#!/usr/bin/env python3


# SAT: a jabber client
# Copyright (C) 2009-2026 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""XMPP URI parsing and building tools"""

import urllib.parse

from typing import Literal

# FIXME: basic implementation, need to follow RFC 5122

XmppUriType = Literal["pubsub"] | None


def parse_xmpp_uri(uri: str) -> dict[str, str]:
    """Parse an XMPP URI and return a dict with various information.

    @param uri: URI to parse.
    @return: data depending on the URI where keys can be:
        - "type": one of ("pubsub", ""). Always present.
        - "sub_type": can be "microblog", only used for pubsub for now.
        - "path": XMPP path (JID of the service or entity).
        - "node": node used.
        - "id": ID of the element (item for pubsub).
    @raise ValueError: the scheme is not "xmpp".
    """
    uri_split = urllib.parse.urlsplit(uri)
    if uri_split.scheme != "xmpp":
        raise ValueError("this is not a XMPP URI")

    # XXX: we don't use jid.JID for path as it can be used both in backend and frontend
    # which may use different JID classes
    data: dict[str, str] = {"path": urllib.parse.unquote(uri_split.path)}

    query_end = uri_split.query.find(";")
    if query_end == -1:
        query_type: str | None = None
    else:
        query_type = uri_split.query[:query_end]
        if "=" in query_type:
            raise ValueError("no query type, invalid XMPP URI")

    pairs = urllib.parse.parse_qs(uri_split.geturl(), separator=";")
    for k, v in list(pairs.items()):
        if len(v) != 1:
            raise NotImplementedError("multiple values not managed")
        if k in ("path", "type", "sub_type"):
            raise NotImplementedError("reserved key used in URI, this is not supported")
        data[k] = urllib.parse.unquote(v[0])

    if query_type:
        data["type"] = query_type
    elif "node" in data:
        data["type"] = "pubsub"
    else:
        data["type"] = ""

    if "node" in data:
        if data["node"].startswith("urn:xmpp:microblog:"):
            data["sub_type"] = "microblog"

    return data


def _add_pairs(uri_parts: list[str], pairs: dict[str, str]) -> None:
    """Append ;key=value pairs to a URI parts list.

    Underscores in keys are converted to hyphens.
    """
    for k, v in pairs.items():
        uri_parts.append(
            ";"
            + urllib.parse.quote_plus(k.replace("_", "-").encode("utf-8"))
            + "="
            + urllib.parse.quote_plus(v.encode("utf-8"))
        )


def build_xmpp_uri(
    type_: XmppUriType = None,
    subtype: str | None = None,
    path: str = "",
    **kwargs: str,
) -> str:
    """Build an xmpp: URI.

    @param type_: URI query type (e.g.; "pubsub").
    @param subtype: sub-type hint (e.g. "microblog").
    @param path: XMPP path (JID).
    @param kwargs: additional query parameters
    """
    uri: list[str] = ["xmpp:"]
    uri.append(urllib.parse.quote_plus(path.encode("utf-8")).replace("%40", "@"))

    if type_ is None:
        if kwargs:
            uri.append("?")
            _add_pairs(uri, kwargs)
    elif type_ == "pubsub":
        if subtype == "microblog" and not kwargs.get("node"):
            kwargs["node"] = "urn:xmpp:microblog:0"
        if kwargs:
            uri.append("?")
            _add_pairs(uri, kwargs)
    else:
        raise NotImplementedError(f"{type_!r} URI type is not handled yet")

    return "".join(uri)