#!/usr/bin/env ruby
# Copyright (C) 2005, 2006, 2007 Gregoire Lejeune <gregoire.lejeune@free.fr>
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

require 'getoptlong'
require 'graphviz'
require "graphviz/constants"
require 'rbconfig'

DEBUG = false

class Rb2Gv
  REQUIRE = /^\s*require\s*("|')([^\1]*)(\1)/

  def initialize( xGVPath )
    @oGraph = GraphViz::new( "G", :path => xGVPath )
    @oGraph['size'] = '10,10'
    @hxNodes = Hash::new( )
    @hxEdge = Hash::new( )
  end
  
  public
  def parse( xFile )
    @hxNodes[xFile] = gv_newNode( xFile )
    puts "+ Node #{xFile}" if DEBUG

    parseFile( xFile, nil, xFile )
  end

  def out( xFormat = "dot", xFile = nil )
    if xFile.nil? == true
      @oGraph.output( "output" => xFormat )
    else
      @oGraph.output( "output" => xFormat, "file" => xFile )
    end
  end
  
  private
  def gv_newNode( xNode, xShape = "box", xColor = nil )
    xNodeName = xNode.gsub( /[^a-zA-Z0-9]/, "_" )
    if xColor.nil? == true
      @oGraph.add_node( xNodeName, "label" => xNode, "shape" => xShape )
    else
      @oGraph.add_node( xNodeName, "label" => xNode, "shape" => xShape, "style" => "filled", "color" => xColor )
    end
  end
  
  def getLibraryPath( xLib, xExt = "rb" )
    xPath = [ "libexecdir", "libdir", "sitedir", "rubylibdir", "sitelibdir", "archdir", "sitedir", "sitearchdir" ]
    xRbLib = with_config( xLib+'lib', xLib)
    if /\.(rb|so)$/.match( xRbLib )
      xRbFile = xRbLib
    else
      xRbFile = xRbLib + "." + xExt
    end
    
    xPath.each do |xDir|
      xCurrentPath = Config::expand( Config::CONFIG[xDir] )
      xFileFound = File.join( xCurrentPath, xRbFile )
      if File.exist?( xFileFound )
        return xFileFound
      end
    end

    return nil
  end
  
  def parseFile( xFile, xFromFile = nil, xLib = nil )
  
    if xFromFile.nil? == false
      puts "Parse #{xFile} required in #{xFromFile} :" if DEBUG
    else
      puts "Parse #{xFile} :" if DEBUG
    end

    fp = open( xFile, 'r' )
    xData = fp.read()
    fp.close
    
    xData.each do |xLine|
      if lxLineMatch = REQUIRE.match( xLine )
        xRequiredLib = lxLineMatch[2]
        
        if @hxNodes.has_key?( xRequiredLib ) == false
          puts "  + Node #{xRequiredLib}" if DEBUG

          xRequiredFile = getLibraryPath( xRequiredLib )
          if xRequiredFile.nil? == false
            @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib )
            parseFile( xRequiredFile, xFile, xRequiredLib )
          else
            if getLibraryPath( xRequiredLib, "so" ).nil? == false
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib, "ellipse" )
            else
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib, "ellipse", "red" )
            end
          end

        end
        
        puts "  + Edge #{xLib} -> #{xRequiredLib}" if DEBUG
        @oGraph.add_edge( @hxNodes[xLib], @hxNodes[xRequiredLib] )

      end
    end
    
  end

end

def usage 
  puts "usage: ruby2gv.rb [-Tformat] [-ofile] [-h] [-V] script"
  puts "-T, --output-format format    Output format (default: PNG)"
  puts "-o, --output-file file        Output file (default: STDOUT)"
  puts "-p, --path                    Graphviz path"
  puts "-V, --version                 Show version"
  puts "-h, --help                    Show this usage message"
end

def version
  puts "Ruby2GraphViz v#{Constants::RGV_VERSION}, (c)2005 Gregoire Lejeune <gregoire.lejeune@free.fr>"
  puts ""
  puts "This program is free software; you can redistribute it and/or modify"
  puts "it under the terms of the GNU General Public License as published by"
  puts "the Free Software Foundation; either version 2 of the License, or"
  puts "(at your option) any later version."
  puts ""
  puts "This program is distributed in the hope that it will be useful,"
  puts "but WITHOUT ANY WARRANTY; without even the implied warranty of"
  puts "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the"
  puts "GNU General Public License for more details."
  puts ""
  puts "You should have received a copy of the GNU General Public License"
  puts "along with this program; if not, write to the Free Software"
  puts "Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA"
end

xOutFormat = "png"
xOutFile = nil
xGVPath = nil

oOpt = GetoptLong.new(
  ['--output-format', '-T', GetoptLong::REQUIRED_ARGUMENT],
  ['--output-file',   '-o', GetoptLong::REQUIRED_ARGUMENT],
  ['--path',          '-p', GetoptLong::REQUIRED_ARGUMENT],
  ['--help',          '-h', GetoptLong::NO_ARGUMENT],
  ['--version',       '-V', GetoptLong::NO_ARGUMENT]
)

begin
  oOpt.each_option do |xOpt, xValue|
    case xOpt
      when '--output-format'
        xOutFormat = xValue
      when '--output-file'
        xOutFile = xValue
      when '--path'
        xGVPath = xValue
      when '--help'
        usage( )
        exit
      when '--version'
        version( )
        exit
    end
  end
rescue GetoptLong::InvalidOption => e
  usage( )
  exit
end

xFile = ARGV[0]

if xFile.nil? == true
  usage( )
  exit
end

o = Rb2Gv::new( xGVPath )
o.parse( xFile )
o.out( xOutFormat, xOutFile )