using QMax.Api.Contracts;
using QMax.Api.Data.Entities;

namespace QMax.Api.Services;

public sealed class ChatProjectionService
{
    public ChatDto ToDto(Chat chat)
    {
        return new ChatDto(
            chat.Id,
            chat.ExternalId,
            chat.Kind,
            chat.Title,
            AvatarPath(chat),
            CleanPreview(chat.LastMessagePreview),
            chat.LastMessageAt,
            chat.UnreadCount,
            chat.IsPinned,
            chat.IsMuted,
            chat.IsArchived);
    }

    public MessageDto ToDto(Message message)
    {
        return new MessageDto(
            message.Id,
            message.ChatId,
            message.ExternalId,
            message.SenderName,
            message.Direction,
            MessageTextSanitizer.CleanMessageText(message.Text, message.Attachments.Count != 0),
            message.SentAt,
            message.EditedAt,
            message.DeletedAt,
            message.ReplyToMessageId,
            message.ForwardedFrom,
            message.DeliveryState,
            message.Error,
            message.Reactions
                .GroupBy(x => x.Emoji)
                .OrderByDescending(x => x.Count())
                .ThenBy(x => x.Key, StringComparer.Ordinal)
                .Select(x => new ReactionDto(x.Key, x.Count(), x.Any(r => r.ActorKey == "self")))
                .ToArray(),
            message.Attachments
                .OrderBy(x => x.SortOrder)
                .Select(x => ToDto(message.ChatId, x))
                .ToArray());
    }

    private static AttachmentDto ToDto(Guid chatId, MessageAttachment attachment)
    {
        return new AttachmentDto(
            attachment.Id,
            attachment.OriginalFileName,
            attachment.ContentType,
            attachment.FileSizeBytes,
            $"/api/chats/{chatId}/attachments/{attachment.Id}/content",
            attachment.Kind,
            attachment.SortOrder);
    }

    private static string? CleanPreview(string? value)
    {
        return MessageTextSanitizer.CleanChatPreview(value);
    }

    private static string? AvatarPath(Chat chat)
    {
        return string.IsNullOrWhiteSpace(chat.AvatarUrl)
            ? null
            : $"/api/chats/{chat.Id}/avatar";
    }
}