# mautrix-signal - A Matrix-Signal puppeting bridge
# Copyright (C) 2020 Tulir Asokan
#
# 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 <https://www.gnu.org/licenses/>.
from typing import Awaitable, Dict, TYPE_CHECKING
import logging
import asyncio
import json

from aiohttp import web

from mausignald.types import Address, Account
from mausignald.errors import LinkingTimeout
from mautrix.types import UserID
from mautrix.util.logging import TraceLogger

from .. import user as u

if TYPE_CHECKING:
    from ..__main__ import SignalBridge


class ProvisioningAPI:
    log: TraceLogger = logging.getLogger("mau.web.provisioning")
    app: web.Application
    bridge: 'SignalBridge'

    def __init__(self, bridge: 'SignalBridge', shared_secret: str) -> None:
        self.bridge = bridge
        self.app = web.Application()
        self.shared_secret = shared_secret
        self.app.router.add_get("/api/whoami", self.status)
        self.app.router.add_options("/api/link", self.login_options)
        self.app.router.add_options("/api/link/wait", self.login_options)
        # self.app.router.add_options("/api/register", self.login_options)
        # self.app.router.add_options("/api/register/code", self.login_options)
        # self.app.router.add_options("/api/logout", self.login_options)
        self.app.router.add_post("/api/link", self.link)
        self.app.router.add_post("/api/link/wait", self.link_wait)
        # self.app.router.add_post("/api/register", self.register)
        # self.app.router.add_post("/api/register/code", self.register_code)
        # self.app.router.add_post("/api/logout", self.logout)

    @property
    def _acao_headers(self) -> Dict[str, str]:
        return {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Headers": "Authorization, Content-Type",
            "Access-Control-Allow-Methods": "POST, OPTIONS",
        }

    @property
    def _headers(self) -> Dict[str, str]:
        return {
            **self._acao_headers,
            "Content-Type": "application/json",
        }

    async def login_options(self, _: web.Request) -> web.Response:
        return web.Response(status=200, headers=self._headers)

    def check_token(self, request: web.Request) -> Awaitable['u.User']:
        try:
            token = request.headers["Authorization"]
            token = token[len("Bearer "):]
        except KeyError:
            raise web.HTTPBadRequest(text='{"error": "Missing Authorization header"}',
                                     headers=self._headers)
        except IndexError:
            raise web.HTTPBadRequest(text='{"error": "Malformed Authorization header"}',
                                     headers=self._headers)
        if token != self.shared_secret:
            raise web.HTTPForbidden(text='{"error": "Invalid token"}', headers=self._headers)
        try:
            user_id = request.query["user_id"]
        except KeyError:
            raise web.HTTPBadRequest(text='{"error": "Missing user_id query param"}',
                                     headers=self._headers)

        return u.User.get_by_mxid(UserID(user_id))

    async def status(self, request: web.Request) -> web.Response:
        user = await self.check_token(request)
        data = {
            "permissions": user.permission_level,
            "mxid": user.mxid,
            "signal": None,
        }
        if await user.is_logged_in():
            profile = await self.bridge.signal.get_profile(username=user.username,
                                                           address=Address(number=user.username))
            addr = profile.address if profile else None
            number = addr.number if addr else None
            uuid = addr.uuid if addr else None
            data["signal"] = {
                "number": number or user.username,
                "uuid": str(uuid or user.uuid or ""),
                "name": profile.name if profile else null,
            }
        return web.json_response(data, headers=self._acao_headers)

    async def link(self, request: web.Request) -> web.Response:
        user = await self.check_token(request)

        try:
            data = await request.json()
        except json.JSONDecodeError:
            raise web.HTTPBadRequest(text='{"error": "Malformed JSON"}', headers=self._headers)

        device_name = data.get("device_name", "Mautrix-Signal bridge")
        uri_future = asyncio.Future()

        async def _callback(uri: str) -> None:
            uri_future.set_result(uri)

        async def _link() -> Account:
            account = await self.bridge.signal.link(_callback, device_name=device_name)
            await user.on_signin(account)
            return account

        user.command_status = {
            "action": "Link",
            "task": self.bridge.loop.create_task(_link()),
        }

        return web.json_response({"uri": await uri_future}, headers=self._acao_headers)

    async def link_wait(self, request: web.Request) -> web.Response:
        user = await self.check_token(request)
        if not user.command_status or user.command_status["action"] != "Link":
            raise web.HTTPBadRequest(text='{"error": "No Signal linking started"}',
                                     headers=self._headers)
        try:
            account = await user.command_status["task"]
        except LinkingTimeout:
            raise web.HTTPBadRequest(text='{"error": "Signal linking timed out"}',
                                     headers=self._headers)
        return web.json_response({
            "number": account.username,
            "uuid": str(account.uuid),
        })

    # async def logout(self, request: web.Request) -> web.Response:
    #     user = await self.check_token(request)
    #     await user.()
    #     return web.json_response({}, headers=self._acao_headers)