private def prepareCallback()

in nlpcraft/src/main/scala/org/apache/nlpcraft/internal/impl/NCModelScanner.scala [336:368]
22 lines of code
12 McCabe index (conditional complexity)

    private def prepareCallback(cfg: NCModelConfig, method: Method, obj: AnyRef, intent: NCIDLIntent): NCCallbackInput => NCResult =
        lazy val z = s"mdlId=${cfg.getId}, intentId=${intent.id}, type=${class2Str(method.getReturnType)}, callback=${method2Str(method)}"

        // Checks method result type.
        if method.getReturnType != CLS_QRY_RES && !CLS_QRY_RES.isAssignableFrom(method.getReturnType) then
            E(s"Unexpected result type for @NCIntent annotated method [$z]")

        val allParamTypes = method.getParameterTypes.toList

        if allParamTypes.sizeIs < 2 then E(s"Unexpected parameters count for $I annotated method [count=${allParamTypes.size}, method=$z]")
        if allParamTypes.head != CLS_CTX then E(s"First parameter for $I annotated method must be NCContext [method=$z]")
        if allParamTypes(1) != CLS_INTENT_MATCH then E(s"Second parameter for $I annotated method must be NCIntentMatch [method=$z]")

        val tokParamAnns = method.getParameterAnnotations.toList.drop(2).filter(_ != null)
        val tokParamTypes = allParamTypes.drop(2)

        // Checks entities parameters annotations count.
        if tokParamAnns.sizeIs != tokParamTypes.length then
            E(s"Unexpected annotations count for $I annotated method [count=${tokParamAnns.size}, $z]")

        // Gets terms IDs.
        val termIds = tokParamAnns.zipWithIndex.map {
            case (annArr, idx) =>
                val termAnns = annArr.filter(_.isInstanceOf[NCIntentTerm])

                // Each method arguments (second and later) must have one 'NCIntentTerm' annotation.
                termAnns.length match
                    case 1 => termAnns.head.asInstanceOf[NCIntentTerm].value
                    case 0 =>
                        if idx == 0 then E(s"Missing $IT annotation or wrong type of the 1st parameter (must be 'NCIntentMatch') for [$z]")
                        else E(s"Missing $IT annotation for [$z]")
                    case _ => E(s"Too many $IT annotations for [$z]")
        }