#!/usr/bin/env ruby

def config
  Grader::Configuration.get_instance
end

def display_manual
  puts <<USAGE
Check similarity between submission
using: check_similar sub1 sub2
          -- or --
       check_similar problem_name
  sub1 and sub2   are submission IDs to be checked
  problem_name    will check all submissions of the problem wit problem short name is 'problem_name'

  The output are given as
    sub1.login, sub1.id, sub1.point, sub2.login, sub2.id, sub2.point, similarity

USAGE
end

def process_options_and_stop_file

  # Process 'help' option
  if (ARGV.length == 0) or ((ARGV.length==1) and (/help/.match(ARGV[0])))
    display_manual
    exit(0)
  end

  #default options
  options = {
    :dry_run => false,
  }


  if ARGV.length == 2
    options[:sub1] = ARGV[0].to_i
    options[:sub2] = ARGV[1].to_i
  elsif ARGV.length == 1
    options[:problem] = ARGV[0]
  end


  return options
end

def compare(sub1,sub2,full = sub1.problem.full_score)
  dis = @jarow.getDistance(sub1.source, sub2.source)
  puts [sub1.user.login,"##{sub1.id}",(sub1.points * 100.0 / full).to_i,
        sub2.user.login,"##{sub2.id}",(sub2.points * 100.0 / full).to_i,
        "#{dis * 100}%"].join(',')
end

#########################################
# main program
#########################################

options = process_options_and_stop_file

# load grader environment
GRADER_ENV = 'grading'
require File.join(File.dirname(__FILE__),'config/environment')

# boot rails, to be able to use the active record
RAILS_ENV = config.rails_env
require RAILS_ROOT + '/config/environment'

# load comparator
require 'fuzzystringmatch'
@jarow = FuzzyStringMatch::JaroWinkler.create( :native )

if options[:problem]
  p = Problem.where(name: options[:problem]).first
  unless p
    puts "cannot find problem #{options[:problem]}"
    exit(0)
  end
  subs = Submission.where(problem: p)
  full_score = p.full_score.to_i
  subs.each.with_index do |s1,i|
    puts "processing #{i+1} out of #{subs.length}"
    subs.each do |s2|
      if s1.user != s2.user
        compare(s1,s2,full_score)
      end
    end
  end
else
  sub1 = Submission.find(options[:sub1])
  sub2 = Submission.find(options[:sub2])
  compare(sub1,sub2)
end