### Monkeypatch to work around the broken Rakefile generated by Mkrf <= 0.2.3

# This fixes:

# * Some weird unnecessary string interpolation

# * The :install task doesn't work unless you have RUBYARCHDIR in your environment, instead of

#   falling back to CONFIG['sitearchdir'].

# * The :install task created the target install directory every time instead of just

#   declaring a dependency on a directory task

require 'mkrf/generator'

RAKEFILE_TEMPLATE = %q{

	# Generated by monkeypatched mkrf

	require 'rake/clean'

	require 'rbconfig'

	include Config

	SRC = FileList[#{sources.join(',')}]

	OBJ = SRC.ext('#{objext}')

	CC = '#{@cc}'

	ADDITIONAL_OBJECTS = '#{objects}'

	LDSHARED = "#{@available.ldshared_string} #{ldshared}"

	LIBPATH =  "#{library_path(CONFIG['libdir'])} #{@available.library_paths_compile_string}"

	INCLUDES = "#{@available.includes_compile_string}"

	LIBS = "#{@available.library_compile_string}"

	CFLAGS = "#{cflags} #{defines_compile_string}"

	RUBYARCHDIR = ENV["RUBYARCHDIR"] || CONFIG['sitearchdir']

	LIBRUBYARG_SHARED = "#{CONFIG['LIBRUBYARG_SHARED']}"

	EXT = '#{@extension_name}'

	CLEAN.include( EXT, '*.#{objext}' )

	CLOBBER.include( 'mkrf.log' )

	task :default => EXT

	rule '.#{objext}' => '.#{@source_extension}' do |t|

	end

	desc "Build this extension"

	file EXT => OBJ do

	end

	directory RUBYARCHDIR

	desc "Install this extension"

	task :install => [EXT, RUBYARCHDIR] do

	end

	#{additional_code}

}.gsub( /^\t/m, '' )

module Mkrf

	class Availability

		# Create a new Availability instance.

		#

		# Valid keys for the options hash include:

		# * <tt>:loaded_libs</tt> -- libraries to load by default

		# * <tt>:library_paths</tt> -- libraries paths to include by default

		# * <tt>:headers</tt> -- headers to load by default

		# * <tt>:compiler</tt> -- which compiler to use when determining availability

		# * <tt>:includes</tt> -- directories that should be searched for include files

		def initialize(options = {})      

			@loaded_libs = options[:loaded_libs] || []

			@loaded_libs.flatten!

			@library_paths = [(options[:library_paths] || [])].flatten

			# Not sure what COMMON_HEADERS looks like when populated

			@headers = options[:headers] || [] # Config::CONFIG["COMMON_HEADERS"]

			@compiler = options[:compiler] || Config::CONFIG["CC"]

			@includes = [(options[:includes] || DEFAULT_INCLUDES)].flatten

			@logger = Logger.new('mkrf.log')

			@defines = []

		end

		def can_link?( function_body )

			silence_command_line do

				create_source(function_body)

				cmd = link_command()

				@logger.debug "Running link command: #{cmd}"

				system( cmd )

			end

		ensure

			FileUtils.rm_f TEMP_SOURCE_FILE

			FileUtils.rm_f TEMP_EXECUTABLE

		end

		# Add the LIBRUBYARG_SHARED setting to the library paths for non-windows boxen. This is

		# necessary if Ruby is installed in a directory that isn't in the default library

		# search path (e.g., on FreeBSD where Ruby is /usr/local/bin/ruby).

		def library_paths_compile_string

			if RUBY_PLATFORM =~ /mswin/

				@library_paths.collect {|l| "/libpath:#{l}"}.join(' ')

			else

				Config::CONFIG['LIBRUBYARG_SHARED'] + @library_paths.collect {|l| "-L#{l}"}.join(' ')

			end

		end

		# Separate includes with a newline instead of a literal '\n'

		def header_include_string

			@headers.collect {|header| "#include <#{header}>"}.join( "\n" )

		end

		# Log the created source to the logfile

		def create_source( src )

			@logger.debug "Creating source file:\n#{src}"

			File.open( TEMP_SOURCE_FILE, "w+" ) do |f|

				f.write( src )

			end

		end

		# Prepend the LIBS string directly to the @loaded_libs, as not all arguments in

		# it 

		def library_compile_string

			added_libs = nil

			if RUBY_PLATFORM =~ /mswin/

				added_libs = @loaded_libs.join(' ')

			else

				added_libs = @loaded_libs.collect {|l| "-l#{l}"}.join(' ')

			end

			return Config::CONFIG["LIBS"] + ' ' + added_libs

		end

		# Redirect to the mkrf log instead of /dev/null

		def silence_stream( stream )

			old_stream = stream.dup

			stream.reopen( @logger.instance_variable_get(:@logdev).dev )

			stream.sync = true

			yield

		ensure

			stream.reopen( old_stream )

		end

	end

	class Generator

		def rakefile_contents # :nodoc:

			objext = CONFIG['OBJEXT']

			return interpolate( RAKEFILE_TEMPLATE, binding() )

		end

		### Interpolate any '#{...}' placeholders in the string within the given

		### +scope+ (a Binding object).

	    def interpolate( string, scope )

	        unless scope.is_a?( Binding )

	            raise TypeError, "Argument to interpolate must be a Binding, not "\

	                "a #{scope.class.name}"

	        end

			# $stderr.puts ">>> Interpolating '#{self}'..."

	        copy = string.gsub( /"/, %q:\": )

	        eval( '"' + copy + '"', scope )

		rescue Exception => err

			nicetrace = err.backtrace.find_all {|frame|

				/in `(interpolate|eval)'/i !~ frame

			}

			Kernel.raise( err, err.message, nicetrace )

	    end

	end # class Generator

end # module Mkrf