#!/usr/bin/env python
# vim: ft=python ts=8 sts=4 sw=4 expandtab autoindent smartindent
""" Find the trigger time for Differenctial Scanning Calorimetry data in nx.hdf files. """

import sys
import os
import h5py
import argparse
import time
from collections import defaultdict

class SkipFile(BaseException):
    """This exception should be raised to skip processing a file"""
    pass

PARSER = argparse.ArgumentParser(
    description = """Report the time offset for the start of the DSC profile relative to the start time of the histogram data.
    This program can process multiple hdf files by specifying the path to the first file and the number of files to process.
    You can also speficy a list of 'file_path numfile' pairs.""",
    usage='dsc file_path numfile {file_path numfile}'
)
PARSER.add_argument('files', nargs='+', help = 'List of "file_path numfile" pairs')
ARGS = PARSER.parse_args()

FAILS = defaultdict(list)
for startfile, num in zip(ARGS.files[0::2], ARGS.files[1::2]):
    numfiles = int(num)
    hfdir = os.path.dirname(startfile)
    hfbase = os.path.basename(startfile)
    idx = hfbase.find('.')
    startFID = hfbase[:idx]
    ext = hfbase[idx:]
    idnum = int(startFID[3:])
    inst_abname = hfbase[:3]

    hfval = {}
    print
    for i in range(numfiles):
        try:
            currid = idnum + i
            fileID = inst_abname + '%07d' % currid
            if (hfdir == ''):
                nxfile = fileID + ext
            else:
                nxfile = hfdir + '/' + fileID + ext

            try:
                hf = h5py.File(nxfile, 'r')
            except:
                FAILS['badfile'].append(nxfile)
                continue

            if (hfbase.startswith('QKK')):
                rootpath = fileID + '/'
            else:
                rootpath = 'entry1/'

            for dpath in ['time_stamp', 'instrument/detector/start_time', 'sample/dsc_val']:
                dscpath = rootpath + dpath
                if dscpath in hf:
                    hfval[dpath] = hf[dscpath][:]
                else:
                    FAILS['badpath:{0}'.format(dpath)].append(nxfile)
                    hf.close()
                    raise SkipFile

            print fileID
            datiter = {}
            dat_hasnext = 0
            time_tuple = time.strptime(hf[rootpath + 'start_time'][0], '%Y-%m-%d %H:%M:%S')
            hfval['time_stamp'] += time.mktime(time_tuple)
            hfval['time_stamp'] -= hfval['instrument/detector/start_time']
            dsc0 = hfval['sample/dsc_val'][0]
            no_transition = True
            for i in range(1, len(hfval['sample/dsc_val'][1:])):
                dsc1 = hfval['sample/dsc_val'][i]
                if abs(dsc1 - dsc0) > 1.9:
                    no_transition = False
                    msg = 'dsc_val transition from {dsc0} to {dsc1} volts at {time} seconds from detector start time, array index = {index}'
                    print msg.format(dsc0=dsc0, dsc1=dsc1, time=hfval['time_stamp'][i], index=i)
                dsc0 = dsc1

            if no_transition:
                print 'dsc_val no transition'

            print
            hf.close()
        except SkipFile:
            continue

for k in FAILS.keys():
    if (len(FAILS[k])):
        print >> sys.stderr, 'Skipped following files. Reason = ', k
        print >> sys.stderr, FAILS[k]