LSFE/LSFE.MobApp/Models/ProductMaterial.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;

namespace LSFE.MobApp.Models
{
    public class ProductMaterial : INotifyPropertyChanged
    {
        private bool _isDownloaded;
        private bool _isDownloading;
        private double _downloadProgress;

        public Guid ProductTransId { get; set; }
        public int ProductId { get; set; }
        public string? ProductName { get; set; }
        public string? ProductLink { get; set; }
        public string? FileUrl { get; set; }
        public string? FileExtension { get; set; }
        public string IconEmoji => FileExtension?.ToLower() switch
        {
            ".pdf" => "📄",
            ".ppt" or ".pptx" => "📊",
            ".doc" or ".docx" => "📝",
            _ => "📎"
        };

        public bool IsDownloaded
        {
            get => _isDownloaded;
            set
            {
                _isDownloaded = value;
                OnPropertyChanged();
                OnPropertyChanged(nameof(DownloadButtonText));
                OnPropertyChanged(nameof(CanDownload));
            }
        }

        public bool IsDownloading
        {
            get => _isDownloading;
            set
            {
                _isDownloading = value;
                OnPropertyChanged();
                OnPropertyChanged(nameof(CanDownload));
            }
        }

        public double DownloadProgress
        {
            get => _downloadProgress;
            set
            {
                _downloadProgress = value;
                OnPropertyChanged();
            }
        }
        private bool _isChecked;
        public bool IsChecked
        {
            get => _isChecked;
            set
            {
                _isChecked = value;
                OnPropertyChanged();
            }
        }
        public string DownloadButtonText => IsDownloaded ? "✓ Downloaded" : "⬇️ Download";
        public bool CanDownload => !IsDownloading && !IsDownloaded;

        public event PropertyChangedEventHandler PropertyChanged;
        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}