#!/usr/bin/env python

import psycopg2 as pg
from sys import argv, exit
from os import environ, popen
from string import lower, upper, split, strip

program = 'db2flag'
author = 'Walter Brisken'
version = '0.4'
verdate = '20150730'

# Note: if more MIB-based flags are to be supported there are two places in
# the code, identified in comments, where additions need to be made.

def fetchVLBAMon2xmlFlags(start, stop):

	print 'Getting Mon2xml FLAGGER records from database.  Be patient...'

	dbAccess = environ['VLBAMPTS_DB']

	# query to get VME alerts that were funneled into the VLBAMPTS database via mon2xml
	query = """
	SELECT hostname, timestamp, monpointvalue from mcdata 
	WHERE devicename = 'FLAGGER' 
	  AND monpointname = 'upper_flag'
	  AND timestamp between %14.8f AND %14.8f
	ORDER BY timestamp""" % (start, stop) 

	db = pg.connect(dbAccess).cursor()
	db.execute(query)
	
	return db.fetchall()


def fetchVLBAMibFlags(start, stop):

	print 'Getting MIB alert records from database.  Be patient...'

	dbAccess = environ['VLBAMPTS_DB']

	# look for MIB-native alerts
	#   For now, just look for subreflector problems and L404 unlock.  Later, there may be more...
	# NOTE: now I assume 1 L404 per site, with side A wired to replace L104-1 and B for L104-2.

	# Here is the first place where additions are needed if more MIB-based flags are to be supported.
	query = """
	SELECT hostname, timestamp, devicename, monpointname, alert from alertdata 
	WHERE    ( ( devicename='M402' AND monpointname='Ell_Cmd_Stat_Mismatch' )
	        OR ( devicename='L404' AND ( monpointname='Lock_Detect_A' OR monpointname='Lock_Detect_B' ) ) )
	  AND timestamp between %14.8f AND %14.8f
	ORDER BY timestamp""" % (start, stop)

	db = pg.connect(dbAccess).cursor()
	db.execute(query)

	return db.fetchall()

def getVLBAFlags(mon2xmlFlags, mibFlags, start, stop, station, filename):

	nRec = 0

	# First do Legacy portion (alerts from mon2xml via database)

	# The reasons below must be <= 24 chars between single quotes
	legacyFlagTypes = \
	[ \
		( 0x00001, "'Synth 1 out of lock'" ), \
		( 0x00002, "'Synth 2 out of lock'" ), \
		( 0x00004, "'Synth 3 out of lock'" ), \
		( 0x00080, "'Source change'" ), \
		( 0x01000, "'Subreflector posn error'" ), \
		( 0x04000, "'Antenna not pointing'" ), \
		( 0x08000, "'Antenna position error'") \
	]

	flagstart = [-1] * len(legacyFlagTypes)

	out = open(filename, 'w')
	print 'Formatting %s flag data' % upper(station)

	lastflag = 0

	for hostname, timestamp, value in mon2xmlFlags:
		if lower(hostname[0:2]) != lower(station):
			continue
			
		flag = int(value)

		for b in range(len(legacyFlagTypes)):
			if (flag & legacyFlagTypes[b][0]) != (lastflag & legacyFlagTypes[b][0]):
				if flag & legacyFlagTypes[b][0]:
					if timestamp > start:
						flagstart[b] = timestamp
					else:
						flagstart[b] = start
				else:
					if timestamp > start:
						# only bother to write flag if part of it happened during the timerange
						out.write('%s %12.6f %12.6f %d %s\n' % (upper(station), flagstart[b], timestamp, -1, legacyFlagTypes[b][1]))
						nRec += 1
					flagstart[b] = -1

		lastflag = flag

	for b in range(len(legacyFlagTypes)):
		if flagstart[b] > 0:
			out.write('%s %12.6f %12.6f %d %s\n' % (upper(station), flagstart[b], stop, -1, legacyFlagTypes[b][1]))
			nRec += 1

	# Do MIB portion

	# Here is the second place where new MIB-based flags are generated.
	# The device name and mon points in this table are case-insensitive.
	# For modules types that have multiple instances at one site, add -1 or -2 to the device name as appropriate
	mibFlagTypes = \
	[ \
		("M402.Ell_Cmd_Stat_Mismatch", "'Ellipsoid posn error'"), \
		("L404-1.Lock_Detect_A",       "'Syn 1 out of lock (L404)'"), \
		("L404-1.Lock_Detect_B",       "'Syn 2 out of lock (L404)'") \
	]

	flagstart = [-1] * len(mibFlagTypes)

	for hostname, timestamp, devicename, monpointname, alert in mibFlags:

		if lower(hostname[0:2]) != lower(station):
			continue

		if hostname[-2] == '-':
			# device of form L404-1 or L404-2
			flagDescriptor = lower(devicename + hostname[-2:] + '.' + monpointname)
		else:
			flagDescriptor = lower(devicename + '.' + monpointname)

		for b in range(len(mibFlagTypes)):
			if lower(mibFlagTypes[b][0]) == flagDescriptor:
				if alert and flagstart[b] < 0:
					if timestamp > start:
						flagstart[b] = timestamp
					else:
						flagstart[b] = start
				elif not alert and flagstart[b] > 0:
					if timestamp > start:
						# only bother to write flag if part of it happened during the timerange
						out.write('%s %12.6f %12.6f %d %s\n' % (upper(station), flagstart[b], timestamp, -1, mibFlagTypes[b][1]))
						nRec += 1
					flagstart[b] = -1
				break

	for b in range(len(mibFlagTypes)):
		if flagstart[b] > 0:
			out.write('%s %12.6f %12.6f %d %s\n' % (upper(station), flagstart[b], stop, -1, mibFlagTypes[b][1]))
			nRec += 1
	
	print '  %d records found' % nRec

	out.close()
	# if nRec is zero, delete output file

	return nRec;

def getGBFlags(start, stop, guardTime, filename):
	pass

def getVLAFlags(start, stop, guardTime, filename):
	pass

				

# Returns obsCode, obsSeg, { ANT : [startmjd, stopmjd] }
def vexPeek(vexFile, verbose):
	
	cmd = 'vexpeek %s' % 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;
		

	antennaTimes = {}
	for d in data[1:]:
		s = split(strip(d))
		antennaTimes[upper(s[0])] = [float(s[1]), float(s[2])]

	if verbose > 0:
		print 'This is experiment %s %s' % (obsCode, obsSeg)

	return obsCode, obsSeg, antennaTimes

def exptTimeRange(antennaTimes):
	start = 1e9
	stop = -1e9
	for a in antennaTimes.keys():
		if antennaTimes[a][0] < start:
			start = antennaTimes[a][0]
		if antennaTimes[a][1] > stop:
			stop = antennaTimes[a][0]
	return [start, stop]

def usage(pgm):
	print '\n%s ver. %s  %s  %s\n' % (program, version, author, verdate)
	print 'Usage: db2flag [options] <vexFile> [ant1 [ant2 ... ] ]\n'
	print 'Options can be:\n'
	print '  --help'
	print '  -h       print this help information\n'
	print '  --verbose'
	print '  -v       be more verbose in execution\n'
	print '  --force'
	print '  -f       force operation on unrecognized antenna\n'


vexFile = None
antennas = []
verbose = 0
force = False
guardTime = 0.04	# [days] : extend time before experiment to get pre-existing conditions

for a in argv[1:]:
	if a[0] == '-':
		if a in ['-h', '--help']:
			usage(argv[0])
			exit(0)
		if a in ['-v', '--verbose']:
			verbose += 1
		if a in ['-f', '--force']:
			force = True
		else:
			print 'Unknown option: %s' % a
			exit(0)
	elif vexFile == None:
		vexFile = a
	else:
		antennas.append(upper(a))

if vexFile == None:
	print 'Incomplete command line.  Run with --help for info.'
	exit(0)

obsCode, obsSeg, antennaTimes = vexPeek(vexFile, verbose)

if not force:
	nWrongAntenna = 0
	for a in antennas:
		if a not in antennaTimes.keys():
			print 'Error: %s is not in this vex file' % a
			nWrongAntenna += 1
	if nWrongAntenna > 0:
		exit(0)
else:
	for a in antennas:
		if a not in antennaTimes.keys():
			antennaTimes[a] = exptTimeRange(antennaTimes)

if len(antennas) == 0:
	antennas = antennaTimes.keys()


# different antennas have their data stored in different DBs / mon points...

ignored = ''

print '\n%s is now collecting flag data...' % program

start = 1.0e12
stop = -1.0e12
for a in antennas:
	if not a in ['BR', 'FD', 'HN', 'KP', 'LA', 'MK', 'NL', 'OV', 'PT', 'SC']:
		continue
	if antennaTimes[a][0] < start:
		start = antennaTimes[a][0]
	if antennaTimes[a][1] > stop:
		stop = antennaTimes[a][1]

if start < stop:
	vlbaMon2xmlFlags = fetchVLBAMon2xmlFlags(start-guardTime, stop)
	vlbaMibFlags = fetchVLBAMibFlags(start-guardTime, stop)

for a in antennas:
	if a == 'GB':
		flagFile = '%s%s.%s.flag' % (lower(obsCode), lower(obsSeg), lower(a))
		getGBFlags(antennaTimes[a][0], antennaTimes[a][1], guardTime, flagFile)
	elif a == 'Y':
		flagFile = '%s%s.%s.flag' % (lower(obsCode), lower(obsSeg), lower(a))
		getVLAFlags(antennaTimes[a][0], antennaTimes[a][1], guardTime, flagFile)
	elif a in ['BR', 'FD', 'HN', 'KP', 'LA', 'MK', 'NL', 'OV', 'PT', 'SC']:
		flagFile = '%s%s.%s.flag' % (lower(obsCode), lower(obsSeg), lower(a))
		getVLBAFlags(vlbaMon2xmlFlags, vlbaMibFlags, antennaTimes[a][0], antennaTimes[a][1], a, flagFile)
	else:
		ignored += ' %s' % a

if len(ignored) > 0:
	print '\nThe following antennas are not (yet) supported by %s: %s' % (program, ignored)

print ''