Forcing a click where i want

Question

Run my snippet code before you read my question and click on some cells, so you can understand my question better!!

I got Player A = vertical and Player B = horizontal, As you can see, Each click gives turns between each player, moving the green background around some cells, how i can force the players only to be able to click the cells that have green behind them?

note: i tried using $(selector).trigger('click'); (JQuery)

var isCol = 0;
var CellPoint = 0;
var board = [];
var P1 = {
  points: 0
};
var P2 = {
  points: 0
};
for (r = 0; r < 7; r++) {
  var line = [];
  for (c = 0; c < 7; c++) {
    line.push(RandomGenerator(50, 500));
  }
  board.push(line);
}

function prs(curr, c, r) {

  CellPoint = parseInt($(curr).text());

  showTable(curr, c, r);
  isCol = (isCol + 1) % 2;
  clr = isCol ? 'blue' : 'red';
  $(curr).text('S');
  $('#turn').css("color", clr)
    .text(`Player ${(isCol+1)} turn`);
  if (CellPoint) {
    if (isCol) {
      P1.points += CellPoint;
    } else {
      P2.points += CellPoint;
    }
    $('#p1').text(`Player 1: ${P1.points}`);
    $('#p2').text(`Player 2: ${P2.points}`);

  } else {
    console.log('selected S');
  }


}

function toColor(col, row, chosen_col, chosen_row) {
  var ret = false;
  switch (isCol) {
    case 0:
      if (row == chosen_row) {
        ret = true;
      }
      break;
    case 1:
      if (col == chosen_col) {
        ret = true;
      }
      break;
  }
  return ret;
}

function showTable(c, chosen_col, chosen_row) {
  if(c!==-1){board[chosen_row][chosen_col] = 'S';}
  var str = "";
  str += "<table border=1>";
  for (row = 0; row < 7; row++) {
    str += "<tr>";
    for (let col = 0; col < 7; col++) {
      str += "<td onclick='prs(this, " + col + "," + row + ")'";
      
        if(board[row][col]=='S'){
          str += " class=uniqueCell";
        } else{
        if (toColor(col, row, chosen_col, chosen_row)) {
        str += " class='grn' ";} }
     
      str += ">";
      if(board[row][col]=='S') {
        str += 'S';
      } else str += board[row][col];
      str += "</td>";
    }
    str += "</tr>";
  }
  str += "</table>";

  document.getElementById("ff").innerHTML = str;
}

function RandomGenerator(min, max) {
  return Math.floor(Math.random() * (max - min) + min);
}

showTable(-1);

var getUnique = function() {
  var tdElements = document.querySelectorAll('#ff td');
  tdElements[
    RandomGenerator(0, tdElements.length)
  ].classList.add('uniqueCell');
  // update the text of the cell using the class
  document.querySelector('.uniqueCell').textContent = 'S';
};
getUnique();

td {
  border: 2px solid black;
  width: 10px;
  height: 10px;
  text-align: center;
}

td:hover {
  background-color: lightgreen;
}

.grn {
  background-color: green;
  color: white;
}

.turn1 {
  background-color: green;
  color: red;
}

.turn0 {
  background-color: green;
  color: blue;
}

.uniqueCell {
  background-color: tomato;
}

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

  <div><span id='p1' style='color:red;'>Player1: </span>&nbsp; X &nbsp;<span style='color:blue;' id='p2'>Player2: </span></div>

  <p id='turn'>Player 1 turn</p>

  <div id="ff"></div>

Answer 1

I would suggest to use pointer-events. I have added JavaScript logic as well as modified CSS little bit.

in JavaScript I am checking for class .grn, if its available then allowing click everywhere. But if .grn is available then only td with .grn class will be clickable.

See below JavaScript logic.

  if(document.querySelectorAll(".grn").length>0){
    document.getElementById("tbl").classList.add("preventclick");
  }else{
    document.getElementById("tbl").classList.remove("preventclick");
  }

See the Snippet below:

var isCol = 0;
var CellPoint = 0;
var board = [];
var P1 = {
  points: 0
};
var P2 = {
  points: 0
};
for (r = 0; r < 7; r++) {
  var line = [];
  for (c = 0; c < 7; c++) {
    line.push(RandomGenerator(50, 500));
  }
  board.push(line);
}

function prs(curr, c, r) {

  CellPoint = parseInt($(curr).text());

  showTable(curr, c, r);
  isCol = (isCol + 1) % 2;
  clr = isCol ? 'blue' : 'red';
  $(curr).text('S');
  $('#turn').css("color", clr)
    .text(`Player ${(isCol+1)} turn`);
  if (CellPoint) {
    if (isCol) {
      P1.points += CellPoint;
    } else {
      P2.points += CellPoint;
    }
    $('#p1').text(`Player 1: ${P1.points}`);
    $('#p2').text(`Player 2: ${P2.points}`);

  } else {
    console.log('selected S');
  }


}

function toColor(col, row, chosen_col, chosen_row) {
  var ret = false;
  switch (isCol) {
    case 0:
      if (row == chosen_row) {
        ret = true;
      }
      break;
    case 1:
      if (col == chosen_col) {
        ret = true;
      }
      break;
  }
  return ret;
}

function showTable(c, chosen_col, chosen_row) {
  if(c!==-1){board[chosen_row][chosen_col] = 'S';}
  var str = "";
  str += "<table id='tbl' border=1>";
  for (row = 0; row < 7; row++) {
    str += "<tr>";
    for (let col = 0; col < 7; col++) {
      str += "<td onclick='prs(this, " + col + "," + row + ")'";
      
        if(board[row][col]=='S'){
          str += " class=uniqueCell";
        } else{
          if (toColor(col, row, chosen_col, chosen_row)) {
            str += " class='grn' ";
          }
        }
     
      str += ">";
      if(board[row][col]=='S') {
        str += 'S';
      } else str += board[row][col];
      str += "</td>";
    }
    str += "</tr>";
  }
  str += "</table>";

  document.getElementById("ff").innerHTML = str;
  
  if(document.querySelectorAll(".grn").length>0 || document.querySelectorAll(".uniqueCell").length > 1){
    document.getElementById("tbl").classList.add("preventclick");
  }
}

function RandomGenerator(min, max) {
  return Math.floor(Math.random() * (max - min) + min);
}

showTable(-1);

var getUnique = function() {
  var tdElements = document.querySelectorAll('#ff td');
  tdElements[
    RandomGenerator(0, tdElements.length)
  ].classList.add('uniqueCell');
  // update the text of the cell using the class
  document.querySelector('.uniqueCell').textContent = 'S';
};
getUnique();

table#tbl.preventclick td{
  pointer-events: none;
}
td {
  border: 2px solid black;
  width: 10px;
  height: 10px;
  text-align: center;
}

td:hover {
  background-color: lightgreen;
}

.grn {
  background-color: green;
  color: white;
}
table#tbl.preventclick td.grn{
  pointer-events: auto;
}
.turn1 {
  background-color: green;
  color: red;
}

.turn0 {
  background-color: green;
  color: blue;
}

.uniqueCell {
  background-color: tomato;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

  <div><span id='p1' style='color:red;'>Player1: </span>&nbsp; X &nbsp;<span style='color:blue;' id='p2'>Player2: </span></div>

  <p id='turn'>Player 1 turn</p>

  <div id="ff"></div>

Update:

I have added || document.querySelectorAll(".uniqueCell").length > 1 in if condition document.querySelectorAll(".grn").length>0 to fix issue mentioned in comment : there's little problem, try clicking on all the cells, in some cases, where there is no selectable numbers, i can click on anywhere on the S cells