# Copyright (C) 2012 Anaconda, Inc
# SPDX-License-Identifier: BSD-3-Clause
"""Pip-flavored installer."""

import os
import os.path as op
from logging import getLogger

from ...auxlib.compat import Utf8NamedTemporaryFile
from ...base.context import context
from ...common.io import Spinner
from ...env.pip_util import get_pip_installed_packages, pip_subprocess
from ...gateways.connection.session import CONDA_SESSION_SCHEMES

log = getLogger(__name__)


def _pip_install_via_requirements(prefix, specs, args, *_, **kwargs):
    """
    Installs the pip dependencies in specs using a temporary pip requirements file.

    Args
    ----
    prefix: string
      The path to the python and pip executables.

    specs: iterable of strings
      Each element should be a valid pip dependency.
      See: https://pip.pypa.io/en/stable/user_guide/#requirements-files
           https://pip.pypa.io/en/stable/reference/pip_install/#requirements-file-format
    """
    url_scheme = args.file.split("://", 1)[0]
    if url_scheme in CONDA_SESSION_SCHEMES:
        pip_workdir = None
    else:
        try:
            pip_workdir = op.dirname(op.abspath(args.file))
            if not os.access(pip_workdir, os.W_OK):
                pip_workdir = None
        except AttributeError:
            pip_workdir = None
    requirements = None
    try:
        # Generate the temporary requirements file
        requirements = Utf8NamedTemporaryFile(
            mode="w",
            prefix="condaenv.",
            suffix=".requirements.txt",
            dir=pip_workdir,
            delete=False,
        )
        requirements.write("\n".join(specs))
        requirements.close()
        # pip command line...
        # see https://pip.pypa.io/en/stable/cli/pip/#exists-action-option
        pip_cmd = ["install", "-U", "-r", requirements.name, "--exists-action=b"]
        stdout, stderr = pip_subprocess(pip_cmd, prefix, cwd=pip_workdir)
    finally:
        # Win/Appveyor does not like it if we use context manager + delete=True.
        # So we delete the temporary file in a finally block.
        if requirements is not None and op.isfile(requirements.name):
            if "CONDA_TEST_SAVE_TEMPS" not in os.environ:
                os.remove(requirements.name)
            else:
                log.warning(
                    f"CONDA_TEST_SAVE_TEMPS :: retaining pip requirements.txt {requirements.name}"
                )
    return get_pip_installed_packages(stdout)


def install(*args, **kwargs):
    with Spinner(
        "Installing pip dependencies",
        not context.verbose and not context.quiet,
        context.json,
    ):
        return _pip_install_via_requirements(*args, **kwargs)