From 81d6f76c7855d3f6d974319ca3620ccea0bed58d Mon Sep 17 00:00:00 2001
From: Renaud Fivet <renaud.fivet@gmail.com>
Date: Wed, 8 Sep 2021 11:05:51 +0800
Subject: [PATCH] Test maze scripts using subroutines instead of stored
 procedures. (Avoid leftover buffers after execution).

---
 blindmaz.cmd | 87 +++++++++++++++++++++++-----------------------------
 floodmaz.cmd | 69 +++++++++++++++++++----------------------
 sharpmaz.cmd | 23 +++++++-------
 3 files changed, 82 insertions(+), 97 deletions(-)

diff --git a/blindmaz.cmd b/blindmaz.cmd
index adb3497..0fb496a 100644
--- a/blindmaz.cmd
+++ b/blindmaz.cmd
@@ -4,13 +4,14 @@
 # either maze.cmd, sharpmaz.cmd or floodmaz.cmd
 execute-file floodmaz.cmd
 
-set %meml $curline	# save entrance location
-set %memc $curcol
-set %x &add %memc 1
-set %y %meml
+set %dotc &asc "•"	# alternatively use "."
+set $curchar %dotc
+set %x &add $curcol 1
+set %y $curline
 end-of-line
 set %stopcol &sub $curcol 1
 
+# X-Y offset for absolute direction: east, south, west, north
 set %DX0 1
 set %DY0 0
 set %DX1 0
@@ -20,53 +21,41 @@ set %DY2 0
 set %DX3 0
 set %DY3 -1
 
-set %dotc &asc "•"	# alternatively use "."
-
-!store peep
-	set %OX &ind &cat "%DX" %nD
-	set %OY &ind &cat "%DY" %nD
-	set %nx &add %x %OX
-	set %ny &add %y %OY
-	set $curline %ny
-	set $curcol %nx
-	!if &or &equ $curchar 32 &equ $curchar %dotc
-		!if &equ $curchar 32
-			set %C %dotc
-		!else
-			set %C &asc " "		# erase when backtracking (or highlight)
-		!endif
-		set %D %nD
-		set $curchar %C
-		set $curline %y
-		set $curcol %x
-		set $curchar %C
-		set %x &add %nx %OX
-		set %y &add %ny %OY
-		set $curline %y
-		set $curcol %x
-		set %res TRUE
-	!else
-		set %res FALSE
-	!endif
-	update-screen
-!endm
-
-set %D 0		# looking EAST
+set %absD 0							# absolute direction: looking EAST
 !while &les %x %stopcol
-	set %nD &mod &add %D 3 4				# Can go left?
-	run peep
-	!if &not %res
-		set %nD %D							# Can go straight?
-		run peep
-		!if &not %res
-			set %nD &mod &add %D 1 4		# Can go right?
-			run peep
-			!if &not %res
-				set %D &mod &add %D 2 4		# Go back!
+# try move on left, right or front
+	set %relD 3						# 3, 0, 1, 2 == left, front, right, back
+	!while &not &equ %relD 2
+		set %newD &mod &add %absD %relD 4
+		set %offX &ind &cat "%DX" %newD
+		set %offY &ind &cat "%DY" %newD
+		set %nx &add %x %offX
+		set %ny &add %y %offY
+		set $curline %ny
+		set $curcol  %nx
+		!if &or &equ $curchar 32 &equ $curchar %dotc
+			!if &equ $curchar 32
+				set %C %dotc
+			!else
+				set %C &asc " "		# erase (or highlight) when backtracking
 			!endif
+			set %absD %newD
+			set $curchar %C
+			set $curline %y
+			set $curcol  %x
+			set $curchar %C
+			set %x &add %nx %offX
+			set %y &add %ny %offY
+			update-screen
+			!goto moveon
 		!endif
-	!endif
+		set %relD &mod &add %relD 1 4
+	!endwhile
+# else turn around
+	set %absD &mod &add %absD 2 4	#	 face back!
+:moveon
 !endwhile
-set $curline %meml
-set $curcol %memc
+
+set $curline %y
+set $curcol  %x
 unmark-buffer
diff --git a/floodmaz.cmd b/floodmaz.cmd
index 5ef43f0..f12b059 100644
--- a/floodmaz.cmd
+++ b/floodmaz.cmd
@@ -1,4 +1,4 @@
-## floodmaz.cmd -- solve maze by painting right wall
+## floodmaz.cmd -- solve maze by painting wall on the right
 
 # 6 set $seed
 # either maze.cmd or sharpmaz.cmd
@@ -8,39 +8,9 @@ set %thisbuf $cbufname
 set %meml $curline
 set %memc $curcol
 
-!store pushxy				# push x y
-	set %x $curcol
-	set %y $curline
-	select-buffer stack
-	beginning-of-file
-	insert-string %x
-	newline
-	insert-string %y
-	newline
-	select-buffer %thisbuf
-!endm
-
-!store popxy				# pop x y
-	select-buffer stack
-	beginning-of-file
-	set %x $line
-1	kill-to-end-of-line
-	set %y $line
-1	kill-to-end-of-line
-	select-buffer %thisbuf
-	set $curline %y
-	set $curcol %x
-!endm
-
-!store probe
-	!if &not &or &equ $curchar %NC &equ $curchar 32
-		run pushxy
-	!endif
-!endm
-
 set $curline 1
 set $curcol 0
-run pushxy	#push stop position
+!gosub pushxy	#push stop position
 set %x 1
 set $curline 4
 set $curcol %x
@@ -51,16 +21,25 @@ set %NC &asc "█"
 	set %cc $curcol
 	set %ll $curline
 	set $curcol &add %cc 1
-	run probe
+	!gosub probe
 	set $curcol &add %cc -1
-	run probe
+	!gosub probe
 	set $curline &add %ll 1
 	set $curcol %cc
-	run probe
+	!gosub probe
 	set $curline &add %ll -1
 	set $curcol %cc
-	run probe
-	run popxy	
+	!gosub probe
+# pop x y
+	select-buffer stack
+	beginning-of-file
+	set %x $line
+1	kill-to-end-of-line
+	set %y $line
+1	kill-to-end-of-line
+	select-buffer %thisbuf
+	set $curline %y
+	set $curcol %x
 !endwhile
 
 set $curline %meml
@@ -70,3 +49,19 @@ unmark-buffer
 select-buffer %thisbuf
 unmark-buffer
 delete-buffer stack
+!return
+
+:probe
+	!if &not &or &equ $curchar %NC &equ $curchar 32
+	:pushxy					# push x y
+		set %x $curcol
+		set %y $curline
+		select-buffer stack
+		beginning-of-file
+		insert-string %x
+		newline
+		insert-string %y
+		newline
+		select-buffer %thisbuf
+	!endif
+!return
diff --git a/sharpmaz.cmd b/sharpmaz.cmd
index b262266..5d0b974 100644
--- a/sharpmaz.cmd
+++ b/sharpmaz.cmd
@@ -15,13 +15,6 @@ set %old $line
 set $line %spaces
 next-line
 
-!store check
-	!if &not &equ $curchar 32
-		set %v &add %v %inc
-	!endif
-	set %inc &tim %inc 2
-!endm
-
 !while &less $curline %el
 	set $curcol 1
 	!while &less $curcol %ec
@@ -29,15 +22,15 @@ next-line
 			set %v 0
 			set %inc 1
 			previous-line
-			run check
+			!gosub check
 			next-line
 			backward-character
-			run check
+			!gosub check
 			2 forward-character
-			run check
+			!gosub check
 			next-line
 			backward-character
-			run check
+			!gosub check
 			previous-line
 			# alternatively use single width "╳╵╴┘╶└─┴╷│┐┤┌├┬┼"
 			set $curchar &asc &mid "╳╹╸┛╺┗━┻╻┃┓┫┏┣┳╋" &add %v 1 1
@@ -51,3 +44,11 @@ beginning-of-file
 set $line %old
 set $curline %meml
 set $curcol %memc
+!return
+
+:check
+	!if &not &equ $curchar 32
+		set %v &add %v %inc
+	!endif
+	set %inc &tim %inc 2
+!return