mozo-backend/app/models/section.rb

class Section
  include SimplyStored::Couch

  property :title
  property :path, type: Array, default: []

  belongs_to :supplier
  has_many :tables
  has_many :lists
  has_many :orders

  attr_protected :supplier_id

  validates :title, presence: true
  validates :supplier_id, presence: true

  view :by_supplier_id_and_id, key: [:supplier_id, :_id]

  def occupied_tables
    return @occupied_tables if @occupied_tables.present?
    @active_lists = List.active_for_section(self.id)
    @active_lists.include_relation(:table)
    @occupied_tables = @active_lists.map(&:table)
  end

  def active_lists
    return @active_lists if @active_lists.present?
    @active_lists = List.active_for_section(self.id)
  end


  def width
    self.path.last.try(:first).to_f - self.path.first.try(:first).to_f
  end
  def height 
    self.path.last.try(:last).to_f - self.path.first.try(:last).to_f
  end

  def width=(val)
    val = val.to_f
    self.path[0] ||= [0.0, 0.0]
    self.path[1] ||= [0.0, 0.0]
    unless path[1][0] == val
      self.path[1][0] = val 
      path_will_change!
    end
  end
  def height=(val)
    val = val.to_f
    self.path[0] ||= [0.0, 0.0]
    self.path[1] ||= [0.0, 0.0]
    unless path[1][1] == val
      self.path[1][1] = val 
      path_will_change!
    end
  end

  def as_json
    super.merge(width: width, height: height)
  end

  def for_tables_as_json
    return @for_tables_as_json if @for_tables_as_json.present?
    h = as_json
    h[:tables] = []
    for table in tables
      ht = table.as_json
      ht[:occupied] = occupied_tables.include?(table)
      ht[:needs_help] = ht[:occupied] ? active_lists.find{|l| l.table_id == table.id}.try(:needs_help).present? : false
      ht[:needs_payment] = ht[:occupied] ? active_lists.find{|l| l.table_id == table.id}.try(:needs_payment).present? : false
      h[:tables] << ht
    end
    @for_tables_as_json = h
  end

  def arrange_tables_in_grid
    w = width
    h = height
    n = tables.size
    l = Math.sqrt((w*h).to_f/n)
    epsilon = (10 ** -(Float::DIG - 1)).to_f
    while (w/l).floor * (h/l).floor < n # find a fitting combination
      l = if w.remainder(l) < epsilon then (h/l).ceil
      elsif h.remainder(l) < epsilon then (w/l).ceil
      elsif w.remainder(l) < epsilon && h.remainder(l) < epsilon then [w / (w/l).ceil.succ, h / (h/l).ceil.succ].max # Failsafe for when both are valid and it still does not fit
      else [w / (w/l).ceil, h / (h/l).ceil].max end
    end
    x0 = w.remainder(l - epsilon)/2 # Start with half a remainder space, will end with the other halve
    x = x0
    y = h.remainder(l - epsilon)/2
    saves = []
    for table in tables.sort_by(&:number)
      if x + l > w + (1e4*epsilon) # New row,  error = epsilon times possible tables
        x = x0
        y += l
      end
      table.position_x = x + (l/2) - (table_width/2) # Starting point of square + half the square (center) minus half the table size
      table.position_y = y + (l/2) - (table_height/2)
      saves << table.save
      x += l
    end
    [l, saves.all?]
  end

  def arrange_tables_in_rows_of(n)
    return unless n.present?
    n = n.to_i
    return unless n > 0
    dx = width / n
    dy = height / (tables.size.to_f/n).ceil
    x = 0.0
    y = 0.0
    tables.sort_by(&:number).each.with_index do |table, i|
      table.position_x = x + (dx/2) - (table_width/2)
      table.position_y = y + (dy/2) - (table_height/2)
      x += dx
      if (i + 1).multiple_of?( n )
        x = 0.0
        y += dy
      end
      table.save
    end
  end
  def arrange_tables_in_columns_of(n)
    return unless n.present?
    n = n.to_i
    return unless n > 0
    dx = width / (tables.size.to_f/n).ceil
    dy = height / n
    x = 0.0
    y = 0.0
    tables.sort_by(&:number).each.with_index do |table, i|
      table.position_x = x + (dx/2) - (table_width/2)
      table.position_y = y + (dy/2) - (table_height/2)
      y += dy
      if (i + 1).multiple_of?( n )
        y = 0.0
        x += dx
      end
      table.save
    end
  end

  # Method returning the sections table width
  def table_width
    2.0
  end

  # Method returning the sections table height
  def table_height
    2.0
  end
end