
				};

				Summary = await _service.GetSummaryAsync(query);

				var trend = await _service.GetSalesTrendAsync(query);
				TrendData = new ObservableCollection<RevenueTrendPoint>(trend);

				var proportion = await _service.GetShopSalesProportionAsync(query);
				ShopProportionData = new ObservableCollection<ShopSalesProportionItem>(proportion);

				var table = await _service.GetShopStatisticsAsync(query);
				ShopStatistics = new ObservableCollection<ShopStatisticsItem>(table);
			}
			catch (Exception)
			{
				// 查询异常：保留上一次数据，可在此接入日志/错误提示
			}
			finally
			{
				IsLoading = false;
			}
		}

		/// <summary>重置查询条件并重新加载</summary>
		private async void Reset()
		{
			SelectedShop = ShopOptions.FirstOrDefault();
			SelectedTimeRange = TimeRangeOptions.FirstOrDefault(t => t.Value == "month");
			ApplyTimeRange();
			await LoadAsync();
		}

		#endregion
	}
}