// Sweeper.js 120525
const numofrows = 10;
const numofcols = 10;
const mines = 10;
const game=document.getElementById("maingame");
newquestiontext="To get a New Question click the<br /><br /> <div class='button'> Get a Question</div> <br />button";
gameover=0;
clicks=0; // to catch 1st time loser

let board = [];

// preload  images and sounds
   imgbgname=['mine.png','newcup.png','explosion.jpg','map1.jpg','slashsink.jpg','tick.gif','goldbar.jpg'];
   imgbgarray=[];  //declare empty array
   for (i=0;i<imgbgname.length;i++)
       {imgbgarray[i]= new Image();
        imgbgarray[i].src=imgbgname[i];  // force load of image
       }

   soundfiles=['boom.mp3','mine.mp3','win.mp3'];     // preload sound files
   for (i=0;i<soundfiles.length;i++)
       {soundfiles[i]= new Object();}
       

function initializegame() {

    document.getElementById('replay').style.display='none';
    for (let i = 0; i < numofrows; i++)
       {
        board[i] = [];
        for (let j = 0;j < numofcols;j++)
            {// populate object with properties
            board[i][j] = {isMine: false,revealed: false,count: 0,};
            }
       }

    // Place mines randomly
    let minesPlaced = 0;
    while (minesPlaced < mines)
       {
        const row = Math.floor(Math.random() * numofrows);
        const col = Math.floor(Math.random() * numofcols);
        if (!board[row][col].isMine)
           {board[row][col].isMine = true;
            minesPlaced++;
           }
        }

    // Calculate number of mines in surrounding cells and add to cell
    for (let i = 0; i < numofrows; i++)
       {for (let j = 0;j < numofcols;j++)
            {if (!board[i][j].isMine)
                {let count = 0;
                 for (let deltax = -1;deltax <= 1;deltax++)
                     {
                      for (let deltay = -1;deltay <= 1;deltay++)
                          {const ni = i + deltax;
                           const nj = j + deltay;
                           if (ni >= 0 && ni <numofrows &&nj >= 0 &&nj <numofcols &&board[ni][nj].isMine)
                              {count++;}
                          }
                     }
                   board[i][j].count =count;
                 }
            }
       }
}

function allowclick(row, col){

    if(mapcellclick===0&&gameover===0)
      {alertboxer("<h1>Map Access Denied</h1><p>You Must Correctly Answer<br /> a Question before You can <br />Search for Mines!</p>"+newquestiontext);
       //document.getElementById('questionbutton').style.visibility='visible';
       document.getElementById('questionbutton').style.display='block';
	  }
    else {clicks=clicks+1; // keep track of number of clicks to catch 1st click
          revealCell(row, col)}
}

function revealCell(row, col) {
	// out of range or already clicked, ignore
	if (row < 0 ||row >= numofrows ||col < 0 ||col >= numofcols || board[row][col].revealed)
       {return;}

    board[row][col].revealed = true;  // show current cell

    if (board[row][col].isMine) // stepped on  a mine, game over
        {lost();
         return;}

        else if (board[row][col].count === 0)
               {
                //  no mines around cell, show adjacent cells
                for (let deltax = -1;deltax <= 1;deltax++)
                     {
                      for (let deltay = -1;deltay <= 1;deltay++)
                          {revealCell(row + deltax,col + deltay);}
                     }
                }

    displaycells();

    won();   // check for win ?
}

function displaycells(){ // rebuild all cells each time
    game.innerHTML = "";

    for (let i = 0; i < numofrows; i++)
        {
         for (let j = 0;j < numofcols;j++)
            {
             const cell =document.createElement("div");
             cell.className = "mapcell";
            if (board[i][j].revealed)  // if class property is true
               {
                cell.classList.add("revealed");
                if (board[i][j].isMine)
                   {
                    cell.classList.add("mine");
                    cell.innerHTML ="<img src='mine.png' />";
                   } else if (board[i][j].count >0)
                             {cell.textContent = board[i][j].count; }
               }
            cell.addEventListener("click",() => allowclick(i, j));
            game.appendChild(cell);
           }
        game.appendChild(document.createElement("br"));
       }

  // stop clicks on map till question answered correctly
  mapcellclick=0; // reset to needing a question answered
  //document.getElementById('questionbutton').style.visibility='visible';
  document.getElementById('questionbutton').style.display='block';
}

function won(){
   totalcells=0;

   // if all good cells only revealed game won
	  for (let i = 0; i < numofrows; i++)
          {for (let j = 0;j < numofcols;j++)
               {
				if(board[i][j].revealed)  // count non mine cells
                  {totalcells=totalcells+1;
                   goodcells=numofrows*numofcols-mines;
			 	   if(totalcells==goodcells)
			 	     {soundplayer('win');
			 	      revealall();  // show all cells
					  alertboxer("<h1>Game Over!</h1><p>Congratulations</p><img src='newcup.png' /><br />You Located all the Mines and <br />Won the Game.");
					  gameover=1;
				     }
			      }
               }
	      }
}

function lost(){
     
     soundplayer('boom');
     mapcellclick=0;
     revealall(); // show all cells and contents
   	 // hide question button
      document.getElementById('questionbutton').style.display='none';
     // show special message for 1st time loser
      if (clicks==1){losetext=' Your 1st Attempt was Unlucky<br />'}
      else {losetext=''}
	  alertboxer("<h1>Game Over!</h1><img src='explosion.jpg' /><br />"+losetext+"You Hit a Mine!");
	  gameover=1;

}

function revealall(){
	// once game over,  show all cells revealed proprty to true then display
	 for (let i = 0; i < numofrows; i++)
	     {for (let j = 0;j < numofcols;j++)
	          {board[i][j].revealed = true;}
	     }
	 displaycells()
     // document.getElementById('questionbutton').style.visibility='hidden';
	 document.getElementById('questionbutton').style.display='none';
	 document.getElementById('replay').style.display='block';
}

function displayinstructions(){
  if(document.getElementById('instructions').style.display=='block')
      {//document.getElementById('instructions').style.display='none';
       $("#instructions").slideUp("normal");}
  else{//document.getElementById('instructions').style.display='block';
          $("#instructions").slideDown("normal");}
}

function correct(choice){
if (qloaded==1)
   {qloaded=0  // only allow question to be answered once only
    if (choice==answer)  //answer correct
       {mapcellclick=1;  //allow map to be clicked
	    alertboxer("<h1>Correct</h1><br /><img src='tick.gif'/><p>Click a Cell on the Map</p>")
        $("#qdiv").slideUp("normal"); // hide question
       }
  else {
        alertboxer("<h1>Incorrect</h1><p>"+answer+"<br /> was the Correct Answer</p>Try again.<br />"+newquestiontext);
        // let player try a new question
        document.getElementById('questionbutton').style.display='block';
       }
   }
else {alertboxer("<h1>Information</h1><p>Question Already answered.<br />"+newquestiontext+"</p>")}
}


function soundplayer(x){  // use new html audio tag to play mp3s
   document.getElementById("sndplayer").src=x+".mp3";
   document.getElementById("sndplayer").play();
}

function replay(){
// 060525
gameover=0;
aboxtitle='Minesweeper Quiz';
alertsetup();
splashscreen="<img src='splashsink.jpg' />";
alertboxer(splashscreen);
if(typeof title!='string'){title=''} // 220411 - use game title if available
document.getElementById('title').innerHTML=gametitle+" Minesweeper Quiz";

initializegame();
displaycells();
displayinstructions();
mapcellclick=0; // allow click on map when question answered
clicks=0; // to catch 1st time loser
}