from __future__ import annotations

import os
import re
from collections.abc import Generator
from io import BytesIO
from pathlib import Path
from typing import Any

import pytest

from PIL import (
    Image,
    ImageFile,
    Jpeg2KImagePlugin,
    UnidentifiedImageError,
    _binary,
    features,
)

from .helper import (
    assert_image_equal,
    assert_image_similar,
    assert_image_similar_tofile,
    skip_unless_feature,
    skip_unless_feature_version,
)

EXTRA_DIR = "Tests/images/jpeg2000"

pytestmark = skip_unless_feature("jpg_2000")


@pytest.fixture
def card() -> Generator[ImageFile.ImageFile, None, None]:
    with Image.open("Tests/images/test-card.png") as im:
        im.load()
    try:
        yield im
    finally:
        im.close()


# OpenJPEG 2.0.0 outputs this debugging message sometimes; we should
# ignore it---it doesn't represent a test failure.
# 'Not enough memory to handle tile data'


def roundtrip(im: Image.Image, **options: Any) -> Image.Image:
    out = BytesIO()
    im.save(out, "JPEG2000", **options)
    out.seek(0)
    with Image.open(out) as im:
        im.load()
    return im


def test_sanity() -> None:
    # Internal version number
    version = features.version_codec("jpg_2000")
    assert version is not None
    assert re.search(r"\d+\.\d+\.\d+$", version)

    with Image.open("Tests/images/test-card-lossless.jp2") as im:
        px = im.load()
        assert px[0, 0] == (0, 0, 0)
        assert im.mode == "RGB"
        assert im.size == (640, 480)
        assert im.format == "JPEG2000"
        assert im.get_format_mimetype() == "image/jp2"


def test_jpf() -> None:
    with Image.open("Tests/images/balloon.jpf") as im:
        assert im.format == "JPEG2000"
        assert im.get_format_mimetype() == "image/jpx"


def test_invalid_file() -> None:
    invalid_file = "Tests/images/flower.jpg"

    with pytest.raises(SyntaxError):
        Jpeg2KImagePlugin.Jpeg2KImageFile(invalid_file)


def test_bytesio(card: ImageFile.ImageFile) -> None:
    with open("Tests/images/test-card-lossless.jp2", "rb") as f:
        data = BytesIO(f.read())
    with Image.open(data) as im:
        im.load()
        assert_image_similar(im, card, 1.0e-3)


# These two test pre-written JPEG 2000 files that were not written with
# PIL (they were made using Adobe Photoshop)


def test_lossless(card: ImageFile.ImageFile, tmp_path: Path) -> None:
    with Image.open("Tests/images/test-card-lossless.jp2") as im:
        im.load()
        outfile = str(tmp_path / "temp_test-card.png")
        im.save(outfile)
    assert_image_similar(im, card, 1.0e-3)


def test_lossy_tiled(card: ImageFile.ImageFile) -> None:
    assert_image_similar_tofile(card, "Tests/images/test-card-lossy-tiled.jp2", 2.0)


def test_lossless_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card)
    assert_image_equal(im, card)


def test_lossy_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, quality_layers=[20])
    assert_image_similar(im, card, 2.0)


def test_tiled_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, tile_size=(128, 128))
    assert_image_equal(im, card)


def test_tiled_offset_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, tile_size=(128, 128), tile_offset=(0, 0), offset=(32, 32))
    assert_image_equal(im, card)


def test_tiled_offset_too_small(card: ImageFile.ImageFile) -> None:
    with pytest.raises(ValueError):
        roundtrip(card, tile_size=(128, 128), tile_offset=(0, 0), offset=(128, 32))


def test_irreversible_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, irreversible=True, quality_layers=[20])
    assert_image_similar(im, card, 2.0)


def test_prog_qual_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, quality_layers=[60, 40, 20], progression="LRCP")
    assert_image_similar(im, card, 2.0)


def test_prog_res_rt(card: ImageFile.ImageFile) -> None:
    im = roundtrip(card, num_resolutions=8, progression="RLCP")
    assert_image_equal(im, card)


@pytest.mark.parametrize("num_resolutions", range(2, 6))
def test_default_num_resolutions(
    card: ImageFile.ImageFile, num_resolutions: int
) -> None:
    d = 1 << (num_resolutions - 1)
    im = card.resize((d - 1, d - 1))
    with pytest.raises(OSError):
        roundtrip(im, num_resolutions=num_resolutions)
    reloaded = roundtrip(im)
    assert_image_equal(im, reloaded)


def test_reduce() -> None:
    with Image.open("Tests/images/test-card-lossless.jp2") as im:
        assert callable(im.reduce)

        im.reduce = 2
        assert im.reduce == 2

        im.load()
        assert im.size == (160, 120)

        im.thumbnail((40, 40))
        assert im.size == (40, 30)


def test_load_dpi() -> None:
    with Image.open("Tests/images/test-card-lossless.jp2") as im:
        assert im.info["dpi"] == (71.9836, 71.9836)

    with Image.open("Tests/images/zero_dpi.jp2") as im:
        assert "dpi" not in im.info


def test_restricted_icc_profile() -> None:
    ImageFile.LOAD_TRUNCATED_IMAGES = True
    try:
        # JPEG2000 image with a restricted ICC profile and a known colorspace
        with Image.open("Tests/images/balloon_eciRGBv2_aware.jp2") as im:
            assert im.mode == "RGB"
    finally:
        ImageFile.LOAD_TRUNCATED_IMAGES = False


@pytest.mark.skipif(
    not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
)
def test_unknown_colorspace() -> None:
    with Image.open(f"{EXTRA_DIR}/file8.jp2") as im:
        im.load()
        assert im.mode == "L"


def test_header_errors() -> None:
    for path in (
        "Tests/images/invalid_header_length.jp2",
        "Tests/images/not_enough_data.jp2",
    ):
        with pytest.raises(UnidentifiedImageError):
            with Image.open(path):
                pass

    with pytest.raises(OSError):
        with Image.open("Tests/images/expected_to_read.jp2"):
            pass


def test_layers_type(card: ImageFile.ImageFile, tmp_path: Path) -> None:
    outfile = str(tmp_path / "temp_layers.jp2")
    for quality_layers in [[100, 50, 10], (100, 50, 10), None]:
        card.save(outfile, quality_layers=quality_layers)

    for quality_layers_str in ["quality_layers", ("100", "50", "10")]:
        with pytest.raises(ValueError):
            card.save(outfile, quality_layers=quality_layers_str)


def test_layers(card: ImageFile.ImageFile) -> None:
    out = BytesIO()
    card.save(out, "JPEG2000", quality_layers=[100, 50, 10], progression="LRCP")
    out.seek(0)

    with Image.open(out) as im:
        im.layers = 1
        im.load()
        assert_image_similar(im, card, 13)

    out.seek(0)
    with Image.open(out) as im:
        im.layers = 3
        im.load()
        assert_image_similar(im, card, 0.4)


@pytest.mark.parametrize(
    "name, args, offset, data",
    (
        ("foo.j2k", {}, 0, b"\xff\x4f"),
        ("foo.jp2", {}, 4, b"jP"),
        (None, {"no_jp2": True}, 0, b"\xff\x4f"),
        ("foo.j2k", {"no_jp2": True}, 0, b"\xff\x4f"),
        ("foo.jp2", {"no_jp2": True}, 0, b"\xff\x4f"),
        ("foo.j2k", {"no_jp2": False}, 0, b"\xff\x4f"),
        ("foo.jp2", {"no_jp2": False}, 4, b"jP"),
        (None, {"no_jp2": False}, 4, b"jP"),
    ),
)
def test_no_jp2(
    card: ImageFile.ImageFile,
    name: str,
    args: dict[str, bool],
    offset: int,
    data: bytes,
) -> None:
    out = BytesIO()
    if name:
        out.name = name
    card.save(out, "JPEG2000", **args)
    out.seek(offset)
    assert out.read(2) == data


def test_mct(card: ImageFile.ImageFile) -> None:
    # Three component
    for val in (0, 1):
        out = BytesIO()
        card.save(out, "JPEG2000", mct=val, no_jp2=True)

        assert out.getvalue()[59] == val
        with Image.open(out) as im:
            assert_image_similar(im, card, 1.0e-3)

    # Single component should have MCT disabled
    for val in (0, 1):
        out = BytesIO()
        with Image.open("Tests/images/16bit.cropped.jp2") as jp2:
            jp2.save(out, "JPEG2000", mct=val, no_jp2=True)

        assert out.getvalue()[53] == 0
        with Image.open(out) as im:
            assert_image_similar(im, jp2, 1.0e-3)


def test_sgnd(tmp_path: Path) -> None:
    outfile = str(tmp_path / "temp.jp2")

    im = Image.new("L", (1, 1))
    im.save(outfile)
    with Image.open(outfile) as reloaded:
        assert reloaded.getpixel((0, 0)) == 0

    im = Image.new("L", (1, 1))
    im.save(outfile, signed=True)
    with Image.open(outfile) as reloaded_signed:
        assert reloaded_signed.getpixel((0, 0)) == 128


@pytest.mark.parametrize("ext", (".j2k", ".jp2"))
def test_rgba(ext: str) -> None:
    # Arrange
    with Image.open("Tests/images/rgb_trns_ycbc" + ext) as im:
        # Act
        im.load()

        # Assert
        assert im.mode == "RGBA"


@pytest.mark.skipif(
    not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
)
@skip_unless_feature_version("jpg_2000", "2.5.1")
def test_cmyk() -> None:
    with Image.open(f"{EXTRA_DIR}/issue205.jp2") as im:
        assert im.mode == "CMYK"
        assert im.getpixel((0, 0)) == (185, 134, 0, 0)


@pytest.mark.parametrize("ext", (".j2k", ".jp2"))
def test_16bit_monochrome_has_correct_mode(ext: str) -> None:
    with Image.open("Tests/images/16bit.cropped" + ext) as im:
        im.load()
        assert im.mode == "I;16"


def test_16bit_monochrome_jp2_like_tiff() -> None:
    with Image.open("Tests/images/16bit.cropped.tif") as tiff_16bit:
        assert_image_similar_tofile(tiff_16bit, "Tests/images/16bit.cropped.jp2", 1e-3)


def test_16bit_monochrome_j2k_like_tiff() -> None:
    with Image.open("Tests/images/16bit.cropped.tif") as tiff_16bit:
        assert_image_similar_tofile(tiff_16bit, "Tests/images/16bit.cropped.j2k", 1e-3)


def test_16bit_j2k_roundtrips() -> None:
    with Image.open("Tests/images/16bit.cropped.j2k") as j2k:
        im = roundtrip(j2k)
        assert_image_equal(im, j2k)


def test_16bit_jp2_roundtrips() -> None:
    with Image.open("Tests/images/16bit.cropped.jp2") as jp2:
        im = roundtrip(jp2)
        assert_image_equal(im, jp2)


def test_issue_6194() -> None:
    with Image.open("Tests/images/issue_6194.j2k") as im:
        assert im.getpixel((5, 5)) == 31


def test_unknown_j2k_mode() -> None:
    with pytest.raises(UnidentifiedImageError):
        with Image.open("Tests/images/unknown_mode.j2k"):
            pass


def test_unbound_local() -> None:
    # prepatch, a malformed jp2 file could cause an UnboundLocalError exception.
    with pytest.raises(UnidentifiedImageError):
        with Image.open("Tests/images/unbound_variable.jp2"):
            pass


def test_parser_feed() -> None:
    # Arrange
    with open("Tests/images/test-card-lossless.jp2", "rb") as f:
        data = f.read()

    # Act
    p = ImageFile.Parser()
    p.feed(data)

    # Assert
    assert p.image is not None
    assert p.image.size == (640, 480)


@pytest.mark.skipif(
    not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
)
@pytest.mark.parametrize("name", ("subsampling_1", "subsampling_2", "zoo1", "zoo2"))
def test_subsampling_decode(name: str) -> None:
    test = f"{EXTRA_DIR}/{name}.jp2"
    reference = f"{EXTRA_DIR}/{name}.ppm"

    with Image.open(test) as im:
        epsilon = 3.0  # for YCbCr images
        with Image.open(reference) as im2:
            width, height = im2.size
            if name[-1] == "2":
                # RGB reference images are downscaled
                epsilon = 3e-3
                width, height = width * 2, height * 2
            expected = im2.resize((width, height), Image.Resampling.NEAREST)
        assert_image_similar(im, expected, epsilon)


@pytest.mark.skipif(
    not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
)
def test_pclr() -> None:
    with Image.open(f"{EXTRA_DIR}/issue104_jpxstream.jp2") as im:
        assert im.mode == "P"
        assert len(im.palette.colors) == 256
        assert im.palette.colors[(255, 255, 255)] == 0

    with Image.open(
        f"{EXTRA_DIR}/147af3f1083de4393666b7d99b01b58b_signal_sigsegv_130c531_6155_5136.jp2"
    ) as im:
        assert im.mode == "P"
        assert len(im.palette.colors) == 139
        assert im.palette.colors[(0, 0, 0, 0)] == 0


def test_comment() -> None:
    with Image.open("Tests/images/comment.jp2") as im:
        assert im.info["comment"] == b"Created by OpenJPEG version 2.5.0"

    # Test an image that is truncated partway through a codestream
    with open("Tests/images/comment.jp2", "rb") as fp:
        b = BytesIO(fp.read(130))
        with Image.open(b) as im:
            pass


def test_save_comment(card: ImageFile.ImageFile) -> None:
    for comment in ("Created by Pillow", b"Created by Pillow"):
        out = BytesIO()
        card.save(out, "JPEG2000", comment=comment)

        with Image.open(out) as im:
            assert im.info["comment"] == b"Created by Pillow"

    out = BytesIO()
    long_comment = b" " * 65531
    card.save(out, "JPEG2000", comment=long_comment)
    with Image.open(out) as im:
        assert im.info["comment"] == long_comment

    with pytest.raises(ValueError):
        card.save(out, "JPEG2000", comment=long_comment + b" ")


@pytest.mark.parametrize(
    "test_file",
    [
        "Tests/images/crash-4fb027452e6988530aa5dabee76eecacb3b79f8a.j2k",
        "Tests/images/crash-7d4c83eb92150fb8f1653a697703ae06ae7c4998.j2k",
        "Tests/images/crash-ccca68ff40171fdae983d924e127a721cab2bd50.j2k",
        "Tests/images/crash-d2c93af851d3ab9a19e34503626368b2ecde9c03.j2k",
    ],
)
def test_crashes(test_file: str) -> None:
    with open(test_file, "rb") as f:
        with Image.open(f) as im:
            # Valgrind should not complain here
            try:
                im.load()
            except OSError:
                pass


@skip_unless_feature_version("jpg_2000", "2.4.0")
def test_plt_marker(card: ImageFile.ImageFile) -> None:
    # Search the start of the codesteam for PLT
    out = BytesIO()
    card.save(out, "JPEG2000", no_jp2=True, plt=True)
    out.seek(0)
    while True:
        marker = out.read(2)
        if not marker:
            pytest.fail("End of stream without PLT")

        jp2_boxid = _binary.i16be(marker)
        if jp2_boxid == 0xFF4F:
            # SOC has no length
            continue
        elif jp2_boxid == 0xFF58:
            # PLT
            return
        elif jp2_boxid == 0xFF93:
            pytest.fail("SOD without finding PLT first")

        hdr = out.read(2)
        length = _binary.i16be(hdr)
        out.seek(length - 2, os.SEEK_CUR)


def test_9bit() -> None:
    with Image.open("Tests/images/9bit.j2k") as im:
        assert im.mode == "I;16"
        assert im.size == (128, 128)