components/LiteCharms.Features/Shop/Quotes/Commands/Handlers/AssignQuoteToOrderCommandHandler.cs

using LiteCharms.Features.Shop.Postgres;

namespace LiteCharms.Features.Quotes.Commands.Handlers;

public class AssignQuoteToOrderCommandHandler(IDbContextFactory<ShopDbContext> contextFactory) : IRequestHandler<AssignQuoteToOrderCommand, Result>
{
    public async ValueTask<Result> Handle(AssignQuoteToOrderCommand request, CancellationToken cancellationToken)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var order = await context.Orders.FirstOrDefaultAsync(o => o.Id == request.OrderId, cancellationToken);

            if (order is null)
                return Result.Fail(new Error($"Order with id {request.OrderId} not found"));

            if(!await context.Quotes.AnyAsync(q => q.Id == request.OrderId, cancellationToken))
                return Result.Fail(new Error($"Quote with id {request.QuoteId} not found"));

            if(order.QuoteId == request.QuoteId)
                return Result.Fail(new Error($"Quote with id {request.QuoteId} is already assigned to order with id {request.OrderId}"));

            order.QuoteId = request.QuoteId;

            return await context.SaveChangesAsync(cancellationToken) > 0
                ? Result.Ok()
                : Result.Fail(new Error($"Failed to assign quote with id {request.QuoteId} to order with id {request.OrderId}"));
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }
}