#! /usr/bin/env ruby
# coding: utf-8

require "helper"
require "stringio"

class TC_Incar < Test::Unit::TestCase
  def setup
    @i00 = VaspUtils::Incar.new
  end
  
  def test_self_parse
    io = StringIO.new
    io.puts "# SCF input for VASP"
    io.puts "# Note that VASP uses the FIRST occurence of a keyword"
    io.puts "# if single point calc, IBRION = -1, NSW = 0, and comment out ISIF"
    io.puts ""
    io.puts " SYSTEM = Untitled (VASP)"
    io.puts "   PREC = High"
    io.puts " IBRION = 2"
    io.puts "    NSW = 100        #maximum number of ionic steps"
    io.puts "   ISIF = 2"
    io.puts "  ENCUT = 400"
    io.puts "   NELM = 60         #maximum number of electronic steps"
    io.puts " NELMIN = 2          #minimum number of electronic steps"
    io.puts "  EDIFF = 1.0e-05"
    io.puts " EDIFFG = -0.02"
    io.puts "VOSKOWN = 1"
    io.puts " NBLOCK = 1"
    io.puts "  ISPIN = 1          #1:non spin polarized, 2:spin polarized"
    io.puts " INIWAV = 1"
    io.puts " ISTART = 1"
    io.puts " ICHARG = 1"
    io.puts "  LWAVE = .TRUE."
    io.puts " LCHARG = .FALSE."
    io.puts " ISMEAR = 0"
    io.puts "  SIGMA = 0.1"
    io.puts "  IALGO = 38         #38:KosugiAlgorithm, 48:RMM-DIIS"
    io.puts "  LREAL = Auto       #fast & not accurate"
    io.puts "    NGX = 36"
    io.puts "    NGY = 36"
    io.puts "    NGZ = 42"
    io.rewind
    incar = VaspUtils::Incar.parse(io)
    #assert_equal(incar["SYSTEM"], "Untitled (VASP)")
    assert_equal(incar["SYSTEM"    ], "Untitled")
    assert_equal(incar["PREC"      ], "High")
    assert_equal(incar["IBRION"    ], 2)
    assert_equal(incar["NSW"       ], 100)
    assert_equal(incar["ISIF"      ], 2)
    assert_equal(incar["ENCUT"     ], 400)
    assert_equal(incar["NELM"      ], 60)
    assert_equal(incar["NELMIN"    ], 2)
    assert_equal(incar["EDIFF"     ], 1.0e-05)
    assert_equal(incar["EDIFFG"    ], -0.02)
    assert_equal(incar["VOSKOWN"   ], 1)
    assert_equal(incar["NBLOCK"    ], 1)
    assert_equal(incar["ISPIN"     ], 1)
    assert_equal(incar["INIWAV"    ], 1)
    assert_equal(incar["ISTART"    ], 1)
    assert_equal(incar["ICHARG"    ], 1)
    assert_equal(incar["LWAVE"     ], true ) #".TRUE."
    assert_equal(incar["LCHARG"    ], false ) #".FALSE."
    assert_equal(incar["ISMEAR"    ], 0)
    assert_equal(incar["SIGMA"     ], 0.1)
    assert_equal(incar["IALGO"     ], 38)
    assert_equal(incar["LREAL"     ], "Auto")
    assert_equal(incar["NGX"       ], 36)
    assert_equal(incar["NGY"       ], 36)
    assert_equal(incar["NGZ"       ], 42)
  end

  def test_self_load_file
    incar = VaspUtils::Incar.load_file "test/incar/INCAR.01"
    assert_equal(incar["SYSTEM"    ], "Untitled")
    assert_equal(incar["PREC"      ], "High")
    assert_equal(incar["IBRION"    ], 2)
    assert_equal(incar["NSW"       ], 0)
    assert_equal(incar["ISIF"      ], 2)
    assert_equal(incar["ENCUT"     ], 400)
    assert_equal(incar["NELM"      ], 60)
    assert_equal(incar["NELMIN"    ], 2)
    assert_equal(incar["EDIFF"     ], 1.0e-05)
    assert_equal(incar["EDIFFG"    ], -0.02)
    assert_equal(incar["VOSKOWN"   ], 1)
    assert_equal(incar["NBLOCK"    ], 1)
    assert_equal(incar["ISPIN"     ], 1)
    assert_equal(incar["INIWAV"    ], 1)
    assert_equal(incar["ISTART"    ], 1)
    assert_equal(incar["ICHARG"    ], 1)
    assert_equal(incar["LWAVE"     ], true ) #".TRUE."
    assert_equal(incar["LCHARG"    ], false ) #".FALSE."
    assert_equal(incar["ISMEAR"    ], 0)
    assert_equal(incar["SIGMA"     ], 0.1)
    assert_equal(incar["IALGO"     ], 38)
    assert_equal(incar["LREAL"     ], "Auto")
    assert_equal(incar["NGX"       ], 36)
    assert_equal(incar["NGY"       ], 36)
    assert_equal(incar["NGZ"       ], 42)

    # not exist
    assert_raise(Errno::ENOENT){VaspUtils::Incar.load_file("")}
  end

  def test_append
    setting = VaspUtils::Setting.new("test/incar/dot.vasputils")

    incar = VaspUtils::Incar.new
    incar.clear
    assert_equal({}, incar)

    incar.append("base", setting)
    correct = {
      'SYSTEM' =>  "Generated by VaspUtils::Incar",
      'PREC' =>    "High",
      'NELM' =>    60,
      'NELMIN' =>  2,
      'EDIFF' =>   1.0e-05,
      'VOSKOWN' => 1,
      'NBLOCK' =>  1,
      'INIWAV' =>  1,
      'ISTART' =>  1,
      'ICHARG' =>  1,
      'LWAVE' =>   false,
      'LCHARG' =>  false,
      'IALGO' =>   38,
      'LREAL' =>   "Auto",
      'ISMEAR' =>  -5,
    }
    assert_equal(correct, incar)

    incar.append("singlepoint", setting)
    correct = {
      'SYSTEM' =>  "Generated by VaspUtils::Incar",
      'PREC' =>    "High",
      'NELM' =>    60,
      'NELMIN' =>  2,
      'EDIFF' =>   1.0e-05,
      'VOSKOWN' => 1,
      'NBLOCK' =>  1,
      'INIWAV' =>  1,
      'ISTART' =>  1,
      'ICHARG' =>  1,
      'LWAVE' =>   false,
      'LCHARG' =>  false,
      'IALGO' =>   38,
      'LREAL' =>   "Auto",
      'ISMEAR' =>  -5,
      'IBRION' =>  -1,
      'NSW' =>     0
    }
    assert_equal(correct, incar)


    incar = VaspUtils::Incar.new
    incar.clear
    incar.append("spin1", setting)
    assert_equal({"ISPIN" => 1}, incar)

    incar.append("spin2", setting)
    assert_equal({"ISPIN" => 2}, incar)
  end

  def test_dump
    incar = VaspUtils::Incar.new
    incar["SYSTEM"] = "dummy"
    incar["PREC"  ] = "High"
    incar["ENCUT" ] = 400
    incar["EDIFF" ] = 1.0e-05
    incar["LREAL" ] = true
    correct = [
      "SYSTEM   = dummy",
      "PREC     = High",
      "ENCUT    = 400",
      "EDIFF    = 1.0e-05",
      "LREAL    = .TRUE.",
    ].join("\n")
    assert_equal( correct, incar.dump )

    assert_equal( correct, incar.dump(nil))

    outfile = "test/incar/tmp.incar"
    FileUtils.rm outfile if File.exist? outfile
    File.open(outfile, "w") { |io| incar.dump(io) }
    assert_equal( correct, File.open(outfile).read)
    FileUtils.rm outfile if File.exist? outfile

  end

end