require 'fileutils'
require 'date'
require 'nera_db_folders'
require 'nera_simulator'


module NERA

  # This class create & parse job scripts
  class JobScript
    
    # NERA::DbFolders object
    @db_folder
    
    #--------------------------------------
    #-class methods -----------------------
    #--------------------------------------

    # db_folder is the instance of DbFolders
    def initialize( db_folder)
      unless db_folder.instance_of?(NERA::DbFolders) then
        raise ArgumentError, "Argument must be an instance of NERA::DbFolders."
      end
      @db_folder = db_folder
    end
    
    # job script
    def job_script_body(job_info)
 ############## job_script ###################
job_script =<<"BODY"
#!/bin/bash
LANG=C
mkdir -p #{job_info[:job_script_id]}
cd #{job_info[:job_script_id]}
echo \"#---------- header of #{job_info[:job_id]} ----------\" > nera_status.rb
echo \"header = {\" >> nera_status.rb
echo \"    :database => '#{job_info[:database]}',\" >> nera_status.rb
echo \"    :job_id => #{job_info[:job_id]},\" >> nera_status.rb
echo \"    :simulator => '#{job_info[:simulator]}',\" >> nera_status.rb
echo \"    :simulator_id => #{job_info[:sim_id]},\" >> nera_status.rb
echo \"    :param_id => #{job_info[:param_id]},\" >> nera_status.rb
echo \"    :run_ids => #{job_info[:run_ids].inspect},\" >> nera_status.rb
echo \"    :parameters => {\" >> nera_status.rb
BODY

job_info[:params].each_pair do |key, value|
job_script += "echo \"        #{key.to_sym.inspect} => #{value.inspect.gsub(/\"/,'\"')},\" >> nera_status.rb\n"
end

job_script +=<<"BODY"
echo \"    },\" >> nera_status.rb
echo \"    :start_at => DateTime.parse( <<'NERA_DATE'.chomp )\" >> nera_status.rb
date >> nera_status.rb
echo \"NERA_DATE\" >> nera_status.rb
echo \"}\" >> nera_status.rb
echo \"body = {\" >> nera_status.rb
BODY

job_info[:run_ids].each_with_index do |run_id, i|
job_script +=<<"BODY"
echo \"    #---------- #{run_id} start ----------\" >> nera_status.rb
echo \"    #{run_id} => {\" >> nera_status.rb
echo \"        :seed => #{job_info[:seeds][i]}, :start_at => DateTime.parse( <<'NERA_START_AT'.chomp), :output => <<'NERA_OUTPUT', :finish_at => DateTime.parse( <<'NERA_FINISH_AT'.chomp)\" >> nera_status.rb
date >> nera_status.rb
echo \"NERA_START_AT\" >> nera_status.rb
echo \"#{job_info[:execs][i]}\"
mkdir -p #{run_id}
cd #{run_id}
{ time -p { #{job_info[:execs][i]};} } 2>> ../nera_status.rb
if test $? -ne 0; then { echo \"Exit abnormally!\" >> ../nera_status.rb; exit; } fi
cd ..
echo \"NERA_OUTPUT\" >> nera_status.rb
date >> nera_status.rb
echo \"NERA_FINISH_AT\" >> nera_status.rb
BODY
if i == job_info[:run_ids].length-1 then job_script += "echo \"    }\" >> nera_status.rb\n"
else job_script += "echo \"    },\" >> nera_status.rb\n" end
job_script += "echo \"    #---------- #{run_id} end ----------\" >> nera_status.rb\n"
end

job_script +=<<"BODY"
echo \"}\" >> nera_status.rb
echo \"footer = {\" >> nera_status.rb
echo \"    :host_name => <<'NERA_HOST'.chomp, :finish_at => DateTime.parse( <<'NERA_DATE'.chomp )\" >> nera_status.rb
hostname >> nera_status.rb
echo \"NERA_HOST\" >> nera_status.rb
date >> nera_status.rb
echo \"NERA_DATE\" >> nera_status.rb
echo "}" >> nera_status.rb
cd ..
tar cf #{job_info[:job_script_id]}.tar #{job_info[:job_script_id]}/
if test $? -ne 0; then { echo \"#Exit abnormally!\" >> ./nera_status.rb; exit; } fi
bzip2 #{job_info[:job_script_id]}.tar
if test $? -ne 0; then { echo \"Exit abnormally!\"; exit; } fi
rm -rf #{job_info[:job_script_id]}
BODY
############## job script ###################

      return job_script
    end
    private :job_script_body
    
    #--------------------------------------
    #-public instance methods--------------
    #--------------------------------------
    public
    # create job script --------------------
    def  create_script(job_id, sim_id, param_id, sim_inst, run_stat)
      unless job_id.is_a?(Integer) and sim_id.is_a?(Integer) and param_id.is_a?(Integer) 
        raise ArgumentError, "Each ID of Job, Simulation and Parameter  must be an Integer."
      end
      unless sim_inst.kind_of?(NERA::Simulator)
        raise ArgumentError, "Simulation_Instance must be a subclass of NERA::Simulator."
      else
        # if sim_inst.param == {}
        #   raise ArgumentError, "@param in Simulation_Instance must be set a parameter."
        # end
      end
      unless run_stat.is_a?(Array)
        raise ArgumentError, "Run_Status must be an Array."
      else 
        run_stat.each do | stat |
          unless stat.has_key?(:id) and stat.has_key?(:seed)
            raise ArgumentError, "Run Status must have keys, :id and :seed."
          end
        end
      end
      
      
      run_ids =[]
      seeds = []
      run_stat.each do |run_info|
        run_ids << run_info[:id]
        seeds << run_info[:seed]
      end

      job_info ={
        :job_id => job_id,
        :job_script_id => sprintf("j%06d",job_id),
        :database => File.basename( @db_folder.path_to_simulator_layer),
        :simulator => sim_inst.class.to_s,
        :sim_id => sim_id,
        :param_id => param_id,
        :params => sim_inst.param,
        # {:L => 256, :K => 0.22325, :tmax => 512},
        :run_ids => run_ids,
        :seeds => seeds,
        :execs => seeds.map do |sed|
          sim_inst.simulate_command( sed).split("\n").join(' && ').sub(/;$/,'')
        end
      }

      path_job_script = @db_folder.path_to_job_script( job_id)
      unless FileTest.directory?(@db_folder.path_to_job_layer)
        raise "must not happen"
      end
      if FileTest.exist?(path_job_script)
        raise "must not happen"
      end

      File.open(path_job_script,"w") do |io|
        io.puts job_script_body(job_info)
        io.flush
      end

      return path_job_script
    end
    
    # parse status file --------------------
    def parse_status(path_stat)
      unless path_stat.is_a?(String) and FileTest.exists?(path_stat)
        raise ArgumentError, "#{path_stat} is not valid status file."
      end
      
      str = ""
      File.open(path_stat).each do |line|
        str += line
      end
      header = {}
      body = {}
      footer = {}
      begin
        eval(str)
      rescue 
        raise RuntimeError, "This nera_status.rb is not valid."
      end
      job_info = header.merge( footer)

      body.each_pair do |run_id, info|
        info[:real_time] = 0.0
        info[:user_time] = 0.0
        info[:output].each_line do |line|
          if line =~ /^real [-+]?(?:[0-9]+(\.[0-9]*)?|(\.[0-9]+))([eE][-+]?[0-9]+)?/
            info[:real_time] = line.sub(/^real /,'').to_f
          elsif line =~ /^user [-+]?(?:[0-9]+(\.[0-9]*)?|(\.[0-9]+))([eE][-+]?[0-9]+)?/
            info[:user_time] += line.sub(/^user /,'').to_f
          end
        end
      end
      return job_info, body
    end

  end
end