smartclone/force-app/main/default/lwc/opportunityCustomClone/opportunityCustomClone.js

import { LightningElement, api, wire, track } from 'lwc';
import { getObjectInfo } from 'lightning/uiObjectInfoApi';
import { getRecord } from 'lightning/uiRecordApi';
import { NavigationMixin} from 'lightning/navigation';
import OPPORTUNITY_OBJECT from '@salesforce/schema/Opportunity';
import ObtainCloneOpportunityFields from '@salesforce/apex/OpportunityCloneService.ObtainCloneOpportunityFields';
import ObtainChildRelationships from '@salesforce/apex/OpportunityCloneService.ObtainOpporunityChildRelationships';
import CloneOpportunityWithChildren from '@salesforce/apex/OpportunityCloneService.CloneOpportunityWithChildren';

export default class OpportunityCustomClone extends NavigationMixin(LightningElement) {
    @api recordId;

    formObjectApiName;
    displayedFields;
    requiredFieldMap;
    opportunityFields;
    childRelationshipList;
    recordInfo;
    childRelationshipDisplayList = [];
    @track childRelationshipSelectionList = [];

    @wire(getRecord,{recordId:'$recordId',layoutTypes:['Full'],modes:['Edit']})
    processRecordInfo({err, data}) {
        if(err) {
            window.console.error('There was a problem obtaining Opportunity Record Data');
            window.console.error(err);
        }

        if(data) {
            //window.console.log('Original Data: %s',JSON.stringify(data,null,"\t"));
            this.recordInfo = data.fields;
        }
    }

    @wire(ObtainChildRelationships)
    processChildRelationships({error, data}) {
        if(error) {
            window.console.log('There is an error obtaining Cild Relationships');
            window.console.error(error);
        }

        if(data) {
            var childRelationshipPicklistArray = [];
            Object.keys(data).forEach(childItem => {
                childRelationshipPicklistArray.push({'label':data[childItem],'value':childItem});
            })
            this.childRelationshipDisplayList = childRelationshipPicklistArray;
        }
    }

    @wire(ObtainCloneOpportunityFields,{fieldsetName:'ClonedFields'})
    processFieldsetInfo({error, data}) {
        if(error){
            window.console.error('There is an error obtaining ClonedFields fieldset');
            window.console.error(error);
        }
        if(data){
            this.displayedFields = Object.keys(data);
            this.requiredFieldMap = data;
        }
    }
    
    @wire(getObjectInfo,{ objectApiName: OPPORTUNITY_OBJECT })
    processOpportunityObjectInfo({error, data}) {
        if(error){
            window.console.error('There is an error obtaining fields');
        }
        if(data){
            this.formObjectApiName = OPPORTUNITY_OBJECT.objectApiName;
            this.opportunityFields = data.fields;
        }
    }
    /**
     * @description                 Handler that executes on selection of child Relationship
     */
    handleChildRelationshipSelection(evt){
        //find the item that was selected from the distplay list
        var selectedItem = evt.target.value;
        let fullSelectedList = this.childRelationshipSelectionList;
        let displayList = this.childRelationshipDisplayList;
        let chosenObj = displayList.find( element => element.value === selectedItem);
        let alreadySelected = fullSelectedList.findIndex(element => element.value === selectedItem);
        window.console.log('Already Selected Value: %s',alreadySelected);
        if(chosenObj && alreadySelected < 0){
            fullSelectedList.push(chosenObj);
        }
        this.childRelationshipSelectionList = fullSelectedList;
        window.console.log('Full Selected List: %s',JSON.stringify(this.childRelationshipSelectionList,null,"\t"));
    }

    handleChildSelectionRemoval(evt){
        window.console.log('Item Clicked: %s',evt.detail.index);
        let fullSelectedList = this.childRelationshipSelectionList;
        let removedItem = fullSelectedList.splice(evt.detail.index,1);
        this.childRelationshipSelectionList = fullSelectedList;
    }
    /**
     * @description                 This will override the submission
     * @param {*} evt 
     */
    handleSubmit(evt){
        evt.preventDefault();
        var fields = evt.detail.fields;
        var childRelList = [];
        this.childRelationshipSelectionList.forEach( selection => {
            childRelList.push(selection.value);
        });
        window.console.log('Child Relationships Selected: %s',JSON.stringify(childRelList,null,"\t"));
        CloneOpportunityWithChildren({'oppId':this.recordId,'newValues':fields,'childRelationshipsToClone':childRelList})
            .then((results)=>{
                window.console.log('Successful callout. %s',JSON.stringify(results,null,"\t"));
                this.sendToOpp(results);
            })
            .catch((err)=>{
                window.console.log('There was an error attempting to clone records.');
            });
    }
    sendToOpp(oppId){
        window.console.log('Send to Opp executed.');
        this[NavigationMixin.Navigate]({
            type:'standard__recordPage',
            attributes:{
                recordId:oppId,
                objectApiName:OPPORTUNITY_OBJECT.objectApiName,
                actionName:'view'
            }
        });
    }

    get formFields(){
        var formFieldsToReturn = [];
        var fieldRequirementMap = this.requiredFieldMap;
        if(this.opportunityFields && this.displayedFields && this.recordInfo) {
            window.console.log('fieldInfo %s: ', JSON.stringify(this.recordInfo,null,"\t"));
            this.displayedFields.forEach(fieldName => { 
                let fieldItem = fieldRequirementMap[fieldName];
                let fieldDisplay = JSON.parse(JSON.stringify(this.opportunityFields[fieldName]));
                if(!fieldItem){
                    fieldDisplay.value = this.recordInfo[fieldName].value;
                }
                formFieldsToReturn.push(fieldDisplay);
            });
        }
        return formFieldsToReturn;
    }
}