#!/usr/bin/env ruby

###
### inline-require - expand 'require "foo"' into inline code
###
### usage: inline-require [-h] [-I path[,path2,..]] script
###
### copyright(c) 2006-2011 kuwata-lab.com all rights reserved.
### 2.7.0
### $Rev: 10 $
###


class InlineRequire

   def initialize(opts={})
      @opts = opts.dup
   end
   attr_accessor :opts

   def expand(filename)
      sbuf = ''
      inlined = []
      level = 0
      expand_require(filename, sbuf, inlined, level)
      return sbuf
   end

   private

   def expand_require(filename, sbuf, inlined, level)
      raise "*** assertion error" if inlined.include?(filename)
      remove_comment  = @opts[:remove_comment]
      expand_indented = @opts[:expand_indented]
      keep_filename   = @opts[:keep_filename]
      loaded_features = @opts[:loaded_features]
      inlined << filename
      prog = File.read(filename)
      n = 0
      flag_if_file = false
      prog.each_line do |line|
         n += 1

         ## comment out from 'if __FILE__ == $0' to 'end'
         if level > 0
            if flag_if_file
               sbuf << "#" << line
               flag_if_file = false if line =~ /^end$/
               next
            end
            if line =~ /^if\s+__FILE__\s*==\s*\$0(\s+then)?$/ || line =~ /^if\s+\$0\s*==\s*__FILE__(\s+then)?$/
               flag_if_file = true
               sbuf << "#" << line
               next
            end
         end

         ## find 'require "foo"' and expand it to inline code
         flag_inline = false
         pattern = expand_indented ? /^[ \t]*require ['"](.*)["']\s*$/ \
                                   :       /^require ['"](.*)["']\s*$/
         if line =~ pattern
            libname = $1
            libpath = find_library(libname)
            $stderr.puts "*** debug: libpath=#{libpath.inspect}" if $debug_mode
            unless libpath
               #raise "file '#{filename}'(line #{n}): library '#{libname}' not found."
               warn "file '#{filename}'(line #{n}): library '#{libname}' not found."
            else
              flag_inline = true if libpath =~ /\.rb$/ && local_library?(libpath)
            end
         end
         if !flag_inline
            sbuf << line   unless remove_comment && line =~ /^[ \t]*\#/
         elsif inlined.include?(libpath)
            sbuf << "#--already included #{line}"     unless remove_comment
         else
            if keep_filename
               @n ||= 0;  @n += 1;  n = @n
            end
            sbuf << "#--begin of #{line}"             unless remove_comment
            sbuf << "$LOADED_FEATURES << '#{libname}.rb'\n" if loaded_features
            sbuf << "eval <<'END_OF_SCRIPT__#{n}', TOPLEVEL_BINDING, '#{libpath}', 1\n" if keep_filename
            expand_require(libpath, sbuf, inlined, level+1)
            sbuf << "END_OF_SCRIPT__#{n}\n"               if keep_filename
            sbuf << "#--end of #{line}"               unless remove_comment
         end
      end
      #sbuf << "\n" if sbuf[-1] != ?\n
   end

   def local_library?(libpath)
      return libpath !~ /^\//
   end

   def find_library(libname)
      if libname =~ /^\.rb$/
         libname_rb = libname
         libname_so = nil
      elsif libname =~ /^\.so$/
         libname_rb = nil
         libname_so = libname
      else
         libname_rb = libname + ".rb"
         libname_so = libname + ".so"
      end
      $LOAD_PATH.each do |path|
         if libname_rb
            libpath = path + "/" + libname_rb
            return libpath if test(?f, libpath)
         end
         if libname_so
            libpath = path + "/" + libname_so
            return libpath if test(?f, libpath)
         end
      end
      return nil
   end

end

if __FILE__ == $0

   begin
      require "optparse"
      op = OptionParser.new
      options = {}
      op.on("-h", "--help") {|v| options[:help] = v }
      op.on("-I libpath")   {|v| options[:libpath] = v }
      op.on("-i")           {|v| options[:expand_indented] = v }
      op.on("-c")           {|v| options[:remove_comment] = v }
      op.on("-k")           {|v| options[:keep_filename] = v }
      op.on("-l")           {|v| options[:loaded_features] = v }
      op.on("-D")           {|v| options[:debug] = v }
      op.parse!()

      $debug_mode = options[:debug]

      if options[:help]
         command = File.basename($0)
         puts "Usage: #{command} [-h] [-I path[,path2,..]] script"
         puts "  -h                   : help"
         puts "  -i                   : expand indented require(), too"
         puts "  -c                   : remove comment lines start with '#'"
         puts "  -k                   : keep filename (for debugging)"
         puts "  -l                   : append libs to $LOADED_FEATURES"
         puts "  -I path[,path2,...]  : ruby library path"
         exit(0)
      end

      if options[:libpath]
         rubylib_paths = options[:libpath].split(/,/)
      else
         rubylib_paths = []
      end
      $stderr.puts "*** debug: rubylib_paths=#{rubylib_paths.inspect}" if $debug_mode
      $LOAD_PATH.concat(rubylib_paths)

      filenames = ARGV

      opts = { :expand_indented => options[:expand_indented],
               :remove_comment  => options[:remove_comment],
               :keep_filename   => options[:keep_filename],
               :loaded_features => options[:loaded_features] }
      inline_require = InlineRequire.new(opts)
      filenames.each do |filename|
         print inline_require.expand(filename)
      end

   rescue => ex
      if $debug_mode
         raise ex
      else
         $stderr.puts ex.message
      end

   end

end