#! /usr/bin/env ruby
#
# 15-441 Checkpoint 2 Script
# 15-441 Staff
#
# If you are connecting to linux.andrew.cmu.edu, you should explicitly specify the server IP address.
# Complaints -> email xil@cs.cmu.edu

require 'socket'
#$SAFE = 1

$SERVER = "127.0.0.1"
$PORT = 9034  

if ARGV.size == 0
    puts "Usage: ./checkpoint2 server_port [server_ip_addr]"
    exit
elsif ARGV.size >= 1

begin
    $PORT = Integer(ARGV[0])
rescue
    puts "The port number must be an integer!"
    exit
end
end

if ARGV.size >= 2
    $SERVER = ARGV[1].to_s()
end

puts "Server address - " + $SERVER + ":" + $PORT.to_s()


class ECHO

    def initialize(server, port, nick, channel)
        @server = server
        @port = port
        @nick = nick
        @channel = channel
    end

    def recv_data_from_server (timeout)
        pending_event = Time.now.to_i
        received_data = Array.new
        k = 0 
        flag = 0
        while flag == 0
            ## check for timeout
            time_elapsed = Time.now.to_i - pending_event
            if (time_elapsed > timeout)
                flag = 1
            end 
            ready = select([@echo], nil, nil, 0.0001)
            next if !ready
            for s in ready[0]
                if s == @echo then
                    next if @echo.eof
                    s = @echo.gets
                    received_data[k] = s
                    k= k + 1
                end
            end
        end
        return received_data
    end

    def test_echo (s)
        data=recv_data_from_server(2)
	if(data.size <= 0)
	    return false
	else
	    puts "<-- " + data[0]
	    if (data[0] = s)
	        return true
	    else
	        return false
	    end
	end
    end

    def test_silence(timeout)
        data=recv_data_from_server(timeout)
        if (data.size > 0)
            return false
        else
            return true
        end
    end
    
    def send(s)
        # Send a message to the echo server and print it to the screen
        puts "--> #{s}"
        @echo.send "#{s}\n", 0 
    end

    def connect()
        # Connect to the echo server
        @echo = TCPSocket.open(@server, @port)
    end

    def disconnect()
        @echo.close
    end
end


##
# The main program.  Tests are listed below this point.  All tests
# should call the "result" function to report if they pass or fail.
##

$total_points = 0

def test_name(n)
    puts "\n////// #{n} \\\\\\\\\\\\"
    return n
end

def result(n, passed_exp, failed_exp, passed, points)
    explanation = nil
    if (passed)
	print "(+) #{n} passed"
	$total_points += points
	explanation = passed_exp
    else
	print "(-) #{n} failed"
	explanation = failed_exp
    end

    if (explanation)
	puts ": #{explanation}"
    else
	puts ""
    end
end

def eval_test(n, passed_exp, failed_exp, passed, points = 1)
    result(n, passed_exp, failed_exp, passed, points)
    exit(0) if !passed
end


begin

echo1 =ECHO.new($SERVER, $PORT, '', '')
echo2 =ECHO.new($SERVER, $PORT, '', '')
echo3 =ECHO.new($SERVER, $PORT, '', '')

#######################################################
# Test 1: A single user
#######################################################
echo1.connect()
s1 = "This is the first test. Only one user"

tn = test_name("ECHO_SINGLE_USER")
echo1.send(s1)
#puts "<-- Testing echo with a single user..."
eval_test(tn, nil, nil, echo1.test_echo(s1), 3)

echo1.disconnect()

#######################################################
# Test 2: Two users
#######################################################
echo1.connect()
echo2.connect()

s1 = "This is the second test. Two users echo. I am xil"
s2 = "This is the second test. Two users echo. I am xzhang"

tn = test_name("ECHO_TWO_USERS")
echo1.send(s1)
echo2.send(s2)
eval_test(tn, nil, nil, echo2.test_echo(s2),1)
eval_test(tn, nil, nil, echo1.test_echo(s1),2)

echo1.disconnect()
echo2.disconnect()

#######################################################
# Test 3: Three users
#######################################################
echo1.connect()
echo2.connect()
echo3.connect()

s1 = "This is the third test Three users echo I am xil"
s2 = "This is the third test Three users echo I am xzhang"
s3 = "This is the third test Three users echo I am dan"

tn = test_name("ECHO_THREE_USERS")
echo1.send(s1)
echo2.send(s2)
echo3.send(s3)
eval_test(tn, nil, nil, echo3.test_echo(s2),1)
eval_test(tn, nil, nil, echo2.test_echo(s2),1)
eval_test(tn, nil, nil, echo1.test_echo(s1),2)

echo1.disconnect()
echo2.disconnect()
echo3.disconnect()

rescue Interrupt
rescue Exception => detail
    puts detail.message()
    print detail.backtrace.join("\n")
ensure
    puts "\nYour score: #{$total_points} / 10"
    puts "Remember to commit code into tags/checkpoint2 (case sensitive)"
end