A Javascript solution for https://github.com/blakeembrey/code-problems/tree/master/problems/spiral

gistfile1.js

//A Javascript solution for https://github.com/blakeembrey/code-problems/tree/master/problems/spiral
function f(m, n, x, y) {
   var ans = [], endRecurse = false, arr;
    var recurse = function(stride, curX, curY) {
        var i, j;
        if(endRecurse) { return; }
        
        addColumnOrRow(true, curY, curX - 1, curX - stride); 
        addColumnOrRow(false, curX - stride, curY - 1, curY - stride);
        
        addColumnOrRow(true, curY - stride, curX - stride + 1, curX + 1);
        addColumnOrRow(false, curX + 1, curY - stride + 1, curY + 1);

        recurse(stride + 2, curX + 1, curY + 1);
    };
    var add = function(i, j) {
        if((i == 0) && (j == (n-1))) { endRecurse = true; }
        if(arr[i] && arr[i][j]) { ans.push(arr[i][j]); }
    };
    var addColumnOrRow = function(isCol, colOrRow, start, end) {
        var i, inc = 1, rev = false; 
        if(start > end) {
            inc = -1;
            rev = true;
        }
        for(i = start; (rev ? i >= end : i <= end); i += inc) {
            if(isCol) {
                add(i, colOrRow);
            } else {
                add(colOrRow, i);
            }
        }
    };
    var createArray = function(m, n) { 
        var i = 0, j = 0, a = [], cnt = 1, tmp; 
        for(i = 0; i < m; i++) { 
            tmp = []; 
            for(j = 0; j < n; j++) { tmp.push(cnt++); }; 
            a.push(tmp); } 
        return a; 
    };
    arr = createArray(m, n);
    x--;
    y--;
    add(x, y);
    recurse(1, x, y);
    return ans;
}