#!/usr/bin/ruby -w

# Ruby beautifier, version 2.1, 09/11/2006
# Copyright (c) 2006, P. Lutus
# Released under the GPL

$tabSize = 2
$tabStr = " "

# indent regexp tests

$indentExp = [
   /^module\b/,
   /^if\b/,
   /(=\s*|^)until\b/,
   /(=\s*|^)for\b/,
   /^unless\b/,
   /(=\s*|^)while\b/,
   /(=\s*|^)begin\b/,
   /(^| )case\b/,
   /\bthen\b/,
   /^class\b/,
   /^rescue\b/,
   /^def\b/,
   /\bdo\b/,
   /^else\b/,
   /^elsif\b/,
   /^ensure\b/,
   /\bwhen\b/,
   /\{[^\}]*$/,
   /\[[^\]]*$/
]

# outdent regexp tests

$outdentExp = [
   /^rescue\b/,
   /^ensure\b/,
   /^elsif\b/,
   /^end\b/,
   /^else\b/,
   /\bwhen\b/,
   /^[^\{]*\}/,
   /^[^\[]*\]/
]

def makeTab(tab)
   return (tab < 0)?"":$tabStr * $tabSize * tab
end

def addLine(line,tab)
   line.strip!
   line = makeTab(tab)+line if line.length > 0
   return line + "\n"
end

def beautifyRuby(path)
   commentBlock = false
   programEnd = false
   multiLineArray = Array.new
   multiLineStr = ""
   tab = 0
   source = File.read(path)
   dest = ""
   source.split("\n").each do |line|
      if(!programEnd)
         # detect program end mark
         if(line =~ /^__END__$/)
            programEnd = true
         else
            # combine continuing lines
            if(!(line =~ /^\s*#/) && line =~ /[^\\]\\\s*$/)
               multiLineArray.push line
               multiLineStr += line.sub(/^(.*)\\\s*$/,"\\1")
               next
            end

            # add final line
            if(multiLineStr.length > 0)
               multiLineArray.push line
               multiLineStr += line.sub(/^(.*)\\\s*$/,"\\1")
            end

            tline = ((multiLineStr.length > 0)?multiLineStr:line).strip
            if(tline =~ /^=begin/)
               commentBlock = true
            end
         end
      end
      if(commentBlock || programEnd)
         # add the line unchanged
         dest += line + "\n"
      else
         commentLine = (tline =~ /^#/)
         if(!commentLine)
            # throw out sequences that will
            # only sow confusion
            while tline.gsub!(/'.*?'/,"")
            end
            while tline.gsub!(/".*?"/,"")
            end
            while tline.gsub!(/\`.*?\`/,"")
            end
            while tline.gsub!(/\{[^\{]*?\}/,"")
            end
            while tline.gsub!(/\([^\(]*?\)/,"")
            end
            while tline.gsub!(/\/.*?\//,"")
            end
            while tline.gsub!(/%r(.).*?\1/,"")
            end
            tline.gsub!(/\\\"/,"'")
            $outdentExp.each do |re|
               if(tline =~ re)
                  tab -= 1
                  break
               end
            end
         end
         if (multiLineArray.length > 0)
            multiLineArray.each do |ml|
               dest += addLine(ml,tab)
            end
            multiLineArray.clear
            multiLineStr = ""
         else
            dest += addLine(line,tab)
         end
         if(!commentLine)
            $indentExp.each do |re|
               if(tline =~ re && !(tline =~ /\s+end\s*$/))
                  tab += 1
                  break
               end
            end
         end
      end
      if(tline =~ /^=end/)
         commentBlock = false
      end
   end
   if(source != dest)
      # make a backup copy
      File.open(path + "~","w") { |f| f.write(source) }
      # overwrite the original
      File.open(path,"w") { |f| f.write(dest) }
   end
   if(tab != 0)
      STDERR.puts "#{path}: Indentation error: #{tab}"
   end
end

if(!ARGV[0])
   STDERR.puts "usage: Ruby filenames to beautify."
   exit 0
end

ARGV.each do |path|
   beautifyRuby(path)
end