#!/usr/bin/ruby

require 'fileutils'

def log(str='')
  if ENV['TALKATIVE']!=nil
    puts str
  end
  if ENV['GRADER_LOGGING']!=nil
    log_fname = ENV['GRADER_LOGGING']
    fp = File.open(log_fname,"a")
    fp.puts("judge: #{Time.new.strftime("%H:%M")} #{str}")
    fp.close
  end
end

problem_home = ENV['PROBLEM_HOME']

def execute(command, error_message="")
  if not system(command)
    msg = "ERROR: #{error_message}"
    log msg
    raise msg
  end
end

def call_and_log(error_message)
  begin
    yield
  rescue
    msg = "ERROR: #{error_message}"
    log msg
    raise msg
  end
end

def clear_and_create_empty_dir(dir)
  FileUtils.rm_rf(dir, :secure => true)
  call_and_log("Cannot make directory #{dir}.") { FileUtils.mkdir(dir) }
end

# ARGV[0] --- language
# ARGV[1] --- program source file
# ARGV[2] --- test result directory
# ARGV[3] --- sandbox directory

if ARGV.length < 2 || ARGV.length > 4
  puts "Usage: judge <language> <program-source> [<test-result-directory>] [<sandbox-directory>]"
  puts "  <sandbox-directory> is defaulted to ./sandbox"
  puts "  <test-result-directory> is defaulted to ./test-result"
  puts "WARNING: The judge script will forcefully create the (implicitly and explicitly) specified directories and remove anything inside it."
  exit(127)
end

language = ARGV[0]
if language != "c" && language != "c++" && language != "pas"
  log "You specified a language that is not supported: #{language}."
  exit(127)
end

source_file = ARGV[1]
if File.exist?(source_file) == false
  log "The source file does not exist."
  exit(127)
end

log "Making test result and sandbox directories..."

current_dir = FileUtils.pwd
current_dir.strip!

if ARGV.length >= 3
  test_result_dir = ARGV[2]
else
  test_result_dir = "#{current_dir}/test-result"
end

log "Test result directory: #{test_result_dir}"
clear_and_create_empty_dir(test_result_dir)

if ARGV.length >= 4
  sandbox_dir = ARGV[3]
else
  sandbox_dir = "#{current_dir}/sandbox"
end
log "Sandbox directory: #{sandbox_dir}"
clear_and_create_empty_dir(sandbox_dir)

# Compile
log
log "Compiling..."
call_and_log("Cannot copy the source file to #{sandbox_dir}") { 
  FileUtils.cp(source_file, sandbox_dir) 
}
begin 
  Dir.chdir sandbox_dir
rescue
  log "ERROR: Cannot change directory to #{sandbox_dir}."
  exit(127)
end
execute("#{problem_home}/script/compile #{language} #{source_file}", "Compilation error!")
compile_message = open("compiler_message").read
compile_message.strip!
call_and_log("Cannot move the compiler message to #{test_result_dir}.") {
  FileUtils.mv("compiler_message", test_result_dir)
}
if !FileTest.exist?("a.out")
  log "Cannot compile the source code. See message in #{test_result_dir}/compile_message"
  exit(127)
else
  call_and_log("Cannot move the compiled program to #{test_result_dir}") {
    FileUtils.mv("a.out",test_result_dir)
  }
  FileUtils.rm_rf("#{sandbox_dir}/.")
end

require "#{problem_home}/script/test_dsl.rb"
load "#{problem_home}/test_cases/all_tests.cfg"
problem = Problem.get_instance

if problem.well_formed? == false
  log "The problem specification is not well formed."
  exit(127)
end

# Doing the testing.
(1..(problem.num_tests)).each do |test_num|

  $stdout.print "[#{test_num}]"
  $stdout.flush

  log "Test number: #{test_num}"
  call_and_log("Cannot copy the compiled program into #{sandbox_dir}") {
    FileUtils.cp("#{test_result_dir}/a.out", sandbox_dir)
  }
  begin
    execute("#{problem_home}/script/run #{language} #{test_num}", "Error occured during execution of the run script")
  rescue
    # do nothing
  end
  call_and_log("Cannot create directory #{test_result_dir}/#{test_num}") {
    FileUtils.mkdir "#{test_result_dir}/#{test_num}"
  }
  call_and_log("Cannot copy the result file into #{test_result_dir}/#{test_num}") {
    FileUtils.mv "#{sandbox_dir}/result", "#{test_result_dir}/#{test_num}"
  }
  call_and_log("Cannot copy the comment file into #{test_result_dir}/#{test_num}") {
    FileUtils.mv "#{sandbox_dir}/comment", "#{test_result_dir}/#{test_num}"
  }
  call_and_log("Cannot copy the output file into #{test_result_dir}/#{test_num}") {
    FileUtils.mv "#{sandbox_dir}/output.txt", "#{test_result_dir}/#{test_num}"
  }
  call_and_log("Cannot clear #{sandbox_dir}") {
    FileUtils.rm_rf(Dir.glob("#{sandbox_dir}/*"), :secure => true)
  }
end

$stdout.print "[done]\n"

# Grade
log
log "Grading..."
begin
  Dir.chdir test_result_dir
rescue
  log "ERROR: Cannot change directory to #{test_result_dir}."
  exit(127)
end
execute("#{problem_home}/script/grade", "An error occured during grading!")

log
log "All done!"