class Yalphabetize::Aliaser

# File lib/yalphabetize/aliaser.rb, line 5
def initialize(stream_node)
  @stream_node = stream_node
  @aliases = {}
end

# File lib/yalphabetize/aliaser.rb, line 10
def call
  nodes.each do |node|
    next unless node.respond_to?(:anchor) && node.anchor

    ensure_anchor_then_alias(node)
  end
  stream_node
end

# File lib/yalphabetize/aliaser.rb, line 45
def convert_node(child_node, anchor_node, alias_node)
  if child_node == anchor_node
    alias_node
  elsif child_node == alias_node
    anchor_node
  else
    child_node
  end
end

# File lib/yalphabetize/aliaser.rb, line 23
def ensure_anchor_then_alias(node)
  if node.alias?
    aliases[node.anchor] ||= node
  elsif aliases[node.anchor]
    swap(node, aliases[node.anchor])
  end
end

# File lib/yalphabetize/aliaser.rb, line 39
def nodes
  stream_node.select do |node|
    node.respond_to?(:anchor) && node.anchor
  end
end

# File lib/yalphabetize/aliaser.rb, line 31
def swap(anchor_node, alias_node)
  stream_node.each do |node|
    node.children&.map! do |child_node|
      convert_node(child_node, anchor_node, alias_node)
    end
  end
end