# mautrix-signal - A Matrix-Signal puppeting bridge
# Copyright (C) 2022 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 __future__ import annotations

from typing import Awaitable
import base64
import json

from mausignald.errors import UnknownIdentityKey, UnregisteredUserError
from mausignald.types import Address, GroupID, TrustLevel
from mautrix.bridge import RejectMatrixInvite
from mautrix.bridge.commands import SECTION_ADMIN, HelpSection, command_handler
from mautrix.types import (
    ContentURI,
    EventID,
    EventType,
    JoinRule,
    PowerLevelStateEventContent,
    RoomID,
)
from mautrix.util import background_task

from .. import portal as po, puppet as pu
from ..util import normalize_number, user_has_power_level
from .auth import make_qr
from .typehint import CommandEvent
from .util import get_initial_state

try:
    import PIL as _
    import qrcode
except ImportError:
    qrcode = None

SECTION_SIGNAL = HelpSection("Signal actions", 20, "")


async def _get_puppet_from_cmd(evt: CommandEvent) -> pu.Puppet | None:
    try:
        phone = normalize_number("".join(evt.args))
    except Exception:
        await evt.reply(
            f"**Usage:** `$cmdprefix+sp {evt.command} <phone>` "
            "(enter phone number in international format)"
        )
        return None

    puppet: pu.Puppet = await pu.Puppet.get_by_number(phone)
    if not puppet:
        if not evt.sender.username:
            await evt.reply("UUID of user not known")
            return None
        try:
            uuid = await evt.bridge.signal.find_uuid(evt.sender.username, phone)
        except UnregisteredUserError:
            await evt.reply("User not registered")
            return None

        if uuid:
            puppet = await pu.Puppet.get_by_uuid(uuid)
        else:
            await evt.reply("UUID of user not found")
            return None
    return puppet


def _format_safety_number(number: str) -> str:
    line_size = 20
    chunk_size = 5
    return "\n".join(
        " ".join(
            [
                number[chunk : chunk + chunk_size]
                for chunk in range(line, line + line_size, chunk_size)
            ]
        )
        for line in range(0, len(number), line_size)
    )


def _pill(puppet: "pu.Puppet") -> str:
    return f"[{puppet.name}](https://matrix.to/#/{puppet.mxid})"


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Open a private chat portal with a specific phone number",
    help_args="<_phone_>",
)
async def pm(evt: CommandEvent) -> None:
    puppet = await _get_puppet_from_cmd(evt)
    if not puppet:
        return
    portal = await po.Portal.get_by_chat_id(puppet.uuid, receiver=evt.sender.username, create=True)
    if portal.mxid:
        await evt.reply(
            f"You already have a private chat with {puppet.name}: "
            f"[{portal.mxid}](https://matrix.to/#/{portal.mxid})"
        )
        await portal.main_intent.invite_user(portal.mxid, evt.sender.mxid)
        return

    await portal.create_matrix_room(evt.sender, puppet.address)
    await evt.reply(f"Created a portal room with {_pill(puppet)} and invited you to it")


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Join a Signal group with an invite link",
    help_args="<_link_>",
)
async def join(evt: CommandEvent) -> EventID:
    if len(evt.args) == 0:
        return await evt.reply("**Usage:** `$cmdprefix+sp join <invite link>`")
    try:
        resp = await evt.bridge.signal.join_group(evt.sender.username, evt.args[0])
        if resp.pending_admin_approval:
            return await evt.reply(
                f"Successfully requested to join {resp.title}, waiting for admin approval."
            )
        else:
            return await evt.reply(f"Successfully joined {resp.title}")
    except Exception:
        evt.log.exception("Error trying to join group")
        await evt.reply("Failed to join group (see logs for more details)")


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Get the invite link to the current group",
)
async def invite_link(evt: CommandEvent) -> EventID:
    if not evt.is_portal:
        return await evt.reply("This is not a portal room.")
    group = await evt.bridge.signal.get_group(
        evt.sender.username, evt.portal.chat_id, evt.portal.revision
    )
    if not group:
        await evt.reply("Failed to get group info")
    elif not group.invite_link:
        await evt.reply("Invite link not available")
    else:
        await evt.reply(group.invite_link)


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="View the safety number of a specific user",
    help_args="[--qr] [_phone_]",
)
async def safety_number(evt: CommandEvent) -> None:
    show_qr = evt.args and evt.args[0].lower() == "--qr"
    if show_qr:
        if not qrcode:
            await evt.reply("Can't generate QR code: qrcode and/or PIL not installed")
            return
        evt.args = evt.args[1:]
    if len(evt.args) == 0 and evt.portal and evt.portal.is_direct:
        puppet = await evt.portal.get_dm_puppet()
    else:
        puppet = await _get_puppet_from_cmd(evt)
    if not puppet:
        return

    resp = await evt.bridge.signal.get_identities(evt.sender.username, puppet.address)
    if not resp.identities:
        await evt.reply(f"No identities found for {_pill(puppet)}")
        return
    most_recent = resp.identities[0]
    for identity in resp.identities:
        if identity.added > most_recent.added:
            most_recent = identity
    uuid = resp.address.uuid or "unknown"
    await evt.reply(
        f"### {puppet.name}\n\n"
        f"**UUID:** {uuid}  \n"
        f"**Trust level:** {most_recent.trust_level}  \n"
        f"**Safety number:**\n"
        f"```\n{_format_safety_number(most_recent.safety_number)}\n```"
    )
    if show_qr and most_recent.qr_code_data:
        data = base64.b64decode(most_recent.qr_code_data)
        content = await make_qr(evt.main_intent, data, "verification-qr.png")
        await evt.main_intent.send_message(evt.room_id, content)


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Set your Signal profile name",
    help_args="<_name_>",
)
async def set_profile_name(evt: CommandEvent) -> None:
    await evt.bridge.signal.set_profile(evt.sender.username, name=" ".join(evt.args))
    await evt.reply("Successfully updated profile name")


_trust_levels = [x.value for x in TrustLevel]


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Mark another user's safety number as trusted",
    help_args="<_recipient phone_> [_level_] <_safety number_>",
)
async def mark_trusted(evt: CommandEvent) -> EventID:
    if len(evt.args) < 2:
        return await evt.reply(
            "**Usage:** `$cmdprefix+sp mark-trusted <recipient phone> [level] <safety number>`"
        )
    number = normalize_number(evt.args[0])
    remaining_args = evt.args[1:]
    trust_level = TrustLevel.TRUSTED_VERIFIED
    if len(evt.args) > 2 and evt.args[1].upper() in _trust_levels:
        trust_level = TrustLevel(evt.args[1])
        remaining_args = evt.args[2:]
    safety_num = "".join(remaining_args).replace("\n", "")
    if len(safety_num) != 60 or not safety_num.isdecimal():
        return await evt.reply("That doesn't look like a valid safety number")
    try:
        await evt.bridge.signal.trust(
            evt.sender.username,
            Address(number=number),
            safety_number=safety_num,
            trust_level=trust_level,
        )
    except UnknownIdentityKey as e:
        return await evt.reply(f"Failed to mark {number} as {trust_level.human_str}: {e}")
    return await evt.reply(f"Successfully marked {number} as {trust_level.human_str}")


@command_handler(
    needs_admin=False,
    needs_auth=True,
    help_section=SECTION_SIGNAL,
    help_text="Sync data from Signal",
)
async def sync(evt: CommandEvent) -> None:
    await evt.sender.sync()
    await evt.reply("Sync complete")


@command_handler(
    needs_admin=True,
    needs_auth=False,
    help_section=SECTION_ADMIN,
    help_text="Send raw requests to signald",
    help_args="[--user] <type> <_json_>",
)
async def raw(evt: CommandEvent) -> None:
    add_username = False
    while True:
        flag = evt.args[0].lower()
        if flag == "--user":
            add_username = True
        else:
            break
        evt.args = evt.args[1:]
    type = evt.args[0]
    version = "v0"
    if "." in type:
        version, type = type.split(".", 1)
    try:
        args = json.loads(" ".join(evt.args[1:]))
    except json.JSONDecodeError as e:
        await evt.reply(f"JSON decode error: {e}")
        return
    if add_username:
        if version == "v0" or (version == "v1" and type in ("send", "react")):
            args["username"] = evt.sender.username
        else:
            args["account"] = evt.sender.username
    if version:
        args["version"] = version

    try:
        resp_type, resp_data = await evt.bridge.signal._raw_request(type, **args)
    except Exception as e:
        await evt.reply(f"Error sending request: {e}")
    else:
        if resp_data is None:
            await evt.reply(f"Got reply `{resp_type}` with no content")
        else:
            await evt.reply(
                f"Got reply `{resp_type}`:\n\n```json\n{json.dumps(resp_data, indent=2)}\n```"
            )


missing_power_warning = (
    "Warning: The bridge bot ([{bot_mxid}](https://matrix.to/#/{bot_mxid})) does not have "
    "sufficient privileges to change power levels on Matrix. Power level changes will not be "
    "bridged."
)

low_power_warning = (
    "Warning: The bridge bot ([{bot_mxid}](https://matrix.to/#/{bot_mxid})) has a power level "
    "below or equal to 50. Bridged moderator rights are currently hardcoded to PL 50, so the "
    "bridge bot must have a higher level to properly bridge them."
)

meta_power_warning = (
    "Warning: Permissions for changing name, topic and avatar cannot be set separately on Signal. "
    "Changes to those may not be bridged properly, unless the permissions are set to the same "
    "level or lower than state_default."
)


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Create a Signal group for the current Matrix room.",
)
async def create(evt: CommandEvent) -> EventID:
    if evt.portal:
        return await evt.reply("This is already a portal room.")

    title, about, levels, encrypted, avatar_url, join_rule = await get_initial_state(
        evt.az.intent, evt.room_id
    )

    if not title:
        return await evt.reply("Please set a room name before creating a Signal group.")

    portal = po.Portal(
        chat_id=GroupID(""),
        mxid=evt.room_id,
        name=title,
        topic=about or "",
        encrypted=encrypted,
        receiver="",
        avatar_url=avatar_url,
    )
    await warn_missing_power(levels, evt)

    await portal.create_signal_group(evt.sender, levels, join_rule)


@command_handler(
    name="id",
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Get the ID of the Signal chat where this room is bridged.",
)
async def get_id(evt: CommandEvent) -> EventID:
    if evt.portal:
        return await evt.reply(f"This room is bridged to Signal chat ID `{evt.portal.chat_id}`.")
    await evt.reply("This is not a portal room.")


@command_handler(
    needs_auth=True,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Bridge the current Matrix room to the Signal chat with the given ID.",
    help_args="<signal chat ID> [matrix room ID]",
)
async def bridge(evt: CommandEvent) -> EventID:
    if len(evt.args) == 0:
        return await evt.reply(
            "**Usage:** `$cmdprefix+sp bridge <signal chat ID> [matrix room ID]`"
        )
    room_id = RoomID(evt.args[1]) if len(evt.args) > 1 else evt.room_id
    that_this = "This" if room_id == evt.room_id else "That"

    portal = await po.Portal.get_by_mxid(room_id)
    if portal:
        return await evt.reply(f"{that_this} room is already a portal room.")

    if not await user_has_power_level(room_id, evt.az.intent, evt.sender, "bridge"):
        return await evt.reply(f"You do not have the permissions to bridge {that_this} room.")

    portal = await po.Portal.get_by_chat_id(GroupID(evt.args[0]), create=True)
    if portal.mxid:
        has_portal_message = (
            "That Signal chat already has a portal at "
            f"[{portal.mxid}](https://matrix.to/#/{portal.mxid}). "
        )
        if not await user_has_power_level(portal.mxid, evt.az.intent, evt.sender, "unbridge"):
            return await evt.reply(
                f"{has_portal_message}"
                "Additionally, you do not have the permissions to unbridge that room."
            )
        evt.sender.command_status = {
            "next": confirm_bridge,
            "action": "Room bridging",
            "mxid": portal.mxid,
            "bridge_to_mxid": room_id,
            "chat_id": portal.chat_id,
        }
        return await evt.reply(
            f"{has_portal_message}"
            "However, you have the permissions to unbridge that room.\n\n"
            "To delete that portal completely and continue bridging, use "
            "`$cmdprefix+sp delete-and-continue`. To unbridge the portal "
            "without kicking Matrix users, use `$cmdprefix+sp unbridge-and-"
            "continue`. To cancel, use `$cmdprefix+sp cancel`"
        )
    evt.sender.command_status = {
        "next": confirm_bridge,
        "action": "Room bridging",
        "bridge_to_mxid": room_id,
        "chat_id": portal.chat_id,
    }
    return await evt.reply(
        "That Signal chat has no existing portal. To confirm bridging the "
        "chat to this room, use `$cmdprefix+sp continue`"
    )


async def cleanup_old_portal_while_bridging(
    evt: CommandEvent, portal: po.Portal
) -> tuple[bool, Awaitable[None] | None]:
    if not portal.mxid:
        await evt.reply(
            "The portal seems to have lost its Matrix room between you"
            "calling `$cmdprefix+sp bridge` and this command.\n\n"
            "Continuing without touching previous Matrix room..."
        )
        return True, None
    elif evt.args[0] == "delete-and-continue":
        return True, portal.cleanup_portal("Portal deleted (moving to another room)")
    elif evt.args[0] == "unbridge-and-continue":
        return True, portal.cleanup_portal(
            "Room unbridged (portal moving to another room)", puppets_only=True
        )
    else:
        await evt.reply(
            "The chat you were trying to bridge already has a Matrix portal room.\n\n"
            "Please use `$cmdprefix+sp delete-and-continue` or `$cmdprefix+sp unbridge-and-"
            "continue` to either delete or unbridge the existing room (respectively) and "
            "continue with the bridging.\n\n"
            "If you changed your mind, use `$cmdprefix+sp cancel` to cancel."
        )
        return False, None


async def confirm_bridge(evt: CommandEvent) -> EventID | None:
    status = evt.sender.command_status
    try:
        portal = await po.Portal.get_by_chat_id(status["chat_id"])
        bridge_to_mxid = status["bridge_to_mxid"]
    except KeyError:
        evt.sender.command_status = None
        return await evt.reply(
            "Fatal error: chat_id missing from command_status. "
            "This shouldn't happen unless you're messing with the command handler code."
        )

    is_logged_in = await evt.sender.is_logged_in()

    if "mxid" in status:
        ok, coro = await cleanup_old_portal_while_bridging(evt, portal)
        if not ok:
            return None
        elif coro:
            await evt.reply("Cleaning up previous portal room...")
            await coro
    elif portal.mxid:
        evt.sender.command_status = None
        return await evt.reply(
            "The portal seems to have created a Matrix room between you "
            "calling `$cmdprefix+sp bridge` and this command.\n\n"
            "Please start over by calling the bridge command again."
        )
    elif evt.args[0] != "continue":
        return await evt.reply(
            "Please use `$cmdprefix+sp continue` to confirm the bridging or "
            "`$cmdprefix+sp cancel` to cancel."
        )
    evt.sender.command_status = None
    async with portal._create_room_lock:
        await _locked_confirm_bridge(
            evt, portal=portal, room_id=bridge_to_mxid, is_logged_in=is_logged_in
        )


async def _locked_confirm_bridge(
    evt: CommandEvent, portal: po.Portal, room_id: RoomID, is_logged_in: bool
) -> EventID | None:
    try:
        group = await evt.bridge.signal.get_group(
            evt.sender.username, portal.chat_id, portal.revision
        )
    except Exception:
        evt.log.exception("Failed to get_group(%s) for manual bridging.", portal.chat_id)
        if is_logged_in:
            return await evt.reply(
                "Failed to get info of signal chat. You are logged in, are you in that chat?"
            )
        else:
            return await evt.reply(
                "Failed to get info of signal chat. "
                "You're not logged in, this should not happen."
            )

    portal.mxid = room_id
    portal.by_mxid[portal.mxid] = portal
    (
        portal.title,
        portal.about,
        levels,
        portal.encrypted,
        portal.photo_id,
        join_rule,
    ) = await get_initial_state(evt.az.intent, evt.room_id)
    await portal.save()
    await portal.update_bridge_info()

    background_task.create(portal.update_matrix_room(evt.sender, group))

    await warn_missing_power(levels, evt)

    return await evt.reply("Bridging complete. Portal synchronization should begin momentarily.")


async def warn_missing_power(levels: PowerLevelStateEventContent, evt: CommandEvent) -> None:
    bot_pl = levels.get_user_level(evt.az.bot_mxid)
    if bot_pl < levels.get_event_level(EventType.ROOM_POWER_LEVELS):
        await evt.reply(missing_power_warning.format(bot_mxid=evt.az.bot_mxid))
    elif bot_pl <= 50:
        await evt.reply(low_power_warning.format(bot_mxid=evt.az.bot_mxid))
    if levels.state_default < 50 and (
        levels.events[EventType.ROOM_NAME] >= 50
        or levels.events[EventType.ROOM_AVATAR] >= 50
        or levels.events[EventType.ROOM_TOPIC] >= 50
    ):
        await evt.reply(meta_power_warning)


@command_handler(
    needs_auth=False,
    management_only=False,
    help_section=SECTION_SIGNAL,
    help_text="Invite a Signal user by phone number",
    help_args="<_phone_>",
)
async def invite(evt: CommandEvent) -> EventID | None:
    if not evt.is_portal:
        return await evt.reply("This is not a portal room.")
    portal = evt.portal
    puppet = await _get_puppet_from_cmd(evt)
    if not puppet:
        return None
    levels = await portal.main_intent.get_power_levels(portal.mxid)
    if levels.get_user_level(puppet.mxid) < levels.invite:
        return await evt.reply("You do not have permissions to invite users to this room")

    try:
        info = await portal.handle_matrix_invite(evt.sender, puppet)
        sender, is_relay = await portal.get_relay_sender(evt.sender, "updating info")
        await portal.update_info(sender, info)
    except RejectMatrixInvite as e:
        return await evt.reply(f"Failed to invite {puppet.name}: {e}")