# set your zone if you want to get time in you local time zone. 
# otherwise it will be UTC
Nmea::Config.time_zone = "Tokyo"

# create a serialport to your GPS receiver
# you should know how to open a connection between your GPS device
# mine runs on `9600 baudrate`, `8bit`, `1stop bit`, `none parity`
serialport = SerialPort.new("/dev/cu.your_whatever_device", 9600, 8, 1, SerialPort::NONE)

# you should know about your GPS receiver's update Hz(how often it will update logs 10Hz = 10 times per sec.)
# if you don't know leave it blank.  It will at least update every sec.
gps = Nmea::Gps.new serialport update_hz: 10

# this will be called automatically!!
gps.rmc do |rmc|
  # you will get a sentence object as a parameter
  # for gsv callback, it will be an array containing multiple gsv objects [gsv, gsv, gsv]
  p rmc.raw_sentence_line
  p rmc.raw_data
  p rmc.time
  p rmc.latitude
  p rmc.longitude
  p rmc.heading
  p rmc.date
end
# sentences > https://github.com/github0013/nmea_gps/tree/master/lib/nmea_gps/sentences
# you have a callback on each sentence such as gga, gll ..., 

# built-in error callback (catch errors in the internal thread)
gps.error do |exception|
  p exception.message
  puts exception.backtrace.join "\n"
end

# if you want to receive all ...
gps.all do |sentence, sentence_object|
  p sentence         # such as :gga, :rmc
  p sentence_object  # such as Nmea::Gps::Rmc, [Nmea::Gps::Gsv, Nmea::Gps::Gsv, ...]
end

# start the tracking
gps.track!

# you can also have
# gps.gga do |gga|
#   ..
# end
# gps.gll do |gll|
#   ..
# end
# gps.gsa do |gsa|
#   ..
# end
# gps.vtg do |vtg|
#   ..
# end
# gps.zda do |zda|
#   ..
# end
# 
# this one gets multiple Gsv objects
# gps.gsv do |gsvs|
#   p gsvs.count
#   ..
# end

# do your other works
# ..
# ..
# ..


# you can clear callbacks on the run
gps.clear_rmc # this will stop the call instantly


# you can even start a callback on the run 
gps.gga do |gga|
  p [gga.latitude, gga.longitude]
end

# when you want to stop callbacks, you can call this
# gps.stop!
# then close the connection
# serialport.close