configure

#!/usr/bin/env ruby

require 'rbconfig'

begin
  require 'psych'
rescue LoadError
ensure
  require 'yaml'
end

root = File.expand_path File.dirname(__FILE__)

# pull in helper libs
Dir.glob(File.join(root, 'lib', '*.rb')).each do |f|
  require f
end


class Configure

  BUILD_CONFIG = { :VERSION => '0.2.0', :APPNAME => 'xval' }

  def initialize(root)
    @config = File.join(root, 'config.yaml')
    @config_h = File.join(root, 'config.h')

    @defines = [ 'HAVE_CONFIG_H' ]

    # TODO add /usr/local/lib and /usr/local/include?
    @include_dirs = [
      'C:/devlibs/libxml2/include/libxml2',
      'C:/devlibs/lua52/include'
    ]
    @library_dirs = [
      'C:/devlibs/libxml2/lib',
      'C:/devlibs/lua52/lib'
    ]

    @opts = Trollop.options do
      banner <<-EOT
usage: ruby configure [options]

libxml2 options:
EOT
      opt :with_xml2_include, 'libxml2 header directory', :type => :string, :short => :none
      opt :with_xml2_lib, 'libxml2 library directory', :type => :string, :short => :none

      banner <<-EOT

liblua options:
EOT
      opt :with_lua_include, 'liblua header directory', :type => :string, :short => :none
      opt :with_lua_lib, 'liblua library directory', :type => :string, :short => :none
      opt :lua_libname, 'libname sans prefix', :short => :none, :default => 'lua52'

      banner <<-EOT

compiler toolkit options:
EOT
      opt :cc, 'C compiler', :short => :none, :default => 'gcc'
      opt :defines, 'preprocessor definitions', :type => :strings, :short => :d
      opt :optflags, 'optimization settings', :type => :strings, :short => :o, :default => ['O3']
      opt :debugflags, 'debug settings', :type => :strings, :short => :g

      banner <<-EOT

general options:
EOT
      opt :chatty_build, 'build app with verbose messages', :short => :none
    end

  end

  def process_env
    BUILD_CONFIG[:APPNAME] << '.exe' if windows?

    @cc = ENV['CC'] || 'gcc'

    cpath = normalize_path ENV['CPATH'] if ENV['CPATH']
    @include_dirs.unshift(cpath).flatten! if cpath

    lib_path = normalize_path ENV['LIBRARY_PATH'] if ENV['LIBRARY_PATH']
    @library_dirs.unshift(lib_path).flatten! if lib_path
  end

  def process_args
    @cc = @opts[:cc] if @opts[:cc_given]

    @defines << 'NDEBUG' unless @opts[:chatty_build_given]
    @defines.concat @opts[:defines] if @opts[:defines_given]

    { :with_xml2_include => :with_xml2_include_given,
      :with_lua_include => :with_lua_include_given }.each do |k,v|
      cpath = normalize_path @opts[k] if @opts[v]
      @include_dirs.unshift(cpath).flatten! if cpath
    end

    { :with_xml2_lib => :with_xml2_lib_given,
      :with_lua_lib => :with_lua_lib_given }.each do |k,v|
      lib_path = normalize_path @opts[k] if @opts[v]
      @library_dirs.unshift(lib_path).flatten! if lib_path
    end

  end

  def make_config
    BUILD_CONFIG[:shell] = windows? ? 'cmd.exe /c' : 'sh -c'
    BUILD_CONFIG[:cc] = @cc
    BUILD_CONFIG[:defines] = @defines unless @defines.empty?
    BUILD_CONFIG[:optflags] = @opts[:optflags] unless @opts[:optflags].empty?
    BUILD_CONFIG[:debugflags] = @opts[:debugflags] if @opts[:debugflags]
    BUILD_CONFIG[:strip_all] = '-s' unless @opts[:debugflags]

    BUILD_CONFIG[:include_dirs] = @include_dirs
    BUILD_CONFIG[:library_dirs] = @library_dirs

    BUILD_CONFIG[:libs] = windows? ?
                          "-Wl,-static -lxml2 -l#{@opts[:lua_libname]} -Wl,-dy,--as-needed -lws2_32" :
                          "-Wl,-static -lxml2 -l#{@opts[:lua_libname]} -Wl,-dy,--as-needed -ldl -lc -lm -lz"
  end

  def write_config
    File.open(@config, 'wb') do |f|
      f.puts BUILD_CONFIG.to_yaml
    end

    File.open(@config_h, 'wb') do |f|
      version_triple = BUILD_CONFIG[:VERSION].split(/\./)

      f.puts <<-EOT
/* config.h.  Generated from configure.  */

#define XVALID_VERSION_MAJOR   #{version_triple[0]}
#define XVALID_VERSION_MINOR   #{version_triple[1]}
#define XVALID_VERSION_PATCH   #{version_triple[2]}
#define XVALID_VERSION_STRING  "#{BUILD_CONFIG[:VERSION]}"
EOT

      f.puts '#define XVALID_CHATTY_BUILD    1' if @opts[:chatty_build]
    end
  end

  def call
    process_env
    process_args
    make_config
    write_config
  end

private
  def normalize_path(path)
    dir_sep = windows? ? /;/ : /:/
    path.gsub('\\', File::SEPARATOR).split(dir_sep)
  end

  def windows?
    @windows ||= RbConfig::CONFIG['host_os'] =~ /(mingw|mswin)/
  end

end

Configure.new(root).call