module Opal::BuilderScheduler::Prefork::OrderCorrector

def build_require_order_array(requires, requires_hash, built_for = Set.new)
  array = []
  requires.each do |name|
    next if built_for.include?(name)
    built_for << name
    asset_requires = requires_hash[name]
    array += build_require_order_array(asset_requires, requires_hash, built_for) if asset_requires
    array << name
  end
  array
end

def correct_order(processed, requires, builder)
  # Let's build a hash that maps a filename to an array of files it requires
  requires_hash = processed.to_h do |i|
    [i.filename, expand_requires(i.requires, builder)]
  end
  # Let's build an array with a correct order of requires
  order_array = build_require_order_array(expand_requires(requires, builder), requires_hash)
  # If a key is duplicated, remove the last duplicate
  order_array = order_array.uniq
  # Create a hash from this array: [a,b,c] => [a => 0, b => 1, c => 2]
  order_hash = order_array.each_with_index.to_h
  # Let's return a processed array that has elements in the order provided
  processed.sort_by do |asset|
    # If a filename isn't present somehow in our hash, let's put it at the end
    order_hash[asset.filename] || order_array.length
  end
end

def expand_requires(requires, builder)
  requires.map { |i| builder.expand_ext(i) }
end