class Bundler::RubygemsIntegration

def self.provides?(req_str)
  Gem::Requirement.new(req_str).satisfied_by?(version)
end

def self.version
  @version ||= Gem::Version.new(Gem::VERSION)
end

def backport_base_dir
  redefine_method(Gem::Specification, :base_dir) do
    return Gem.dir unless loaded_from
    File.dirname File.dirname loaded_from
  end
end

def backport_cache_file
  redefine_method(Gem::Specification, :cache_dir) do
    @cache_dir ||= File.join base_dir, "cache"
  end
  redefine_method(Gem::Specification, :cache_file) do
    @cache_file ||= File.join cache_dir, "#{full_name}.gem"
  end
end

def backport_segment_generation
  redefine_method(Gem::Version, :segments) do
    @segments ||= @version.scan(/[0-9]+|[a-z]+/i).map do |s|
      /^\d+$/ =~ s ? s.to_i : s
    end
  end
end

def backport_spec_file
  redefine_method(Gem::Specification, :spec_dir) do
    @spec_dir ||= File.join base_dir, "specifications"
  end
  redefine_method(Gem::Specification, :spec_file) do
    @spec_file ||= File.join spec_dir, "#{full_name}.gemspec"
  end
end

def backport_yaml_initialize
  redefine_method(Gem::Version, :yaml_initialize) do |tag, map|
    @version = map['version']
    @segments = nil
    @hash = nil
  end
end

def bin_path(gem, bin, ver)
  Gem.bin_path(gem, bin, ver)
end

def build(spec, skip_validation = false)
  require 'rubygems/builder'
  Gem::Builder.new(spec).build
end

def build_args
  Gem::Command.build_args
end

def build_args=(args)
  Gem::Command.build_args = args
end

def build_gem(gem_dir, spec)
   build(spec)
end

def clear_paths
  Gem.clear_paths
end

def config_map
  Gem::ConfigMap
end

def configuration
  Gem.configuration
rescue Gem::SystemExitException => e
  Bundler.ui.error "#{e.class}: #{e.message}"
  Bundler.ui.trace e
  raise Gem::SystemExitException
end

def download_gem(spec, uri, path)
  uri = Bundler::Source.mirror_for(uri)
  fetcher = Gem::RemoteFetcher.new(configuration[:http_proxy])
  fetcher.download(spec, uri, path)
end

def ext_lock
  @ext_lock ||= Monitor.new
end

def fetch_all_remote_specs
  # Fetch all specs, minus prerelease specs
  spec_list = fetch_specs(true, false)
  # Then fetch the prerelease specs
  fetch_prerelease_specs.each {|k, v| spec_list[k] += v }
  return spec_list
end

def fetch_prerelease_specs
  fetch_specs(false, true)
rescue Gem::RemoteFetcher::FetchError
  [] # if we can't download them, there aren't any
end

def fetch_specs(all, pre, &blk)
  specs = Gem::SpecFetcher.new.list(all, pre)
  specs.each { yield } if block_given?
  specs
end

def gem_bindir
  Gem.bindir
end

def gem_cache
  gem_path.map{|p| File.expand_path("cache", p) }
end

def gem_dir
  Gem.dir
end

def gem_from_path(path, policy = nil)
  require 'rubygems/format'
  Gem::Format.from_file_by_path(path, policy)
end

def gem_path
  Gem.path
end

def inflate(obj)
  Gem.inflate(obj)
end

def loaded_specs(name)
  Gem.loaded_specs[name]
end

def mark_loaded(spec)
  Gem.loaded_specs[spec.name] = spec
end

def marshal_spec_dir
  Gem::MARSHAL_SPEC_DIR
end

def path(obj)
  obj.to_s
end

def platforms
  Gem.platforms
end

def preserve_paths
  # this is a no-op outside of Rubygems 1.8
  yield
end

def provides?(req_str)
  self.class.provides?(req_str)
end

def read_binary(path)
  Gem.read_binary(path)
end

def redefine_method(klass, method, &block)
  if klass.instance_methods(false).include?(method)
    klass.send(:remove_method, method)
  end
  klass.send(:define_method, method, &block)
end

def replace_bin_path(specs)
  gem_class = (class << Gem ; self ; end)
  redefine_method(gem_class, :bin_path) do |name, *args|
    exec_name = args.first
    if exec_name == 'bundle'
      return ENV['BUNDLE_BIN_PATH']
    end
    spec = nil
    if exec_name
      spec = specs.find { |s| s.executables.include?(exec_name) }
      spec or raise Gem::Exception, "can't find executable #{exec_name}"
      unless spec.name == name
        warn "Bundler is using a binstub that was created for a different gem.\n" \
          "This is deprecated, in future versions you may need to `bundle binstub #{name}` " \
          "to work around a system/bundle conflict."
      end
    else
      spec = specs.find  { |s| s.name == name }
      exec_name = spec.default_executable or raise Gem::Exception, "no default executable for #{spec.full_name}"
    end
    gem_bin = File.join(spec.full_gem_path, spec.bindir, exec_name)
    gem_from_path_bin = File.join(File.dirname(spec.loaded_from), spec.bindir, exec_name)
    File.exist?(gem_bin) ? gem_bin : gem_from_path_bin
  end
end

def replace_entrypoints(specs)
  replace_gem(specs)
  stub_rubygems(specs)
  replace_bin_path(specs)
  replace_refresh
  Gem.clear_paths
end

def replace_gem(specs)
  reverse_rubygems_kernel_mixin
  executables = specs.map { |s| s.executables }.flatten
  ::Kernel.send(:define_method, :gem) do |dep, *reqs|
    if executables.include? File.basename(caller.first.split(':').first)
      return
    end
    reqs.pop if reqs.last.is_a?(Hash)
    unless dep.respond_to?(:name) && dep.respond_to?(:requirement)
      dep = Gem::Dependency.new(dep, reqs)
    end
    spec = specs.find  { |s| s.name == dep.name }
    if spec.nil?
      e = Gem::LoadError.new "#{dep.name} is not part of the bundle. Add it to Gemfile."
      e.name = dep.name
      if e.respond_to?(:requirement=)
        e.requirement = dep.requirement
      else
        e.version_requirement = dep.requirement
      end
      raise e
    elsif dep !~ spec
      e = Gem::LoadError.new "can't activate #{dep}, already activated #{spec.full_name}. " \
                             "Make sure all dependencies are added to Gemfile."
      e.name = dep.name
      if e.respond_to?(:requirement=)
        e.requirement = dep.requirement
      else
        e.version_requirement = dep.requirement
      end
      raise e
    end
    true
  end
end

def replace_refresh
  gem_class = (class << Gem ; self ; end)
  redefine_method(gem_class, :refresh) { }
end

def repository_subdirectories
  %w[cache doc gems specifications]
end

def reverse_rubygems_kernel_mixin
  # Disable rubygems' gem activation system
  ::Kernel.class_eval do
    if private_method_defined?(:gem_original_require)
      alias rubygems_require require
      alias require gem_original_require
    end
    undef gem
  end
end

def ruby_engine
  Gem.ruby_engine
end

def security_policies
  @security_policies ||= begin
    require 'rubygems/security'
    Gem::Security::Policies
  rescue LoadError, NameError
    {}
  end
end

def security_policy_keys
  %w{High Medium Low AlmostNo No}.map { |level| "#{level}Security" }
end

def sources
  Gem.sources
end

def sources=(val)
  # Gem.configuration creates a new Gem::ConfigFile, which by default will read ~/.gemrc
  # If that file exists, its settings (including sources) will overwrite the values we
  # are about to set here. In order to avoid that, we force memoizing the config file now.
  configuration
  Gem.sources = val
end

def spec_cache_dirs
  @spec_cache_dirs ||= begin
    dirs = gem_path.map {|dir| File.join(dir, 'specifications')}
    dirs << Gem.spec_cache_dir if Gem.respond_to?(:spec_cache_dir) # Not in Rubygems 2.0.3 or earlier
    dirs.uniq.select {|dir| File.directory? dir}
  end
end

def spec_from_gem(path, policy = nil)
  require 'rubygems/security'
  gem_from_path(path, security_policies[policy]).spec
rescue Gem::Package::FormatError
  raise GemspecError, "Could not read gem at #{path}. It may be corrupted."
rescue Exception, Gem::Exception, Gem::Security::Exception => e
  if e.is_a?(Gem::Security::Exception) ||
      e.message =~ /unknown trust policy|unsigned gem/i ||
      e.message =~ /couldn't verify (meta)?data signature/i
    raise SecurityError,
      "The gem #{File.basename(path, '.gem')} can't be installed because " \
      "the security policy didn't allow it, with the message: #{e.message}"
  else
    raise e
  end
end

def stub_source_index(specs)
  Gem::SourceIndex.send(:alias_method, :old_initialize, :initialize)
  redefine_method(Gem::SourceIndex, :initialize) do |*args|
    @gems = {}
    # You're looking at this thinking: Oh! This is how I make those
    # rubygems deprecations go away!
    #
    # You'd be correct BUT using of this method in production code
    # must be approved by the rubygems team itself!
    #
    # This is your warning. If you use this and don't have approval
    # we can't protect you.
    #
    Deprecate.skip_during do
      self.spec_dirs = *args
      add_specs(*specs)
    end
  end
end

def ui=(obj)
  Gem::DefaultUserInteraction.ui = obj
end

def user_home
  Gem.user_home
end

def version
  self.class.version
end

def with_build_args(args)
  ext_lock.synchronize do
    old_args = self.build_args
    begin
      self.build_args = args
      yield
    ensure
      self.build_args = old_args
    end
  end
end