From 2acb7dcd8226de1cb36695b4b8bffe31131c6a52 Mon Sep 17 00:00:00 2001
From: Will Bradley <bradley.will@gmail.com>
Date: Sat, 6 Jul 2019 20:09:29 -0700
Subject: [PATCH] trying out observer and timers

---
 serial.rb | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/serial.rb b/serial.rb
index 382f036..e4a5b6d 100644
--- a/serial.rb
+++ b/serial.rb
@@ -1,4 +1,6 @@
 require 'rubyserial'
+require 'observer'
+require 'timers'
 
 #
 # User Configs
@@ -17,6 +19,7 @@ parity = :none
 
 @serial = Serial.new device, baud, bits, parity
 @buffer = Queue.new
+@timers = Timers::Group.new
 
 #
 # Convenience function
@@ -49,7 +52,20 @@ def b_open(num)
 	serial_writeln("o #{num}")
 end
 def b_unlock()
+	# Listen for an unlock event; raise an error if not found
+	foo = @timers.after(5) {
+		if @events[:unlocked].changed?
+			print "foo"
+		else
+			print "didn't get an unlock event in time"
+		end
+	}
+	print foo.inspect
+	SerialListener.new(@events[:unlocked],
+		Proc.new{ |value| print "got unlock event #{value}" }
+	)
 	serial_writeln("u")
+	@timers.fire
 end
 def b_lock()
 	serial_writeln("l")
@@ -163,6 +179,7 @@ def parse_in()
 			case sline
 				when /(\d*) unlocked$/ # ends line
 					print ">Door #{$1} unlocked\n"
+					@events[:unlocked].send($1)
 				when /All Doors relocked/
 					print ">All Doors relocked\n"
 				when /Door (\d*) locked$/ # ends line
@@ -282,10 +299,47 @@ def parse_in()
 	end
 end
 
+#
+# Classes
+#
+
+class SerialEvents
+	include Observable
+
+	@oldvalue = nil
+
+	def send(value)
+		if value != @oldvalue
+			changed
+			@oldvalue = value
+			notify_observers(Time.now, value)
+		end
+	end
+
+end
+
+class SerialListener
+	@callback = nil
+
+	def initialize(observable, callback)
+		@callback = callback
+		observable.add_observer(self)
+	end
+
+	def update(time, value)
+		@callback.call(value)
+	end
+end
+
 #
 # Runtime
 #
 
+@events = {
+	unlocked: SerialEvents.new,
+	locked: SerialEvents.new,
+}
+
 puts "> Started threads at #{Time.now}"
 t1 = Thread.new{console_in()}
 t2 = Thread.new{serial_in()}