/*
 * Copyright (c) 2025 Proton AG
 *
 * This file is part of ProtonVPN.
 *
 * ProtonVPN is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * ProtonVPN is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ProtonVPN.  If not, see <https://www.gnu.org/licenses/>.
 */

using CommunityToolkit.Mvvm.ComponentModel;
using ProtonVPN.Client.Common.Attributes;
using ProtonVPN.Client.Contracts.Services.Browsing;
using ProtonVPN.Client.Core.Bases;
using ProtonVPN.Client.Core.Services.Activation;
using ProtonVPN.Client.Core.Services.Navigation;
using ProtonVPN.Client.EventMessaging.Contracts;
using ProtonVPN.Client.Logic.Connection.Contracts;
using ProtonVPN.Client.Settings.Contracts;
using ProtonVPN.Client.Settings.Contracts.Messages;
using ProtonVPN.Client.Settings.Contracts.Observers;
using ProtonVPN.Client.Settings.Contracts.RequiredReconnections;
using ProtonVPN.Client.UI.Main.Settings.Bases;
using ProtonVPN.Common.Core.Extensions;
using ProtonVPN.Common.Core.Networking;

namespace ProtonVPN.Client.UI.Main.Settings.Pages.Connection;

public partial class ProtocolSettingsPageViewModel : SettingsPageViewModelBase,
    IEventMessageReceiver<FeatureFlagsChangedMessage>
{
    private readonly IUrlsBrowser _urlsBrowser;
    private readonly IFeatureFlagsObserver _featureFlagsObserver;

    [ObservableProperty]
    private bool _areProtonProtocolsEnabled;

    [ObservableProperty]
    [property: SettingName(nameof(ISettings.VpnProtocol))]
    [NotifyPropertyChangedFor(nameof(IsSmartProtocol))]
    [NotifyPropertyChangedFor(nameof(IsProTunUdpProtocol))]
    [NotifyPropertyChangedFor(nameof(IsProTunTcpProtocol))]
    [NotifyPropertyChangedFor(nameof(IsProTunTlsProtocol))]
    [NotifyPropertyChangedFor(nameof(IsWireGuardUdpProtocol))]
    [NotifyPropertyChangedFor(nameof(IsWireGuardTcpProtocol))]
    [NotifyPropertyChangedFor(nameof(IsWireGuardTlsProtocol))]
    [NotifyPropertyChangedFor(nameof(IsOpenVpnUdpProtocol))]
    [NotifyPropertyChangedFor(nameof(IsOpenVpnTcpProtocol))]
    private VpnProtocol _currentVpnProtocol;

    public bool IsProtonProtocolsFeatureEnabled => _featureFlagsObserver.IsProTunEnabled;

    public bool AreProtonProtocolsVisible => IsProtonProtocolsFeatureEnabled && AreProtonProtocolsEnabled;

    public override string Title => Localizer.Get("Settings_Connection_Protocol");

    public string Recommended => Localizer.Get("Common_Tags_Recommended").ToUpperInvariant();
    public string Beta => Localizer.Get("Common_Tags_Beta").ToUpperInvariant();

    public bool IsSmartProtocol
    {
        get => IsProtocol(VpnProtocol.Smart);
        set => SetProtocol(value, VpnProtocol.Smart);
    }

    public bool IsProTunUdpProtocol
    {
        get => IsProtocol(VpnProtocol.ProTunUdp);
        set => SetProtocol(value, VpnProtocol.ProTunUdp);
    }

    public bool IsProTunTcpProtocol
    {
        get => IsProtocol(VpnProtocol.ProTunTcp);
        set => SetProtocol(value, VpnProtocol.ProTunTcp);
    }

    public bool IsProTunTlsProtocol
    {
        get => IsProtocol(VpnProtocol.ProTunTls);
        set => SetProtocol(value, VpnProtocol.ProTunTls);
    }

    public bool IsWireGuardUdpProtocol
    {
        get => IsProtocol(VpnProtocol.WireGuardUdp);
        set => SetProtocol(value, VpnProtocol.WireGuardUdp);
    }

    public bool IsWireGuardTcpProtocol
    {
        get => IsProtocol(VpnProtocol.WireGuardTcp);
        set => SetProtocol(value, VpnProtocol.WireGuardTcp);
    }

    public bool IsWireGuardTlsProtocol
    {
        get => IsProtocol(VpnProtocol.WireGuardTls);
        set => SetProtocol(value, VpnProtocol.WireGuardTls);
    }

    public bool IsOpenVpnUdpProtocol
    {
        get => IsProtocol(VpnProtocol.OpenVpnUdp);
        set => SetProtocol(value, VpnProtocol.OpenVpnUdp);
    }

    public bool IsOpenVpnTcpProtocol
    {
        get => IsProtocol(VpnProtocol.OpenVpnTcp);
        set => SetProtocol(value, VpnProtocol.OpenVpnTcp);
    }

    public string LearnMoreUrl => _urlsBrowser.ProtocolsLearnMore;

    public ProtocolSettingsPageViewModel(
        IUrlsBrowser urlsBrowser,
        IRequiredReconnectionSettings requiredReconnectionSettings,
        IMainViewNavigator mainViewNavigator,
        ISettingsViewNavigator settingsViewNavigator,
        IMainWindowOverlayActivator mainWindowOverlayActivator,
        ISettings settings,
        ISettingsConflictResolver settingsConflictResolver,
        IConnectionManager connectionManager,
        IViewModelHelper viewModelHelper,
        IFeatureFlagsObserver featureFlagsObserver)
        : base(requiredReconnectionSettings,
               mainViewNavigator,
               settingsViewNavigator,
               mainWindowOverlayActivator,
               settings,
               settingsConflictResolver,
               connectionManager,
               viewModelHelper)
    {
        _urlsBrowser = urlsBrowser;
        _featureFlagsObserver = featureFlagsObserver;

        PageSettings =
        [
            ChangedSettingArgs.Create(() => Settings.AreProtonProtocolsEnabled, () => AreProtonProtocolsEnabled),
            ChangedSettingArgs.Create(() => Settings.VpnProtocol, () => CurrentVpnProtocol)
        ];
    }

    partial void OnAreProtonProtocolsEnabledChanged(bool value)
    {
        if (!value && CurrentVpnProtocol.IsProTun())
        {
            CurrentVpnProtocol = VpnProtocol.Smart;
        }
        OnPropertyChanged(nameof(AreProtonProtocolsVisible));
    }

    protected override void OnLanguageChanged()
    {
        base.OnLanguageChanged();

        OnPropertyChanged(nameof(Recommended));
        OnPropertyChanged(nameof(Beta));
    }

    protected override void OnRetrieveSettings()
    {
        AreProtonProtocolsEnabled = Settings.AreProtonProtocolsEnabled;

        VpnProtocol savedProtocol = Settings.VpnProtocol;
        CurrentVpnProtocol = AreProtonProtocolsVisible
            ? savedProtocol
            : savedProtocol.IsProTun()
                ? VpnProtocol.Smart
                : savedProtocol;
    }

    private bool IsProtocol(VpnProtocol protocol)
    {
        return CurrentVpnProtocol == protocol;
    }

    private void SetProtocol(bool value, VpnProtocol protocol)
    {
        if (value)
        {
            if (AreProtonProtocolsVisible || !protocol.IsProTun())
            {
                CurrentVpnProtocol = protocol;
            }
        }
    }

    public void Receive(FeatureFlagsChangedMessage message)
    {
        ExecuteOnUIThread(() =>
        {
            OnPropertyChanged(nameof(IsProtonProtocolsFeatureEnabled));
            OnPropertyChanged(nameof(AreProtonProtocolsVisible));
        });
    }
}