"""

Part of the tagit test suite.
A copy of the license is provided with the project.
Author: Matthias Baumgartner, 2022
"""
# standard imports
from datetime import datetime, timezone
import math
import os
import shutil
import sys
import tempfile
import unittest

# external imports
import pyexiv2

# inner-module imports
from tagit.parsing import parse_datetime

# objects to test
from tagit.shared import time as ttime

# constants
sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), '..'))
from testdata import IMAGE_VALID


## code ##

class TestTTime(unittest.TestCase):
    def setUp(self):
        self.img = tempfile.mkstemp(prefix='tagit_')[1]
        shutil.copy(IMAGE_VALID['path'], self.img)
        self.empty = tempfile.mkstemp(prefix='tagit_')[1]
        # ensure correct file date (fixed, in utc)
        #os.system('touch -d "29 Oct 2015 14:20:56" {}'.format(self.empty))
        os.utime(self.empty, (1446124856, 1446124856))

    def tearDown(self):
        if os.path.exists(self.img): os.unlink(self.img)
        if os.path.exists(self.empty): os.unlink(self.empty)

    def test_conversions(self):
        """
        Files, via os.stat (Timestamp in UTC, Local timezone)
        Images, from Exif (Timestamp in camera local time, No timezone)
        Images, from Xmp (Timestamp in camera local time, Timezone from Xmp)
        now (Timestamp in UTC, Local timezone)
        Database (timestamp in UTC, timestamp in local time)
        """
        # prepare
        stat = os.stat(self.empty)
        meta = pyexiv2.ImageMetadata(self.img)
        meta.read()
        # Create time objects in the proper format

        # Manually defined
        dt_manual = datetime(2015, 10, 29, 14, 20, 56)

        # os.stat
        dt_stat = datetime.fromtimestamp(stat.st_mtime)

        # exif
        dt_exif = meta['Exif.Photo.DateTimeOriginal'].value.replace(tzinfo=ttime.NoTimeZone)

        # xmp
        dt_xmp = meta['Xmp.exif.DateTimeOriginal'].value

        # user-specified
        dt_user = parse_datetime("29.10.2015, 14:20:56")

        # now
        dt_now = datetime.now()

        # UTC offset
        offset_ref  = dt_manual.replace(tzinfo=timezone.utc).timestamp() - dt_manual.timestamp()
        offset_ref /= 3600
        offset_now  = dt_now.replace(tzinfo=timezone.utc).timestamp() - dt_now.timestamp()
        offset_now /= 3600

        # Conversions
        # Comparable local time
        self.assertEqual(math.floor(ttime.timestamp_loc(dt_manual) % (3600 * 24) / 3600), 14 )
        self.assertEqual(math.ceil( ttime.timestamp_loc(dt_manual) % (3600 * 24) / 3600), 15 )
        self.assertEqual(ttime.timestamp_loc(dt_manual) % (3600 * 24), 51656 )
        self.assertEqual(ttime.timestamp_loc(dt_manual), ttime.timestamp_loc(dt_stat) )
        self.assertEqual(ttime.timestamp_loc(dt_manual), ttime.timestamp_loc(dt_exif) )
        self.assertEqual(ttime.timestamp_loc(dt_manual), ttime.timestamp_loc(dt_xmp)  )
        self.assertEqual(ttime.timestamp_loc(dt_manual), ttime.timestamp_loc(dt_user) )

        # UTC offset
        self.assertEqual(ttime.utcoffset(dt_manual), offset_ref)
        self.assertEqual(ttime.utcoffset(dt_stat), offset_ref)
        self.assertEqual(ttime.utcoffset(dt_exif), None)
        self.assertEqual(ttime.utcoffset(dt_xmp), 11)
        self.assertEqual(ttime.utcoffset(dt_user), offset_ref)
        self.assertEqual(ttime.utcoffset(dt_now), offset_now)

        # Comparable UTC
        self.assertEqual(ttime.timestamp_utc(dt_now),
            ttime.timestamp_loc(dt_now) - 3600 * offset_now)
        self.assertEqual(ttime.timestamp_utc(dt_manual),
            ttime.timestamp_loc(dt_manual) - 3600 * offset_ref )
        self.assertEqual(ttime.timestamp_utc(dt_stat),
            ttime.timestamp_loc(dt_stat) - 3600 * offset_ref)
        self.assertEqual(ttime.timestamp_utc(dt_user),
            ttime.timestamp_loc(dt_user) - 3600 * offset_ref)
        self.assertEqual(ttime.timestamp_utc(dt_exif),
            ttime.timestamp_loc(dt_exif))
        self.assertEqual(ttime.timestamp_utc(dt_xmp),
            ttime.timestamp_loc(dt_xmp) - 3600 * ttime.utcoffset(dt_xmp))

        # Conversion back
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_now)).timestamp(), dt_now.timestamp())
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_manual)).timestamp(), dt_manual.timestamp())
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_stat)).timestamp(), dt_stat.timestamp())
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_user)).timestamp(), dt_user.timestamp())
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_exif)).timestamp(), dt_exif.timestamp())
        self.assertEqual(ttime.from_timestamp_utc(
            ttime.timestamp_utc(dt_xmp)).timestamp(), dt_xmp.timestamp())

        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_now))), ttime.timestamp_loc(dt_now))
        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_manual))), ttime.timestamp_loc(dt_manual))
        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_stat))), ttime.timestamp_loc(dt_stat))
        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_user))), ttime.timestamp_loc(dt_user))
        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_exif))), ttime.timestamp_loc(dt_exif))
        self.assertEqual(ttime.timestamp_loc(ttime.from_timestamp_loc(
            ttime.timestamp_loc(dt_xmp))), ttime.timestamp_loc(dt_xmp))

        # Conversion to local time + TZO for storage.library
        # This is used to store file infos

        # Retrieval in local time
        # This is used to search for files in a given time range

        # Retrieval in local time + TZO from storage.library

        # Retrieve in UTC from storage.library
        # This is used to compare files (e.g. syncing) across platforms


## main ##

if __name__ == '__main__':
    unittest.main()

## EOF ##