User: beginSocket(ws: Client): void {
    const facilityData: IZSendAlgoFacilityInfo[] = [];
    if (this.facilitiesData.length > 0) {
      this.facilitiesData.forEach((element: IZAlgoFacility) => {
        if (element.zexOperationUnitTms[0] && element.zexFacUnitCosts[0])
          facilityData.push({
            facilityId: element.facUnitCd,
            name: element.facUnitNm,
            address: element.zexSrvcLoc.srvcAddr1,
            openTm: element.zexOperationUnitTms[0].unitDowOpenTm.replace(':', ''),
            closeTm: element.zexOperationUnitTms[0].unitDowCloseTm.replace(':', ''),
            tippingFee: element.zexFacUnitCosts[0].unitCostDispTipFees,
            costPerTon: element.zexFacUnitCosts[0].unitCostDispPerTon,
            srvtTm: element.zexOperationUnitTms[0].srvcUnitTm,
            materialTypId:
              element.zexFacUnitCosts[0].materialTypId == 0 ? null : element.zexFacUnitCosts[0].materialTypId
          });
      });
    }

    const vehiclesData: IZSendAlgoVehicleInfo[] = [];
    if (this.rvData.length > 0) {
      this.rvData.forEach((element: IZAlgoVehicleunit) => {
        vehiclesData.push({
          vehicleId: element.zexVehUnit.vehId,
          size: element.zexVehUnit.vehSizeVal,
          netWeight: element.zexVehUnit.vehNetWtVal,
          compactionRatio: element.zexVehUnit.vehCompRatioVal,
          lunchStartTm: element.zexVehUnit.vehLunchStartTm,
          lunchEndTm: element.zexVehUnit.vehLunchStopTm,
          lunchDuration: element.zexVehUnit.vehLunchTm,
          vehStartTm: element.zexVehUnit.vehStartTm,
          vehStopTm: element.zexVehUnit.vehStopTm,
          vehStartLocId: element.zexVehUnit.vehStartLocId,
          vehEndLocId: element.zexVehUnit.vehEndLocId,
          dow: element.dow
        } as IZSendAlgoVehicleInfo);
      });
    }
    const containerList: { qty: number; size: number }[] = [];
    if (this.containerData.length > 0) {
      this.containerData.forEach((element: IZContainerInfo) => {
        containerList.push({ qty: element.contQty, size: element.contSize });
      });
    }

    let routeConstraintsData: IZRouteConstraints = {} as IZRouteConstraints;
    if (this.routeData[0]) {
      routeConstraintsData = {
        routeBeginTm: this.routeData[0].unitDowOpenTm?.replace(':', ''),
        routeEndTime: this.routeData[0].unitDowCloseTm?.replace(':', ''),
        maxYards: 999999999,
        maxWeight: 999999999,
        maxLifts: 999999,
        maxHours: 15,
        costPerHour: this.routeData[0].costPerHr,
        travelTmFactor: this.routeData[0].odTtmFacVal,
        preTripTm: this.routeData[0].preTripTmSec,
        postTripTm: this.routeData[0].postTripTmSec,
        lunchStartTm: this.routeData[0].lunchStartTm.replace(':', ''),
        lunchEndTm: this.routeData[0].lunchStopTm.replace(':', ''),
        lunchDuration: this.routeData[0].lunchTmSec
      };
    }
    const data: IZCTSAlgoRequest = {
      algType: this.reportName == 'Disposal' ? 'DISPOSAL' : (algoTypeLut[this.commonService.appCode]?.CTS ?? ''),
      userId: this._http.usrId,
      accountId: this._http.accountId,
      opArea: this.opsUnit,
      routeType: this.routeType,
      routes: [],
      algoRequestCommonParam: { stops: this.stops, lifts: this.lifts, weight: this.weight, volume: this.yards },
      routeConstraints: routeConstraintsData,
      facilities: facilityData,
      vehicleList: vehiclesData,
      containerList,
      isRequestAgain: this.isReqForSmAlgAgnRn,
      //ZRP-2418 - Added below params for Cost To Serve to use DLO for cost and time calculation
      dbgCollapseOption: 2,
      optimizeFlag: this.optimizedBy,
      minPctFull: 10,
      maxPctAllowance: 0,
      honorCustomerTimeWindows: 'Y',
      honorLoadNo: 'N',
      mustDisposalFlag: 'N',
      clusterByLoad: 'Y',
      keepRouteNo: 'Y',
      keepSequenceNo: 'Y'
    };
    if (this.reportName == 'Disposal' && this.reportTypeInfo.type == 'RT') {
      data.dowList = [];
    } else {
      if (this.dow.length) {
        data.dowList = this.dow;
      }
    }
    this.startTime = new Date();
    this.refreshTime = this.startTime;
    const secs: number = this.commonService.getTimeDifferenceInSeconds(this.refreshTime, this.startTime);
    this.duration = this._http.convertSecsIntoMins(secs);
    ws.send('/app/startJob', {}, JSON.stringify(data));
  }

make one change in this our element.zexFacUnitCosts[0] contains multiple onject i want to loop over those and add entry for each object in facilitydata and push
Assistant: To modify the existing code so that it loops over the multiple objects in `element.zexFacUnitCosts` and adds an entry for each object in `facilityData`, you will need to change the relevant section of the `beginSocket` method. Here's how you can do this:

1. Remove the check for `element.zexFacUnitCosts[0]`.
2. Loop through `element.zexFacUnitCosts` and push an entry into `facilityData` for each object present.

Here's the adjusted code:

```typescript
beginSocket(ws: Client): void {
    const facilityData: IZSendAlgoFacilityInfo[] = [];
    if (this.facilitiesData.length > 0) {
        this.facilitiesData.forEach((element: IZAlgoFacility) => {
            if (element.zexOperationUnitTms[0] && element.zexFacUnitCosts.length > 0) {
                element.zexFacUnitCosts.forEach(cost => {
                    facilityData.push({
                        facilityId: element.facUnitCd,
                        name: element.facUnitNm,
                        address: element.zexSrvcLoc.srvcAddr1,
                        openTm: element.zexOperationUnitTms[0].unitDowOpenTm.replace(':', ''),
                        closeTm: element.zexOperationUnitTms[0].unitDowCloseTm.replace(':', ''),
                        tippingFee: cost.unitCostDispTipFees,
                        costPerTon: cost.unitCostDispPerTon,
                        srvtTm: element.zexOperationUnitTms[0].srvcUnitTm,
                        materialTypId: cost.materialTypId == 0 ? null : cost.materialTypId
                    });
                });
            }
        });
    }

    const vehiclesData: IZSendAlgoVehicleInfo[] = [];
    if (this.rvData.length > 0) {
        this.rvData.forEach((element: IZAlgoVehicleunit) => {
            vehiclesData.push({
                vehicleId: element.zexVehUnit.vehId,
                size: element.zexVehUnit.vehSizeVal,
                netWeight: element.zexVehUnit.vehNetWtVal,
                compactionRatio: element.zexVehUnit.vehCompRatioVal,
                lunchStartTm: element.zexVehUnit.vehLunchStartTm,
                lunchEndTm: element.zexVehUnit.vehLunchStopTm,
                lunchDuration: element.zexVehUnit.vehLunchTm,
                vehStartTm: element.zexVehUnit.vehStartTm,
                vehStopTm: element.zexVehUnit.vehStopTm,
                vehStartLocId: element.zexVehUnit.vehStartLocId,
                vehEndLocId: element.zexVehUnit.vehEndLocId,
                dow: element.dow
            } as IZSendAlgoVehicleInfo);
        });
    }

    const containerList: { qty: number; size: number }[] = [];
    if (this.containerData.length > 0) {
        this.containerData.forEach((element: IZContainerInfo) => {
            containerList.push({ qty: element.contQty, size: element.contSize });
        });
    }

    let routeConstraintsData: IZRouteConstraints = {} as IZRouteConstraints;
    if (this.routeData[0]) {
        routeConstraintsData = {
            routeBeginTm: this.routeData[0].unitDowOpenTm?.replace(':', ''),
            routeEndTime: this.routeData[0].unitDowCloseTm?.replace(':', ''),
            maxYards: 999999999,
            maxWeight: 999999999,
            maxLifts: 999999,
            maxHours: 15,
            costPerHour: this.routeData[0].costPerHr,
            travelTmFactor: this.routeData[0].odTtmFacVal,
            preTripTm: this.routeData[0].preTripTmSec,
            postTripTm: this.routeData[0].postTripTmSec,
            lunchStartTm: this.routeData[0].lunchStartTm.replace(':', ''),
            lunchEndTm: this.routeData[0].lunchStopTm.replace(':', ''),
            lunchDuration: this.routeData[0].lunchTmSec
        };
    }

    const data: IZCTSAlgoRequest = {
        algType: this.reportName == 'Disposal' ? 'DISPOSAL' : (algoTypeLut[this.commonService.appCode]?.CTS ?? ''),
        userId: this._http.usrId,
        accountId: this._http.accountId,
        opArea: this.opsUnit,
        routeType: this.routeType,
        routes: [],
        algoRequestCommonParam: { stops: this.stops, lifts: this.lifts, weight: this.weight, volume: this.yards },
        routeConstraints: routeConstraintsData,
        facilities: facilityData,
        vehicleList: vehiclesData,
        containerList,
        isRequestAgain: this.isReqForSmAlgAgnRn,
        // ZRP-2418 - Added below params for Cost To Serve to use DLO for cost and time calculation
        dbgCollapseOption: 2,
        optimizeFlag: this.optimizedBy,
        minPctFull: 10,
        maxPctAllowance: 0,
        honorCustomerTimeWindows: 'Y',
        honorLoadNo: 'N',
        mustDisposalFlag: 'N',
        clusterByLoad: 'Y',
        keepRouteNo: 'Y',
        keepSequenceNo: 'Y'
    };

    if (this.reportName == 'Disposal' && this.reportTypeInfo.type == 'RT') {
        data.dowList = [];
    } else {
        if (this.dow.length) {
            data.dowList = this.dow;
        }
    }

    this.startTime = new Date();
    this.refreshTime = this.startTime;
    const secs: number = this.commonService.getTimeDifferenceInSeconds(this.refreshTime, this.startTime);
    this.duration = this._http.convertSecsIntoMins(secs);
    ws.send('/app/startJob', {}, JSON.stringify(data));
}
```

### Key Changes
- **Loop Through `element.zexFacUnitCosts`:** A `forEach` loop is added to iterate through `element.zexFacUnitCosts` and push a new entry to `facilityData` for each cost object.
- **Removed Single Check:** The check for only the first element (`[0]`) in `zexFacUnitCosts` is removed to accommodate all cost objects.

Now, each cost in `zexFacUnitCosts` will create a corresponding entry in `facilityData`, allowing you to send multiple entries for each facility when the socket message is sent.
User: getting this Object is possibly 'undefined'.ts(2 for element.zexOperationUnitTms[0]
Assistant:  error message you're encountering, "Object is possibly 'undefined'.ts(2345)", indicates that TypeScript believes there's a possibility that `element.zexOperationUnitTms[0]` or any other property you are accessing might be `undefined`. To resolve this, you can use optional chaining, which will safely access the properties without throwing an error if any object in the chain is `undefined`.

Here's the modified section of your code that incorporates optional chaining and ensures there are checks before accessing properties on potentially undefined objects:

```typescript
beginSocket(ws: Client): void {
    const facilityData: IZSendAlgoFacilityInfo[] = [];
    if (this.facilitiesData.length > 0) {
        this.facilitiesData.forEach((element: IZAlgoFacility) => {
            const operationUnitTm = element.zexOperationUnitTms[0];
            const facUnitCosts = element.zexFacUnitCosts;

            if (operationUnitTm && Array.isArray(facUnitCosts) && facUnitCosts.length > 0) {
                facUnitCosts.forEach(cost => {
                    facilityData.push({
                        facilityId: element.facUnitCd,
                        name: element.facUnitNm,
                        address: element.zexSrvcLoc?.srvcAddr1 ?? '',  // Use optional chaining
                        openTm: operationUnitTm.unitDowOpenTm.replace(':', ''),
                        closeTm: operationUnitTm.unitDowCloseTm.replace(':', ''),
                        tippingFee: cost.unitCostDispTipFees,
                        costPerTon: cost.unitCostDispPerTon,
                        srvtTm: operationUnitTm.srvcUnitTm,
                        materialTypId: cost.materialTypId == 0 ? null : cost.materialTypId
                    });
                });
            }
        });
    }

    // The rest of your method continues here...
}
```

### Key Changes

1. **Optional Chaining (`?.`)**: This has been added for properties that can potentially be `undefined`. For example, `address: element.zexSrvcLoc?.srvcAddr1 ?? ''` uses optional chaining to access `srvcAddr1` safely. If `zexSrvcLoc` is `undefined`, an empty string is used as a fallback.

2. **Array Check**: I included a check to ensure that `facUnitCosts` is an array and has at least one element before proceeding with the `forEach` loop. This helps avoid errors when accessing `length`.

3. **Operation Unit Check**: I also stored `element.zexOperationUnitTms[0]` in a variable (`operationUnitTm`) to avoid accessing it multiple times and to improve readability.

By making these adjustments, the possibility of encountering an `undefined` error is mitigated, and your code should be more robust. Make sure to apply similar logic throughout your method where you need to safely access properties on objects that might not always be defined.
User: there is some bug when i select option A and then select option B the checked property of A becoe false instead both should be true
<li
          *ngIf="btn.functionType === 'dropdown' && btn.enableMultiSelectLabelByStatus"
          [ngStyle]="{ display: btn.isActive ? 'block' : 'none' }"
          class="btn tooltip"
          (click)="toogleDropdown($event, btn)"
        >
          <label *ngIf="btn.name === 'labelBy'" class="select-label">{{ btn.displayText }}</label>
          <input
            *ngIf="btn.name === 'labelBy'"
            readonly
            [(ngModel)]="selectedLabelByString"
            [ngClass]="btn.className"
            class="labelBy-inputBox"
            id="{{ btn.name }}"
          />
          <i *ngIf="btn.name === 'labelBy'" class="fas fa-angle-down labelBy-Arrow"></i>
          <i *ngIf="btn.name === 'facility'" [ngClass]="btn.className"></i>

          <ul
            *ngIf="btn.functionType === 'dropdown'"
            id="{{ btn.name }}"
            class="switcher"
            [ngClass]="{ isSwitcherActive: btn.name === 'labelBy' ? showCheckboxes : facilityToggle }"
            (mouseleave)="btn.name === 'labelBy' ? (showCheckboxes = false) : (facilityToggle = false)"
          >
            <!-- "$event.stopPropagation()" is used to prevent the dropdown from closing when user clicks on checkboxes -->
            <li
              *ngFor="let opt of btn.options; trackBy: trackByFunction"
              [ngClass]="{ selectedOption: opt?.checked }"
              [ngStyle]="{ display: 'flex', gap: '2px' }"
              (click)="$event.stopPropagation()"
            >
              <input
                type="checkbox"
                [attr.value]="opt.value"
                [attr.name]="opt.name"
                id="{{ btn.name }}_{{ opt.value }}"
                [checked]="opt?.checked"
                [disabled]="opt.disable"
                (change)="btn.name === 'labelBy' ? checkLabelBy($event, btn, opt) : checkFacility($event, btn, opt)"
                style="flex-shrink: 0"
              />
              <label class="checkboxLabel" for="{{ btn.name }}_{{ opt.value }}">{{ opt.name }}</label>
            </li>
          </ul>
        </li>
Assistant: