From 0eb7f2ec95c831bc92bbe0ac9aa2c4da09b5a3a3 Mon Sep 17 00:00:00 2001
From: Matt Birkholz <puck@birchwood-abbey.net>
Date: Sat, 16 Jan 2016 17:47:51 -0700
Subject: [PATCH] Add MONITOR-WORLD Edwin command displaying an animated
 world-report.

---
 src/edwin/decls.scm         |   1 +
 src/edwin/edwin.ldr         |   1 +
 src/edwin/edwin.pkg         |   1 +
 src/edwin/world-monitor.scm | 118 ++++++++++++++++++++++++++++++++++++
 4 files changed, 121 insertions(+)
 create mode 100644 src/edwin/world-monitor.scm

diff --git a/src/edwin/decls.scm b/src/edwin/decls.scm
index acf41a14f..bbf5e7079 100644
--- a/src/edwin/decls.scm
+++ b/src/edwin/decls.scm
@@ -236,6 +236,7 @@ USA.
 		"winout"
 		"xcom"
 		"win32com"
+		"world-monitor"
 		"xmodef")))
   (for-each sf-class
 	    '("comwin"
diff --git a/src/edwin/edwin.ldr b/src/edwin/edwin.ldr
index 49d3a1493..dd4f32fcf 100644
--- a/src/edwin/edwin.ldr
+++ b/src/edwin/edwin.ldr
@@ -268,6 +268,7 @@ USA.
 				  (->environment '(EDWIN BOCHSER)))
 	|#
 	(load "notify" environment)
+	(load "world-monitor" environment)
 	(if (access *external-doc-strings?* environment)
 	    (begin
 	      (set! (access *external-doc-strings?* environment) false)
diff --git a/src/edwin/edwin.pkg b/src/edwin/edwin.pkg
index 60e77d33c..711d69f3e 100644
--- a/src/edwin/edwin.pkg
+++ b/src/edwin/edwin.pkg
@@ -99,6 +99,7 @@ USA.
 	 "outline"			; outline minor mode
 	 "sort"				; sorting commands
 	 "webster"			; access a Webster server
+	 "world-monitor"
 	 )
 
   (parent ())
diff --git a/src/edwin/world-monitor.scm b/src/edwin/world-monitor.scm
new file mode 100644
index 000000000..dac34edad
--- /dev/null
+++ b/src/edwin/world-monitor.scm
@@ -0,0 +1,118 @@
+#| -*-Scheme-*-
+
+Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
+    1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
+    2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016
+    Massachusetts Institute of Technology
+
+This file is part of MIT/GNU Scheme.
+
+MIT/GNU Scheme is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at
+your option) any later version.
+
+MIT/GNU Scheme is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with MIT/GNU Scheme; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301,
+USA.
+
+|#
+
+;;;; Create a *World* buffer containing the world report.
+
+(declare (usual-integrations))
+
+(define-command monitor-world
+  "Find or create a buffer named *World*, insert a world report into
+it, and spawn a thread to update it after every
+\\[world-monitor-sleep] seconds."
+  ()
+  (lambda ()
+    (let* ((buffer (find-or-create-buffer "*World*"))
+	   (thread (buffer-get buffer 'WORLD-MONITOR #f)))
+      (if (not thread)
+	  (start-world-monitor buffer))
+      (pop-up-buffer buffer #f))))
+
+(define-variable world-monitor-sleep
+  "Number of seconds the world monitor should sleep between reports."
+  1.
+  (lambda (object)
+    (and (flo:flonum? object)
+	 (flo:< .09 object))))
+
+(define (start-world-monitor buffer)
+  (set-buffer-major-mode! buffer (ref-mode-object read-only))
+  (let ((registration #f)
+	(report #f)
+	(thread-flags (list (cons (current-thread) "Edwin"))))
+
+    (define (new-report)
+      (with-output-to-string
+	(lambda () (world-report (current-output-port) thread-flags))))
+
+    (define (sleep)
+      (sleep-current-thread
+       (flo:round->exact
+	(flo:* 1000. (ref-variable world-monitor-sleep)))))
+
+    (let ((monitor
+	   (create-thread editor-thread-root-continuation
+	     (named-lambda (monitor-world)
+	       (let loop ()
+		 (sleep)
+		 (if (buffer-alive? buffer)
+		     (begin
+		       (if registration
+			   (begin
+			     (set! report (new-report))
+			     (inferior-thread-output! registration)))
+		       (loop))
+		     (begin
+		       (if registration
+			   (deregister-inferior-thread! registration))
+		       (set! registration #f)
+		       (exit-current-thread #t))))))))
+
+      (buffer-put! buffer 'WORLD-MONITOR monitor)
+      (update-world-monitor! buffer (new-report))
+      (set! registration
+	    (register-inferior-thread!
+	     monitor (named-lambda (world-monitor-output!)
+		       (update-world-monitor! buffer report)))))))
+
+(define (update-world-monitor! buffer report)
+  (let ((saved-windows
+	 (map (lambda (window)
+		(cons window
+		      (cons (mark-temporary-copy (window-point window))
+			    (window-start-mark window) ;already temporary
+			    )))
+	      (buffer-windows buffer)))
+	(saved-mark (let ((ring (buffer-mark-ring buffer)))
+		      (if (ring-empty? ring)
+			  #f
+			  (mark-temporary-copy (ring-ref ring 0))))))
+    (with-read-only-defeated
+     buffer (lambda ()
+	      (with-group-undo-disabled
+	       (buffer-group buffer)
+	       (lambda ()
+		 (buffer-widen! buffer)
+		 (region-delete! (buffer-region buffer))
+		 (insert-string report (buffer-start buffer))
+		 (buffer-not-modified! buffer)))))
+    (for-each (lambda (item)
+		(let ((window (car item))
+		      (point (cadr item))
+		      (start (cddr item)))
+		  (set-window-point! window point)
+		  (set-window-start-mark! window start 0)))
+	      saved-windows)
+    (if saved-mark (set-buffer-mark! buffer saved-mark))))
\ No newline at end of file
-- 
2.25.1