# frozen_string_literal: true

require "i18n/tasks/data/tree/traversal"
module I18n::Tasks::Data::Tree
  # A list of nodes
  class Nodes
    include Enumerable
    include Traversal

    attr_reader :list

    def initialize(opts = {})
      @list = opts[:nodes] ? opts[:nodes].to_a.clone : []
    end

    delegate :each, :present?, :empty?, :blank?, :size, :to_a, to: :@list

    def to_nodes
      self
    end

    def attributes
      {nodes: @list}
    end

    def derive(new_attr = {})
      attr = attributes.except(:nodes, :parent).merge(new_attr)
      node_attr = new_attr.slice(:parent)
      attr[:nodes] ||= @list.map { |node| node.derive(node_attr) }
      self.class.new(attr)
    end

    def to_hash(sort = false)
      (@hash ||= {})[sort] ||= if sort
        sort_by(&:key)
      else
        self
      end.map { |node| node.to_hash(sort) }.reduce({}, :deep_merge!)
    end

    delegate :to_json, to: :to_hash
    delegate :to_yaml, to: :to_hash

    def inspect
      if present?
        map(&:inspect) * "\n"
      else
        Rainbow("{∅}").faint
      end
    end

    # methods below change state

    def remove!(node)
      @list.delete(node) || fail("#{node.full_key} not found in #{inspect}")
      dirty!
      self
    end

    def append!(other)
      @list += other.to_a
      dirty!
      self
    end

    def append(other)
      derive.append!(other)
    end

    alias_method :<<, :append

    def merge!(nodes)
      @list += nodes.to_a
      dirty!
      self
    end
    alias_method :+, :merge!

    def children(&block)
      return to_enum(:children) { map { |c| c.children ? c.children.size : 0 }.reduce(:+) } unless block

      each do |node|
        node.children.each(&block) if node.children?
      end
    end

    alias_method :children?, :any?

    protected

    def dirty!
      @hash = nil
    end
  end
end
