using System.Collections.ObjectModel;
using System.IO;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.Extensions.Logging;
using Microsoft.Win32;
using SharepointToolbox.Core.Models;
using SharepointToolbox.Services;
using AppGraphClientFactory = SharepointToolbox.Infrastructure.Auth.GraphClientFactory;

namespace SharepointToolbox.ViewModels;

public partial class ProfileManagementViewModel : ObservableObject
{
    private readonly ProfileService _profileService;
    private readonly IBrandingService _brandingService;
    private readonly AppGraphClientFactory _graphClientFactory;
    private readonly ILogger<ProfileManagementViewModel> _logger;

    [ObservableProperty]
    private TenantProfile? _selectedProfile;

    [ObservableProperty]
    private string _newName = string.Empty;

    [ObservableProperty]
    private string _newTenantUrl = string.Empty;

    [ObservableProperty]
    private string _newClientId = string.Empty;

    [ObservableProperty]
    private string _validationMessage = string.Empty;

    private string? _clientLogoPreview;
    public string? ClientLogoPreview
    {
        get => _clientLogoPreview;
        private set { _clientLogoPreview = value; OnPropertyChanged(); }
    }

    public ObservableCollection<TenantProfile> Profiles { get; } = new();

    public IAsyncRelayCommand AddCommand { get; }
    public IAsyncRelayCommand RenameCommand { get; }
    public IAsyncRelayCommand DeleteCommand { get; }
    public IAsyncRelayCommand BrowseClientLogoCommand { get; }
    public IAsyncRelayCommand ClearClientLogoCommand { get; }
    public IAsyncRelayCommand AutoPullClientLogoCommand { get; }

    public ProfileManagementViewModel(
        ProfileService profileService,
        IBrandingService brandingService,
        AppGraphClientFactory graphClientFactory,
        ILogger<ProfileManagementViewModel> logger)
    {
        _profileService = profileService;
        _brandingService = brandingService;
        _graphClientFactory = graphClientFactory;
        _logger = logger;

        AddCommand = new AsyncRelayCommand(AddAsync, CanAdd);
        RenameCommand = new AsyncRelayCommand(RenameAsync, () => SelectedProfile != null && !string.IsNullOrWhiteSpace(NewName));
        DeleteCommand = new AsyncRelayCommand(DeleteAsync, () => SelectedProfile != null);
        BrowseClientLogoCommand = new AsyncRelayCommand(BrowseClientLogoAsync, () => SelectedProfile != null);
        ClearClientLogoCommand = new AsyncRelayCommand(ClearClientLogoAsync, () => SelectedProfile != null);
        AutoPullClientLogoCommand = new AsyncRelayCommand(AutoPullClientLogoAsync, () => SelectedProfile != null);
    }

    public async Task LoadAsync()
    {
        try
        {
            var profiles = await _profileService.GetProfilesAsync();
            Profiles.Clear();
            foreach (var p in profiles)
                Profiles.Add(p);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Failed to load profiles.");
        }
    }

    partial void OnNewNameChanged(string value) => NotifyCommandsCanExecuteChanged();
    partial void OnNewTenantUrlChanged(string value) => NotifyCommandsCanExecuteChanged();
    partial void OnNewClientIdChanged(string value) => NotifyCommandsCanExecuteChanged();

    partial void OnSelectedProfileChanged(TenantProfile? value)
    {
        ClientLogoPreview = FormatLogoPreview(value?.ClientLogo);
        BrowseClientLogoCommand.NotifyCanExecuteChanged();
        ClearClientLogoCommand.NotifyCanExecuteChanged();
        AutoPullClientLogoCommand.NotifyCanExecuteChanged();
        RenameCommand.NotifyCanExecuteChanged();
        DeleteCommand.NotifyCanExecuteChanged();
    }

    private static string? FormatLogoPreview(LogoData? logo)
        => logo is not null ? $"data:{logo.MimeType};base64,{logo.Base64}" : null;

    private void NotifyCommandsCanExecuteChanged()
    {
        AddCommand.NotifyCanExecuteChanged();
        RenameCommand.NotifyCanExecuteChanged();
    }

    private bool CanAdd()
    {
        if (string.IsNullOrWhiteSpace(NewName)) return false;
        if (!Uri.TryCreate(NewTenantUrl, UriKind.Absolute, out _)) return false;
        if (string.IsNullOrWhiteSpace(NewClientId)) return false;
        return true;
    }

    private async Task AddAsync()
    {
        if (!CanAdd()) return;
        try
        {
            var profile = new TenantProfile
            {
                Name = NewName.Trim(),
                TenantUrl = NewTenantUrl.Trim(),
                ClientId = NewClientId.Trim()
            };
            await _profileService.AddProfileAsync(profile);
            Profiles.Add(profile);
            NewName = string.Empty;
            NewTenantUrl = string.Empty;
            NewClientId = string.Empty;
            ValidationMessage = string.Empty;
        }
        catch (Exception ex)
        {
            ValidationMessage = ex.Message;
            _logger.LogError(ex, "Failed to add profile.");
        }
    }

    private async Task RenameAsync()
    {
        if (SelectedProfile == null || string.IsNullOrWhiteSpace(NewName)) return;
        try
        {
            await _profileService.RenameProfileAsync(SelectedProfile.Name, NewName.Trim());
            SelectedProfile.Name = NewName.Trim();
            NewName = string.Empty;
        }
        catch (Exception ex)
        {
            ValidationMessage = ex.Message;
            _logger.LogError(ex, "Failed to rename profile.");
        }
    }

    private async Task DeleteAsync()
    {
        if (SelectedProfile == null) return;
        try
        {
            await _profileService.DeleteProfileAsync(SelectedProfile.Name);
            Profiles.Remove(SelectedProfile);
            SelectedProfile = null;
        }
        catch (Exception ex)
        {
            ValidationMessage = ex.Message;
            _logger.LogError(ex, "Failed to delete profile.");
        }
    }

    private async Task BrowseClientLogoAsync()
    {
        if (SelectedProfile == null) return;
        var dialog = new OpenFileDialog
        {
            Title = "Select client logo",
            Filter = "Image files (*.png;*.jpg;*.jpeg)|*.png;*.jpg;*.jpeg",
        };
        if (dialog.ShowDialog() != true) return;
        try
        {
            var logo = await _brandingService.ImportLogoAsync(dialog.FileName);
            SelectedProfile.ClientLogo = logo;
            ClientLogoPreview = FormatLogoPreview(logo);
            await _profileService.UpdateProfileAsync(SelectedProfile);
            ValidationMessage = string.Empty;
        }
        catch (Exception ex)
        {
            ValidationMessage = ex.Message;
            _logger.LogError(ex, "Failed to import client logo.");
        }
    }

    private async Task ClearClientLogoAsync()
    {
        if (SelectedProfile == null) return;
        try
        {
            SelectedProfile.ClientLogo = null;
            ClientLogoPreview = null;
            await _profileService.UpdateProfileAsync(SelectedProfile);
            ValidationMessage = string.Empty;
        }
        catch (Exception ex)
        {
            ValidationMessage = ex.Message;
            _logger.LogError(ex, "Failed to clear client logo.");
        }
    }

    private async Task AutoPullClientLogoAsync()
    {
        if (SelectedProfile == null) return;
        try
        {
            var graphClient = await _graphClientFactory.CreateClientAsync(
                SelectedProfile.ClientId, CancellationToken.None);

            var orgs = await graphClient.Organization.GetAsync();
            var orgId = orgs?.Value?.FirstOrDefault()?.Id;
            if (orgId is null)
            {
                ValidationMessage = "Could not determine organization ID.";
                return;
            }

            var stream = await graphClient.Organization[orgId]
                .Branding.Localizations["default"].SquareLogo.GetAsync();

            if (stream is null || stream.Length == 0)
            {
                ValidationMessage = "No branding logo found for this tenant.";
                return;
            }

            using var ms = new MemoryStream();
            await stream.CopyToAsync(ms);
            var bytes = ms.ToArray();

            var logo = await _brandingService.ImportLogoFromBytesAsync(bytes);
            SelectedProfile.ClientLogo = logo;
            ClientLogoPreview = FormatLogoPreview(logo);
            await _profileService.UpdateProfileAsync(SelectedProfile);
            ValidationMessage = "Client logo pulled from Entra branding.";
        }
        catch (Microsoft.Graph.Models.ODataErrors.ODataError ex) when (ex.ResponseStatusCode == 404)
        {
            ValidationMessage = "No Entra branding configured for this tenant.";
        }
        catch (Exception ex)
        {
            ValidationMessage = $"Failed to pull logo: {ex.Message}";
            _logger.LogWarning(ex, "Auto-pull client logo failed.");
        }
    }
}