ruby:按过滤器统计库存

filter_by_items.rb

def filter_meta(filter)
  { name: filter.name, num: 0, children: {}, item_ids: filter.item_ids}
end
def filter_tree(filter, node, filters) # 构建层级
  key = filter._id.to_s
  unless node.has_key?(key)
    node[key] = filter_meta(filter)
    if filter.child_ids.count > 0
      children = node[key][:children] = {}
      filters.also_in(_id: filter.child_ids).each do |child|
        filter_tree(child, children, filters)
      end
    end
  end
end
def filter_by_ids(node, item) # 商家编码过滤
  if node[:item_ids].include?(item.num_iid)
    process_filtered(node, item)
  end
end
def process_filtered(node, item)
  quantity_sum(node, item)
  if node.has_key?(:children)
    filter_by(node[:children], item)
  end
end
def filter_by(node, item)   # 过滤列表
  node.each do |key, val|
    filter_by_ids(val, item) 
  end
end
def quantity_sum(node, item) # 累加库存
  if item.skus.empty?
    node[:num] += item.num
  else
    item.skus.each do |sku|
      node[:num] += sku.quantity
    end
  end
end
def parse_tree(filters, divide='') # 展开层级
  filters.each do |key, filter|
    puts divide + "#{filter[:name]} 的库存：#{filter[:num]}"
    unless filter[:children].empty?
      parse_filter_tree(filter[:children], '  ')
    end
  end
end
user=User.all[5]
parents = user.filter_lists.where(parent_ids: []).excludes(item_ids: []) # 不支持，按价格、折扣区间过滤
child = user.filter_lists.excludes(parent_ids: [], item_ids: []) # 非顶级
items = user.items.where(approve_status: 'onsale') # 在售
result = {} # 结果集
parents.each do |parent|
  filter_tree(parent, result, child)
end
items.each do |item|
  filter_by(result, item)
end
parse_tree(result)