#readlog.rb reads production.log, searches for lines containing "teacher:" and
#prints out the part of the line that follows

require 'optparse'
class CatArguments < Hash
 def initialize(args)
	super()
	self[:logfile] = "production.log"
	self[:controlstr]= "teacher:"
	self[:ip]=nil
	opts = OptionParser.new do |opts|
		opts.banner = "Usage: #$0 [options] "
		opts.on('-l','--logfile [STRING]',
			'default is production.log') do |s|
			self[:logfile]=s
		end
		opts.on('-s', '--controlstr [STRING]',
			'default is teacher:')	do |s|
				self[:controlstr] = s
		end
		opts.on('-i','--ip [STRING]',
			'default is all') do |s|
			self[:ip]=s
		end
		opts.on_tail('-h', '--help',
		'display this help and exit') do
			puts opts
			exit
		end
	end

 opts.parse!(args)
 end
end

arguments = CatArguments.new(ARGV)
logfile=arguments[:logfile]
controlstr=arguments[:controlstr]
limitip=arguments[:ip]
r=%r~#{controlstr}(.*)~
newsum={}
	IO.foreach(logfile) do |nk|
#		p nk
		if nk.match(r) #controlstr found in string
#			p "raw #{$1}"
			s=$1
			if s=~ /for ([\d\.]+).*\/(\d+)$/ || s=~ /from ([\d\.]+).*\/(\d+)$/
				ip=$1
				secs=$2
#				p ip+secs
				if !limitip || (limitip == ip)
					if s=~/new problem/ 
						#a new sum was generated for an ip of interest
						newsum[ip]= secs
	#					p s
					elsif start=newsum[ip] 
						time_spent= secs.to_i - start.to_i
						p "After #{time_spent} seconds: #{s}"
					end
				end
			end
		end
	end