Magic squares of odd order

# title: Magic squares of odd order
# source: https://rosettacode.org/wiki/Magic_squares_of_odd_order
# category: Rosetta Code
# difficulty: Medium
# summary: Build a 3x3 magic square with the classic Siamese method.
# tags: popular, matrices, math, algorithms
# vibe: 0.2

def blank_square(size)
  rows = []
  row = 0
  while row < size
    current = []
    column = 0
    while column < size
      current = current.push(0)
      column = column + 1
    end
    rows = rows.push(current)
    row = row + 1
  end
  rows
end

def set_cell(square, row, column, value)
  current = square[row]
  current[column] = value
  square[row] = current
  square
end

def magic_square(size)
  square = blank_square(size)
  row = 0
  column = size / 2
  value = 1

  while value <= size * size
    square = set_cell(square, row, column, value)
    next_row = row - 1
    next_column = column + 1

    if next_row < 0
      next_row = size - 1
    end
    if next_column >= size
      next_column = 0
    end

    if square[next_row][next_column] != 0
      row = row + 1
      if row >= size
        row = 0
      end
    else
      row = next_row
      column = next_column
    end

    value = value + 1
  end

  square
end

def run
  magic_square(3)
end