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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
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# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

import array
from datetime import date, datetime, timezone

import pytest
from nanoarrow._array import CArrayBuilder
from nanoarrow._utils import NanoarrowException
from nanoarrow.c_schema import c_schema_view

import nanoarrow as na
from nanoarrow import device


def test_c_array_from_c_array():
    c_array = na.c_array([1, 2, 3], na.int32())
    c_array_from_c_array = na.c_array(c_array)
    assert c_array_from_c_array.length == c_array.length
    assert c_array_from_c_array.buffers == c_array.buffers

    assert list(c_array.view().buffer(1)) == [1, 2, 3]


def test_c_array_from_capsule_protocol():
    class CArrayWrapper:
        def __init__(self, obj):
            self.obj = obj

        def __arrow_c_array__(self, *args, **kwargs):
            return self.obj.__arrow_c_array__(*args, **kwargs)

    c_array = na.c_array([1, 2, 3], na.int32())
    c_array_wrapper = CArrayWrapper(c_array)
    c_array_from_protocol = na.c_array(c_array_wrapper)
    assert c_array_from_protocol.length == c_array.length
    assert c_array_from_protocol.buffers == c_array.buffers

    assert list(c_array_from_protocol.view().buffer(1)) == [1, 2, 3]


def test_c_array_from_old_pyarrow():
    # Simulate a pyarrow Array with no __arrow_c_array__
    class MockLegacyPyarrowArray:
        def __init__(self, obj):
            self.obj = obj

        def _export_to_c(self, *args):
            return self.obj._export_to_c(*args)

    MockLegacyPyarrowArray.__module__ = "pyarrow.lib"

    pa = pytest.importorskip("pyarrow")
    array = MockLegacyPyarrowArray(pa.array([1, 2, 3], pa.int32()))

    c_array = na.c_array(array)
    assert c_array.length == 3
    assert c_array.schema.format == "i"

    assert list(c_array.view().buffer(1)) == [1, 2, 3]

    # Make sure that this heuristic won't result in trying to import
    # something else that has an _export_to_c method
    with pytest.raises(TypeError, match="Can't resolve ArrayBuilder"):
        not_array = pa.int32()
        assert hasattr(not_array, "_export_to_c")
        na.c_array(not_array)


def test_c_array_from_bare_capsule():
    c_array = na.c_array([1, 2, 3], na.int32())

    # Check from bare capsule without supplying a schema
    schema_capsule, array_capsule = c_array.__arrow_c_array__()
    del schema_capsule
    c_array_from_capsule = na.c_array(array_capsule)
    assert c_array_from_capsule.length == c_array.length
    assert c_array_from_capsule.buffers == c_array.buffers

    # Check from bare capsule supplying a schema
    schema_capsule, array_capsule = c_array.__arrow_c_array__()
    c_array_from_capsule = na.c_array(array_capsule, schema_capsule)
    assert c_array_from_capsule.length == c_array.length
    assert c_array_from_capsule.buffers == c_array.buffers

    assert list(c_array_from_capsule.view().buffer(1)) == [1, 2, 3]


def test_c_array_type_not_supported():
    msg = "Can't resolve ArrayBuilder for object of type NoneType"
    with pytest.raises(TypeError, match=msg):
        na.c_array(None)


def test_c_array_slice():
    array = na.c_array([1, 2, 3], na.int32())
    assert array.offset == 0
    assert array.length == 3

    array2 = array[:]
    assert array.offset == 0
    assert array.length == 3
    assert array.buffers == array2.buffers

    array2 = array[:2]
    assert array2.offset == 0
    assert array2.length == 2

    array2 = array[:-1]
    assert array2.offset == 0
    assert array2.length == 2

    array2 = array[1:]
    assert array2.offset == 1
    assert array2.length == 2

    array2 = array[-2:]
    assert array2.offset == 1
    assert array2.length == 2


def test_c_array_slice_errors():
    array = na.c_array([1, 2, 3], na.int32())

    with pytest.raises(TypeError):
        array[None]
    with pytest.raises(IndexError):
        array[4:]
    with pytest.raises(IndexError):
        array[:4]
    with pytest.raises(IndexError):
        array[1:0]


def test_c_array_shallow_copy():
    import gc
    import platform

    from nanoarrow._utils import get_pyobject_buffer_count

    if platform.python_implementation() == "PyPy":
        pytest.skip(
            "Reference counting/garbage collection is non-deterministic on PyPy"
        )

    gc.collect()
    initial_ref_count = get_pyobject_buffer_count()

    # Create an array with children
    array = na.c_array_from_buffers(
        na.struct({"col1": na.int32(), "col2": na.int64()}),
        3,
        [None],
        children=[na.c_array([1, 2, 3], na.int32()), na.c_array([4, 5, 6], na.int32())],
        move=True,
    )

    # The move=True should have prevented a shallow copy of the children
    # when constructing the array.
    assert get_pyobject_buffer_count() == initial_ref_count

    # Force a shallow copy via the array protocol and ensure we saved
    # references to two additional buffers.
    _, col1_capsule = array.child(0).__arrow_c_array__()
    assert get_pyobject_buffer_count() == (initial_ref_count + 1)

    _, col2_capsule = array.child(1).__arrow_c_array__()
    assert get_pyobject_buffer_count() == (initial_ref_count + 2)

    # Ensure that the references can be removed
    del col1_capsule
    assert get_pyobject_buffer_count() == (initial_ref_count + 1)

    del col2_capsule
    assert get_pyobject_buffer_count() == initial_ref_count


def test_c_array_builder_init():
    builder = CArrayBuilder.allocate()

    with pytest.raises(RuntimeError, match="CArrayBuilder is not initialized"):
        builder.is_empty()

    builder.init_from_type(na.Type.INT32.value)
    assert builder.is_empty()

    with pytest.raises(RuntimeError, match="CArrayBuilder is already initialized"):
        builder.init_from_type(na.Type.INT32.value)

    with pytest.raises(RuntimeError, match="CArrayBuilder is already initialized"):
        builder.init_from_schema(na.c_schema(na.int32()))


def test_c_array_from_pybuffer_uint8():
    data = b"abcdefg"
    c_array = na.c_array(data)
    assert c_array.length == len(data)
    assert c_array.null_count == 0
    assert c_array.offset == 0
    assert c_schema_view(c_array.schema).type == "uint8"

    c_array_view = c_array.view()
    assert list(c_array_view.buffer(1)) == list(data)


def test_c_array_from_pybuffer_string():
    data = b"abcdefg"
    buffer = na.c_buffer(data)._set_format("c")
    c_array = na.c_array(buffer)
    assert c_array.length == len(data)
    assert c_array.null_count == 0
    assert c_array.offset == 0
    assert c_schema_view(c_array.schema).type == "int8"

    c_array_view = c_array.view()
    assert list(c_array_view.buffer(1)) == list(data)


def test_c_array_from_pybuffer_fixed_size_binary():
    items = [b"abcd", b"efgh", b"ijkl"]
    packed = b"".join(items)
    buffer = na.c_buffer(packed)._set_format("4s")

    c_array = na.c_array(buffer)
    assert c_array.length == len(items)
    assert c_array.null_count == 0
    assert c_array.offset == 0
    assert c_schema_view(c_array.schema).type == "fixed_size_binary"
    assert c_schema_view(c_array.schema).fixed_size == 4

    c_array_view = c_array.view()
    assert list(c_array_view.buffer(1)) == items


def test_c_array_from_pybuffer_numpy():
    np = pytest.importorskip("numpy")

    data = np.array([1, 2, 3], dtype=np.int32)
    c_array = na.c_array(data)
    assert c_array.length == len(data)
    assert c_array.null_count == 0
    assert c_array.offset == 0
    assert c_schema_view(c_array.schema).type == "int32"

    c_array_view = c_array.view()
    assert list(c_array_view.buffer(1)) == list(data)


def test_c_array_from_iterable_empty():
    empty_string = na.c_array([], na.string())
    assert empty_string.length == 0
    assert empty_string.null_count == 0
    assert empty_string.offset == 0
    assert empty_string.n_buffers == 3

    array_view = empty_string.view()
    assert len(array_view.buffer(0)) == 0
    assert len(array_view.buffer(1)) == 0
    assert len(array_view.buffer(2)) == 0


def test_c_array_from_iterable_string():
    string = na.c_array(["abc", None, "defg"], na.string())
    assert string.length == 3
    assert string.null_count == 1

    array_view = string.view()
    assert len(array_view.buffer(0)) == 1
    assert len(array_view.buffer(1)) == 4
    assert len(array_view.buffer(2)) == 7

    # Check an item that is not a str()
    with pytest.raises(ValueError):
        na.c_array([b"1234"], na.string())


def test_c_array_from_iterable_bytes():
    string = na.c_array([b"abc", None, b"defg"], na.binary())
    assert string.length == 3
    assert string.null_count == 1

    array_view = string.view()
    assert len(array_view.buffer(0)) == 1
    assert len(array_view.buffer(1)) == 4
    assert len(array_view.buffer(2)) == 7

    with pytest.raises(ValueError):
        na.c_array(["1234"], na.binary())

    buf_not_bytes = na.c_buffer([1, 2, 3], na.int32())
    with pytest.raises(ValueError, match="Can't append buffer with itemsize != 1"):
        na.c_array([buf_not_bytes], na.binary())

    np = pytest.importorskip("numpy")
    buf_2d = np.ones((2, 2))
    with pytest.raises(ValueError, match="Can't append buffer with dimensions != 1"):
        na.c_array([buf_2d], na.binary())


def test_c_array_from_iterable_non_empty_nullable_without_nulls():
    c_array = na.c_array([1, 2, 3], na.int32())
    assert c_array.length == 3
    assert c_array.null_count == 0

    view = c_array.view()
    assert list(view.buffer(0)) == []
    assert list(view.buffer(1)) == [1, 2, 3]


def test_c_array_from_iterable_non_empty_non_nullable():
    c_array = na.c_array([1, 2, 3], na.int32(nullable=False))
    assert c_array.length == 3
    assert c_array.null_count == 0

    view = c_array.view()
    assert list(view.buffer(0)) == []
    assert list(view.buffer(1)) == [1, 2, 3]


def test_c_array_from_iterable_int_with_nulls():
    c_array = na.c_array([1, None, 3], na.int32())
    assert c_array.length == 3
    assert c_array.null_count == 1

    view = c_array.view()
    assert list(view.buffer(0).elements()) == [True, False, True] + [False] * 5
    assert list(view.buffer(1)) == [1, 0, 3]


def test_c_array_from_iterable_float_with_nulls():
    c_array = na.c_array([1, None, 3], na.float64())