# Created May 98 by Ahmed Helmy; updated June 98
# topology generator class
Class TGproc usage { } {	puts stderr {usage: topology [options]where options are given as: -key valueexample options:-outfile mytopo -type random -nodes 50 -method pure-random"topology -h" help}	return#	exit 1}proc detailed-usage { } {puts {usage: topology [-<key 1> <value 1> -<key 2> <value 2> -<key n> <value n>]example options: -generator itm -outfile myfile -type random -nodes 20 -connection_prob 0.6 keys and corresponding values:-generator  possible value: itm (default) [the georgia tech topology generator]  [note: you need to invoke itm and sgb2ns, e.g. by setting your path]-outfile [the output file that will contain the ns script describing the	  generated topology. This must be given.]-type  possible values: random (default), transit_stub-seed  possible values: integer (default = random [uses ns-random])
-nodes [the number of nodes in the topology; used with `-type random']  possible values: integer (default = 50 with random, 100 with   transit-stub)-scale [used by itm to place nodes in topologies] (default = nodes)-method [the node connection/linking method; used with `-type random']  possible values: waxman1, waxman2, pure-random, doar-leslie, exponential,                    and  locality (default = pure-random)-connection_prob [the connection probability between nodes; used in        all methods] [this sometimes is called `alpha']  possible values: 0.0 <= connection_prob <= 1.0 (default = 0.5)-beta [used only with waxman1, waxman2, doar-leslie and locality]  possible values: 0.0 <= beta (default = 0.5)-gamma [used only with doar-leslie and locality]  possible values: 0.0 <= gamma (default = 0.5)  }}proc itm-random-help { } {	puts {Comment from ITM, on edge connection methods:   1. Edge is placed between two nodes by a probabilistic method, which      is determined by the "method" parameter.  Edge is placed with      probability p, where p is calculated by one of the methods below,      using:        alpha, beta, gamma: input parameters,        L is scale * sqrt(2.0): the max distance between two points,        d: the Euclidean distance between two nodes.        e: a random number uniformly distributed in [0,L]       Method 1: (Waxman's RG2, with alpha,beta)           p = alpha * exp(-e/L*beta)      Method 2: (Waxmans's RG1, with alpha,beta)           p = alpha * exp(-d/L*beta)      Method 3: (Pure random graph)           p = alpha      Method 4: ("EXP" - another distance varying function)           p = alpha * exp(-d/(L-d))      Method 5: (Doar-Leslie, with alpha,beta, gamma)           p = (gamma/n) * alpha * exp(-d/(L*beta))      Method 6: (Locality with two regions)           p = alpha     if d <= L*gamma,           p = beta      if d > L*gamma    2. Constraints        0.0 <=  alpha  <= 1.0  [alpha is a probability]        0.0 <= beta            [beta is nonnegative]        0.0 <= gamma           [gamma is nonnegative]        n <  scale*scale       [enough room for nodes]  }}proc itm-transit-stub-help { } {	puts {Parameters for transit_stub topology by itm:-stubs_per_transit [number of stubs per transit node] (default = 3)-ts_extra_edges [number of extra transit-stub edges] (default = 0)-ss_extra_edges [number of extra stub-stub edges] (default = 0) -transit_domains [number of transit domains] (default = 1)-domains_scale [top level scale used by ITM] (default = 20)* Connectivity of domains [similar to the random topology parameters]-domains_method (default = pure-random)-domains_connection_prob (default = 1.0) [fully connected]-domains_beta (default = 0.5)-domains_gamma (default = 0.5)
* Connectivity of transit nodes:
-transit_nodes (default = 4)
-transit_scale (default = 20)
-transit_method (default = pure-random)
-transit_connection_prob (default = 0.6)
-transit_beta (default = 0.5)
-transit_gamma (default = 0.5)

* Connectivity of stub nodes:
-stub_nodes (default = 8)
-stub_method (default = pure-random)
-stub_connection_prob (default = 0.4)
-stub_beta (default = 0.5)
-stub_gamma (default = 0.5)

* Total number of nodes is computed as follows:      
 nodes=transit_domains * transit_nodes * (1 + stubs_per_transit * stub_nodes)

 for example, for the above default settings we get:
        1 * 4 ( 1 + 3 * 8 ) = 100 nodes
  }

}

proc help-on-help { } {
	puts {Help available for random, transit stub, and edge connection method.

Help usage "topology -h <i>" 
where: 
<i> = 1 for random, 2 for transit stub, and 3 for edge connection method.
  }
}

proc help { x } {
	switch $x {
		1 { detailed-usage }
		2 { itm-transit-stub-help }
		3 { itm-random-help }
		default { puts "invalid help option"; help-on-help } 
	}
}

proc topology { args } {
	set len [llength $args]

	if $len {
	    set key [lindex $args 0]
            if {$key == "-?" || $key == "--help" || $key == "-help" \
			|| $key == "-h" } {
				if { [set arg2 [lindex $args 1]] == "" } {
					usage
					help-on-help
				} else {
                        	help $arg2
				}
			return
                }
	}

        if [expr $len % 2] {
                # if number is odd => error !
                puts "fewer number of arguments than needed in \"$args\""
                usage
		return
        }

        # default topology generator
        set generator itm

        if { $args != "" && [lindex $args 0] == "-generator" } {
		set generator [lindex $args 1]
		set args [lreplace $args 0 1]
	}

	# check if the generator type exists
	if [catch {set tg [TG/$generator info instances]}] {
		puts "unknown generator type $generator"
		usage
		return
	}
	if { $tg == "" } {
		set tg [new TG/$generator]
	}
	if ![llength $args] {
		$tg create
	} else {
		$tg create $args
	}
	ScenGen setTG $tg
}

Class TG/itm -superclass TG

TG/itm instproc init { } {
	$self next
}

TG/itm instproc default_options { } {
	# default set may not be complete for now.. !XXX
	$self instvar opt_info

	set opt_info {
		# init file to -1, must be supplied by input
		outfile -1

		# number of graphs and seed
		# flat random
		type random

		# number should not be changed by input... should be left 
		# as 1, and a tcl loop may create multiple graphs... left it as 
		# place holder in case this may change later.. !
		number 1
		# seed is randomized later if not entered as input
		seed -1

		nodes 50
		# if not entered assign to nodes later 
		scale -1 
		
		method pure-random
		connection_prob 0.5

		beta 0.5
		gamma 0.5

		# defaults for transit stub
	# total number of nodes is:
	# transit_domains * transit_nodes * (1 + stubs_per_transit * stub_nodes)
	# 1 * 4 ( 1 + 3 * 8 ) = 100 nodes
		stubs_per_transit 3
		ts_extra_edges 0
		ss_extra_edges 0

		transit_domains 1
		domains_scale 20
		domains_method pure-random
		domains_connection_prob 1.0
		domains_beta 0.5
		domains_gamma 0.5

		transit_nodes 4
		transit_scale 20
		transit_method pure-random
		transit_connection_prob 0.6
		transit_beta 0.5
		transit_gamma 0.5

		stub_nodes 8
		# the stub scale is ignored by ITM, is computed as fraction
		# of the transit scale... see proc comment below !
		stub_scale 10
		stub_method pure-random
		stub_connection_prob 0.4
		stub_beta 0.5
		stub_gamma 0.5

		# for N level hierarchy
		# assume all levels use same vars
		levels 3
		level_nodes 10
		level_scale 10
		level_method waxman1
		level_connection_prob 0.7
		level_beta 0.2
		level_gamma 0.5
	}
	$self parse_opts
}
	
TG instproc parse_opts { } {
	$self instvar opts opt_info

	while { $opt_info != ""} {
		# parse line by line
                if {![regexp "^\[^\n\]*\n" $opt_info line]} {
                        break  
                }
		# remove the parsed line
                regsub "^\[^\n\]*\n" $opt_info {} opt_info
		# remove leading spaces and tabs using trim
                set line [string trim $line]
		# skip comment lines beginning with #
                if {[regexp "^\[ \t\]*#" $line]} {
                        continue
                }
		# skip empty lines
                if {$line == ""} {
                        continue
                } elseif [regexp {^([^ ]+)[ ]+([^ ]+)$} $line dummy key value] {
                        set opts($key) $value
                } 
	}
}

TG instproc parse_input { args } {
	# remove the list brackets from the args list
        set args [lindex $args 0]
        set len [llength $args]

	$self instvar opts

	for { set i 0 } { $i < $len } { incr i } {
		set key [lindex $args $i]
		regsub {^-} $key {} key
                if {![info exists opts($key)]} {
			puts stderr "unrecognized option $key"
			usage
			return -1
		}
		incr i
		# puts "changing $key from $opts($key) to [lindex $args $i]"
		set opts($key) [lindex $args $i]
	}
	# puts "end of parsing... "
	return 0
}

TG instproc create { args } {
        # remove the list brackets from the args list
        set args [lindex $args 0]
        set len [llength $args]
        # puts "calling create with args $args, len $len"