AIKKEY_WPFWin7/ViewModels/HomePage/HomePageViewModel.cs

using AIK.Common.Interface;
using AIK.Models.BannerModels;
using AIK.Service.IService;
using AIK.Service.Service;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media.Imaging;
using System.Windows.Threading;

namespace AIK.ViewModels.HomePage
{
    public partial class HomePageViewModel : ObservableObject
    {
        private readonly DispatcherTimer _timer;

        [ObservableProperty]
        [NotifyPropertyChangedFor(nameof(IsFirst))]
        [NotifyPropertyChangedFor(nameof(IsLast))]
        private int _currentIndexPublic = -1;
        public bool IsFirst => CurrentIndexPublic == 0;
        [ObservableProperty]
        private string _currentImagePath;
        [ObservableProperty]
        private BitmapImage _currentBitmapImage;
        public bool IsLast => Banners.Count > 0 && CurrentIndexPublic == Banners.Count - 1;

        public ObservableCollection<BannerItem> Banners { get; } = new ObservableCollection<BannerItem>();

        private readonly IConfigurationService _configurationService;
        private readonly IQRCodeService _qRCodeService;
        //国内版
        private  string defaultLogoPath = "AIK.Assets.Images.AIKChina.png";
        //国外版
        //private const string defaultLogoPath = "AIK.Assets.Images.AIKInternationl.png";
        [ObservableProperty]
        private byte[]? _qrCodeBytes; // 👈 只暴露字节数组

        private readonly IAikDataService _aikDataService;
        private readonly IImageCacheService _imageCacheService;
        public HomePageViewModel(IConfigurationService configurationService, IQRCodeService qRCodeService, IAikDataService aikDataService, IImageCacheService imageCacheService)
        {
#if CN
            defaultLogoPath = "AIK.Assets.Images.AIKChina.png";
#elif TEST
            defaultLogoPath = "AIK.Assets.Images.AIKChina.png";
#else
            defaultLogoPath = "AIK.Assets.Images.AIKInternationl.png";
#endif
            _configurationService = configurationService;
            _qRCodeService = qRCodeService;
            _aikDataService = aikDataService;
            _imageCacheService = imageCacheService;
            //LoadLocalBanners();
            _ = LoadRemoteBanners();
            LoadQrCodeImage();
            if (Banners.Count > 0)
            {
                CurrentIndexPublic = 0;
            }
            _timer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(5) };
            _timer.Tick += OnTimerTick;
            _timer.Start();

        }
        partial void OnCurrentIndexPublicChanged(int value)
        {
            if (Banners.Count == 0) return;

            // 边界保护
            if (value < 0 || value >= Banners.Count) return;

            for (int i = 0; i < Banners.Count; i++)
            {
                Banners[i].IsSelected = (i == value);
                if (Banners[i].IsSelected)
                {
                    CurrentImagePath = Banners[i].ImagePath!;
                    CurrentBitmapImage = Banners[i].BitmapImage!;
                }

            }

            //_timer.Stop();
            //_timer.Start(); // 重置自动轮播
        }

        private void LoadQrCodeImage()
        {
            QrCodeBytes = _qRCodeService.GenerateQRCodeWithLogo(_configurationService.ApiSettings.QRCodeUrl, defaultLogoPath, 12);
        }
        private void LoadLocalBanners()
        {
            // 修改为你的实际图片文件夹路径（相对路径）
            string imageFolder = @"C:\Users\23231\Desktop\Images";

            if (!Directory.Exists(imageFolder)) return;

            var validExtensions = new[] { ".jpg", ".jpeg", ".png", ".bmp", ".gif" };
            var imageFiles = Directory.GetFiles(imageFolder)
                                      .Where(f => validExtensions.Contains(Path.GetExtension(f).ToLowerInvariant()))
                                      .OrderBy(f => f) // 可按需排序
                                      .ToList();

            for (int i = 0; i < imageFiles.Count; i++)
            {
                try
                {
                    Banners.Add(new BannerItem { ImagePath = imageFiles[i], Index = i });
                }
                catch (Exception ex)
                {
                    // 可记录日志或跳过损坏图片
                    System.Diagnostics.Debug.WriteLine($"Failed to load image {imageFiles[i]}: {ex.Message}");
                }
            }
        }

        private async Task LoadRemoteBanners()
        {
            try
            {
                var bannerlist = await _aikDataService.GetBannerCache();
                //var bannerlist = await _aikDataService.GetBanner();
                int i = 0;
                foreach (var item in bannerlist)
                {
                    if (!string.IsNullOrEmpty(item.ImgUrl))
                    {
                        var start = DateTime.Now;
                        var localbitmapImage = await _imageCacheService.GetImageByLocalPathAsync(item.ImgUrl);
                        Banners.Add(new BannerItem { BitmapImage = localbitmapImage, ImagePath = item.ImgUrl, Index = i++ });
                        var loaded = DateTime.Now;
                        Debug.WriteLine($"Loaded: {(loaded - start).TotalMilliseconds}ms");
                    }
                }
            }
            catch (Exception ex)
            {
                // fire-and-forget 任务（_ = LoadRemoteBanners()）必须捕获异常，
                // 否则异常会成为"未观察任务异常"（终结器线程重新抛出，App 记录 Task未观察异常）。
                // Banner 加载失败（如网络/TLS 问题）不应影响主流程。
                Debug.WriteLine($"加载远程Banner失败: {ex.Message}");
            }
        }
        private void OnTimerTick(object? sender, EventArgs e)
        {
            if (Banners.Count == 0) return;
            CurrentIndexPublic = (CurrentIndexPublic + 1) % Banners.Count;
        }

        [RelayCommand]
        private void Previous() => CurrentIndexPublic = (CurrentIndexPublic - 1 + Banners.Count) % Banners.Count;

        [RelayCommand]
        private void Next() => CurrentIndexPublic = (CurrentIndexPublic + 1) % Banners.Count;

        [RelayCommand]
        private void SelectBanner(int index) => CurrentIndexPublic = index;
    }

}