using GozareshgirProgramManager.Application._Common.Interfaces;
using GozareshgirProgramManager.Application._Common.Models;
using GozareshgirProgramManager.Application.Modules.TaskChat.DTOs;
using MediatR;
using Microsoft.EntityFrameworkCore;

namespace GozareshgirProgramManager.Application.Modules.TaskChat.Queries.SearchMessages;

public record SearchMessagesQuery(
    Guid TaskId,
    string SearchText,
    int Page = 1,
    int PageSize = 20
) : IBaseQuery<List<MessageDto>>;

public class SearchMessagesQueryHandler : IBaseQueryHandler<SearchMessagesQuery, List<MessageDto>>
{
    private readonly IProgramManagerDbContext _context;
    private readonly IAuthHelper _authHelper;

    public SearchMessagesQueryHandler(IProgramManagerDbContext context, IAuthHelper authHelper)
    {
        _context = context;
        _authHelper = authHelper;
    }

    public async Task<OperationResult<List<MessageDto>>> Handle(SearchMessagesQuery request, CancellationToken cancellationToken)
    {
        var currentUserId = _authHelper.GetCurrentUserId();
        var skip = (request.Page - 1) * request.PageSize;

        var messages = await _context.TaskChatMessages
            .Where(m => m.TaskId == request.TaskId &&
                        m.TextContent != null &&
                        m.TextContent.Contains(request.SearchText) &&
                        !m.IsDeleted)
            .Include(m => m.ReplyToMessage)
            .OrderByDescending(m => m.CreationDate)
            .Skip(skip)
            .Take(request.PageSize)
            .ToListAsync(cancellationToken);

        // ✅ گرفتن تمامی کاربران برای نمایش نام کامل فرستنده
        var senderUserIds = messages.Select(m => m.SenderUserId).Distinct().ToList();
        var users = await _context.Users
            .Where(u => senderUserIds.Contains(u.Id))
            .ToDictionaryAsync(u => u.Id, u => u.FullName, cancellationToken);

        var messageDtos = new List<MessageDto>();
        foreach (var message in messages)
        {
            // ✅ نام فرستنده را از User واقعی بگیر
            var senderName = users.GetValueOrDefault(message.SenderUserId, "کاربر ناشناس");

            var dto = new MessageDto
            {
                Id = message.Id,
                TaskId = message.TaskId,
                SenderUserId = message.SenderUserId,
                SenderName = senderName,
                MessageType = message.MessageType.ToString(),
                TextContent = message.TextContent,
                CreationDate = message.CreationDate,
                IsMine = message.SenderUserId == currentUserId
            };

            messageDtos.Add(dto);
        }

        return OperationResult<List<MessageDto>>.Success(messageDtos);
    }
}