Automatically power down the projector after 15 minutes of Plex inactivity

projector/launchd/com.uberzach.projector.off.plist

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>UserName</key>
+	<string>tv</string>
+	<key>LimitLoadToHosts</key>
+	<array>
+		<string>heady.uberzach.com</string>
+	</array>
+	<key>RunAtLoad</key>
+	<true/>
+	<key>Label</key>
+	<string>com.uberzach.projector.off</string>
+	<key>KeepAlive</key>
+	<dict>
+		<key>NetworkState</key>
+		<true/>
+	</dict>
+	<key>ProgramArguments</key>
+	<array>
+		<string>/Users/tv/bin/video/projector/off.pl</string>
+	</array>
+</dict>
+</plist>

projector/off.pl

@@ -0,0 +1,133 @@
+#!/usr/bin/perl
+use strict;
+use warnings;
+use POSIX qw(ceil floor);
+use File::Temp qw( tempfile );
+
+# Prototypes
+sub mtime($);
+
+# Config
+my $TIMEOUT   = 900;
+my $COUNTDOWN = 300;
+
+# App config
+my $DELAY    = 60;
+my $TEMP_DIR = `getconf DARWIN_USER_TEMP_DIR`;
+chomp($TEMP_DIR);
+my $DATA_DIR = $TEMP_DIR . '/plexMonitor';
+
+# Debug
+my $DEBUG = 0;
+if ($ENV{'DEBUG'}) {
+	$DEBUG = 1;
+}
+
+# Sanity check
+if (!-d $DATA_DIR) {
+	die("Bad config\n");
+}
+
+# State
+my $state      = 'INIT';
+my $stateLast  = $state;
+my $updateLast = 0;
+my $projector  = 0;
+
+# Loop forever
+while (1) {
+
+	# Monitor the GUI and PLAYING files for changes only
+	{
+		my $mtime = mtime($DATA_DIR . '/PLAYING');
+		if ($mtime > $updateLast) {
+			$updateLast = $mtime;
+		}
+		$mtime = mtime($DATA_DIR . '/GUI');
+		if ($mtime > $updateLast) {
+			$updateLast = $mtime;
+		}
+	}
+
+	# Monitor the PROJECTOR file for state only
+	{
+		$projector = 0;
+		my $fh;
+		open($fh, $DATA_DIR . '/PROJECTOR')
+		  or die("Unable to open PROJECTOR\n");
+		my $text = <$fh>;
+		close($fh);
+		if ($text =~ /1/) {
+			$projector = 1;
+		}
+		if ($DEBUG) {
+			print STDERR 'Projector: ' . $projector . "\n";
+		}
+	}
+
+	# Calculate the new state
+	my $stateLast       = $state;
+	my $timeSinceUpdate = time() - $updateLast;
+	if ($DEBUG) {
+		print STDERR 'Time since update: ' . $timeSinceUpdate . "\n";
+	}
+	if ($state eq 'INIT') {
+		$state = 'OFF';
+		if ($projector) {
+			$state = 'ON';
+		}
+	} elsif ($projector) {
+		if ($timeSinceUpdate > $TIMEOUT + $COUNTDOWN) {
+			$state = 'OFF';
+		} elsif ($timeSinceUpdate > $TIMEOUT) {
+			$state = 'COUNTDOWN';
+		}
+	} else {
+		if ($timeSinceUpdate < $TIMEOUT) {
+			$state = 'ON';
+		}
+	}
+
+	# If the state changed, do something about if
+	if ($state ne $stateLast) {
+		if ($DEBUG) {
+			print STDERR 'State change: ' . $stateLast . ' => ' . $state . "\n";
+		}
+		if ($state eq 'OFF') {
+
+			# Turn off the projector
+			my ($fh, $tmp) = tempfile($DATA_DIR . '/PROJECTOR_CMD.XXXXXXXX', 'UNLINK' => 0);
+			print $fh "OFF\n";
+			close($fh);
+			rename($tmp, $DATA_DIR . '/PROJECTOR_CMD');
+		} elsif ($state eq 'ON') {
+
+			# Do nothing, at least for the moment
+		}
+
+	}
+
+	# Always announce a pending shutdown
+	if ($state eq 'COUNTDOWN') {
+		my $timeLeft = ($TIMEOUT + $COUNTDOWN) - $timeSinceUpdate;
+		$timeLeft = ceil($timeLeft / 60);
+
+		my $plural = 's';
+		if ($timeLeft != 1) {
+			$plural = '';
+		}
+		system('say', 'Projector powerdown in about ' . $timeLeft . ' minute' . $plural);
+	}
+
+	# Wait and loop
+	sleep($DELAY);
+}
+
+sub mtime($) {
+	my ($file) = @_;
+	my $mtime = 0;
+	if (-r $file) {
+		(undef(), undef(), undef(), undef(), undef(), undef(), undef(), undef(), undef(), $mtime, undef(), undef(), undef()) = stat($file);
+	}
+	return $mtime;
+}