"""
This section contains all the utility definitions and functions for gathering the PGE03 inputs.
"""

import os
import glob
from datetime import datetime, timedelta

PGE03_INSTALL = os.environ['PGE03_INSTALL']
NCFTPGET = os.environ['NCFTPGET']

# THESE SHOULDNT BE MESSED WITH ON MODISCODE, ADD TO ENVIRON EVENTUALLY?
MODAPSCONF = "$HOME/pyPGE03/conf.csh"
PERL = "/data/common/programfiles/bin/perl"

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

M02QKM_DIR = os.environ['M02QKM_DIR']
M021KM_DIR = os.environ['M021KM_DIR']
GFS_DIR    = os.environ['GFS_DIR'   ]
SST_DIR    = os.environ['SST_DIR'   ]
ENG_DIR    = os.environ['ENG_DIR'   ]
NISE_DIR   = os.environ['NISE_DIR'  ]

WORK_DIR   = os.environ['WORK_DIR'  ] # "/work/y%(yyyy)s_m%(mm)s_d%(dd)s_h%(hh)s_M%(MM)s"

M02QKM_PATTERN = M02QKM_DIR + "/MOD02QKM.A%(yyyy)s%(jjj)s.%(hh)s%(MM)s.*"     # MOD02QKM.A2011209.1655.005.flo.hdf
M021KM_PATTERN = M021KM_DIR + "/MOD021KM.A%(yyyy)s%(jjj)s.%(hh)s%(MM)s.*"     # MOD021KM.A2011171.1555.005.flo.hdf
GFS_PATTERN    = GFS_DIR    + "/gdas1.PGrbF00.%(yy)s%(mm)s%(dd)s.%(hh)sz"               # gdas1.PGrbF00.110620.00z
SST_PATTERN    = SST_DIR    + "/oisst.%(yyyy)s%(mm)s%(dd)s"                             # oisst.20110615
ENG_PATTERN    = ENG_DIR    + "/eng.%(yy)s%(mm)s%(dd)s"                                 # eng.110620
NISE_PATTERN   = NISE_DIR   + "/NISE_SSMIF13_%(yyyy)s%(mm)s%(dd)s.HDFEOS"               # NISE_SSMIF13_20110620.HDFEOS


REMOTE_GFS  = "/pub/eosdb/ancillary/%(yyyy)s_%(mm)s_%(dd)s_%(jjj)s/gdas1.PGrbF00.%(yy)s%(mm)s%(dd)s.*"
REMOTE_ENG  = "/pub/eosdb/ancillary/%(yyyy)s_%(mm)s_%(dd)s_%(jjj)s/eng.%(yy)s%(mm)s%(dd)s"
REMOTE_NISE = "/pub/eosdb/ancillary/%(yyyy)s_%(mm)s_%(dd)s_%(jjj)s/NISE_SSMIF13_%(yyyy)s%(mm)s%(dd)s.HDFEOS"
REMOTE_SST  = "/pub/eosdb/ancillary/SST/oisst.%(yyyy)s%(mm)s%(dd)s"

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

def mk_remote(pattern, date):
	return date_fill_unsafe(pattern, date)


def mk_sst_remote(pattern, date):
	date = get_sst_date(date)
	return mk_remote(pattern, date)


# Local filenames need to be checked if they exist - can't do that very well with remote!
def date_fill_safe(pattern, date):
	reps = make_rep_dict(date)
	fpattern = pattern % reps
	files = glob.glob(fpattern)
	if len(files) > 1:
		raise IOError, "Too many files match: %s" % (fpattern)
	if len(files) < 1:
#		raise IOError, "No files match: %s" % (fpattern)
		print "Warning: no files match: %s" % (fpattern)
                return "MISSING"
	fname = files[0]
	if not os.path.exists(fname):
		# This should never happen due to above checks, but just in case...
		raise IOError, "File not found: %s" % (fname)
	print fname
	return fname


def date_fill_unsafe(pattern, date):
	reps = make_rep_dict(date)
	return pattern % reps


# SST has 7 day gaps so we need to find the one before
# FIXME: check that this algo is the right way to pick the SST to use!
first_SST = datetime(2000, 1, 5)
def get_sst_date(date):
	ofirst = first_SST.toordinal()
	odate = date.toordinal()

	odiff = odate - ofirst
	days_off = odiff % 7  # sst made every 7 days

	sst_date = date.fromordinal(odate - days_off)
	return sst_date


def get_gfs_dates(date):
	gfs_early = date.replace(hour=(date.hour - (date.hour % 6)), minute=0)
	gfs_late = gfs_early + timedelta(hours=6)
	return gfs_early, gfs_late


def jday(date):
	import datetime   # FIXME: need the base 'datetime' for datetime.date below!
	return date.toordinal() - datetime.date(date.year,1,1).toordinal() + 1	


def make_rep_dict(date):
	reps = {}
	reps["yyyy"] = "%04d" % (date.year)
	reps["yy"]   = "%02d" % (date.year % 100)
	reps["mm"]   = "%02d" % (date.month)
	reps["jjj"]  = "%03d" % (jday(date))
	reps["dd"]   = "%02d" % (date.day)
	reps["hh"]   = "%02d" % (date.hour)
	reps["MM"]   = "%02d" % (date.minute)
	return reps


# working dir doesn't always exist!
def date2workdir(date):
	return date_fill_unsafe(WORK_DIR, date)

def date2m02qkm(date):
	return date_fill_safe(M02QKM_PATTERN, date)

def date2m021km(date):
	return date_fill_safe(M021KM_PATTERN, date)

def date2eng(date):
  return date_fill_safe(ENG_PATTERN, date)

def date2nise(date):
	return date_fill_safe(NISE_PATTERN, date)

def date2gfs(date):
	egfs, lgfs = get_gfs_dates(date)
	efname = date_fill_safe(GFS_PATTERN, egfs)
	lfname = date_fill_safe(GFS_PATTERN, lgfs)
	return efname, lfname

def date2sst(date):
	date = get_sst_date(date)
	return date_fill_safe(SST_PATTERN, date)




# TESTS!
if __name__ == "__main__":
	pass
# OLD:	now = datetime.now()
# OLD:	print jday(now)
# OLD:	print make_rep_dict(now)
# OLD:	print date2workdir(now)
# OLD:	print date2m02qkm(now)
# OLD:	print date2m021km(now)
# OLD:	print date2gfs(now)
# OLD:	print date2sst(now)
# OLD:	print date2eng(now)
# OLD:	print date2nise(now)