# Copyright (C) 2003, 2004, 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 'tempfile'
require 'mkmf'

require 'graphviz/node'
require 'graphviz/edge'
require 'graphviz/attrs'
require 'graphviz/constants'

class GraphViz 
  include Constants

  public

  ## Var: Output format (dot, png, jpeg, ...)
  @format
  ## Var: Output file name
  @filename
  ## Var: program to use (dot|twopi)
  @prog
  ## Var: program path
  @path

  ## Var: Graph name
  @name

  ## Var: defined attributs
  @graph
  @node
  @edge
  attr_accessor :node, :edge

  @elements_order
  
  ##
  # Create a new node
  #
  # In:
  #   xNodeName : Name of the new node
  #   *hOpt : Node attributs
  # 
  # Return the GraphViz::Node object created
  #
  def add_node( xNodeName, *hOpt )
    @hoNodes[xNodeName] = GraphViz::Node::new( xNodeName, self )
   
    if hOpt.nil? == false and hOpt[0].nil? == false
      hOpt[0].each do |xKey, xValue|
        @hoNodes[xNodeName][xKey.to_s] = xValue
      end
    end

    @elements_order.push( { 
      "type" => "node", 
      "name" => xNodeName,
      "value" => @hoNodes[xNodeName] 
    } )
    
    return( @hoNodes[xNodeName] )
  end

  ##
  # Create a new edge
  # 
  # In:
  #   oNodeOne : First node
  #   oNodeTwo : Second Node
  #   *hOpt : Edge attributs
  #
  def add_edge( oNodeOne, oNodeTwo, *hOpt )
    oEdge = GraphViz::Edge::new( oNodeOne, oNodeTwo, self )
    
    if hOpt.nil? == false and hOpt[0].nil? == false
      hOpt[0].each do |xKey, xValue|
        oEdge[xKey.to_s] = xValue
      end
    end

    @elements_order.push( { 
      "type" => "edge", 
      "value" => oEdge
    } )
    
    @loEdges.push( oEdge )
    return( oEdge )
  end

  # 
  # Create ŕ new graph
  # 
  # In:
  #   xGraphName : Graph name
  #   *hOpt : Graph attributs
  #
  def add_graph( xGraphName, *hOpt )
    @hoGraphs[xGraphName] = GraphViz::new( xGraphName, :parent => self, :type => @oGraphType )
   
    if hOpt.nil? == false and hOpt[0].nil? == false
      hOpt[0].each do |xKey, xValue|
        @hoGraphs[xGraphName][xKey.to_s] = xValue
      end
    end

    @elements_order.push( { 
      "type" => "graph", 
      "name" => xGraphName,
      "value" => @hoGraphs[xGraphName] 
    } )
    
    return( @hoGraphs[xGraphName] )
  end

  def method_missing( idName, *args, &block )
    xName = idName.id2name
  
    rCod = nil
    
    if block
      # Creating a cluster named '#{xName}'
      rCod = add_graph( xName, args[0] )
      yield( rCod )
    else
      # Create a node named '#{xName}' or search for a node, edge or cluster
      return( @hoNodes[xName] ) if @hoNodes.keys.include?( xName )
      return( @hoGraphs[xName] ) if @hoGraphs.keys.include?( xName )
      
      rCod = add_node( xName, args[0] )
    end

    return rCod
  end
  
  # 
  # Set value +xValue+ to the graph attribut +xAttrName+
  # 
  def []=( xAttrName, xValue )
    @graph[xAttrName] = xValue
  end

  # 
  # Get the value of the graph attribut +xAttrName+
  # 
  def []( xAttrName )
    return( @graph[xAttrName].clone )
  end
  
  # 
  # Generate the graph
  # 
  # Options :
  #   :output : Output format (Constants::FORMATS)
  #   :file : Output file name
  #   :use : Program to use (Constants::PROGRAMS)
  #   :path : Program PATH
  # 
  def output( *hOpt )
    xDOTScript = ""
    xLastType = nil
    xSeparator = ""
    xData = ""

    @elements_order.each { |kElement|
      if xLastType.nil? == true or xLastType != kElement["type"]
        
        if xData.length > 0 
          case xLastType
            when "graph_attr"
              xDOTScript << "  " + xData + ";\n"
  
            when "node_attr"
              xDOTScript << "  node [" + xData + "];\n"
            
            when "edge_attr"
              xDOTScript << "  edge [" + xData + "];\n"
          end
        end
        
        xSeparator = ""
        xData = ""
      end

      xLastType = kElement["type"]

      #Modified by
      #Brandon Coleman 
      #verify value is NOT NULL
      if kElement["value"] == nil then
        raise ArgumentError, "#{kElement["name"]} has a nil value!"
      end
      
      case kElement["type"]
        when "graph_attr"
          xData << xSeparator + kElement["name"] + " = \"" + kElement["value"] + "\""
          xSeparator = "; "

        when "node_attr"
          xData << xSeparator + kElement["name"] + " = \"" + kElement["value"] + "\""
          xSeparator = ", "

        when "edge_attr"
          xData << xSeparator + kElement["name"] + " = \"" + kElement["value"] + "\""
          xSeparator = ", "

        when "node"
          xDOTScript << "  " + kElement["value"].output() + "\n"

        when "edge"
          xDOTScript << "  " + kElement["value"].output( @oGraphType ) + "\n"

        when "graph"
          xDOTScript << kElement["value"].output() + "\n"

        else
          raise ArgumentError, "Don't know what to do with element type '#{kElement['type']}'"
      end
    }
    
    xDOTScript << "}"

    if @oParentGraph.nil? == false
      xDOTScript = "subgraph #{@name} {\n" << xDOTScript

      return( xDOTScript )
    else
      if hOpt.nil? == false and hOpt[0].nil? == false
        hOpt[0].each do |xKey, xValue|
          case xKey.to_s
            when "output"
              if FORMATS.index( xValue ).nil? == true
                raise ArgumentError, "output format '#{xValue}' invalid"
              end
              @format = xValue
            when "file"
              @filename = xValue
            when "use"
              if PROGRAMS.index( xValue ).nil? == true
                raise ArgumentError, "can't use '#{xValue}'"
              end
              @prog = xValue
            when "path"
              @path = xValue
            else
              raise ArgumentError, "option #{xKey.to_s} unknown"
          end
        end
      end
  
      xDOTScript = "#{@oGraphType} #{@name} {\n" << xDOTScript

      if @format != "none"
        ## Act: Save script and send it to dot
        t = Tempfile::open( File.basename($0) + "." )
        t.print( xDOTScript )
        t.close
        
        #cmd = find_executable( @prog )
        #cmd = find_executable0( @prog )
        cmd = find_executable( )
        if cmd == nil
          raise StandardError, "GraphViz not installed or #{@prog} not in PATH. Install GraphViz or use the 'path' option"
        end
        
        xFile = ""
        xFile = "-o #{@filename}" if @filename.nil? == false
        xCmd = "#{cmd} -T#{@format} #{xFile} #{t.path}"
        
        f = IO.popen( xCmd )
        print f.readlines
        f.close
      else
        puts xDOTScript
      end
    end
  end
  
  def set_position( xType, xKey, xValue ) #:nodoc:
    @elements_order.push( { 
      "type" => "#{xType}_attr", 
      "name" => xKey,
      "value" => xValue 
    } )
  end
  
## ----------------------------------------------------------------------------

  private 

  ## Var: Nodes, Edges and Graphs tables
  @hoNodes
  @loEdges
  @hoGraphs

  ## Var: Parent graph
  @oParentGraph

  ## Var: Type de graphe (orienté ou non)
  @oGraphType
  
  # 
  # Create a new Graphviz object
  # 
  # Options :
  #   :output : Output format (Constants::FORMATS)
  #   :file : Output file name
  #   :use : Program to use (Constants::PROGRAMS)
  #   :path : Program PATH
  #   :parent : Parent graph
  #   :type : Graph type (Constants::GRAPHTYPE)
  # 
  def initialize( xGraphName, *hOpt )
    @format   = "dot"
    @filename = nil
    @prog     = "dot"
    @path     = nil
    @name     = xGraphName
    
    @elements_order = Array::new()

    @oParentGraph = nil
    @oGraphType   = "digraph"
    
    @hoNodes  = Hash::new()
    @loEdges  = Array::new()
    @hoGraphs = Hash::new()
    
    @node  = GraphViz::Attrs::new( self, "node",  NODESATTRS  )
    @edge  = GraphViz::Attrs::new( self, "edge",  EDGESATTRS  )
    @graph = GraphViz::Attrs::new( self, "graph", GRAPHSATTRS )

    if hOpt.nil? == false and hOpt[0].nil? == false
      hOpt[0].each do |xKey, xValue|
        case xKey.to_s
          when "output"
            if FORMATS.index( xValue ).nil? == true
              raise ArgumentError, "output format '#{xValue}' invalid"
            end
            @format = xValue
          when "use"
            if PROGRAMS.index( xValue ).nil? == true
              raise ArgumentError, "can't use '#{xValue}'"
            end
            @prog = xValue
          when "file"
            @filename = xValue
          when "parent"
            @oParentGraph = xValue
          when "type"
            if GRAPHTYPE.index( xValue ).nil? == true
              raise ArgumentError, "graph type '#{xValue}' unknow"
            end
            @oGraphType = xValue
          when "path"
            @path = xValue
          else
            self[xKey.to_s] = xValue
        end
      end
    end
  end
  
  def find_executable( ) #:nodoc:
    cmd = find_executable0( @prog )
    if cmd == nil and @path != nil
      __cmd = File.join( @path, @prog )
      cmd = __cmd if File.executable?( __cmd )
    end
    return cmd
  end
end