using Dapper;
using GmRelay.Shared.Domain;
using Npgsql;
using Telegram.Bot;
using Telegram.Bot.Types;

namespace GmRelay.Bot.Features.Sessions.ListSessions;

internal sealed record SessionListItemDto(Guid Id, string Title, DateTime ScheduledAt, string Status, int? MaxPlayers, int PlayerCount, int WaitlistCount, bool CanManage);

public sealed class ListSessionsHandler(
    NpgsqlDataSource dataSource,
    ITelegramBotClient botClient)
{
    public async Task HandleAsync(Message message, CancellationToken cancellationToken)
    {
        await using var connection = await dataSource.OpenConnectionAsync(cancellationToken);

        var sessions = await connection.QueryAsync<SessionListItemDto>(
            @"SELECT s.id as Id, s.title as Title, s.scheduled_at as ScheduledAt, s.status as Status, s.max_players as MaxPlayers,
                     COUNT(sp.id) FILTER (WHERE sp.is_gm = false AND sp.registration_status = @Active) as PlayerCount,
                     COUNT(sp.id) FILTER (WHERE sp.is_gm = false AND sp.registration_status = @Waitlisted) as WaitlistCount,
                     EXISTS (
                         SELECT 1
                         FROM group_managers gm
                         JOIN players manager_player ON manager_player.id = gm.player_id
                         WHERE gm.group_id = s.group_id
                           AND manager_player.telegram_id = @TelegramUserId
                     ) AS CanManage
              FROM sessions s
              JOIN game_groups g ON s.group_id = g.id
              LEFT JOIN session_participants sp ON s.id = sp.session_id
              WHERE g.telegram_chat_id = @ChatId AND s.status != @Cancelled AND s.scheduled_at > NOW()
              GROUP BY s.id, s.title, s.scheduled_at, s.status, s.max_players, s.group_id
              ORDER BY s.scheduled_at ASC",
            new
            {
                ChatId = message.Chat.Id,
                TelegramUserId = message.From?.Id,
                Cancelled = SessionStatus.Cancelled,
                Active = ParticipantRegistrationStatus.Active,
                Waitlisted = ParticipantRegistrationStatus.Waitlisted
            });

        var sessionsList = sessions.ToList();

        if (sessionsList.Count == 0)
        {
            await botClient.SendMessage(
                chatId: message.Chat.Id,
                text: "📭 В этой группе нет предстоящих игр.",
                cancellationToken: cancellationToken);
            return;
        }

        var text = "📅 <b>Ближайшие игры:</b>\n\n";
        foreach (var s in sessionsList)
        {
            var seats = s.MaxPlayers.HasValue
                ? $"{s.PlayerCount}/{s.MaxPlayers.Value}"
                : s.PlayerCount.ToString(System.Globalization.CultureInfo.InvariantCulture);
            var waitlist = s.WaitlistCount > 0 ? $", ожидание: {s.WaitlistCount}" : string.Empty;
            text += $"🔹 <b>{s.ScheduledAt.FormatMoscow()}</b> — {System.Net.WebUtility.HtmlEncode(s.Title)} (Места: {seats}{waitlist})\n";
        }

        var canManage = sessionsList.First().CanManage;
        var keyboard = canManage
            ? new Telegram.Bot.Types.ReplyMarkups.InlineKeyboardMarkup(
                sessionsList.Select(s => new[] { Telegram.Bot.Types.ReplyMarkups.InlineKeyboardButton.WithCallbackData($"🗑 Удалить {s.ScheduledAt.FormatMoscowShort()}", $"delete_session:{s.Id}") }))
            : null;

        await botClient.SendMessage(
            chatId: message.Chat.Id,
            text: text,
            parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
            replyMarkup: keyboard,
            cancellationToken: cancellationToken);
    }
}