# This file is part of h5py, a Python interface to the HDF5 library.
#
# http://www.h5py.org
#
# Copyright 2008-2013 Andrew Collette and contributors
#
# License:  Standard 3-clause BSD; see "license.txt" for full license terms
#           and contributor agreement.

"""
    Attributes testing module

    Covers all operations which access the .attrs property, with the
    exception of data read/write and type conversion.  Those operations
    are tested by module test_attrs_data.
"""

import numpy as np
import collections

from .common import TestCase, ut

from h5py.highlevel import File
from h5py import h5a
from h5py.highlevel import AttributeManager


class BaseAttrs(TestCase):

    def setUp(self):
        self.f = File(self.mktemp(), 'w')

    def tearDown(self):
        if self.f:
            self.f.close()


class TestAccess(BaseAttrs):

    """
        Feature: Attribute creation/retrieval via special methods
    """

    def test_create(self):
        """ Attribute creation by direct assignment """
        self.f.attrs['a'] = 4.0
        self.assertEqual(list(self.f.attrs.keys()), ['a'])
        self.assertEqual(self.f.attrs['a'], 4.0)

    def test_overwrite(self):
        """ Attributes are silently overwritten """
        self.f.attrs['a'] = 4.0
        self.f.attrs['a'] = 5.0
        self.assertEqual(self.f.attrs['a'], 5.0)

    def test_rank(self):
        """ Attribute rank is preserved """
        self.f.attrs['a'] = (4.0, 5.0)
        self.assertEqual(self.f.attrs['a'].shape, (2,))
        self.assertArrayEqual(self.f.attrs['a'], np.array((4.0,5.0)))

    def test_single(self):
        """ Attributes of shape (1,) don't become scalars """
        self.f.attrs['a'] = np.ones((1,))
        out = self.f.attrs['a']
        self.assertEqual(out.shape, (1,))
        self.assertEqual(out[()], 1)

    def test_access_exc(self):
        """ Attempt to access missing item raises KeyError """
        with self.assertRaises(KeyError):
            self.f.attrs['a']


class TestDelete(BaseAttrs):

    """
        Feature: Deletion of attributes using __delitem__
    """

    def test_delete(self):
        """ Deletion via "del" """
        self.f.attrs['a'] = 4.0
        self.assertIn('a', self.f.attrs)
        del self.f.attrs['a']
        self.assertNotIn('a', self.f.attrs)

    def test_delete_exc(self):
        """ Attempt to delete missing item raises KeyError """
        with self.assertRaises(KeyError):
            del self.f.attrs['a']


class TestUnicode(BaseAttrs):

    """
        Feature: Attributes can be accessed via Unicode or byte strings
    """

    def test_ascii(self):
        """ Access via pure-ASCII byte string """
        self.f.attrs[b"ascii"] = 42
        out = self.f.attrs[b"ascii"]
        self.assertEqual(out, 42)

    def test_raw(self):
        """ Access via non-ASCII byte string """
        name = b"non-ascii\xfe"
        self.f.attrs[name] = 42
        out = self.f.attrs[name]
        self.assertEqual(out, 42)

    def test_unicode(self):
        """ Access via Unicode string with non-ascii characters """
        name = "Omega \u03A9"
        self.f.attrs[name] = 42
        out = self.f.attrs[name]
        self.assertEqual(out, 42)


class TestCreate(BaseAttrs):

    """
        Options for explicit attribute creation
    """

    def test_named(self):
        """ Attributes created from named types link to the source type object
        """
        self.f['type'] = np.dtype('u8')
        self.f.attrs.create('x', 42, dtype=self.f['type'])
        self.assertEqual(self.f.attrs['x'], 42)
        aid = h5a.open(self.f.id, b'x')
        htype = aid.get_type()
        htype2 = self.f['type'].id
        self.assertEqual(htype, htype2)
        self.assertTrue(htype.committed())


class TestMutableMapping(BaseAttrs):
    '''Tests if the registration of AttributeManager as a MutableMapping
    behaves as expected
    '''
    def test_resolution(self):
        assert issubclass(AttributeManager, collections.MutableMapping)
        assert isinstance(self.f.attrs, collections.MutableMapping)

    def test_validity(self):
        '''
        Test that the required functions are implemented.
        '''
        AttributeManager.__getitem__
        AttributeManager.__setitem__
        AttributeManager.__delitem__
        AttributeManager.__iter__
        AttributeManager.__len__
