#!/usr/bin/perl -w
#
# manage a window of screen info
# on a LCD display
#
#
# Original Example/Demo Code
# --------------------------
#	http://www.Linux-1U.net/LCD/get_kb_data.lcd.pl
#
# Keyboard ScanCodes
# ------------------
#	http://www.win.tue.nl/~aeb/linux/kbd/ 	Linux Keyboard and Console HowTO
#	http://ibiblio.org/gferg/ldp/Console-Programming-HOWTO/a321.html
#	http://www.geocities.com/SiliconValley/Park/7113/GameLib/lowLevelKeyboardDriver.html
#	http://www.geocities.com/SiliconValley/Park/7113/GameLib/writeKeyboardDriver.html
#
#	http://www.execpc.com/~geezer/osd/kbd/	( BIOS level )
#	http://www.nondot.org/sabre/os/files/HCI/KeyboardFAQ.txt ( bios level )
#	http://www-users.cs.umn.edu/~arashid/cached/IntroductiontoKeyboardHandlers.htm
#
#
# Keyboard handler
# ---------------
#	http://www.linuxdoc.org/LDP/lkmpg/node25.html
#
#
# Additional Docs for Reading a key from the kb
# ---------------------------------------------
#	http://theoryx5.uwinnipeg.ca/CPAN/perl/pod/perlfaq5/How_can_I_read_a_single_character_from_a_file_From_the_keyboard_.html
#	http://www.rocketaware.com/perl/perlfaq5/How_can_I_read_a_single_characte.htm
#
#
# Read Characters from the regular ps/2 keyboard and display on screen ... ( LCD )
#	- write to the LCD port instead of the stdout screen
#
#
# 01-Dec-01 amo Date-of-Birth -- not too bad for 5 minutes work ( proof of concept )
# 17-Sept-02 srs Reinvtented as a LCD controller
#
# Copyright C2002
# License is the same as the Apache Web Server licence, look it up.
# (for now anyway)
#

############################## General Setup ####################
use strict;
require Term::ReadKey;
use Term::ReadKey;

# GLOBALS to CONFIGURE
# which serial port is the display attached to
#my ( $SERIALPORT ) = "/dev/ttyS0";
my ( $SERIALPORT ) = "/dev/ttyS1";
my($Banner) = "Linux 1RU";  # line #1 - undef or set to "" to not have it
my($RefreshTimeout) = 10; # time to wait to refresh (seconds,-1 for no-refresh)
my($clearOnExit) = 0; #clear the LCD when this program exits?
my($debug) = 1; # 2 is more verbose 0 is none, 1 is standard 

# GLOBALS 
my($lcd_cmd,$lcd_cls,$lcd_gotoline1,$lcd_gotoline2,$lcd_numlines,$lcd_numcols);
my($lcd_type) = "ituner";
my($lcd_input); # if this is defined, set to a serial port for entry
		# and "kbd" events will be processed from it
$| = 1;		# force a flush after our every print

# window globals
my(@window) = ();
my($winpos,$winlen);


##############################  The Code....  ####################
# setup the input and LCD
sub setup {
    # output LCD
    if ($lcd_type =~ /bpi-216/i) {
	system ( "stty 9600 <$SERIALPORT" );
	open ( LCDOUT, "> $SERIALPORT") or die "could not open $SERIALPORT\n";
	$lcd_cmd = "\xFE";	# general command prefix
	$lcd_cls = $lcd_cmd."\x01"	; 	# clear display
	$lcd_gotoline1 = $lcd_cmd."\x02".$lcd_cmd."\xEF" ;
	$lcd_gotoline2 = $lcd_cmd."\xC0";
	$lcd_numlines = 2;
	$lcd_numcols = 16;
    } elsif ($lcd_type =~ /ituner/i || $lcd_type =~ /lk202-25/) {
	system ( "stty 19200 <$SERIALPORT" );
	open ( LCDOUT, "> $SERIALPORT") or die "could not open $SERIALPORT\n";
	$lcd_cmd = "";	                # general command prefix (not used)
	$lcd_cls = "\x0c"	; 	# clear display
	$lcd_gotoline1 = "\xfe\x48" ;
	$lcd_gotoline2 = $lcd_gotoline1."\x0a";
	$lcd_numlines = 2;
	$lcd_numcols = 20;
#	use IPC::Open2;
#	open2(\*LCDIN, LCDOUT, "cat $SERIALPORT 2>&1");
	
    } else {
	print STDERR "Unknown lcd type!!! ($lcd_type).  Bailing.\n";
	exit 1;
    }

    # input LCD (if present)
    if ($lcd_type =~ /bpi-216/i) {
	# no input
#	open (LCDIN, "< /tmp/testinput"); # not really useful
    } elsif ($lcd_type =~ /ituner/i || $lcd_type =~ /lk202-25/) {
        if (not defined $lcd_input) {$lcd_input = $SERIALPORT;}
	system ( "stty 19200 <$SERIALPORT" );
	open ( LCDIN, "< $SERIALPORT") or die "could not open $SERIALPORT\n";
    }

    # turn on flushing
    select((select(LCDOUT), $|=1)[0]);
    print LCDOUT "$lcd_cls";

    # setup window abstraction
    wm_setup();
}

	

# close up shop
sub teardown {
    if ($clearOnExit) {printf LCDOUT "$lcd_cls";}
    close(LCDOUT);
    close(LCDIN) if ($lcd_input);
    ReadMode 0; # Reset tty mode before exiting
}


# get input chars (for now - random info from 
sub fill_window {
    # title
    wm_append($Banner) if (defined $Banner and ((length $Banner) > 0));

    # Network info
    my  ( $host ) = `hostname`;
    chomp ( $host );
    wm_append("net $host");

    my ( @ipaddr ) = split ( /:/, `ifconfig -v | grep -i "inet addr" | grep -v 127.0.0 ` );

    if ($#ipaddr>0) {
	my ( $ip ) = $ipaddr[1];
	chomp ( $ip );
	$ip =~ s/\s.*//; # nuke end
	wm_append("$ip");
	my($mask) = $ipaddr[3];
	chomp ( $mask );
	$mask =~ s/\s.*//; # nuke end
	wm_append(" $mask");
    }

    # 2nd interface (untested)
    if ($#ipaddr >= 6) {
        my ( $ip ) = $ipaddr[4];
	chomp ( $ip );
	$ip =~ s/\s.*//; # nuke end
	wm_append("$ip");
	my($mask) = $ipaddr[6];
	chomp ( $mask );
	$mask =~ s/\s.*//; # nuke end
	wm_append(" $mask");
    }
    

    my(@route) = split (/\s+/,`route -n|grep '^0.0.0.0'`);
    if ($#route > 0) {
	chomp($route[1]);
	wm_append(">" . $route[1]);
    } else {
	wm_append(">No network is stetup(!)");
    }

    # load info
    my($upinfo) =`uptime`;
    $upinfo =~ s/\s\s/ /g; # nuke extra space
    $upinfo =~ s/^\s+//;   # nuke inital space
    $upinfo =~ m/(.*),/;   # grab time/uptime
    wm_append($1);

    $upinfo =~ m/\s*(\d*) users/;
    wm_append("Users " . $1 . " " . `users`);

    $upinfo =~ s/\s*load average:/Load/;
    $upinfo =~ m/(Load.*)/; 
    wm_append ($1);

    wm_append("PS:");
    my($line);
    foreach $line (`ps -eo '%cpu %mem args' --sort='-%cpu,-%mem'`)  {
	chomp($line);
	$line =~ s/^\s+//; # kill initial space(s)
	$line =~ s/\s\s+/ /g; # kill extra space(s)
	wm_append($line);
    }

}

sub init_data {
    fill_window();
}

sub refresh_data {
    wm_clear();
    fill_window();
}

# send output to LCD, 2 lines, presenting the 2 lines in the window at winpos
sub output {
    if ($debug>1) {
	print "OUTPUT, position $winpos, window is:\n";
	my($line);
	foreach $line (@window) {
	    print "$line\n";
	}
    }

    my($line1) = wm_get($winpos);
    my($line2) = wm_get($winpos+1);
    print "L1: $line1!\n" if ($debug and defined $line1);
    print "L2: $line2!\n" if ($debug and defined $line2);

    my($oldfh) = select LCDOUT;

    if (defined $line1 && ($line1 ne "")) {
	print "$lcd_gotoline1";
	print substr $line1, 0, $lcd_numcols;
	my($len) = length $line1;
	my ($diff) = $lcd_numcols - $len;
	if ($diff>0) {print " " x $diff;}
    }
    if (defined $line2 && ($line2 ne "")) {
	print "$lcd_gotoline2";
	print substr $line2, 0, $lcd_numcols; 
	my($len) = length $line2;
	my ($diff) = $lcd_numcols - $len;
	if ($diff>0) {print " " x $diff;}
    }
    select $oldfh;
    
}

# read one "character" (i.e. keypress including multi-char esc codes)
# and call a processing routine on it, then return it.
# This should use a keymap of functions like ReadLine.
# in reality it is brute force.
# return vals:
# 0 - exit
# 1 - normal
sub process_kbd {
    my($key);
    ReadMode 3; 
#     while (1) {
#         $key = ReadKey(($RefreshTimeout>0) ? $RefreshTimeout : 0);
# 	if ((not defined $key) and ($RefreshTimeout>0)) {  
#             # timed out, so do a refresh
# 	    print "Refreshing\n" if ($debug>1);
# 	    &refresh_data;
# 	} else {
# 	    last;
# 	}
#     }
    $key = ReadKey(-1);
    return 1 if (not defined $key);

    print "Got key $key\n" if ($debug);
    return process_char($key);
}

sub process_char {
    my($key) = @_;
    my($retval)=1;

    # Escape chars have multiple characters to follow
    if ($key =~ /[0-9]/) { &wm_goto($key);}
    elsif ($key =~ /q/i) { $retval = 0;}
    elsif ($key =~ /r/i) { refresh_data();}
    elsif ($key =~ //) { refresh_data();}
    elsif ($key =~ /a/i) { alvin_example();}
    elsif ($key =~ /n/i) { &wm_search("net");} # goto net
    elsif ($key =~ /p/i) { &wm_search("ps");} # goto PS
    elsif ($key =~ /t/i) { type_mode();} # fancy
    elsif ($key =~ /[A-Za-z>!@]/) { &wm_search($key);} # if not special, search
    elsif ($key eq "") {$retval = 0;}
    elsif ($key eq "") {
	print " multipart...." if ($debug);
	# this is a hack....
	# Quickly read in the rest, unbuffered, since we assume all is there
	# could maybe fail over slow connections or something.
	my($keystring) = "";
	my($newkey)="";
	do {
	    $keystring .= $newkey;
	    $newkey = ReadKey(-1); # nonblocking read
	} while (defined $newkey);
	print "String is $keystring!\n" if ($debug>1);
	if ($keystring eq "[A") {&wm_up;        # up arrow
        } elsif ($keystring eq "[B") {&wm_down; # down arrow
	} elsif ($keystring eq "[C") {&wm_up;   # right arrow
	} elsif ($keystring eq "[D") {&wm_down; # left arrow
	} elsif ($keystring eq "[1~") {&wm_top;  # HOME
	} elsif ($keystring eq "[4~") {&wm_bot; # END
	} elsif ($keystring eq "[[A") {&wm_down; # F1
        } elsif ($keystring eq "[6~") {&do_screendown; # PageDown
        } elsif ($keystring eq "[5~") {&do_screenup; # PageUp
        }
    }
    return $retval;
}

sub process_lcd_char {
    my($key) = @_;
    my($retval)=1;
    if ($lcd_type =~ /ituner/i) {
	if ($key eq "O") { refresh_data();}  
	elsif ($key eq "D") {&wm_up;}
	elsif ($key eq "J") {&wm_down;}
	elsif ($key eq "E") {$retval = 0;}
	else {print "No function for that key...($key)\n";}
    } else {
       # full lk202-25/)
	print "No function for that key...($key)\n";
    }
    return $retval;
}

sub process_lcd {
    my($key,$retval);
    print "reading...\n";
    ReadMode(3, \*LCDIN);
    $key = ReadKey(-1, \*LCDIN);

    if (defined $key) {
        print "Got LCD $key\n" if ($debug);
	$retval = process_lcd_char($key);
    } else {
       $retval = 1;
    }
    return $retval;
}

############################## Sample Functions #################### 
# Functions can be called in two ways - bind them to a keystroke
# in which case you add a hook to process_kbd
# or selected out of an LCD controller - in which case process_lcd
# gets the hook.
sub alvin_example {
    # append 2 lines at the bottom of the window
    wm_append("Provided by...");
    wm_append("Alvin & Steve");
    wm_bot(); # go to the bottom of the window
}

sub do_screendown {
    for(my($i)=0; $i<$lcd_numlines; $i++) {
	wm_down();
    }
}

sub do_screenup {
    for(my($i)=0; $i<$lcd_numlines; $i++) {
	wm_up();
    }
}

sub type_mode {
    my($key)="";
    my($buf)="";
    print "Type a one line message which will appear at end of window\n";
    do {
	if ($key ne "" and $key ne "") {
	    $buf .= $key;
	} else {
	    my($len) = length $buf;
	    if ($len>0) {
		$buf = substr($buf, 0, $len-1);
	    }
	}
	print $key;
	$key=ReadKey();
    } while (defined $key and $key ne "\n");

    &wm_bot; # go close to the bottom
    my($line);
    foreach $line (split /\n/, $buf) {
	print "append $line\n" if ($debug>1);
	wm_append($line);
    }
    # go to top of new input/close to it anyway
    do_screendown();
    print "Back to main read loop...\n";
}

# Windowing subs
sub wm_setup {$winpos=0; $winlen = $lcd_numlines;}
sub wm_clear { @window = ();}
sub wm_top {$winpos = 0;}
sub wm_bot {$winpos = $#window; &wm_bounds;}
sub wm_goto {$winpos = @_; &wm_bounds;}
sub wm_size {return $#window;}
sub wm_up {$winpos--; &wm_bounds;}
sub wm_down {$winpos++; &wm_bounds;}
sub wm_bounds {
    if ($winpos < 0) {$winpos = 0;} 
    if ($winpos > $#window-($winlen-1)) {$winpos = $#window-($winlen-1);}
}
sub wm_append {push @window, @_;}
sub wm_getpos {return $winpos;}
# find a line starrting with the arg string (ignore case)
sub wm_search {
    my($find) = @_;
    for(my($i)=0; $i<$#window; $i++) {
	if ($window[$i] =~ m/^$find/i) {
	    $winpos = $i;
	    &wm_bounds;
	    return;
	}
    }
    &wm_bot;
}
sub wm_get {
    my($line) = @_; 
    if (defined $line) {return $window[$line];}
    return $window[$winpos];
}

# Main
sub main {
    # process args
    while ($#ARGV>=0) {
	if ($ARGV[0] =~ m/-type/i) {
	    # get type
	    shift @ARGV;
	    $lcd_type = $ARGV[0];
	    print "Set type to $lcd_type\n" if ($debug);
	} elsif ($ARGV[0] =~ m/-in/i) {
	    shift @ARGV;
	    $lcd_input = $ARGV[0];
	    print "Set input to $lcd_input\n" if ($debug);
	} else {
	    print qq@I don't understand "@ . $ARGV[0] . qq@"\n@;
	    print "usage: [-type {bpi-216|ituner|lk202-25}] [-in <device>]\n";
	    exit;
	}
	shift @ARGV;
    }

    setup;

    print "Welcome to the LCD controller...\n";
    # setup the window buffer
    init_data;
    
    # process keystrokes and redisplay the window
    print qq@Type commands to navigate:
ARROWS - move forward and back
HOME - goto top;   END - goto end
PageDown/Up - move by a page
n - goto network info
p - goto PS info
# - goto line # 
a - alvin demo
t - typing mode
^L or r - refresh info
q or ^D - quit
OTHER KEY - search for a line starting with that key
@;
    my($result)=1;
    do {
	output;
	$result = process_kbd;
	if (defined $lcd_input) {
           $result = $result && &process_lcd();
;
        }
        sleep(1); # gross but dont be so busy
    } while ($result>0);
    print "\n";
    teardown;
}

# and run....
main;
exit;