Sudoku solver with everything but final solve method working

Sudoku v1, incomplete

class Board

  def initialize(board_input)
    @board_array = []
    board_input.split(//).each_with_index do |cell, index|
      @board_array << Cell.new(cell, index)
    end
  end

  def find_box(cell_id)
    ((cell_id % 9) / 3) + ((cell_id / 27) * 3)
   end

  def box_fill(cell_id)
    @current_box = []
    @box_id = find_box(cell_id)
    @board_array.select do |cell|
      if find_box(cell.id) == @box_id
        @current_box << cell.value
      end
    end
    @current_box
  end

  def find_row(cell_id)
    cell_id / 9
  end

  def row_fill(cell_id)
    @current_row = []
    @row_id = find_row(cell_id)
    @board_array.select do |cell|
      if find_row(cell.id) == @row_id
        @current_row << cell.value
      end
    end
    @current_row
  end

  def find_column(cell_id)
    cell_id % 9
  end

  def column_fill(cell_id)
    @current_column = []
    @column_id = find_column(cell_id)
    @board_array.select do |cell|
      if find_column(cell.id) == @column_id
        @current_column << cell.value
      end
    end
    @current_column
  end

  def solve
    current = @board_array.each do |cell|
      cell.value
    end
      if current.include? 0
        @board_array.each do |cell|
            if cell.value == 0
                neighbors = (box_fill(cell.id) | column_fill(cell.id) |
                row_fill(cell.id))
                all = [1,2,3,4,5,6,7,8,9]
                options = all - neighbors
                  if options.length == 1
                    cell.update(options[0])
                  end
            end
          end
        # else
        #          puts @board_array.each do |cell|
        #            cell.value
        # end
      end
  end


end

class Cell

  attr_accessor :value, :id

  def initialize(value, id)
    @value = value
    @id = id
  end

  def update(new_value)
    @value = new_value
  end

end

board = Board.new("619030040270061008000047621486302079000014580031009060005720806320106057160400030")
board.solve