#!/usr/bin/env python

usage = \
"""
This searches through a database file to find which entries overlap with
the supplied MJD range. The indices listed correspond to those to be found
on the summary page http://deneb.astro.warwick.ac.uk/phsaap/v404cyg/data/
The file is downloaded via http each time. If you are not sure of the
appropriate time range, enter 0 0 the first time.
"""

import os
import argparse
import json
import urllib2

if __name__ == '__main__':

    parser = argparse.ArgumentParser(description=usage)

    # positional
    parser.add_argument('mjd1',  type=float, help='start of time range')
    parser.add_argument('mjd2',  type=float, help='end of time range')

    # OK, done with arguments.
    args = parser.parse_args()

    # Download database file
    url = 'http://deneb.astro.warwick.ac.uk/phsaap/v404cyg/data/v404cyg.json'
    response = urllib2.urlopen(url)
    jstring = response.read()
    results = json.loads(jstring)
    print len(results),'entries read from',url

    print '\nEntry Contact name               Telescope                  Instrument                 Waveband(s)\n' 

    nover = 0
    tmin = +1.e10
    tmax = -1.e10
    for entry in results:
        for start, end in entry['times']:
            tmin = min(tmin, start)
            tmax = max(tmax, end)
            if start < args.mjd2 and end > args.mjd1:
                print '{0:3d}   {1:26s} {2:26s} {3:26s} {4:10s}'.format(
                    entry['nentry'],entry['Name'][:26],entry['Telescope'][:26],
                    entry['Instrument'][:26],entry['Wavebands'])
                nover += 1
                break

    if nover == 0:
        print 'Time range found:',tmin,'to',tmax