# -*- mode: ruby; coding: utf-8 -*-


require 'rbconfig'


task :ext => 'ext:build'

%w[clean].each do |t|
  task t.intern => "ext:#{t}"
end


namespace :ext do


  rbconf = RbConfig::CONFIG

  mod      = MODULE
  modname  = env :MODNAME,  mod.name.downcase
  dlname   = env :DLNAME,   'native'
  dlext    = env :DLEXT,    rbconf['DLEXT'] || 'so'
  extdir   = env :EXTDIR,   "ext/#{modname}"
  libdir   = env :LIBDIR,   "lib/#{modname}"
  ruby     = env :RUBY,     'ruby'
  make     = env :MAKE,     'make'
  cxx      = env :CXX,      rbconf['CXX'] || 'g++'
  defs     = env :DEFS,     []
  debug    = env :DEBUG,    false
  incdirs  = env :INCDIRS,  []
  cxxflags = env(:CXXFLAGS, rbconf['CXXFLAGS']).dup

  outname = "#{dlname}.#{dlext}"
  extout  = File.join extdir, outname
  libout  = File.join libdir, outname

  srcs = FileList["#{extdir}/**/*.cpp"]

  incroot = rbconf['rubyhdrdir']
  incdirs += [
    incroot,
    "#{incroot}/#{RUBY_PLATFORM}",
    '/opt/local/include',
    '/opt/include'
  ]
  incdirs.uniq!

  defs     << '_DEBUG' if debug
  defs     << 'NDEBUG' unless debug
  defs     << 'WIN32' if win32?
  defs     << 'COCOA' if cocoa?
  defs     << $~[0].upcase if RUBY_PLATFORM =~ /mswin|ming|cygwin|darwin/i
  cxxflags << ' ' << rbconf['debugflags'] if debug
  cxxflags << ' --stdlib=libc++' if clang?
  cxxflags << defs.map{|s| " -D#{s}"}.join
  cxxflags << incdirs.map{|s| " -I#{s}"}.join

  extconf  = File.join extdir, 'extconf.rb'
  makefile = File.join extdir, 'Makefile'
  depend   = File.join extdir, 'depend.mf'


  task :build => libout

  task :clean do
    sh %( cd #{extdir} && #{make} clean ) if File.exist? makefile
    sh %( rm -rf #{makefile} #{depend} #{libout} )
  end

  file libout => extout do
    sh %( cp #{extout} #{libout} )
  end

  file extout => [:lib, makefile] do
    sh %( cd #{extdir} && #{make} )
  end

  file makefile => [extconf, depend] do
    sh %( cd #{extdir} && #{ruby} #{File.basename extconf} )
  end

  file depend => srcs do
    inc = incdirs.map{|s| " -I#{s}"}.join
    src = srcs.map{|cpp| File.basename cpp}.join ' '
    dep = File.basename depend
    sh %( cd #{extdir} && #{cxx} -M #{cxxflags} #{inc} #{src} > #{dep} )
  end


end# :ext