#!/usr/bin/env ruby
###################  logxp2i -- brent@mbari.org  #######################
#    Copyright (C) 2006 MBARI
#    MBARI Proprietary Information. All rights reserved.
#
#   Log pressure data from a Crystal Engineering Corp. XP2i
#   connected on specified serial port
#
########################################################################

require 'getoptlong'

opts = GetoptLong.new(
  ["--reset", "-r", GetoptLong::NO_ARGUMENT],
  ["--help", "-h",  GetoptLong::NO_ARGUMENT]
)

progName = File.basename $0

def putHelp
      $stderr.puts "\
Log serial data from Crystal XP2i pressure sensor -- 12/11/06 brent@mbari.org
Options:
  --help          #displays this text
  --reset         #reset the gauge before monitoring pressure
                  #(this takes about 30 seconds)

First argument is the name of the serial port to which the pressure
sensor is connected.  Defaults to /dev/xp2i
The logged pressure data (ASCII) is written to stdout.
"
    exit
end

reset=false

opts.each do |opt, arg|
  case opt
  when "--reset"
    reset=true
  else
    putHelp
  end
end

putHelp if ARGV.size > 1
deviceFn = ARGV.size == 0 ? '/dev/xp2i' : ARGV.first

require 'fcntl'
require 'termios'
include ::Termios

def cmd(string, device=$device)
  sleep .05
#  puts(string)
  device.print(string, "\r")
  device.flush
end

def rsp(terminator=nil, device=$device)
  response = terminator ? device.gets(terminator) : device.gets
  response.chop!
#  puts(response.dump)
  response
end

def query(string, terminator=nil, device=$device)
  cmd(string)
  rsp(terminator, device)
end

def purgeInput delay=0.5, device=$device
  purger = Thread.new {nil while(device.getc)}  #throw away any spurious input
  $stdout.flush
  sleep delay
  purger.kill
end

OK='A,0'

open(deviceFn, File::RDWR | File::NONBLOCK) do |device|
 begin
  device.ioctl(0x540c,0)  #TIOCEXCL -- prevent others from opening this device
  device.sync=false
  tio = new_termios()
  tio.iflag = IGNPAR
  tio.cflag = CLOCAL | CS8 | CREAD
  tio.oflag = tio.lflag = 0
  tio.ispeed = tio.ospeed = B9600
  tio.cc[VTIME] = 0
  tio.cc[VMIN] = 1
  device.tcsetattr(TCSANOW, tio)
  device.fcntl(Fcntl::F_SETFL, device.fcntl(Fcntl::F_GETFL,0) & ~File::NONBLOCK)
  $device=device

  puts "#{Time.now} --#{' Reset' if reset} "\
        "XP2i pressure sensor on #{device.path}"
  purgeInput
  if reset
    print "Rcv'd boot signature:  ", query("!RST","\r"), "\n"
    purgeInput 15
  end

  cmd "!NAO"  #be sure to cancel auto-off
  raise "Invalid Response to Auto-Off disable" unless
    rsp.strip == 'NO' and rsp.strip == 'AUTO' and
    rsp.strip == 'OFF' and rsp == OK

  product=query("?SN#").strip  #query product code & serial number
  sn=rsp.strip
  ver=query "?VER"
  puts "Product code #{product}, Serial ##{sn}, Version #{ver}"

  begin
    raise "Invalid Response to Stream Start" if query("!SP1") != OK
    minute = Time.now
    loop {
      begin
        puts rsp
        $stdout.flush
      end while ((now=Time.now) - minute < 60)
      puts minute=now
    }
  ensure
    cmd("!SP0")
    puts "Stopped streaming."
  end
 ensure
   device.ioctl(0x540D,0)  #release device
 end
end