#!/bin/env python

# TODO - change USNO processing to check if schedule only contains MK and PT antennas

from sys import argv, exit, stdin
from os import system, chdir, getcwd, environ, popen
from os.path import isfile, isdir
from string import replace, strip, split, lower, upper, find
import datetime

program = 'unqueueVex'
version = 0.2
verdate = '20111214'
author  = 'Walter Brisken'

verbose = 1

observTxFile = 'observ.tx'
ccScriptDir = '/export/home/cc/vlba/scripts'
prestartTime = 300	# seconds
poststopTime = 30	# seconds
difxPath = '/home/swc/DiFX-trunk/bin'
difxbinpath = '/users/difx/bin'
linesToShow = 10

# ------------------

def usage():
	print '\n%s ver. %s  %s  %s\n' % (program, version, verdate, author)
	print 'Usage: %s [options] <vexfile1> [vexfile2] ... [ant1] [ant2] ...\n' % argv[0]
	print 'options can be:\n'
	print '  -h or --help       print help info and quit.'
	print '  -v or --verbose    make more verbose.'
	print '  -q or --quiet      make less verbose.'
	print '  -f or --force      proceed without question in some cases.'
	print ''
	print 'One or more vex files can be supplied.  All supplied vex files will'
	print 'be handled separately in the order listed.'
	print ''
	print 'Optional list of antenna codes can be used to restrict which antennas'
	print 'to operate on.  If no antennas are listed, all antennas in the vex'
	print 'file(s) will be assumed.'


mjd0 = datetime.datetime(1858, 11, 17, 0, 0)

def execute(cmd, nostdout=0):
	if verbose > 0:
		print 'About to execute: %s' % cmd
	if nostdout == 0:
		system(cmd)
	else:
		popen(cmd).readlines()

def vexPeek(vexFile):
	
	cmd = '%s/vexpeek %s' % (difxPath, vexFile)
	if verbose > 0:
		print 'Executing command: %s' % cmd

	p = popen(cmd)
	data = p.readlines()

	if len(data) == 0:
		return 'Error', 'Error', 'Error'
	
	obsCode = upper(strip(data[0]))
	obsSeg = ''

	if obsCode[0:5] == 'ERROR':
		return 'Error', 'Error', 'Error'

	if len(obsCode) > 3:
		if obsCode[0].isalpha() and obsCode[1].isalpha() and obsCode[2].isdigit():
			for i in range(3, len(obsCode)):
				if obsCode[i].isalpha():
					obsSeg = obsCode[i:]
					obsCode = obsCode[0:i]
					break
		if obsCode[0].isalpha() and obsCode[1].isdigit():
			for i in range(2, len(obsCode)):
				if obsCode[i].isalpha():
					obsSeg = obsCode[i:]
					obsCode = obsCode[0:i]
					break
		

	stationTimes = {}
	for d in data[1:]:
		s = split(strip(d))
		stationTimes[upper(s[0])] = [float(s[1])-prestartTime/86400.0, float(s[2])+poststopTime/86400.0]

	print 'This is experiment %s %s' % (obsCode, obsSeg)

	return obsCode, obsSeg, stationTimes

def mjd2datetime(mjd):
	mon = ['JAN', 'FEB', 'MAR', 'APR', 'MAY', 'JUN', 'JUL', 'AUG', 'SEP', 'OCT', 'NOV', 'DEC']
	dt = datetime.timedelta(int(mjd), int((mjd - int(mjd))*86400.0 + 0.5))
	t = mjd0 + dt
	return '%04d%s%02d %02dh%02dm%02ds' % (t.year, mon[t.month-1], t.day, t.hour, t.minute, t.second)

# take string date (d) and time (t), as formatted above, and return MJD
def vlba2mjd(d, t):
	monnames = ['JAN', 'FEB', 'MAR', 'APR', 'MAY', 'JUN', 'JUL', 'AUG', 'SEP', 'OCT', 'NOV', 'DEC']
	yr = int(d[0:4])
	monname = d[4:7]
	mn = 0
	for m in range(len(monnames)):
		if monname == monnames[m]:
			mn = m+1
	da = int(d[7:9])
	hr = int(t[0:2])
	mi = int(t[3:5])
	se = int(t[6:8])
	mjd = (datetime.datetime(yr, mn, da, 0, 0) - mjd0).days + hr/24.0 + mi/1440.0 + se/86400.0

	return mjd

def sortmetric(x):
	y = split(x)
	return vlba2mjd(y[1], y[2])

def rmObservation(orig, expt, station):
	observations = []

	for o in orig:
		# calc time
		# keep only obs from last 7 days and beyond
		v = split(strip(o), '>')
		s = split(v[0])
		if len(s) < 5 or len(v) < 2:
			observations.append(o)
			continue
		expt0 = s[0]
		if expt0 == expt:
			continue	# don't keep old entry
		observations.append(o)

	# sort by start time
	observations.sort(key=sortmetric)

	# glue: if removed observation was between two copies of same
	# experiment, assume it was interrupted by the observation that
	# was removed, so put them back together
	index = 0
	while len(observations) > index+1:
		v1 = split(observations[index], '>')
		s1 = split(v1[0])
		v2 = split(observations[index+1], '>')
		s2 = split(v2[0])
		if s1[0] == s2[0] and v1[1] == v2[1]:
			# copy end date,time from second expt to first
			observations[index] = '%s %s %s %s %s > %s' % (s1[0], s1[1], s1[2], s2[3], s2[4], v1[1])
			observations.pop(index+1)
		else:
			index += 1

	return observations

# -----------------

VLBAStations = ['br', 'fd', 'hn', 'kp', 'la', 'mk', 'nl', 'ov', 'pt', 'sc']
vexFiles = []
antennas = []
force = False

for a in argv[1:]:
	if a[0] == '-':
		if a in ['-h', '--help']:
			usage()
			exit(1)
		elif a in ['-v', '--verbose']:
			verbose += 1
		elif a in ['-q', '--quiet']:
			verbose -= 1
		elif a in ['-f', '--force']:
			force = True
		else:
			print 'Unknown option "%s"\n' % a
			exit(1)
	elif len(a) > 3:
		vexFiles.append(a)
	else:
		antennas.append(a)

if len(vexFiles) == 0:
	usage()
	exit(0)

if len(vexFiles) > 1:
	print 'The following vex files will be unqueued:'
	for vexFile in vexFiles:
		print '  %s' % vexFile
	if not force:
		print 'If this is not what you intend, use ^C now to stop.'
		print 'Otherwise press Enter to continue.'
		stdin.readline()

cwd = getcwd()

if find(upper(cwd), 'MARK5C') < 0:
	if isdir(cwd+'/MARK5C') > 0:
		if not force:
			print '\nWarning: %s/MARK5C is presumably where you want to run this.' % cwd
			print 'Try again with -f to force the operation'
		else:
			print '\nContinuing because of -f (or --force) even though %s/MARK5C' % cwd
			print 'seems more likely to be where you want to run this.'
	elif isdir(cwd+'/../MARK5C') > 0:
		if not force:
			print '\nWarning: %s/../MARK5C is presumably where you want to run this.' % cwd
			print 'Try again with -f to force the operation'
		else:
			print '\nContinuing because of -f (or --force) even though %s/MARK5C' % cwd
			print 'seems more likely to be where you want to run this.'
	else:
		print '\nYou are running %s from a non-Mark5C directory.' % program
		print 'I hope this is what you want!\n'
	
for vexFile in vexFiles:
	if not isfile(vexFile):
		print 'Error: cannot find file %s' % vexFile
		exit(0)

for vexFile in vexFiles:
	if vexFile[0] != '/':
		vexFile = '%s/%s' % (cwd, vexFile)

	obsCode, obsSeg, stationTimes = vexPeek(vexFile)

	scripts = []

	for s in stationTimes:
		scriptName = upper(obsCode+obsSeg+'.'+s)+'.py'
		scripts.append(scriptName)

	scripts.sort()

	print 'scripts=', scripts

	chdir('/tmp')

	for script in scripts:
		s = split(script, '.')
		station = lower(s[-2])
		if len(antennas) > 0 and not station in antennas:
			print '** Skipping antenna %s from vex file %s' % (upper(station), vexFile)
			continue
		if not station in VLBAStations:
			print '** Non-VLBA station %s being skipped' % upper(station)
			continue
		expt = upper(s[0])
		print '\n==========================================================================='
		if station == 'gb':
			cc = 'gb-cc.gb.nrao.edu'

			continue	# GB not yet handled per the request of GB staff
		else:
			cc = '%s-cc.vlba.nrao.edu' % station
		
		upperStation = upper(station)
		timeRange = stationTimes[upperStation]
		startDate = mjd2datetime(timeRange[0])
		stopDate = mjd2datetime(timeRange[1])
		print 'STATION %s : was to observe %s from %s to %s' % (upperStation, expt, startDate, stopDate)
		print '===========================================================================\n'

		print 'Removing %s from %s' % (script, cc)
		execute('scp vlbamon@%s:%s/%s . 2>&1' % (cc, ccScriptDir, observTxFile), 0)
		if not isfile(observTxFile):
			execute('touch %s' % observTxFile)

		observations = open(observTxFile).readlines()
		observations = rmObservation(observations, expt, station)
		f = open(observTxFile, 'w')
		for o in observations:
			f.write(o)
		f.close()

		print 'New contents of %s at %s: (only last %d lines shown)' % (observTxFile, upperStation, linesToShow)
		system('tail -n %d %s' % (linesToShow, observTxFile))
		print ''
		execute('ssh vlbamon@%s rm -f %s/%s 2>&1' % (cc, ccScriptDir, script), 0)
		execute('scp %s vlbamon@%s:%s 2>&1' % (observTxFile, cc, ccScriptDir), 0)

chdir(cwd)