"""
The MIT License (MIT)

Copyright (c) 2015-2021 Rapptz
Copyright (c) 2021-present Pycord Development

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
"""

from __future__ import annotations

from typing import TYPE_CHECKING, Any, Union

if TYPE_CHECKING:
    from aiohttp import ClientResponse, ClientWebSocketResponse

    try:
        from requests import Response

        _ResponseType = Union[ClientResponse, Response]
    except ModuleNotFoundError:
        _ResponseType = ClientResponse

    from .interactions import Interaction

__all__ = (
    "DiscordException",
    "ClientException",
    "NoMoreItems",
    "GatewayNotFound",
    "ValidationError",
    "HTTPException",
    "Forbidden",
    "NotFound",
    "DiscordServerError",
    "InvalidData",
    "InvalidArgument",
    "LoginFailure",
    "ConnectionClosed",
    "PrivilegedIntentsRequired",
    "InteractionResponded",
    "ExtensionError",
    "ExtensionAlreadyLoaded",
    "ExtensionNotLoaded",
    "NoEntryPointError",
    "ExtensionFailed",
    "ExtensionNotFound",
    "ApplicationCommandError",
    "CheckFailure",
    "ApplicationCommandInvokeError",
    "MissingVoiceDependenciesError",
)


class DiscordException(Exception):
    """Base exception class for pycord

    Ideally speaking, this could be caught to handle any exceptions raised from this library.
    """


class ClientException(DiscordException):
    """Exception that's raised when an operation in the :class:`Client` fails.

    These are usually for exceptions that happened due to user input.
    """


class NoMoreItems(DiscordException):
    """Exception that is raised when an async iteration operation has no more items."""


class GatewayNotFound(DiscordException):
    """An exception that is raised when the gateway for Discord could not be found"""

    def __init__(self):
        message = "The gateway to connect to discord was not found."
        super().__init__(message)


class ValidationError(DiscordException):
    """An Exception that is raised when there is a Validation Error."""


def _flatten_error_dict(d: dict[str, Any], key: str = "") -> dict[str, str]:
    items: list[tuple[str, str]] = []
    for k, v in d.items():
        new_key = f"{key}.{k}" if key else k

        if isinstance(v, dict):
            try:
                _errors: list[dict[str, Any]] = v["_errors"]
            except KeyError:
                items.extend(_flatten_error_dict(v, new_key).items())
            else:
                items.append((new_key, " ".join(x.get("message", "") for x in _errors)))
        else:
            items.append((new_key, v))

    return dict(items)


class HTTPException(DiscordException):
    """Exception that's raised when an HTTP request operation fails.

    Attributes
    ----------
    response: :class:`aiohttp.ClientResponse`
        The response of the failed HTTP request. This is an
        instance of :class:`aiohttp.ClientResponse`. In some cases
        this could also be a :class:`requests.Response`.

    text: :class:`str`
        The text of the error. Could be an empty string.
    status: :class:`int`
        The status code of the HTTP request.
    code: :class:`int`
        The Discord specific error code for the failure.
    """

    def __init__(self, response: _ResponseType, message: str | dict[str, Any] | None):
        self.response: _ResponseType = response
        self.status: int = response.status  # type: ignore
        self.code: int
        self.text: str
        if isinstance(message, dict):
            self.code = message.get("code", 0)
            base = message.get("message", "")
            errors = message.get("errors")
            if errors:
                errors = _flatten_error_dict(errors)
                helpful = "\n".join("In %s: %s" % t for t in errors.items())
                self.text = f"{base}\n{helpful}"
            else:
                self.text = base
        else:
            self.text = message or ""
            self.code = 0

        fmt = "{0.status} {0.reason} (error code: {1})"
        if len(self.text):
            fmt += ": {2}"

        super().__init__(fmt.format(self.response, self.code, self.text))


class Forbidden(HTTPException):
    """Exception that's raised for when status code 403 occurs.

    Subclass of :exc:`HTTPException`
    """


class NotFound(HTTPException):
    """Exception that's raised for when status code 404 occurs.

    Subclass of :exc:`HTTPException`
    """


class DiscordServerError(HTTPException):
    """Exception that's raised for when a 500 range status code occurs.

    Subclass of :exc:`HTTPException`.

    .. versionadded:: 1.5
    """


class InvalidData(ClientException):
    """Exception that's raised when the library encounters unknown
    or invalid data from Discord.
    """


class InvalidArgument(ClientException):
    """Exception that's raised when an argument to a function
    is invalid some way (e.g. wrong value or wrong type).

    This could be considered the parallel of ``ValueError`` and
    ``TypeError`` except inherited from :exc:`ClientException` and thus
    :exc:`DiscordException`.
    """


class LoginFailure(ClientException):
    """Exception that's raised when the :meth:`Client.login` function
    fails to log you in from improper credentials or some other misc.
    failure.
    """


class ConnectionClosed(ClientException):
    """Exception that's raised when the gateway connection is
    closed for reasons that could not be handled internally.

    Attributes
    ----------
    code: :class:`int`
        The close code of the websocket.
    reason: :class:`str`
        The reason provided for the closure.
    shard_id: Optional[:class:`int`]
        The shard ID that got closed if applicable.
    """

    def __init__(
        self,
        socket: ClientWebSocketResponse,
        *,
        shard_id: int | None,
        code: int | None = None,
    ):
        # This exception is just the same exception except
        # reconfigured to subclass ClientException for users
        self.code: int = code or socket.close_code or -1
        # aiohttp doesn't seem to consistently provide close reason
        self.reason: str = ""
        self.shard_id: int | None = shard_id
        super().__init__(f"Shard ID {self.shard_id} WebSocket closed with {self.code}")


class PrivilegedIntentsRequired(ClientException):
    """Exception that's raised when the gateway is requesting privileged intents, but
    they're not ticked in the developer page yet.

    Go to https://discord.com/developers/applications/ and enable the intents
    that are required. Currently, these are as follows:

    - :attr:`Intents.members`
    - :attr:`Intents.presences`
    - :attr:`Intents.message_content`

    Attributes
    ----------
    shard_id: Optional[:class:`int`]
        The shard ID that got closed if applicable.
    """

    def __init__(self, shard_id: int | None):
        self.shard_id: int | None = shard_id
        msg = (
            "Shard ID %s is requesting privileged intents that have not been explicitly"
            " enabled in the developer portal. It is recommended to go to"
            " https://discord.com/developers/applications/ and explicitly enable the"
            " privileged intents within your application's page. If this is not"
            " possible, then consider disabling the privileged intents instead."
        )
        super().__init__(msg % shard_id)


class InteractionResponded(ClientException):
    """Exception that's raised when sending another interaction response using
    :class:`InteractionResponse` when one has already been done before.

    An interaction can only respond once.

    .. versionadded:: 2.0

    Attributes
    ----------
    interaction: :class:`Interaction`
        The interaction that's already been responded to.
    """

    def __init__(self, interaction: Interaction):
        self.interaction: Interaction = interaction
        super().__init__("This interaction has already been responded to before")


class ExtensionError(DiscordException):
    """Base exception for extension related errors.

    This inherits from :exc:`~discord.DiscordException`.

    Attributes
    ----------
    name: :class:`str`
        The extension that had an error.
    """

    def __init__(self, message: str | None = None, *args: Any, name: str) -> None:
        self.name: str = name
        message = message or f"Extension {name!r} had an error."
        # clean-up @everyone and @here mentions
        m = message.replace("@everyone", "@\u200beveryone").replace(
            "@here", "@\u200bhere"
        )
        super().__init__(m, *args)


class ExtensionAlreadyLoaded(ExtensionError):
    """An exception raised when an extension has already been loaded.

    This inherits from :exc:`ExtensionError`
    """

    def __init__(self, name: str) -> None:
        super().__init__(f"Extension {name!r} is already loaded.", name=name)


class ExtensionNotLoaded(ExtensionError):
    """An exception raised when an extension was not loaded.

    This inherits from :exc:`ExtensionError`
    """

    def __init__(self, name: str) -> None:
        super().__init__(f"Extension {name!r} has not been loaded.", name=name)


class NoEntryPointError(ExtensionError):
    """An exception raised when an extension does not have a ``setup`` entry point function.

    This inherits from :exc:`ExtensionError`
    """

    def __init__(self, name: str) -> None:
        super().__init__(f"Extension {name!r} has no 'setup' function.", name=name)


class ExtensionFailed(ExtensionError):
    """An exception raised when an extension failed to load during execution of the module or ``setup`` entry point.

    This inherits from :exc:`ExtensionError`

    Attributes
    ----------
    name: :class:`str`
        The extension that had the error.
    original: :exc:`Exception`
        The original exception that was raised. You can also get this via
        the ``__cause__`` attribute.
    """

    def __init__(self, name: str, original: Exception) -> None:
        self.original: Exception = original
        msg = (
            f"Extension {name!r} raised an error: {original.__class__.__name__}:"
            f" {original}"
        )
        super().__init__(msg, name=name)


class ExtensionNotFound(ExtensionError):
    """An exception raised when an extension is not found.

    This inherits from :exc:`ExtensionError`

    .. versionchanged:: 1.3
        Made the ``original`` attribute always None.

    Attributes
    ----------
    name: :class:`str`
        The extension that had the error.
    """

    def __init__(self, name: str) -> None:
        msg = f"Extension {name!r} could not be found."
        super().__init__(msg, name=name)


class ApplicationCommandError(DiscordException):
    r"""The base exception type for all application command related errors.

    This inherits from :exc:`DiscordException`.

    This exception and exceptions inherited from it are handled
    in a special way as they are caught and passed into a special event
    from :class:`.Bot`\, :func:`.on_command_error`.
    """


class CheckFailure(ApplicationCommandError):
    """Exception raised when the predicates in :attr:`.Command.checks` have failed.

    This inherits from :exc:`ApplicationCommandError`
    """


class ApplicationCommandInvokeError(ApplicationCommandError):
    """Exception raised when the command being invoked raised an exception.

    This inherits from :exc:`ApplicationCommandError`

    Attributes
    ----------
    original: :exc:`Exception`
        The original exception that was raised. You can also get this via
        the ``__cause__`` attribute.
    """

    def __init__(self, e: Exception) -> None:
        self.original: Exception = e
        super().__init__(
            f"Application Command raised an exception: {e.__class__.__name__}: {e}"
        )


class MissingVoiceDependenciesError(RuntimeError, DiscordException):
    """Raised when required voice dependencies are not installed.

    .. note::
        This exception inherits from both :exc:`RuntimeError` and :exc:`DiscordException`.

    Attributes:
        missing: tuple[str, ...]
            The missing dependencies that are required for voice support.
    """

    def __init__(self, missing: tuple[str, ...]) -> None:
        self.missing: tuple[str, ...] = missing
        deps = ", ".join(missing)
        super().__init__(
            f"{deps} {'is' if len(missing) == 1 else 'are'} required for voice support. "
            'Install them with "pip install py-cord[voice]".'
        )
