How to get the list of methods from the receiver at the point of autocompletion?

This is what I currently have:

extend(CompletionType.BASIC, psiElement(), object : CompletionProvider<CompletionParameters>() {
    override fun addCompletions(
        parameters: CompletionParameters,
        context: ProcessingContext,
        result: CompletionResultSet
    ) {
    val receiver = ((parameters.position.parent) as KtSimpleNameExpression).getReceiverExpression()
    result.addElement(LookupElementBuilder.create(""))
   }

})