#/usr/bin/pic2plot -Tps
#
# Pic macros for drawing UML sequence diagrams
#
# (C) Copyright 2004-2005 Diomidis Spinellis.
#
# Permission to use, copy, and distribute this software and its
# documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appear in all copies and that
# both that copyright notice and this permission notice appear in
# supporting documentation.
#
# THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
# WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
# MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
#
# $Id$
#


# Default parameters (can be redefined)

# Spacing between messages
spacing = 0.25;
# Active box width
awid = .1;
# Box height
boxht = 0.3;
# Commend folding
corner_fold=awid
# Comment distance
define comment_default_move {up 0.25 right 0.25};
# Comment height
comment_default_ht=0.5;
# Comment width
comment_default_wid=1;
# Underline object name
underline=1;

# Create a new object(name,label)
define object {
	$1: box $2; move;
	# Could also underline text with \mk\ul\ul\ul...\rt
	if (underline) then {
		line from $1.w + (.1, -.07) to $1.e + (-.1, -.07);
	}
	move to $1.e;
	move right;
	# Active is the level of activations of the object
	# 0 : inactive : draw thin line swimlane
	# 1 : active : draw thick swimlane
	# > 1: nested : draw nested swimlane
	active_$1 = 0;
	lifestart_$1 = $1.s.y;
}

# Create a new external actor(name,label)
define actor {
	$1: [
		XSEQC: circle rad 0.06;
		XSEQL: line from XSEQC.s down .12;
		line from XSEQL.start - (.15,.02) to XSEQL.start + (.15,-.02);
		XSEQL1: line from XSEQL.end left .08 down .15;
		XSEQL2: line from XSEQL.end right .08 down .15;
		line at XSEQC.n invis "" "" "" $2;
	]
	move to $1.e;
	move right;
	active_$1 = 0;
	lifestart_$1 = $1.s.y - .05;
}

# Create a new placeholder object(name)
define placeholder_object {
	$1: box invisible;
	move;
	move to $1.e;
	move right;
	active_$1 = 0;
	lifestart_$1 = $1.s.y;
}

define pobject {
	placeholder_object($1);
}

define extend_lifeline {
	if (active_$1 > 0) then {
                # draw the left edges of the boxes
		move to ($1.x - awid/2, Here.y);
		for level = 1 to active_$1 do {
			line from (Here.x, lifestart_$1) to Here;
			move right awid/2
		}

                # draw the right edge of the innermost box
		move right awid/2;
		line from (Here.x, lifestart_$1) to Here;
	} else {
		line from ($1.x, lifestart_$1) to ($1.x, Here.y) dashed;
	}
	lifestart_$1 = Here.y;
}

# complete(name)
# Complete the lifeline of the object with the given name
define complete {
	extend_lifeline($1)
	if (active_$1) then {
		# draw bottom of all active boxes
		line right ((active_$1 + 1) * awid/2) from ($1.x - awid/2, Here.y);
	}
}

# Draw a message(from_object,to_object,label)
define message {
	down;
	move spacing;
	# Adjust so that lines and arrows do not fall into the
	# active box.  Should be .5, but the arrow heads tend to
	# overshoot.
	if ($1.x <= $2.x) then {
		off_from = awid * .6;
		off_to = -awid * .6;
	} else {
		off_from = -awid * .6;
		off_to = awid * .6;
	}

        # add half a box width for each level of nesting
        if (active_$1 > 1) then {
                off_from = off_from + (active_$1 - 1) * awid/2;
        }

        # add half a box width for each level of nesting
        if (active_$2 > 1) then {
                off_to = off_to + (active_$2 - 1) * awid/2;
        }

	if ($1.x == $2.x) then {
		arrow from ($1.x + off_from, Here.y) right then down .25 then left $3 ljust " " " ";
	} else {
		arrow from ($1.x + off_from, Here.y) to ($2.x + off_to, Here.y) $3 " ";
	}
}

# Display a lifeline constraint(object,label)
define lifeline_constraint {
        off_from = awid;
        # add half a box width for each level of nesting
        if (active_$1 > 1) then {
                off_from = off_from + (active_$1 - 1) * awid/2;
        }

	box at ($1.x + off_from, Here.y) invis $2 ljust " " ;
}

define lconstraint {
	lifeline_constraint($1,$2);
}

# Display an object constraint(label)
# for the last object drawn
define object_constraint {
	{ box invis with .s at last box .nw $1 ljust; }
}

define oconstraint {
	object_constraint($1);
}

# Draw a creation message(from_object,to_object,object_label)
define create_message {
	down;
	move spacing;
	if ($1.x <= $2.x) then {
		off_from = awid * .6;
		off_to = -boxwid * .51;
	} else {
		off_from = -awid * .6;
		off_to = boxwid * .51;
	}

        # add half a box width for each level of nesting
        if (active_$1 > 1) then {
                off_from = off_from + (active_$1 - 1) * awid/2;
        }

	# See comment in destroy_message
	XSEQA: arrow from ($1.x + off_from, Here.y) to ($2.x + off_to, Here.y) "«create»" " ";
	if ($1.x <= $2.x) then {
		{ XSEQB: box $3 with .w at XSEQA.end; }
	} else {
		{ XSEQB: box $3 with .e at XSEQA.end; }
	}
	{
		line from XSEQB.w + (.1, -.07) to XSEQB.e + (-.1, -.07);
	}
	lifestart_$2 = XSEQB.s.y;
	move (spacing + boxht) / 2;
}

define cmessage {
	create_message($1,$2,$3);
}

# Draw an X for a given object
define drawx {
	{
	line from($1.x - awid, lifestart_$1 - awid) to ($1.x + awid, lifestart_$1 + awid);
	line from($1.x - awid, lifestart_$1 + awid) to ($1.x + awid, lifestart_$1 - awid);
	}
}

# Draw a destroy message(from_object,to_object)
define destroy_message {
	down;
	move spacing;
	# The troff code is \(Fo \(Fc
	# The groff code is also \[Fo] \[Fc]
	# The pic2plot code is \Fo \Fc
	# See http://www.delorie.com/gnu/docs/plotutils/plotutils_71.html
	# To stay compatible with all we have to hardcode the characters
	message($1,$2,"«destroy»");
	complete($2);
	drawx($2);
}

define dmessage {
	destroy_message($1,$2);
}

# An object deletes itself: delete(object)
define delete {
	complete($1);
	lifestart_$1 = lifestart_$1 - awid;
	drawx($1);
}

# Draw a message return(from_object,to_object,label)
define return_message {
	down;
	move spacing;
	# See comment in message
	if ($1.x <= $2.x) then {
		off_from = awid * .6;
		off_to = -awid * .6;
	} else {
		off_from = -awid * .6;
		off_to = awid * .6;
	}

        # add half a box width for each level of nesting
        if (active_$1 > 1) then {
                off_from = off_from + (active_$1 - 1) * awid/2;
        }

        # add half a box width for each level of nesting
        if (active_$2 > 1) then {
                off_to = off_to + (active_$2 - 1) * awid/2;
        }

	arrow from  ($1.x + off_from, Here.y) to ($2.x + off_to, Here.y) dashed $3 " ";
}

define rmessage {
	return_message($1,$2,$3);
}

# Object becomes active
# Can be nested to show recursion
define active {
	extend_lifeline($1);
	# draw top of new active box
	line right awid from ($1.x + (active_$1 - 1) * awid/2, Here.y);
	active_$1 = active_$1 + 1;
}

# Object becomes inactive
# Can be nested to show recursion
define inactive {
	extend_lifeline($1);
	active_$1 = active_$1 - 1;
	# draw bottom of innermost active box
	line right awid from ($1.x + (active_$1 - 1) * awid/2, Here.y);
}

# Time step
# Useful at the beginning and the end
# to show object states
define step {
	down;
	move spacing;
}

# Switch to asynchronous messages
define async {
	arrowhead = 0;
	arrowwid = arrowwid * 2;
}

# Switch to synchronous messages
define sync {
	arrowhead = 1;
	arrowwid = arrowwid / 2;
}

# same as lifeline_constraint, but Text and empty string are exchanged.
define lconstraint_below{
        off_from = awid;
        # add half a box width for each level of nesting
        if (active_$1 > 1) then {
                off_from = off_from + (active_$1 - 1) * awid/2;
        }

	box at ($1.x + off_from, Here.y) invis "" $2 ljust;
}

# begin_frame(left_object,name,label_text);
define begin_frame {
	# The lifeline will be cut here
	extend_lifeline($1);
	# draw the frame-label
	$2: box $3 invis with .n at ($1.x, Here.y);
	d = $2.e.y - $2.se.y;
	line from $2.ne to $2.e then down d left d then to $2.sw;
	# continue the lifeline below the frame-label
	move to $2.s;
	lifestart_$1 = Here.y;
}

# end_frame(right_object,name);
define end_frame {
	# dummy-box for the lower right corner:
	box invis "" with .s at ($1.x, Here.y);
	# draw the frame
	frame_wid = last box.se.x - $2.nw.x
	frame_ht = - last box.se.y + $2.nw.y
	box with .nw at $2.nw wid frame_wid ht frame_ht;
	# restore Here.y
	move to last box.s;
}

# comment(object,[name],[line_movement], [box_size] text);
define comment {
	old_y = Here.y
	# draw the first connecting line, at which's end the box wil be positioned
	move to ($1.x, Here.y)
	if "$3" == "" then {
		line comment_default_move() dashed;
	} else {
		line $3 dashed;
	}

	# draw the box, use comment_default_xx if no explicit
	# size is given together with the text in parameter 4
	old_boxht=boxht;
	old_boxwid=boxwid;
	boxht=comment_default_ht;
	boxwid=comment_default_wid;
	if "$2" == "" then {
		box invis $4;
	} else {
		$2: box invis $4;
	}
	boxht=old_boxht;
	boxwid=old_boxwid;

	# draw the frame of the comment
	line from       last box.nw \
		to          last box.ne - (corner_fold, 0) \
		then to last box.ne - (0, corner_fold) \
		then to last box.se \
		then to last box.sw \
		then to last box.nw ;
	line from       last box.ne - (corner_fold, 0) \
		to          last box.ne - (corner_fold, corner_fold) \
		then to last box.ne - (0, corner_fold) ;

	# restore Here.y
	move to ($1.x, old_y)
}

# connect_to_comment(object,name);
define connect_to_comment {
	old_y = Here.y
	# start at the object
	move to ($1.x, Here.y)
	# find the best connection-point of the comment to use as line-end
	if $1.x < $2.w.x then {
		line to $2.w dashed;
	} else {
		if $1.x > $2.e.x then {
			line to $2.e dashed;
		} else {
			if Here.y < $2.s.y then {
				line to $2.s dashed;
			} else {
				if Here.y > $2.n.y then {
					line to $2.n dashed;
				}
			}
		}
	}
	# restore Here.y
	move to ($1.x, old_y)
}