class Maze{
	constructor(mazeWidth, mazeHeight, cellWidth){
		this.columns = floor(mazeWidth / cellWidth);
		this.rows = floor(mazeHeight / cellWidth);
		this.width = mazeWidth;
		this.height = mazeHeight;
		this.cellWidth = cellWidth;
		this.workingStack = [];
		this.currentCell = {};
		this.grid = [];
		
	    for (let y = 0; y < this.rows; y++) {
			for (var x = 0; x < this.columns; x++) {
		  		this.grid.push(new Cell(x, y, this.cellWidth));
			}
	    }
	    
	    this.grid[this.index(0,0)].visited = true;
	    this.grid[this.index(0,0)].selected = true;
	    this.workingStack.push(this.grid[this.index(0,0)]);
	}
	
	updateMazeDisplay(){
	  for (var i = 0; i < this.grid.length; i++) {
		this.grid[i].show();
	  }
	}
	
	buildNextCell(){
	  	//Build the maze
		this.currentCell = this.workingStack.pop();
		//currentCell.visited = true;
	  	let nextCell = getNeighbors(this.currentCell);
	  	
	  	if(nextCell){
		   	this.workingStack.push(this.currentCell);
		  	currentCell.Selected = false;
		  	currentCell.visited = true;
		  	nextCell.visited = true;
		  	nextCell.selected = true;
	  		removeWalls(currentCell, nextCell);
	  		this.workingStack.push(nextCell);
	  	} 
	  	else 
	  		this.workingStack.pop();
	  	
	  	this.currentCell.selected = false;	
	}
	
	get mazeGenDone() {
		return this.workingStack.length == 0;
	}
	
	getNeighbors(cell){
		var visited = [];
		
		var top = this.grid[index(cell.x, cell.y - 1)];
		var left = this.grid[index(cell.x - 1, cell.y)];
		var bottom = this.grid[index(cell.x, cell.y + 1)];
		var right = this.grid[index(cell.x + 1, cell.y)];
		
		if (top && !top.visited) {
		  visited.push(top);
		}
		if (left && !left.visited) {
		  visited.push(left);
		}
		if (right && !right.visited) {
		  visited.push(right);
		}
		if (bottom && !bottom.visited) {
		  visited.push(bottom);
		}
		
		if(visited.length == 1) 
			return visited[0];
		else if (visited.length > 1)
		  	return visited[floor(random(0, visited.length))];
		else 
			return undefined;
	}	

	index(x, y) {
	  if (x < 0 || y < 0 || x > this.columns - 1 || y > this.rows - 1) return -1;
	  return x + y * this.columns;
	}
	
}