using AutoMapper;
using MediatR;
using Mws.Application.Common;

namespace Mws.Application.Tasks;

public record UpdateTaskCommand(Guid UserId, Guid TaskId, UpdateTaskRequest Request) : IRequest<TaskDto>;

public class UpdateTaskHandler(IUnitOfWork uow, IMapper mapper) : IRequestHandler<UpdateTaskCommand, TaskDto>
{
    public async Task<TaskDto> Handle(UpdateTaskCommand command, CancellationToken ct)
    {
        var task = await TaskAccess.GetTaskForUserAsync(uow, command.UserId, command.TaskId, ct);

        var request = command.Request;
        if (string.IsNullOrWhiteSpace(request.Title))
        {
            throw new BadRequestException("Task title is required");
        }

        if (request.AssigneeId.HasValue && !await uow.Projects.IsMemberAsync(task.ProjectId, request.AssigneeId.Value, ct))
        {
            throw new BadRequestException("Assignee must be a member of the project");
        }

        task.Title = request.Title.Trim();
        task.Description = request.Description;
        task.Status = request.Status;
        task.Priority = request.Priority;
        task.AssigneeId = request.AssigneeId;
        task.DueDate = request.DueDate;
        task.UpdatedAt = DateTime.UtcNow;

        await uow.SaveChangesAsync(ct);
        return await TaskAccess.GetDtoAsync(uow, mapper, task.Id, ct);
    }
}