# encoding: utf-8

require 'yaml'

Gem::Specification.new do |gemspec|
  root    = File.dirname(__FILE__)
  lib_dir = File.join(root,'lib')
  files   = `git ls-files`.split($/)

  filter_files = lambda { |paths|
    files & case paths
            when Array
              paths
            when String
              Dir[paths]
            end
  }

  version = {
    :file     => 'nokogiri/diff/version',
    :constant => 'Nokogiri::Diff::VERSION'
  }

  defaults = {
    'name'            => File.basename(root),
    'files'           => files,
    'require_paths'   => ['ext', 'lib'].select { |dir| File.directory?(dir) },
    'executables'     => filter_files['bin/*'].map { |path| File.basename(path) },
    'test_files'      => filter_files['{test/{**/}*_test.rb,spec/{**/}*_spec.rb}'],
    'doc_files'       => filter_files['*.{txt,rdoc,md,markdown,tt,textile}'],
    'extra_doc_files' => filter_files['*.{txt,rdoc,md,markdown,tt,textile}']
  }

  metadata = defaults.merge(YAML.load_file('gemspec.yml'))

  gemspec.name    = metadata['name']
  gemspec.version = if metadata['version']
                      metadata['version']
                    else
                      $LOAD_PATH << lib_dir unless $LOAD_PATH.include?(lib_dir)

                      require version[:file]
                      eval(version[:constant])
                    end

  gemspec.summary     = metadata.fetch('summary',metadata['description'])
  gemspec.description = metadata.fetch('description',metadata['summary'])

  gemspec.licenses = Array(metadata['license'])
  gemspec.authors  = Array(metadata['authors'])

  gemspec.email    = metadata['email']
  gemspec.homepage = metadata['homepage']

  gemspec.require_paths = Array(metadata['require_paths'])
  gemspec.files         = filter_files[metadata['files']]
  gemspec.executables   = metadata['executables']
  gemspec.extensions    = metadata['extensions']

  if Gem::VERSION < '1.7.'
    gemspec.default_executable = gemspec.executables.first
  end

  gemspec.test_files       = filter_files[metadata['test_files']]
  gemspec.extra_rdoc_files = Array(metadata['extra_doc_files'])

  gemspec.post_install_message = metadata['post_install_message']
  gemspec.requirements         = metadata['requirements']

  if gemspec.respond_to?(:required_ruby_version=)
    gemspec.required_ruby_version = metadata['required_ruby_version']
  end

  if gemspec.respond_to?(:required_rubygems_version=)
    gemspec.required_rubygems_version = metadata['required_ruby_version']
  end

  parse_versions = lambda { |versions|
    case versions
    when Array
      versions.map { |v| v.to_s }
    when String
      versions.split(/,\s*/)
    end
  }

  if metadata['dependencies']
    metadata['dependencies'].each do |name,versions|
      gemspec.add_dependency(name,parse_versions[versions])  
    end
  end

  if metadata['runtime_dependencies']
    metadata['runtime_dependencies'].each do |name,versions|
      gemspec.add_runtime_dependency(name,parse_versions[versions])  
    end
  end

  if metadata['development_dependencies']
    metadata['development_dependencies'].each do |name,versions|
      gemspec.add_development_dependency(name,parse_versions[versions])  
    end
  end
end