#!/usr/bin/env ruby
# Copyright (C) 2005 - 2012 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 'rubygems'
require 'getoptlong'
require 'graphviz'
require 'graphviz/constants'
require 'rbconfig'
require 'mkmf'

DEBUG = false

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

  def initialize( xGVPath, xUse = "dot", xStops = [] )
    @oGraph = GraphViz::new( "G", :path => xGVPath, :use => xUse )
    # @oGraph['size'] = '10,10'
    @hxNodes = Hash::new( )
    @hxEdge = Array::new( )
    @lxStops = xStops
  end

  public
  def parse( xFile )
    @hxNodes[xFile] = gv_newNode( xFile, "box", "forestgreen" )
    puts "+ Node #{xFile}" if DEBUG

    parseFile( xFile, nil, xFile )
  end

  def out( xFormat = "dot", xFile = nil )
    if xFile.nil?
      @oGraph.output( xFormat => String )
    else
      @oGraph.output( xFormat => xFile )
    end
  end

  private
  def gv_newNode( xNode, xShape = "box", xColor = nil )
    xNodeName = xNode.gsub( /[^a-zA-Z0-9]/, "_" )
    if xColor.nil?
      @oGraph.add_nodes( xNodeName, "label" => xNode, "shape" => xShape )
    else
      @oGraph.add_nodes( 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|bundle|dll)$/.match( xRbLib )
      match = /^(.*)\.([^\.]*)$/.match(xRbLib)
      xRbFile, xExt = match[1], [match[2]]
    else
      xRbFile = xRbLib
    end

    xExt.each do |e|
      xRbFileWithExt = xRbFile + "." + e

      # Search in "standard" paths
      xPath.each do |xDir|
        xCurrentPath = RbConfig::expand( RbConfig::CONFIG[xDir] )
        xFileFound = File.join( xCurrentPath, xRbFileWithExt )
        if File.exist?( xFileFound )
          return xFileFound
        end
      end

      # Search in "rubygems" :: This is not utile but...
      Gem::Specification.find_all do |spec|
        if spec == xLib
          spec.require_paths.unshift spec.bindir if spec.bindir
          xPath = spec.require_paths.map do |path|
            File.join spec.full_gem_path, path
          end
          xPath.each do |xCurrentPath|
            xFileFound = File.join( xCurrentPath, xRbFileWithExt )
            if File.exist?( xFileFound )
              return xFileFound
            end
          end
        end
      end
    end

    return nil
  end

  def parseFile( xFile, xFromFile = nil, xLib = nil )

    if xFromFile
      puts "Parse #{xFile} required in #{xFromFile} :" if DEBUG
    else
      puts "Parse #{xFile} :" if DEBUG
    end

    File.open(xFile, 'r').each_line do |xLine|
      if lxLineMatch = REQUIRE.match( xLine )
        xRequiredLib = lxLineMatch[2].gsub( /\.(rb|so)$/, "" )

        if not @hxNodes.has_key?( xRequiredLib )
          puts "  + Node #{xRequiredLib}" if DEBUG

          xRequiredFile = getLibraryPath( xRequiredLib )
          if xRequiredFile
            unless @lxStops.include?(xRequiredLib)
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib )
              parseFile( xRequiredFile, xFile, xRequiredLib )
            else
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib, "invhouse", "deepskyblue" )
            end
          else
            if getLibraryPath( xRequiredLib, ["so", "bundle", "dll"] ) == nil
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib, "box", "red" )
            else
              @hxNodes[xRequiredLib] = gv_newNode( xRequiredLib, "box", "grey" )
            end
          end

        end

        puts "  + Edge #{xLib} -> #{xRequiredLib}" if DEBUG
        unless @hxEdge.include?( "#{@hxNodes[xLib].id}-#{@hxNodes[xRequiredLib].id}" )
          @oGraph.add_edges( @hxNodes[xLib], @hxNodes[xRequiredLib] )
          @hxEdge << "#{@hxNodes[xLib].id}-#{@hxNodes[xRequiredLib].id}"
        end
      end
    end

  end

end

def usage
  puts "usage: ruby2gv [-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 "-u, --use PROGRAM             Program to use (default: dot)"
  puts "-s, --stop LIB[,LIB, ...]     Stop on libs"
  puts "-V, --version                 Show version"
  puts "-h, --help                    Show this usage message"
end

def version
  puts "Ruby2GraphViz v#{GraphViz::Constants::RGV_VERSION}, (c)2005, 2009, 2010 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 = ""
xUse = "dot"
xStops = []

oOpt = GetoptLong.new(
  ['--output-format', '-T', GetoptLong::REQUIRED_ARGUMENT],
  ['--output-file',   '-o', GetoptLong::REQUIRED_ARGUMENT],
  ['--path',          '-p', GetoptLong::REQUIRED_ARGUMENT],
  ['--use',           '-u', GetoptLong::REQUIRED_ARGUMENT],
  ['--stop',          '-s', 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 '--use'
        xUse = xValue
      when '--stop'
        xStops = xValue.split( "," ).map{ |x| x.strip }
      when '--help'
        usage( )
        exit
      when '--version'
        version( )
        exit
    end
  end
rescue GetoptLong::InvalidOption
  usage( )
  exit
end

xFile = ARGV[0]

if xFile.nil?
  usage( )
  exit
end

o = Rb2Gv::new( xGVPath, xUse, xStops )
o.parse( xFile )
result = o.out( xOutFormat, xOutFile )
puts result unless result.nil?