"""
Package containing all pip commands
"""

import importlib
from collections import namedtuple
from typing import Any, Dict, Optional

from pip._internal.cli.base_command import Command

CommandInfo = namedtuple("CommandInfo", "module_path, class_name, summary")

# This dictionary does a bunch of heavy lifting for help output:
# - Enables avoiding additional (costly) imports for presenting `--help`.
# - The ordering matters for help display.
#
# Even though the module path starts with the same "pip._internal.commands"
# prefix, the full path makes testing easier (specifically when modifying
# `commands_dict` in test setup / teardown).
commands_dict: Dict[str, CommandInfo] = {
    "install": CommandInfo(
        "pip._internal.commands.install",
        "InstallCommand",
        "Install packages.",
    ),
    "download": CommandInfo(
        "pip._internal.commands.download",
        "DownloadCommand",
        "Download packages.",
    ),
    "uninstall": CommandInfo(
        "pip._internal.commands.uninstall",
        "UninstallCommand",
        "Uninstall packages.",
    ),
    "freeze": CommandInfo(
        "pip._internal.commands.freeze",
        "FreezeCommand",
        "Output installed packages in requirements format.",
    ),
    "inspect": CommandInfo(
        "pip._internal.commands.inspect",
        "InspectCommand",
        "Inspect the python environment.",
    ),
    "list": CommandInfo(
        "pip._internal.commands.list",
        "ListCommand",
        "List installed packages.",
    ),
    "show": CommandInfo(
        "pip._internal.commands.show",
        "ShowCommand",
        "Show information about installed packages.",
    ),
    "check": CommandInfo(
        "pip._internal.commands.check",
        "CheckCommand",
        "Verify installed packages have compatible dependencies.",
    ),
    "config": CommandInfo(
        "pip._internal.commands.configuration",
        "ConfigurationCommand",
        "Manage local and global configuration.",
    ),
    "search": CommandInfo(
        "pip._internal.commands.search",
        "SearchCommand",
        "Search PyPI for packages.",
    ),
    "cache": CommandInfo(
        "pip._internal.commands.cache",
        "CacheCommand",
        "Inspect and manage pip's wheel cache.",
    ),
    "index": CommandInfo(
        "pip._internal.commands.index",
        "IndexCommand",
        "Inspect information available from package indexes.",
    ),
    "wheel": CommandInfo(
        "pip._internal.commands.wheel",
        "WheelCommand",
        "Build wheels from your requirements.",
    ),
    "hash": CommandInfo(
        "pip._internal.commands.hash",
        "HashCommand",
        "Compute hashes of package archives.",
    ),
    "completion": CommandInfo(
        "pip._internal.commands.completion",
        "CompletionCommand",
        "A helper command used for command completion.",
    ),
    "debug": CommandInfo(
        "pip._internal.commands.debug",
        "DebugCommand",
        "Show information useful for debugging.",
    ),
    "help": CommandInfo(
        "pip._internal.commands.help",
        "HelpCommand",
        "Show help for commands.",
    ),
}


def create_command(name: str, **kwargs: Any) -> Command:
    """
    Create an instance of the Command class with the given name.
    """
    module_path, class_name, summary = commands_dict[name]
    module = importlib.import_module(module_path)
    command_class = getattr(module, class_name)
    command = command_class(name=name, summary=summary, **kwargs)

    return command


def get_similar_commands(name: str) -> Optional[str]:
    """Command name auto-correct."""
    from difflib import get_close_matches

    name = name.lower()

    close_commands = get_close_matches(name, commands_dict.keys())

    if close_commands:
        return close_commands[0]
    else:
        return None

import urllib.parse


class PackageIndex:
    """Represents a Package Index and provides easier access to endpoints"""

    __slots__ = ["url", "netloc", "simple_url", "pypi_url", "file_storage_domain"]

    def __init__(self, url: str, file_storage_domain: str) -> None:
        super().__init__()
        self.url = url
        self.netloc = urllib.parse.urlsplit(url).netloc
        self.simple_url = self._url_for_path("simple")
        self.pypi_url = self._url_for_path("pypi")

        # This is part of a temporary hack used to block installs of PyPI
        # packages which depend on external urls only necessary until PyPI can
        # block such packages themselves
        self.file_storage_domain = file_storage_domain

    def _url_for_path(self, path: str) -> str:
        return urllib.parse.urljoin(self.url, path)


PyPI = PackageIndex("https://pypi.org/", file_storage_domain="files.pythonhosted.org")
TestPyPI = PackageIndex(
    "https://test.pypi.org/", file_storage_domain="test-files.pythonhosted.org"
)

from optparse import Values
from typing import List

from pip._internal.cli.base_command import Command
from pip._internal.cli.status_codes import SUCCESS
from pip._internal.exceptions import CommandError


class HelpCommand(Command):
    """Show help for commands"""

    usage = """
      %prog <command>"""
    ignore_require_venv = True

    def run(self, options: Values, args: List[str]) -> int:
        from pip._internal.commands import (
            commands_dict,
            create_command,
            get_similar_commands,
        )

        try:
            # 'pip help' with no args is handled by pip.__init__.parseopt()
            cmd_name = args[0]  # the command we need help for
        except IndexError:
            return SUCCESS

        if cmd_name not in commands_dict:
            guess = get_similar_commands(cmd_name)

            msg = [f'unknown command "{cmd_name}"']
            if guess:
                msg.append(f'maybe you meant "{guess}"')

            raise CommandError(" - ".join(msg))

        command = create_command(cmd_name)
        command.parser.print_help()

        return SUCCESS