# -----------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for
# license information.
# -----------------------------------------------------------------------------

import os
import json
import re
import zipfile

from knack.util import CLIError

from azdev.utilities import EXTENSION_PREFIX


WHEEL_INFO_RE = re.compile(
    r"""^(?P<namever>(?P<name>.+?)(-(?P<ver>\d.+?))?)
    ((-(?P<build>\d.*?))?-(?P<pyver>.+?)-(?P<abi>.+?)-(?P<plat>.+?)
    \.whl|\.dist-info)$""",
    re.VERBOSE).match


def _get_extension_modname(ext_dir):
    # Modification of https://github.com/Azure/azure-cli/blob/dev/src/azure-cli-core/azure/cli/core/extension.py#L153
    pos_mods = [n for n in os.listdir(ext_dir)
                if n.startswith(EXTENSION_PREFIX) and os.path.isdir(os.path.join(ext_dir, n))]
    if len(pos_mods) != 1:
        raise AssertionError("Expected 1 module to load starting with "
                             "'{}': got {}".format(EXTENSION_PREFIX, pos_mods))
    return pos_mods[0]


def _get_azext_metadata(ext_dir):
    # Modification of https://github.com/Azure/azure-cli/blob/dev/src/azure-cli-core/azure/cli/core/extension.py#L109
    AZEXT_METADATA_FILENAME = 'azext_metadata.json'
    azext_metadata = None
    ext_modname = _get_extension_modname(ext_dir=ext_dir)
    azext_metadata_filepath = os.path.join(ext_dir, ext_modname, AZEXT_METADATA_FILENAME)
    if os.path.isfile(azext_metadata_filepath):
        with open(azext_metadata_filepath) as f:
            azext_metadata = json.load(f)
    return azext_metadata


def get_ext_metadata(ext_dir, ext_file, ext_name):
    # Modification of https://github.com/Azure/azure-cli/blob/dev/src/azure-cli-core/azure/cli/core/extension.py#L89
    WHL_METADATA_FILENAME = 'metadata.json'
    with zipfile.ZipFile(ext_file, 'r') as zip_ref:
        zip_ref.extractall(ext_dir)
    metadata = {}
    dist_info_dirs = [f for f in os.listdir(ext_dir) if f.endswith('.dist-info')]
    azext_metadata = _get_azext_metadata(ext_dir)
    if azext_metadata:
        metadata.update(azext_metadata)
    for dist_info_dirname in dist_info_dirs:
        parsed_dist_info_dir = WHEEL_INFO_RE(dist_info_dirname)
        if parsed_dist_info_dir and parsed_dist_info_dir.groupdict().get('name') == ext_name.replace('-', '_'):
            whl_metadata_filepath = os.path.join(ext_dir, dist_info_dirname, WHL_METADATA_FILENAME)
            if os.path.isfile(whl_metadata_filepath):
                with open(whl_metadata_filepath) as f:
                    metadata.update(json.load(f))
    return metadata


def get_whl_from_url(url, filename, tmp_dir, whl_cache=None):
    if not whl_cache:
        whl_cache = {}
    if url in whl_cache:
        return whl_cache[url]
    import requests
    r = requests.get(url, stream=True, timeout=10)
    try:
        assert r.status_code == 200, "Request to {} failed with {}".format(url, r.status_code)
    except AssertionError:
        raise CLIError("unable to download (status code {}): {}".format(r.status_code, url))
    ext_file = os.path.join(tmp_dir, filename)
    with open(ext_file, 'wb') as f:
        for chunk in r.iter_content(chunk_size=1024):
            if chunk:  # ignore keep-alive new chunks
                f.write(chunk)
    whl_cache[url] = ext_file
    return ext_file


def get_pkg_info_from_pkg_metafile(pkg_info_file):
    mod_info = {}
    with open(pkg_info_file, "r", encoding="utf-8") as f:
        for line in f:
            if line.startswith("Name:"):
                pkg_name = line.split(":")[-1].strip()
                mod_info["pkg_name"] = pkg_name
            if line.startswith("Version:"):
                pkg_version = line.split(":")[-1].strip()
                mod_info["pkg_version"] = pkg_version
    return mod_info