@page "/group/{GroupId:guid}"
@using GmRelay.Web.Services
@using GmRelay.Shared.Domain
@using Microsoft.AspNetCore.Authorization
@using Microsoft.AspNetCore.Components.Authorization
@attribute [Authorize]
@inject AuthorizedSessionService SessionService
@inject AuthenticationStateProvider AuthStateProvider
@inject NavigationManager Navigation

<PageTitle>Сессии группы — GM-Relay</PageTitle>

<div class="page-container">
    <ul class="gm-breadcrumb animate-fade-in">
        <li><a href="/">Главная</a></li>
        <li class="active">Сессии группы</li>
    </ul>

    <div class="page-header animate-fade-in">
        <h2>📅 Предстоящие игры</h2>
    </div>

    @if (!string.IsNullOrEmpty(errorMessage))
    {
        <div class="gm-alert gm-alert-danger" style="margin-bottom: 1rem;">
            ⚠️ @errorMessage
        </div>
    }

    @if (!string.IsNullOrEmpty(successMessage))
    {
        <div class="gm-alert gm-alert-success" style="margin-bottom: 1rem;">
            ✅ @successMessage
        </div>
    }

    @if (sessions == null)
    {
        <div class="glass-card" style="padding: 2rem;">
            <div class="skeleton skeleton-text" style="width: 80%; margin-bottom: 1rem;"></div>
            <div class="skeleton skeleton-text" style="width: 60%; margin-bottom: 0.75rem;"></div>
            <div class="skeleton skeleton-text" style="width: 70%; margin-bottom: 0.75rem;"></div>
            <div class="skeleton skeleton-text" style="width: 50%;"></div>
        </div>
    }
    else if (sessions.Count == 0)
    {
        <div class="glass-card">
            <div class="empty-state">
                <div class="empty-state-icon">🎯</div>
                <div class="empty-state-title">Нет предстоящих сессий</div>
                <p class="empty-state-text">Для этой группы пока не запланировано игровых сессий.</p>
            </div>
        </div>
    }
    else
    {
        <div class="batch-bulk-grid animate-slide-up">
            @foreach (var batch in batchModels)
            {
                <div class="batch-bulk-card">
                    <div class="batch-bulk-header">
                        <div>
                            <h3>@batch.Title</h3>
                            <p>@FormatBatchSummary(batch)</p>
                        </div>
                        <span class="status-badge status-info">Batch</span>
                    </div>

                    <EditForm Model="@batch" OnValidSubmit="@(() => UpdateBatchDetails(batch))">
                        <div class="batch-bulk-fields">
                            <div class="gm-form-group">
                                <label class="gm-form-label">Общее название</label>
                                <InputText @bind-Value="batch.Title" class="gm-form-control" />
                            </div>
                            <div class="gm-form-group">
                                <label class="gm-form-label">Общая ссылка</label>
                                <InputText @bind-Value="batch.JoinLink" class="gm-form-control" />
                            </div>
                            <div class="gm-form-group">
                                <label class="gm-form-label">Уведомления игрокам</label>
                                <select @bind="batch.NotificationMode" class="gm-form-control">
                                    <option value="@SessionNotificationModeExtensions.GroupAndDirectValue">В группе и в личку</option>
                                    <option value="@SessionNotificationModeExtensions.GroupOnlyValue">Только в группе</option>
                                </select>
                            </div>
                        </div>
                        <button type="submit" class="btn-gm btn-gm-primary" disabled="@IsBatchBusy(batch)">
                            @(IsBatchBusy(batch) ? "⏳ Обновляем..." : "💾 Обновить batch")
                        </button>
                    </EditForm>

                    <div class="batch-bulk-divider"></div>

                    <EditForm Model="@batch" OnValidSubmit="@(() => RescheduleBatch(batch))">
                        <div class="batch-bulk-fields">
                            <div class="gm-form-group">
                                <label class="gm-form-label">Первая дата пачки (МСК, UTC+3)</label>
                                <input type="datetime-local" @bind="batch.FirstScheduledAtLocal" class="gm-form-control" />
                            </div>
                            <div class="gm-form-group">
                                <label class="gm-form-label">Шаг между играми, дней</label>
                                <InputNumber @bind-Value="batch.IntervalDays" class="gm-form-control" min="1" />
                            </div>
                        </div>
                        <button type="submit" class="btn-gm btn-gm-outline" disabled="@IsBatchBusy(batch)">
                            @(IsBatchBusy(batch) ? "⏳ Переносим..." : "📅 Перенести пачку")
                        </button>
                    </EditForm>

                    <div class="batch-clone-row">
                        <select @bind="batch.CloneInterval" class="gm-form-control">
                            <option value="week">Следующая неделя</option>
                            <option value="month">Следующий месяц</option>
                        </select>
                        <button type="button" class="btn-gm btn-gm-success" disabled="@IsBatchBusy(batch)" @onclick="() => CloneBatch(batch)">
                            @(IsBatchBusy(batch) ? "⏳ Клонируем..." : "🧬 Клонировать")
                        </button>
                    </div>
                </div>
            }
        </div>

        @* Desktop table *@
        <div class="glass-card session-table-desktop animate-slide-up" style="padding: 0; overflow: hidden;">
            <table class="gm-table">
                <thead>
                    <tr>
                        <th>Название</th>
                        <th>Время (МСК)</th>
                        <th>Места</th>
                        <th>Статус</th>
                        <th>Ссылка</th>
                        <th>Действие</th>
                    </tr>
                </thead>
                <tbody>
                    @foreach (var session in sessions)
                    {
                        <tr>
                            <td style="color: var(--text-primary); font-weight: 500;">@session.Title</td>
                            <td>@session.ScheduledAt.FormatMoscow()</td>
                            <td>@FormatSeats(session)</td>
                            <td>
                                <span class="status-badge @GetStatusClass(session.Status)">@TranslateStatus(session.Status)</span>
                            </td>
                            <td>
                                <a href="@session.JoinLink" target="_blank" rel="noopener noreferrer"
                                   style="max-width: 150px; display: inline-block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;">
                                    Подключиться ↗
                                </a>
                            </td>
                            <td>
                                <div style="display: flex; gap: 0.5rem; flex-wrap: wrap;">
                                    <a href="/session/edit/@session.Id" class="btn-gm btn-gm-outline" style="font-size: 0.8125rem; padding: 0.375rem 0.75rem;">
                                        ✏️ Изменить
                                    </a>
                                    @if (CanPromote(session))
                                    {
                                        <button type="button" class="btn-gm btn-gm-success" style="font-size: 0.8125rem; padding: 0.375rem 0.75rem;" disabled="@(promotingSessionId == session.Id)" @onclick="() => PromoteWaitlisted(session.Id)">
                                            @(promotingSessionId == session.Id ? "⏳ Поднимаем..." : "⬆️ Из ожидания")
                                        </button>
                                    }
                                </div>
                            </td>
                        </tr>
                    }
                </tbody>
            </table>
        </div>

        @* Mobile cards *@
        <div class="session-card-mobile stagger-children">
            @foreach (var session in sessions)
            {
                <div class="session-card">
                    <div class="session-card-header">
                        <span class="session-card-title">@session.Title</span>
                        <span class="status-badge @GetStatusClass(session.Status)">@TranslateStatus(session.Status)</span>
                    </div>
                    <div class="session-card-body">
                        <div class="session-card-row">
                            <span>🕐 Время</span>
                            <span style="color: var(--text-primary);">@session.ScheduledAt.FormatMoscow()</span>
                        </div>
                        <div class="session-card-row">
                            <span>👥 Места</span>
                            <span style="color: var(--text-primary);">@FormatSeats(session)</span>
                        </div>
                        <div class="session-card-row">
                            <span>🔗 Ссылка</span>
                            <a href="@session.JoinLink" target="_blank" rel="noopener noreferrer">Подключиться ↗</a>
                        </div>
                    </div>
                    <div class="session-card-actions">
                        <a href="/session/edit/@session.Id" class="btn-gm btn-gm-outline" style="flex: 1; justify-content: center; font-size: 0.8125rem; padding: 0.5rem;">
                            ✏️ Изменить
                        </a>
                        @if (CanPromote(session))
                        {
                            <button type="button" class="btn-gm btn-gm-success" style="flex: 1; justify-content: center; font-size: 0.8125rem; padding: 0.5rem;" disabled="@(promotingSessionId == session.Id)" @onclick="() => PromoteWaitlisted(session.Id)">
                                @(promotingSessionId == session.Id ? "⏳ Поднимаем..." : "⬆️ Из ожидания")
                            </button>
                        }
                    </div>
                </div>
            }
        </div>
    }
</div>

@code {
    [Parameter] public Guid GroupId { get; set; }
    private List<WebSession>? sessions;
    private List<BatchBulkEditModel> batchModels = [];
    private Guid? promotingSessionId;
    private Guid? processingBatchId;
    private long telegramId;
    private string? errorMessage;
    private string? successMessage;

    protected override async Task OnInitializedAsync()
    {
        var authState = await AuthStateProvider.GetAuthenticationStateAsync();
        if (!authState.User.TryGetTelegramId(out telegramId))
        {
            Navigation.NavigateTo("/access-denied");
            return;
        }

        await LoadSessions();
    }

    private async Task LoadSessions()
    {
        sessions = await SessionService.GetUpcomingSessionsForGmAsync(GroupId, telegramId);
        if (sessions is null)
        {
            Navigation.NavigateTo("/access-denied");
            return;
        }

        RebuildBatchModels();
    }

    private async Task PromoteWaitlisted(Guid sessionId)
    {
        errorMessage = null;
        successMessage = null;
        promotingSessionId = sessionId;

        try
        {
            await SessionService.PromoteWaitlistedPlayerForGmAsync(sessionId, telegramId);
            await LoadSessions();
        }
        catch (SessionAccessDeniedException)
        {
            Navigation.NavigateTo("/access-denied");
        }
        catch (Exception ex)
        {
            errorMessage = ex.Message;
        }
        finally
        {
            promotingSessionId = null;
        }
    }

    private async Task UpdateBatchDetails(BatchBulkEditModel batch)
    {
        errorMessage = null;
        successMessage = null;

        if (!ValidateBatchDetails(batch))
        {
            errorMessage = "Название и ссылка для batch не должны быть пустыми.";
            return;
        }

        processingBatchId = batch.BatchId;

        try
        {
            await SessionService.UpdateBatchDetailsForGmAsync(batch.BatchId, telegramId, batch.Title, batch.JoinLink);
            await SessionService.UpdateBatchNotificationModeForGmAsync(
                batch.BatchId,
                telegramId,
                SessionNotificationModeExtensions.FromDatabaseValue(batch.NotificationMode));
            successMessage = "Настройки batch обновлены.";
            await LoadSessions();
        }
        catch (SessionAccessDeniedException)
        {
            Navigation.NavigateTo("/access-denied");
        }
        catch (Exception ex)
        {
            errorMessage = "Не удалось обновить пачку: " + ex.Message;
        }
        finally
        {
            processingBatchId = null;
        }
    }

    private async Task RescheduleBatch(BatchBulkEditModel batch)
    {
        errorMessage = null;
        successMessage = null;

        if (batch.IntervalDays <= 0)
        {
            errorMessage = "Шаг между играми должен быть больше 0 дней.";
            return;
        }

        processingBatchId = batch.BatchId;

        try
        {
            var utcTime = new DateTimeOffset(batch.FirstScheduledAtLocal, TimeSpan.FromHours(3)).ToUniversalTime().UtcDateTime;
            await SessionService.RescheduleBatchForGmAsync(batch.BatchId, telegramId, utcTime, batch.IntervalDays);
            successMessage = "Расписание пачки обновлено.";
            await LoadSessions();
        }
        catch (SessionAccessDeniedException)
        {
            Navigation.NavigateTo("/access-denied");
        }
        catch (Exception ex)
        {
            errorMessage = "Не удалось перенести пачку: " + ex.Message;
        }
        finally
        {
            processingBatchId = null;
        }
    }

    private async Task CloneBatch(BatchBulkEditModel batch)
    {
        errorMessage = null;
        successMessage = null;
        processingBatchId = batch.BatchId;

        try
        {
            var interval = batch.CloneInterval == "month"
                ? BatchCloneInterval.NextMonth
                : BatchCloneInterval.NextWeek;

            var clonedBatch = await SessionService.CloneBatchForGmAsync(batch.BatchId, telegramId, interval);
            successMessage = $"Пачка склонирована: {clonedBatch.SessionCount} игр.";
            await LoadSessions();
        }
        catch (SessionAccessDeniedException)
        {
            Navigation.NavigateTo("/access-denied");
        }
        catch (Exception ex)
        {
            errorMessage = "Не удалось клонировать пачку: " + ex.Message;
        }
        finally
        {
            processingBatchId = null;
        }
    }

    private void RebuildBatchModels()
    {
        batchModels = sessions?
            .GroupBy(session => session.BatchId)
            .Select(group =>
            {
                var orderedSessions = group.OrderBy(session => session.ScheduledAt).ToList();
                var firstSession = orderedSessions[0];
                var lastSession = orderedSessions[^1];

                return new BatchBulkEditModel
                {
                    BatchId = group.Key,
                    Title = firstSession.Title,
                    JoinLink = firstSession.JoinLink,
                    NotificationMode = firstSession.NotificationMode,
                    FirstScheduledAtLocal = firstSession.ScheduledAt.ToMoscow(),
                    LastScheduledAtLocal = lastSession.ScheduledAt.ToMoscow(),
                    IntervalDays = InferIntervalDays(orderedSessions),
                    SessionCount = orderedSessions.Count
                };
            })
            .OrderBy(batch => batch.FirstScheduledAtLocal)
            .ToList() ?? [];
    }

    private static bool ValidateBatchDetails(BatchBulkEditModel batch)
    {
        batch.Title = batch.Title.Trim();
        batch.JoinLink = batch.JoinLink.Trim();
        return batch.Title.Length > 0 && batch.JoinLink.Length > 0;
    }

    private bool IsBatchBusy(BatchBulkEditModel batch) => processingBatchId == batch.BatchId;

    private static int InferIntervalDays(IReadOnlyList<WebSession> orderedSessions)
    {
        if (orderedSessions.Count < 2)
        {
            return 7;
        }

        var days = (orderedSessions[1].ScheduledAt - orderedSessions[0].ScheduledAt).TotalDays;
        return Math.Max(1, (int)Math.Round(days, MidpointRounding.AwayFromZero));
    }

    private static bool CanPromote(WebSession session) =>
        session.WaitlistedPlayerCount > 0 &&
        (!session.MaxPlayers.HasValue || session.ActivePlayerCount < session.MaxPlayers.Value);

    private static string FormatSeats(WebSession session)
    {
        var seats = session.MaxPlayers.HasValue
            ? $"{session.ActivePlayerCount}/{session.MaxPlayers.Value}"
            : session.ActivePlayerCount.ToString(System.Globalization.CultureInfo.InvariantCulture);

        return session.WaitlistedPlayerCount > 0
            ? $"{seats} · ожидание {session.WaitlistedPlayerCount}"
            : seats;
    }

    private static string FormatBatchSummary(BatchBulkEditModel batch) =>
        $"{batch.SessionCount} игр · {FormatLocalMoscow(batch.FirstScheduledAtLocal)} — {FormatLocalMoscow(batch.LastScheduledAtLocal)}";

    private static string FormatLocalMoscow(DateTime localMoscow) =>
        localMoscow.ToString("d MMMM yyyy, HH:mm", System.Globalization.CultureInfo.GetCultureInfo("ru-RU"));

    private string GetStatusClass(string status) => status switch
    {
        SessionStatus.Confirmed => "status-success",
        SessionStatus.Cancelled => "status-danger",
        SessionStatus.ConfirmationSent => "status-warning",
        SessionStatus.Planned => "status-info",
        _ => "status-neutral"
    };

    private string TranslateStatus(string status) => status switch
    {
        SessionStatus.Planned => "Запланировано",
        SessionStatus.ConfirmationSent => "Ждём подтверждения",
        SessionStatus.Confirmed => "Подтверждено",
        SessionStatus.Cancelled => "Отменено",
        _ => status
    };

    private sealed class BatchBulkEditModel
    {
        public Guid BatchId { get; init; }
        public string Title { get; set; } = "";
        public string JoinLink { get; set; } = "";
        public string NotificationMode { get; set; } = SessionNotificationModeExtensions.GroupAndDirectValue;
        public DateTime FirstScheduledAtLocal { get; set; } = DateTime.Now;
        public DateTime LastScheduledAtLocal { get; init; } = DateTime.Now;
        public int IntervalDays { get; set; } = 7;
        public int SessionCount { get; init; }
        public string CloneInterval { get; set; } = "week";
    }
}