$scope function and ng-disable not functioning

Question

Below is the JS of my angular JS Web App:

$scope.total = 50000000;

var ref = databaseService.players;


$scope.players = $firebaseArray(ref);


$scope.picked = [];
$scope.history = [];

 $scope.buy = function(player) {
        //remove if already added locally
        var index = $scope.history.indexOf(player);
        var index2 = $scope.picked.indexOf(player.id);
        if(index>=0 || index2>=0 ){
            $scope.history.splice(index,1);
            $scope.picked.splice(index2,1);
            PlayerService.removePlayerFromSelection(player);
            return;
        }

        //max 6 allowed
        if($scope.history.length>=6 || $scope.picked.length>=6){
            alert('max 6 allowed');
            return;
        }
        //to make sure moeny doesn't go below $50,000,000
        if($scope.total<0){
            alert('Oops! You have run out of cash');
            return;
        }

        var selected = $scope.history.reduce(function(a,b){
            a[b.position] = (a[b.position] || 0) + 1;
            return a;
        }, {}) || {};

        if(!selected[player.position] || selected[player.position]<2 && $scope.total>0){
            $scope.history.push(player);
            $scope.picked.push(player.id);
            PlayerService.addPlayerToSelection(player);       
        }else{
            alert('You can add only two players per position');

        }
      };

      $scope.getTotal = function(){
        return $scope.history.reduce(function(tot, p){
            tot = tot - p.price;
            return tot;
            if (tot <0){
                alert('Oops! You have run out of money')
            }
        }, $scope.total);
      }; 
  $scope.saveTeam = function(){
   userRef.set( $scope.picked);       
   $location.path('/mySquad');
   };

MY issue

Is there a way to alert the user when the total goes lower than 0? I tried adding an if statement into the buy() function but it did not work. I aim to have the user alerted when the total budget goes below 0.

Alternative

Another option i tired is to have the "save team" button disabled if the result of the function getTotal results in a value less than 0. Below is the HTML code i tried but was unsuccessful with:

 <button type="submit" class="btn btn-lg btn-primary btn-md " ng-disabled="history.length<6" ng-disabled="getTotal<0" ng-click="saveTeam()" > Save Team </button>

Answer 1

Can you try to rewrite the function as below. You need to change the place for return statement

$scope.getTotal = function(){
        return $scope.history.reduce(function(tot, p){
            tot = tot - p.price;

            if (tot <0){
                alert('Oops! You have run out of money')
            }
           return tot; //changed location of this line
        }, $scope.total);
      };