Function CmdWantEnginePreview

src/engine.cpp:1039–1047

* Accept an engine prototype. XXX - it is possible that the top-company * changes while you are waiting to accept the offer? Then it becomes invalid * @param flags operation to perform * @param engine_id engine-prototype offered * @return the cost of this operation or an error */

 * @return the cost of this operation or an error
 */
CommandCost CmdWantEnginePreview(DoCommandFlags flags, EngineID engine_id)
{
	Engine *e = Engine::GetIfValid(engine_id);
	if (e == nullptr || !e->flags.Test(EngineFlag::ExclusivePreview) || e->preview_company != _current_company) return CMD_ERROR;

	if (flags.Test(DoCommandFlag::Execute)) AcceptEnginePreview(engine_id, _current_company);

	return CommandCost();
}

/**
 * Allow or forbid a specific company to use an engine