import atexit
import os
import platform
import random
import shutil
import subprocess
import tempfile
import textwrap
from pathlib import Path, PurePath, PurePosixPath
from tabnanny import check

import pytest
import toml

from cibuildwheel.docker_container import DockerContainer
from cibuildwheel.environment import EnvironmentAssignmentBash

# Test utilities

# for these tests we use manylinux2014 images, because they're available on
# multi architectures and include python3.8
pm = platform.machine()
if pm == "x86_64":
    DEFAULT_IMAGE = "quay.io/pypa/manylinux2014_x86_64:2020-05-17-2f8ac3b"
elif pm == "aarch64":
    DEFAULT_IMAGE = "quay.io/pypa/manylinux2014_aarch64:2020-05-17-2f8ac3b"
elif pm == "ppc64le":
    DEFAULT_IMAGE = "quay.io/pypa/manylinux2014_ppc64le:2020-05-17-2f8ac3b"
elif pm == "s390x":
    DEFAULT_IMAGE = "quay.io/pypa/manylinux2014_s390x:2020-05-17-2f8ac3b"
else:
    DEFAULT_IMAGE = ""


@pytest.fixture(params=["docker", "podman"])
def container_engine(request):
    if request.param == "docker" and not request.config.getoption("--run-docker"):
        pytest.skip("need --run-docker option to run")
    if request.param == "podman" and not request.config.getoption("--run-podman"):
        pytest.skip("need --run-podman option to run")
    return request.param


# Tests


def test_simple(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        assert container.call(["echo", "hello"], capture_output=True) == "hello\n"


def test_no_lf(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        assert container.call(["printf", "hello"], capture_output=True) == "hello"


def test_debug_info(container_engine):
    container = DockerContainer(container_engine=container_engine, docker_image=DEFAULT_IMAGE)
    print(container.debug_info())
    with container:
        pass


def test_environment(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        assert (
            container.call(
                ["sh", "-c", "echo $TEST_VAR"], env={"TEST_VAR": "1"}, capture_output=True
            )
            == "1\n"
        )


def test_cwd(container_engine):
    with DockerContainer(
        container_engine=container_engine,
        docker_image=DEFAULT_IMAGE,
        cwd="/cibuildwheel/working_directory",
    ) as container:
        assert container.call(["pwd"], capture_output=True) == "/cibuildwheel/working_directory\n"
        assert container.call(["pwd"], capture_output=True, cwd="/opt") == "/opt\n"


def test_container_removed(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        docker_containers_listing = subprocess.run(
            f"{container.container_engine} container ls",
            shell=True,
            check=True,
            stdout=subprocess.PIPE,
            universal_newlines=True,
        ).stdout
        assert container.name is not None
        assert container.name in docker_containers_listing
        old_container_name = container.name

    docker_containers_listing = subprocess.run(
        f"{container.container_engine} container ls",
        shell=True,
        check=True,
        stdout=subprocess.PIPE,
        universal_newlines=True,
    ).stdout
    assert old_container_name not in docker_containers_listing


def test_large_environment(container_engine):
    # max environment variable size is 128kB
    long_env_var_length = 127 * 1024
    large_environment = {
        "a": "0" * long_env_var_length,
        "b": "0" * long_env_var_length,
        "c": "0" * long_env_var_length,
        "d": "0" * long_env_var_length,
    }

    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        # check the length of d
        assert (
            container.call(["sh", "-c", "echo ${#d}"], env=large_environment, capture_output=True)
            == f"{long_env_var_length}\n"
        )


def test_binary_output(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        # note: the below embedded snippets are in python2

        # check that we can pass though arbitrary binary data without erroring
        container.call(
            [
                "/usr/bin/python2",
                "-c",
                textwrap.dedent(
                    """
                    import sys
                    sys.stdout.write(''.join(chr(n) for n in range(0, 256)))
                    """
                ),
            ]
        )

        # check that we can capture arbitrary binary data
        output = container.call(
            [
                "/usr/bin/python2",
                "-c",
                textwrap.dedent(
                    """
                    import sys
                    sys.stdout.write(''.join(chr(n % 256) for n in range(0, 512)))
                    """
                ),
            ],
            capture_output=True,
        )

        data = bytes(output, encoding="utf8", errors="surrogateescape")

        for i in range(512):
            assert data[i] == i % 256

        # check that environment variables can carry binary data, except null characters
        # (https://www.gnu.org/software/libc/manual/html_node/Environment-Variables.html)
        binary_data = bytes(n for n in range(1, 256))
        binary_data_string = str(binary_data, encoding="utf8", errors="surrogateescape")
        output = container.call(
            ["python2", "-c", 'import os, sys; sys.stdout.write(os.environ["TEST_VAR"])'],
            env={"TEST_VAR": binary_data_string},
            capture_output=True,
        )
        assert output == binary_data_string


def test_file_operation(tmp_path: Path, container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        # test copying a file in
        test_binary_data = bytes(random.randrange(256) for _ in range(1000))
        original_test_file = tmp_path / "test.dat"
        original_test_file.write_bytes(test_binary_data)

        dst_file = PurePath("/tmp/test.dat")

        container.copy_into(original_test_file, dst_file)

        output = container.call(["cat", dst_file], capture_output=True)
        assert test_binary_data == bytes(output, encoding="utf8", errors="surrogateescape")


def test_dir_operations(tmp_path: Path, container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        test_binary_data = bytes(random.randrange(256) for _ in range(1000))
        original_test_file = tmp_path / "test.dat"
        original_test_file.write_bytes(test_binary_data)

        # test copying a dir in
        test_dir = tmp_path / "test_dir"
        test_dir.mkdir()
        test_file = test_dir / "test.dat"
        shutil.copyfile(original_test_file, test_file)

        dst_dir = PurePosixPath("/tmp/test_dir")
        dst_file = dst_dir / "test.dat"
        container.copy_into(test_dir, dst_dir)

        output = container.call(["cat", dst_file], capture_output=True)
        assert test_binary_data == bytes(output, encoding="utf8", errors="surrogateescape")

        # test glob
        assert container.glob(dst_dir, "*.dat") == [dst_file]

        # test copy dir out
        new_test_dir = tmp_path / "test_dir_new"
        container.copy_out(dst_dir, new_test_dir)

        assert test_binary_data == (new_test_dir / "test.dat").read_bytes()


def test_environment_executor(container_engine):
    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        assignment = EnvironmentAssignmentBash("TEST=$(echo 42)")
        assert assignment.evaluated_value({}, container.environment_executor) == "42"


def test_podman_vfs(container_engine, tmp_path: Path, monkeypatch):
    # Tests podman VFS, for the podman in docker use-case
    if container_engine != "podman":
        pytest.skip("podman is the only supported container engine for this test")

    # create the VFS configuration
    vfs_path = tmp_path / "podman_vfs"
    vfs_path.mkdir()

    # This requires that we write configuration files and point to them
    # with environment variables before we run podman
    # https://github.com/containers/common/blob/main/docs/containers.conf.5.md
    vfs_containers_conf_data = {
        "containers": {
            "default_capabilities": [
                "CHOWN",
                "DAC_OVERRIDE",
                "FOWNER",
                "FSETID",
                "KILL",
                "NET_BIND_SERVICE",
                "SETFCAP",
                "SETGID",
                "SETPCAP",
                "SETUID",
                "SYS_CHROOT",
            ]
        },
        "engine": {"cgroup_manager": "cgroupfs", "events_logger": "file"},
    }
    # https://github.com/containers/storage/blob/main/docs/containers-storage.conf.5.md
    storage_root = vfs_path / ".local/share/containers/vfs-storage"
    run_root = vfs_path / ".local/share/containers/vfs-runroot"
    storage_root.mkdir(parents=True, exist_ok=True)
    run_root.mkdir(parents=True, exist_ok=True)
    vfs_containers_storage_conf_data = {
        "storage": {
            "driver": "vfs",
            "graphroot": os.fspath(storage_root),
            "runroot": os.fspath(run_root),
            "rootless_storage_path": os.fspath(storage_root),
            "options": {
                # "remap-user": "containers",
                "aufs": {"mountopt": "rw"},
                "overlay": {"mountopt": "rw", "force_mask": "shared"},
                # "vfs": {"ignore_chown_errors": "true"},
            },
        }
    }

    vfs_containers_conf_fpath = vfs_path / "temp_vfs_containers.conf"
    vfs_containers_storage_conf_fpath = vfs_path / "temp_vfs_containers_storage.conf"
    with open(vfs_containers_conf_fpath, "w") as file:
        toml.dump(vfs_containers_conf_data, file)

    with open(vfs_containers_storage_conf_fpath, "w") as file:
        toml.dump(vfs_containers_storage_conf_data, file)

    monkeypatch.setenv("CONTAINERS_CONF", str(vfs_containers_conf_fpath))
    monkeypatch.setenv("CONTAINERS_STORAGE_CONF", str(vfs_containers_storage_conf_fpath))

    with DockerContainer(
        container_engine=container_engine, docker_image=DEFAULT_IMAGE
    ) as container:
        # test running a command
        assert container.call(["echo", "hello"], capture_output=True) == "hello\n"

        # test copying a file into the container
        (tmp_path / "some_file.txt").write_text("1234")
        container.copy_into(tmp_path / "some_file.txt", PurePosixPath("some_file.txt"))
        assert container.call(["cat", "some_file.txt"], capture_output=True) == "1234"

    # Clean up

    # When using the VFS, user is not given write permissions by default in
    # new directories. As a workaround we use 'podman unshare' to delete them
    # as UID 0. The reason why permission errors occur on podman is documented
    # in https://podman.io/blogs/2018/10/03/podman-remove-content-homedir.html
    subprocess.run(["podman", "unshare", "rm", "-rf", vfs_path], check=True)