class Bundler::SpecSet

def [](key)
  key = key.name if key.respond_to?(:name)
  lookup[key].reverse
end

def []=(key, value)
  @specs << value
  @lookup = nil
  @sorted = nil
  value
end

def extract_circular_gems(error)
  if Bundler.current_ruby.mri? && Bundler.current_ruby.on_19?
    error.message.scan(/(\w+) \([^)]/).flatten
  else
    error.message.scan(/@name="(.*?)"/).flatten
  end
end

def for(dependencies, skip = [], check = false, match_current_platform = false)
  handled, deps, specs = {}, dependencies.dup, []
  skip << 'bundler'
  until deps.empty?
    dep = deps.shift
    next if handled[dep] || skip.include?(dep.name)
    spec = lookup[dep.name].find do |s|
      if match_current_platform
        Gem::Platform.match(s.platform)
      else
        s.match_platform(dep.__platform)
      end
    end
    handled[dep] = true
    if spec
      specs << spec
      spec.dependencies.each do |d|
        next if d.type == :development
        d = DepProxy.new(d, dep.__platform) unless match_current_platform
        deps << d
      end
    elsif check
      return false
    end
  end
  if spec = lookup['bundler'].first
    specs << spec
  end
  check ? true : SpecSet.new(specs)
end

def initialize(specs)
  @specs = specs.sort_by { |s| s.name }
end

def lookup
  @lookup ||= begin
    lookup = Hash.new { |h,k| h[k] = [] }
    specs = @specs.sort_by do |s|
      s.platform.to_s == 'ruby' ? "\0" : s.platform.to_s
    end
    specs.reverse_each do |s|
      lookup[s.name] << s
    end
    lookup
  end
end

def materialize(deps, missing_specs = nil)
  materialized = self.for(deps, [], false, true).to_a
  deps = materialized.map {|s| s.name }.uniq
  materialized.map! do |s|
    next s unless s.is_a?(LazySpecification)
    s.source.dependency_names = deps if s.source.respond_to?(:dependency_names=)
    spec = s.__materialize__
    if missing_specs
      missing_specs << s unless spec
    else
      raise GemNotFound, "Could not find #{s.full_name} in any of the sources" unless spec
    end
    spec if spec
  end
  SpecSet.new(materialized.compact)
end

def merge(set)
  arr = sorted.dup
  set.each do |s|
    next if arr.any? { |s2| s2.name == s.name && s2.version == s.version && s2.platform == s.platform }
    arr << s
  end
  SpecSet.new(arr)
end

def sort!
  self
end

def sorted
  rake = @specs.find { |s| s.name == 'rake' }
  begin
    @sorted ||= ([rake] + tsort).compact.uniq
  rescue TSort::Cyclic => error
    cgems = extract_circular_gems(error)
    raise CyclicDependencyError, "Your Gemfile requires gems that depend" \
      " depend on each other, creating an infinite loop. Please remove" \
      " either gem '#{cgems[1]}' or gem '#{cgems[0]}' and try again."
  end
end

def to_a
  sorted.dup
end

def to_hash
  lookup.dup
end

def tsort_each_child(s)
  s.dependencies.sort_by { |d| d.name }.each do |d|
    next if d.type == :development
    lookup[d.name].each { |s2| yield s2 }
  end
end

def tsort_each_node
  @specs.each { |s| yield s }
end

def valid_for?(deps)
  self.for(deps, [], true)
end