#!/usr/bin/ruby

# Main program for preparing gsSearch (Making POSCAR (various composition))
#
# Written by k-fleak
#


class PrepareGS
  
  def initialize(compGrid)
    setCompArray(compGrid)
    calcNumAtom
    calcNumAtomArray
    getPOSCARcomp
  end
  
  
  private
  
  def getPOSCARcomp
    if !FileTest.exist?("./POSCAR.comp") then
      Dir::mkdir("./POSCAR.comp")
    else
      Dir.entries("./POSCAR.comp/").each do |files|
        if /POSCAR./ =~ files  and FileTest.file?("./POSCAR.comp/#{files}") then
          File.delete("./POSCAR.comp/#{files}")
        end
      end
    end
    
    @compArray.each do |comp|
      poscarComp = open("./POSCAR.comp/POSCAR.#{comp}", "w")
      poscar = open("./POFILE/POSCAR", "r")
      posComp = Array.new              
      poscar.each do |pos|
        if /NUMATOMS/ =~ pos then
          ptmp = pos.gsub(/NUMATOMS/, @numAtomArray[comp][0])
          posComp.push(ptmp)
        else
          posComp.push(pos)
        end
      end
      posComp.each do |pc|
        poscarComp.write(pc)
      end
      poscarComp.close
    end
    
  end
  
  def setCompArray(compGrid)
    @compArray = Array.new
    comp = compGrid.to_f
    while comp < 1.0
      @compArray.push(comp)
      comp += compGrid.to_f
    end
    @compArray.each do |ca|
      if ca > 0.99999 then
        @compArray.delete(ca)
      end
    end
  end
  
  def calcNumAtom
    poscar = open("./POFILE/POSCAR", "r")
    ntmp = 0
    poscar.each do |pos|
      unless pos.strip.empty? then
        ntmp += 1
      end
    end
    @numAtom = ntmp - 7
  end
  
  def calcNumAtomArray
    @numAtomArray = Hash.new
    @compArray.each do |comp|
      numAatom = (@numAtom * comp).to_i
      numBatom = (@numAtom - numAatom).to_i
      @numAtomArray[comp] = ["#{numAatom} #{numBatom} "]
    end
  end
  
end

pg = PrepareGS.new(ARGV[0])