using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using LehrerApp.Sync;
using LehrerApp.Sync.Models;

namespace LehrerApp.Desktop.ViewModels;

public partial class SyncStatusViewModel : ObservableObject
{
    private readonly SyncEngine? _engine;

    [ObservableProperty] private string _statusText = "Kein Server konfiguriert";
    [ObservableProperty] private string _lastSyncText = "";
    [ObservableProperty] private bool _isSyncing;
    [ObservableProperty] private bool _isServerConfigured;
    [ObservableProperty] private int _pendingCount;

    public SyncStatusViewModel(SyncEngine? engine)
    {
        _engine            = engine;
        IsServerConfigured = engine is not null;
        if (_engine is not null) _engine.StatusChanged += OnStatus;
    }

    private void OnStatus(SyncStatus s)
    {
        IsSyncing    = s.State == SyncState.Syncing;
        PendingCount = s.PendingEvents;
        StatusText   = s.State switch
        {
            SyncState.Idle    => PendingCount > 0 ? $"{PendingCount} ausstehend" : "Synchronisiert",
            SyncState.Syncing => "Synchronisiere…",
            SyncState.Offline => "Offline",
            SyncState.Error   => $"Fehler: {s.ErrorMessage}",
            _ => "",
        };
        LastSyncText = s.LastSyncAt.HasValue ? $"Zuletzt: {s.LastSyncAt:HH:mm}" : "Noch nie";
    }

    [RelayCommand(CanExecute = nameof(CanSync))]
    private async Task SyncNow() { if (_engine is not null) await _engine.SyncNowAsync(); }
    private bool CanSync() => _engine is not null && !IsSyncing;
}