@page "/shared/{token}"
<PageTitle>@_playlist?.Title - Playlist Share</PageTitle>

@using PlaylistShared.Pwa.Components.Common
@using PlaylistShared.Pwa.Components.SharedPlaylist
@using PlaylistShared.Pwa.Components.SharedPlaylist.Cards
@using PlaylistShared.Shared.DTO
@using PlaylistShared.Shared.Enums
@using PlaylistShared.Pwa.Services
@using PlaylistShared.Shared.SharedPlaylist
@using PlaylistShared.Shared.Yandex
@inject HttpClient Http
@inject ISnackbar Snackbar
@inject NavigationManager Navigation
@inject AuthenticationStateProvider AuthProvider
@inject IDialogService DialogService

<MudContainer MaxWidth="MaxWidth.ExtraLarge" Class="pa-1" Style="height: 100%;">
    @if (_loading)
    {
        <MudProgressCircular Indeterminate />
    }
    else if (_playlist == null)
    {
        <MudAlert Severity="Severity.Error">Плейлист не найден или у вас нет доступа</MudAlert>
    }
    else
    {
        @* --- ВЕРСИЯ ДЛЯ ПК (сетка) --- *@
        <MudHidden Breakpoint="Breakpoint.MdAndUp" Invert>
            <MudGrid Spacing="2" Class="flex-grow-1 pt-2" Style="height: 100%;">
                <MudItem xs="12" md="6" Style="height: 100%;">
                    @PlaylistCardContent
                </MudItem>

                @if (_canAdd)
                {
                    <MudItem xs="12" md="6" Style="height: 100%;">
                        @AddTrackCardContent
                    </MudItem>
                }
            </MudGrid>
        </MudHidden>
        
        @* --- ВЕРСИЯ ДЛЯ МОБИЛОК (вкладки внизу) --- *@
        <MudHidden Breakpoint="Breakpoint.SmAndDown" Invert>
            <div class="d-flex flex-column pa-0 ma-0" style="height: 100%; min-height: 0;">
        
                @* Область контента: оба компонента здесь всегда *@
                <div class="flex-grow-1 relative pa-0" style="min-height: 0;">
                    <div class="@(_activeMobileTab == 0 ? "d-flex" : "d-none") flex-column" style="height: 100%;">
                        <div class="flex-grow-1 overflow-auto pb-1">
                            @PlaylistCardContent
                        </div>
                    </div>

                    <div class="@(_activeMobileTab == 1 ? "d-flex" : "d-none") flex-column" style="height: 100%;">
                        <div class="flex-grow-1 overflow-auto pb-1">
                            @AddTrackCardContent
                        </div>
                    </div>
                </div>

                @* Кастомная панель навигации внизу *@
                @if (_canAdd)
                {
                    <MudPaper Elevation="0" Class="py-1">
                        <MudNavMenu Margin="Margin.None" Class="d-flex flex-row justify-space-around">
                            <MudIconButton Icon="@Icons.Material.Filled.LibraryMusic"
                                           Color="@(_activeMobileTab == 0 ? Color.Primary : Color.Default)"
                                           OnClick="() => _activeMobileTab = 0" />
                                <MudIconButton Icon="@Icons.Material.Filled.AddCircle"
                                               Color="@(_activeMobileTab == 1 ? Color.Primary : Color.Default)"
                                               OnClick="() => _activeMobileTab = 1" />
                        </MudNavMenu>
                    </MudPaper>
                }
            </div>
        </MudHidden>
    }
</MudContainer>

<style>
    .horizontal-scroll-container {
        display: flex;
        overflow-x: auto;
        gap: 12px;
        padding-bottom: 8px;
        scroll-snap-type: x mandatory;
        -webkit-overflow-scrolling: touch;
    }
    .horizontal-scroll-container > div {
        scroll-snap-align: start;
        flex: 0 0 auto; /* Запрещает карточкам сжиматься */
    }
    /* Скрываем скроллбар для эстетики */
    .horizontal-scroll-container::-webkit-scrollbar { display: none; }
    .horizontal-scroll-container { -ms-overflow-style: none; scrollbar-width: none; }
</style>

@code {
    /// <summary>Токен расшаренного плейлиста</summary>
    [Parameter] public string Token { get; set; }

    private RenderFragment PlaylistCardContent => __builder =>
    {
        <MudCard Elevation="0" Class="d-flex flex-column" Style="height: 100%;">
            <MudCardHeader>
                <CardHeaderContent>
                    <PlaylistHeader Playlist="@_playlist" />
                </CardHeaderContent>
                <CardHeaderActions>
                    <MudIconButton Icon="@Icons.Material.Filled.Refresh" OnClick="LoadTracks" Disabled="@_tracksLoading" />
                </CardHeaderActions>
            </MudCardHeader>

            <MudCardContent Class="flex-grow-1 overflow-auto flex-column">
                <MudTable Items="@_tracks" Hover Elevation="0" Breakpoint="Breakpoint.None" Style="min-height: 0;">
                    <RowTemplate>
                        <MudTd Class="py-1 px-0" Style="width: 100%;">
                            <TrackItem Track="@context" PlaylistShareToken="@Token" CanPlay="@_canPlay" />
                        </MudTd>
                        @if (_canRemove)
                        {
                            <MudTd Class="py-1 px-0">
                                <MudIconButton Icon="@Icons.Material.Filled.Delete" Color="Color.Error" Size="Size.Small" OnClick="() => OnRemoveTrack(context)" />
                            </MudTd>
                        }
                    </RowTemplate>
                </MudTable>
            </MudCardContent>
        </MudCard>
    };

    private RenderFragment AddTrackCardContent => __builder =>
    {
        <MudCard Class="d-flex flex-column" Elevation="0" Style="height: 100%;">
            <MudCardHeader>
                <MudStack>
                    <MudText Typo="Typo.h6" Color="Color.Primary" Class="mb-4">Добавление треков</MudText>
                    <MudTextField @bind-Value="_searchQuery"
                                  @bind-Value:after="OnSearchQueryChanged"
                                  Variant="Variant.Outlined"
                                  FullWidth
                                  Label="Название или ссылка на трек"
                                  Disabled="@_isSearching"
                                  Adornment="Adornment.End" AdornmentIcon="@Icons.Material.Filled.Search" AdornmentColor="Color.Secondary" />

                    <MudToggleGroup T="TrackSearchType"
                                    @bind-Value="_searchType"
                                    @bind-Value:after="OnSearchTypeChanged"
                                    Size="Size.Small"
                                    Color="Color.Primary"
                                    Disabled="@(_isSearching)">
                        <MudToggleItem Value="TrackSearchType.All" Text="Все" />
                        <MudToggleItem Value="TrackSearchType.Track" Text="Треки" />
                        <MudToggleItem Value="TrackSearchType.Album" Text="Альбомы" />
                        <MudToggleItem Value="TrackSearchType.Playlist" Text="Плейлисты" />
                        <MudToggleItem Value="TrackSearchType.Artist" Text="Исполнители" />
                    </MudToggleGroup>
                </MudStack>
            </MudCardHeader>

            <MudCardContent Class="flex-grow-1 overflow-auto flex-column">
                @if (_isSearching)
                {
                    <MudProgressCircular Indeterminate Class="mx-auto my-8" />
                }
                else if (_searchResult != null)
                {
                    @* Секция исполнителей *@
                    @if (_searchResult?.Artists?.Any() == true)
                    {
                        <MudText Typo="Typo.h6" Class="mt-4 mb-2 ml-2">Исполнители</MudText>
                        <div class="horizontal-scroll-container px-2">
                            @foreach (var artist in _searchResult.Artists)
                            {
                                <div style="width: 70px;">
                                    <ArtistCard Item="artist" OnClick="() => SearchTracksByEntity(artist.Id, artist.Name, TrackSearchType.Artist)" />
                                </div>
                            }
                        </div>
                    }

                    @* Секция альбомов *@
                    @if (_searchResult?.Albums?.Any() == true)
                    {
                        <MudText Typo="Typo.h6" Class="mt-4 mb-2 ml-2">Альбомы</MudText>
                        <div class="horizontal-scroll-container px-2">
                            @foreach (var album in _searchResult.Albums)
                            {
                                <div style="width: 70px;">
                                    <AlbumCard Item="album" OnClick="() => SearchTracksByEntity(album.Id, album.Title, TrackSearchType.Album)" />
                                </div>
                            }
                        </div>
                    }

                    @* Секция плейлистов *@
                    @if (_searchResult?.Playlists?.Any() == true)
                    {
                        <MudText Typo="Typo.h6" Class="mt-4 mb-2 ml-2">Плейлисты</MudText>
                        <div class="horizontal-scroll-container px-2">
                            @foreach (var playlist in _searchResult.Playlists)
                            {
                                <div style="width: 70px;">
                                    <PlaylistCard Item="playlist" OnClick="() => SearchTracksByEntity(playlist.Uuid, playlist.Title, TrackSearchType.Playlist)" />
                                </div>
                            }
                        </div>
                    }

                    @* Секция треков *@
                    @if (_searchResult?.Tracks != null)
                    {
                        <MudText Typo="Typo.h6" Class="mt-4 mb-2 ml-2">Треки</MudText>
                        <MudTable Items="@_searchResult.Tracks"
                                    Hover
                                    Elevation="0"
                                    Style="min-height: 0; height: 100%;"
                                    Breakpoint="Breakpoint.None">
                            <RowTemplate>
                                <MudTd Class="py-1 px-0" Style="width: 100%;">
                                    <TrackItem Track="@context" PlaylistShareToken="@Token" CanPlay="@_canPlay" />
                                </MudTd>
                                @if (_canAdd)
                                {
                         
                                    <MudTd Class="py-1 px-0">
                                        <MudToggleIconButton Toggled="@_existingTrackIds.Contains(context.TrackId)"
                                                                Icon="@Icons.Material.Filled.AddCircle"
                                                                Color="@Color.Primary"
                                                                ToggledIcon="@Icons.Material.Filled.RemoveCircle"
                                                                ToggledColor="@Color.Error"
                                                                ToggledChanged="() => ToggleTrack(context)" />
                                    </MudTd>   
                                }
                            </RowTemplate>
                        </MudTable>
                    }
                }
            </MudCardContent>
        </MudCard>
    };

    /// <summary>Активная вкладка для моб.версии (0 = плейлист, 1 = добавление треков)</summary>
    private int _activeMobileTab = 0;

    /// <summary>
    /// Список ID треков, уже добавленных в плейлист. 
    /// Используется для быстрого определения, добавлен трек или нет, при отображении результатов поиска.
    /// </summary>
    private HashSet<string> _existingTrackIds = new();
    /// <summary>
    /// Список добавленных в плейлист треков.
    /// </summary>
    private List<YandexTrack> _tracks = new();

    /// <summary>Свойства плейлиста.</summary>
    private SharedPlaylistDto? _playlist;
    /// <summary>Пользователь является создателем плейлиста.</summary>
    private bool _isCreator;
    /// <summary>Пользователь имеет право воспроизведения треков.</summary>
    private bool _canPlay;
    /// <summary>Пользователь имеет право добавления треков в плейлист.</summary>
    private bool _canAdd;
    /// <summary>Пользователь имеет право удаления треков из плейлиста.</summary>
    private bool _canRemove;
    /// <summary>Пользователь авторизован из под учетной записи.</summary>
    private bool _isAuthenticated;
    /// <summary>Текущий ID пользователя, если авторизован.</summary>
    private string? _currentUserId;

    /// <summary>Состояние: Происходит загрузка плейлиста.</summary>
    private bool _loading = true;
    /// <summary>Состояние: Происходит загрузка треков плейлиста.</summary>
    private bool _tracksLoading;

    /********************************
     * Вкладка добавления треков
    *********************************/
    /// <summary>Строка запроса поиска.</summary>
    private string _searchQuery = "";
    /// <summary>Тип поиска.</summary>
    private TrackSearchType _searchType = TrackSearchType.All;
    /// <summary>Состояние: Происходит поиск.</summary>
    private bool _isSearching = false;
    
    /// <summary>Результат поиска.</summary>
    private YandexSearchResult? _searchResult = null;

    protected override async Task OnInitializedAsync()
    {
        var authState = await AuthProvider.GetAuthenticationStateAsync();
        _isAuthenticated = authState.User.Identity?.IsAuthenticated == true;
        _currentUserId = authState.User.FindFirst(System.Security.Claims.ClaimTypes.NameIdentifier)?.Value;
        await LoadPlaylist();
        await LoadTracks();
    }

    /// <summary>Установка разрешений.</summary>
    private async Task ConfigurePermissions()
    {
        if (_playlist is null)
        {
            _isCreator = false;
            _canAdd = false;
            _canRemove = false;
            _canPlay = false;
        }
        else
        {
            _isCreator = _playlist.CreatorUserId.ToString() == _currentUserId;

            _canAdd = _isCreator
            || _playlist.AddPermission == EditPermission.Everyone
            || (_playlist.AddPermission == EditPermission.AuthorizedOnly && _isAuthenticated);

            _canRemove = _isCreator
            || _playlist.RemovePermission == EditPermission.Everyone
            || (_playlist.RemovePermission == EditPermission.AuthorizedOnly && _isAuthenticated);

            _canPlay = _isCreator
            || _playlist.PlayPermission == ViewPermission.Everyone
            || (_playlist.PlayPermission == ViewPermission.AuthorizedOnly && _isAuthenticated);

        }
    }
    
    /// <summary>Загрузка плейлиста.</summary>
    private async Task LoadPlaylist()
    {
        try
        {
            var response = await Http.GetFromJsonAsync<ApiResponse<SharedPlaylistDto>>($"/api/sharedplaylist/{Token}");
            if (response?.Success == true)
            {
                _playlist = response.Data;
                _activeMobileTab = 0;

                await ConfigurePermissions();
            }
            else
            {
                Snackbar.Add(response?.Error?.Message ?? "Не удалось загрузить плейлист", Severity.Error);
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"Ошибка: {ex.Message}", Severity.Error);
        }
        finally
        {
            _loading = false;
            StateHasChanged();
        }
    }
    
    /// <summary>Загрузка треков.</summary>
    private async Task LoadTracks()
    {
        if (_playlist == null) return;

        _tracksLoading = true;

        try
        {
            var response = await Http.GetFromJsonAsync<ApiResponse<YandexPlaylistData>>($"/api/sharedplaylist/{Token}/tracks");
            if (response?.Success == true && response.Data != null)
            {
                _tracks = response.Data.Tracks;
                await GenerateUniqTrackIds();
            }
            else
            {
                Snackbar.Add(response?.Error?.Message ?? "Не удалось загрузить треки", Severity.Error);
            }

        }
        catch (Exception ex)
        {
            Snackbar.Add($"Ошибка загрузки треков: {ex.Message}", Severity.Error);
        }
        finally
        {
            _tracksLoading = false;
            StateHasChanged();
        }
    }

    private async Task GenerateUniqTrackIds()
    {
        _existingTrackIds = _tracks.Select(t => t.TrackId).ToHashSet();
    }

    /// <summary>Удаление трека из списка плейлиста</summary>
    private async Task OnRemoveTrack(YandexTrack track)
    {
        var confirmed = await DialogService.ShowMessageBoxAsync(
            "Подтверждение удаления",
            $"Вы уверены, что хотите удалить трек \"{track.Title}\"?",
            yesText: "Удалить", cancelText: "Отмена");

        if (confirmed != true) return;

        await RemoveTrack(track);
    }


    
    #region Добавление/удаление трека
    /// <summary>Добавление трека.</summary>
    private async Task AddTrack(YandexTrack track)
    {
        if (_existingTrackIds.Contains(track.TrackId)) return;

        try
        {
            var request = new UpdateTrackListRequest { TrackIds = new List<string> { track.TrackId } };
            var response = await Http.PostAsJsonAsync($"/api/sharedplaylist/{Token}/add-tracks", request);
            if (response.IsSuccessStatusCode)
            {
                Snackbar.Add($"Трек \"{track.Title}\" добавлен", Severity.Success, c => c.SnackbarVariant = Variant.Outlined);
                _tracks.Add(track);
                await GenerateUniqTrackIds();
            }
            else
            {
                var error = await response.Content.ReadFromJsonAsync<ApiResponse<object>>();
                Snackbar.Add(error?.Error?.Message ?? "Ошибка добавления трека", Severity.Error);
            }
            
        }
        catch (Exception ex)
        {
            Snackbar.Add($"Ошибка: {ex.Message}", Severity.Error);
        }
        StateHasChanged();
    }

    /// <summary>Удаление трека.</summary>
    private async Task RemoveTrack(YandexTrack track)
    {
        if (!_existingTrackIds.Contains(track.TrackId)) return;

        try
        {
            var request = new UpdateTrackListRequest { TrackIds = new List<string> { track.TrackId } };
            var response = await Http.PostAsJsonAsync($"/api/sharedplaylist/{Token}/remove-tracks", request);
            if (response.IsSuccessStatusCode)
            {
                Snackbar.Add("Трек удалён", Severity.Success);
                _tracks.Remove(track);
                await GenerateUniqTrackIds();
            }
            else
            {
                var error = await response.Content.ReadFromJsonAsync<ApiResponse<object>>();
                Snackbar.Add(error?.Error?.Message ?? "Ошибка удаления", Severity.Error);
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"Ошибка: {ex.Message}", Severity.Error);
        }
        StateHasChanged();
    }
    #endregion

    #region Вкладка Добавление треков
    private async Task OnSearchQueryChanged()
    {
        await SearchTracks(byId: false);
    }

    private async Task OnSearchTypeChanged()
    {
        await SearchTracks(byId: false);
    }

    /// <summary>
    /// Поиск трека
    /// </summary>
    /// <param name="byId">По ID</param>
    /// <param name="forcedQuery">Принудительный запрос</param>
    /// <returns></returns>
    private async Task SearchTracks(bool byId = false, string? forcedQuery = null)
    {
        var query = forcedQuery ?? _searchQuery;
        if (string.IsNullOrWhiteSpace(query))
        {
            _searchResult = null;
            return;
        }

        var type = _searchType;

        // Распознавание ссылки Яндекс.Музыки
        if (!byId && Uri.TryCreate(query, UriKind.Absolute, out var uri) && uri.Host == "music.yandex.ru")
        {
            try
            {
                (type, query) = ParseYandexMusicUrl(uri);
                byId = true;
            }
            catch (Exception ex)
            {
                Snackbar.Add($"Ошибка распознавания URL: {ex.Message}", Severity.Error);
                return;
            }
        }

        _isSearching = true;
        _searchResult = null;
        StateHasChanged();

        try
        {
            var url = $"/api/yandexsearch/search?query={Uri.EscapeDataString(query)}&searchType={Uri.EscapeDataString(type.ToString())}&limit=20";
            if (byId)
                url += "&byId=true";
            if (!string.IsNullOrEmpty(Token))
                url += $"&shared_id={Uri.EscapeDataString(Token)}";

            var response = await Http.GetFromJsonAsync<ApiResponse<YandexSearchResult>>(url);
            if (response?.Success == true)
            {
                _searchResult = response.Data ?? new YandexSearchResult();
            }
            else
            {
                Snackbar.Add(response?.Error?.Message ?? "Ошибка поиска", Severity.Error);
                _searchResult = null;
            }
        }
        catch (Exception ex)
        {
            Snackbar.Add($"Ошибка: {ex.Message}", Severity.Error);
            _searchResult = null;
        }
        finally
        {
            _isSearching = false;
            StateHasChanged();
        }
    }
    
    /// <summary>Поиск по определенному типу результата.</summary>
    private async Task SearchTracksByEntity(string entityId, string title, TrackSearchType entityType)
    {
        // Переключаем тип и ищем по ID
        _searchType = entityType;
        _searchQuery = title;
        await SearchTracks(byId: true, forcedQuery: entityId);
    }
    
    /// <summary>Переключатель "Добавление/Удаление" трека</summary>
    private async Task ToggleTrack(YandexTrack track)
    {
        if (_existingTrackIds.Contains(track.TrackId))
            await RemoveTrack(track);
        else
            await AddTrack(track);
    }
    
    /// <summary>Парсинг ссылки на яндекс трек</summary>
    private static (TrackSearchType Type, string Id) ParseYandexMusicUrl(Uri uri)
    {
        var segments = uri.AbsolutePath.Split('/', StringSplitOptions.RemoveEmptyEntries);
        
        var dataMap = segments
            .Select((val, idx) => new { val, idx })
            .GroupBy(x => x.idx / 2)
            .ToDictionary(
                g => g.First().val,
                g => g.ElementAtOrDefault(1)?.val
            );

        if (dataMap.TryGetValue("track", out var trackId) && !string.IsNullOrEmpty(trackId))
            return (TrackSearchType.Track, trackId);
        if (dataMap.TryGetValue("album", out var albumId) && !string.IsNullOrEmpty(albumId))
            return (TrackSearchType.Album, albumId);
        if (dataMap.TryGetValue("playlist", out var playlistId) && !string.IsNullOrEmpty(playlistId))
            return (TrackSearchType.Playlist, playlistId);
        if (dataMap.TryGetValue("artist", out var artistId) && !string.IsNullOrEmpty(artistId))
            return (TrackSearchType.Artist, artistId);

        throw new ArgumentException("Unsupported URL pattern");
    }
    #endregion
}