# -*- coding: utf-8 -*-

# Copyright © Cloud Linux GmbH & Cloud Linux Software, Inc 2010-2019 All Rights Reserved
#
# Licensed under CLOUD LINUX LICENSE AGREEMENT
# http://cloudlinux.com/docs/LICENSE.TXT

from __future__ import print_function
from __future__ import division
from __future__ import absolute_import
import json
import os
import pwd

from clselect.utils import check_call, list_dirs, run_command_full
from .interpreters import Interpreter


DEFAULT_PREFIX = 'nodevenv'
NODEVENV_BIN = os.path.join(os.path.dirname(__file__), 'nodevenv.py')
PYTHON_PATH = '/opt/cloudlinux/venv/bin/python3'
APP_CONFIG = 'package.json'


class Environment(object):

    def __init__(self, name, user=None, prefix=None):
        self.name = name
        if user:
            self.user = user
        else:
            self.user = pwd.getpwuid(os.getuid()).pw_name
        if prefix is None:
            self.prefix = DEFAULT_PREFIX
        else:
            self.prefix = prefix
        self.path = os.path.join(_abs_prefix(self.user, self.prefix), name)
        self._interpreter = None
        self._npm = None
        self.interpreter_name = 'node' + name

    def __repr__(self):
        return ("%s.%s(name='%s', user='%s', prefix='%s')" % (
            self.__class__.__module__, self.__class__.__name__,
            self.name, self.user, self.prefix))

    def _demote(self):
        user_pwd = pwd.getpwnam(self.user)

        def func():
            os.setgid(user_pwd.pw_gid)
            os.setuid(user_pwd.pw_uid)
            os.environ['USER'] = self.user
            os.environ['HOME'] = user_pwd.pw_dir

        return func

    def as_dict(self, key=None):
        e = {
            'name': self.name,
            'interpreter': self.interpreter(),
        }
        if key:
            del e[key]
            return {getattr(self, key): e}
        return e

    def as_deepdict(self, key=None):
        e = {
            'name': self.name,
            'interpreter': self.interpreter().as_dict(),
        }
        if key:
            del e[key]
            return {getattr(self, key): e}
        return e

    def create(self, interpreter, destroy_first=False):
        args = [
            PYTHON_PATH, NODEVENV_BIN,
            '--node', interpreter.binary,
        ]
        if destroy_first:
            args.append('--recreate-bin')
        args.append(self.path)
        kwargs = {'preexec_fn': self._demote()}
        if os.getuid() == 0:
            args = ['/bin/cagefs_enter'] + args
        check_call(*args, **kwargs)

    def destroy(self):
        check_call('/bin/rm', '-r', '--interactive=never', self.path,
                   preexec_fn=self._demote())

    def exists(self):
        return os.path.exists(self.path)

    def interpreter(self):
        if not self._interpreter:
            self._interpreter = Interpreter(prefix=self.path)
        return self._interpreter

    def npm(self):
        if not self._npm:
            self._npm = os.path.join(self.path, 'bin', 'npm')
        return self._npm

    def extension_install(self, extension='-', cwd=None):
        """
        Install nodejs extension
        :param cwd: current working directory for npm (it's full path to app root by default)
        :param extension: name and version of extension
        :return: None
        """
        # git is need for npm install from git repositories
        # we didn't add git to cagefs, because we use git from cpanel
        command = (self.npm(), 'install')
        # extension is defined
        if extension != '-':
            command += (extension,)
        # npm takes list of extensions from package.json if extension is '-'
        else:
            config_path = os.path.join(cwd, APP_CONFIG)
            if not os.path.isfile(config_path):
                # package.json is absent
                return 0
        # command sample
        # npm install <module>@<version> <git_path_to_repository> ...
        check_call(args=command, preexec_fn=self._demote(), cwd=cwd)

    def extension_install_single_call(self, extensions_list):
        """
        Install nodejs extension
        :param extensions_list: name and version of extension
        :return: None
        """
        command = [self.npm(), 'install']
        command.extend(extensions_list)
        # npm install <module1>@<version1> <module2>@<version2> ...
        ret_code, _, _ = run_command_full(command, preexec_fn=self._demote())
        return ret_code

    def extension_update(self, extension):
        raise NotImplementedError("It's not used for nodejs selector")

    def extension_uninstall(self, extension):
        raise NotImplementedError("It's not used for nodejs selector")

    def extensions(self):
        """
        Retrieves extensions dictionary for this virtual environment
        :return: Extensions list.
            Example:
                [u'xpath@0.0.27', u'https://github.com/visionmedia/express']
        """
        # get path to current virtual nodejs environment
        cwd = os.path.split(os.path.split(self.npm())[0])[0]
        # npm list --json
        _, output, _ = run_command_full([self.npm(), 'list', '--json'], preexec_fn=self._demote(), cwd=cwd)
        if output.strip():
            data = json.loads(output)
        else:
            data = {}
        extensions = data.get('dependencies', {})
        # extensions example:
        #  {u'express': {u'version': u'4.16.3', u'from': u'express@^4.15.3', .... },
        #   u'express_new': {u'version': u'4.16.3', u'from': u'git+https://github.com/visionmedia/express.git', ....},
        #   u'request': {u'required': u'^2.81.0', u'missing': True},
        #   u'body-parser': {u'required': u'^1.17.2', u'missing': True}
        #  }
        result = []
        for name, info in extensions.items():
            # module is missing or has no needed attributes - pass it
            if info.get('missing', False) or 'from' not in info or 'version' not in info:
                continue
            if info['from'].startswith('git+'):
                # extension from git
                result.append(info['from'])
            else:
                # extension from standard npm repo
                result.append('%s@%s' % (name, info['version']))
        return result


def _abs_prefix(user=None, prefix=None):
    if not prefix:
        prefix = DEFAULT_PREFIX
    if user:
        return os.path.join(pwd.getpwnam(user).pw_dir, prefix)
    else:
        return os.path.join(pwd.getpwuid(os.getuid()).pw_dir, prefix)


def environments(user=None, prefix=None):
    venv_path = _abs_prefix(user, prefix)
    try:
        env_list = list_dirs(venv_path)
    except OSError:
        return []
    envs = []
    for env_name in env_list:
        envs.append(Environment(env_name, user, prefix))
    return envs


def environments_dict(key, user=None, prefix=None):
    return dict(list(e.as_dict(key=key).items()) for e in environments(user, prefix))


def environments_deepdict(key, user=None, prefix=None):
    return dict(list(e.as_deepdict(key=key).items())
                for e in environments(user, prefix))