messageLogger/src/hooks/deletes.py

"""Keeps messages others delete: the delete updates are dropped (the message
stays in the app's cache and chat) and the ids are remembered as deleted.

Deletions the user makes here go through MessagesController.deleteMessages
(both overloads start `(messages, randoms, encryptedChat, dialogId, ...)`);
those ids are let through when their echo update arrives.

TL_updateDeleteMessages (private chats, basic groups) carries no chat: ids
are per account, so the dialog is looked up in the app's own database on the
storage queue.
"""

from base_plugin import HookResult, HookStrategy, MethodHook

import diag
import peers
import store
from api import ApiError
from config import KEEP_DELETED, REPORT_DELETIONS
from jutil import field, hook_methods, in_background, java_ints

UPDATES = ("TL_updateDeleteMessages", "TL_updateDeleteChannelMessages")


class Deletes:
    def __init__(self, plugin, api, chats, dialog=None):
        self.plugin = plugin
        self.api = api
        self.chats = chats
        self.dialog = dialog  # hooks/delete_dialog.DeleteDialog
        self.handles = []

    def install(self):
        for name in UPDATES:
            self.plugin.add_hook(name)
        deletes = self

        class BeforeDelete(MethodHook):
            def before_hooked_method(self, param):
                try:
                    deletes.on_own_delete(param)
                except Exception as exc:
                    diag.error("deletes.own", exc)

        self.handles += hook_methods(
            self.plugin,
            "org.telegram.messenger.MessagesController",
            "deleteMessages",
            BeforeDelete(),
        )

    def uninstall(self):
        for name in UPDATES:
            try:
                self.plugin.remove_hook(name)
            except Exception:
                pass
        for handle in self.handles:
            try:
                self.plugin.unhook_method(handle)
            except Exception:
                pass
        self.handles = []

    def on_own_delete(self, param):
        args = list(param.args or [])
        if len(args) < 4:
            return
        ids = [i for i in java_ints(args[0]) if i > 0]
        if not ids:
            return
        account = int(field(param.thisObject, "currentAccount") or 0)
        dialog_id = int(args[3] or 0)
        kept = self.dialog.apply_choice(account, dialog_id, ids) if self.dialog else []
        if kept:
            self.chats.refresh_dialog(account, dialog_id, kept)
        ids = [i for i in ids if i not in kept]
        if not ids:
            return
        store.note_own_deletion(account, ids)
        store.forget_deleted(account, dialog_id, ids)

    def on_update(self, name, account, update):
        ids = java_ints(update.messages)
        others = [i for i in ids if not store.is_own_deletion(account, i)]
        if not others:
            return HookResult()
        if name == "TL_updateDeleteChannelMessages":
            self._deleted(account, -int(update.channel_id), others)
        else:
            self._resolve_dialogs(account, others)
        if not self.plugin.get_setting(KEEP_DELETED, True):
            return HookResult()
        diag.log(f"kept {name} {others}")
        if len(others) == len(ids):
            return HookResult(strategy=HookStrategy.CANCEL)
        from java import jint
        from java.util import ArrayList

        own = ArrayList()
        for i in ids:
            if i not in others:
                own.add(jint(i))  # a plain int would be boxed as Long
        update.messages = own
        return HookResult(strategy=HookStrategy.MODIFY, update=update)

    def _deleted(self, account, dialog_id, ids):
        store.mark_deleted(account, dialog_id, ids)
        self.chats.refresh_dialog(account, dialog_id, ids)
        # Check the chat again once the server had the report.
        self.chats.changed(account, dialog_id, 3000)
        if self.plugin.get_setting(REPORT_DELETIONS, True) and self.api.configured:
            in_background(lambda: self._report(account, dialog_id, ids))

    def _report(self, account, dialog_id, ids):
        chat_id = peers.marked_chat_id(account, dialog_id)
        if chat_id is None:
            return
        try:
            self.api.deletions(peers.own_user_id(account), chat_id, ids)
        except ApiError as exc:
            diag.log(f"report {chat_id}: {exc}")

    def _resolve_dialogs(self, account, ids):
        """Dialogs of per-account message ids, from the app's database."""
        from java import dynamic_proxy
        from java.lang import Runnable
        from org.telegram.messenger import MessagesStorage

        storage = MessagesStorage.getInstance(account)
        deletes = self

        class Lookup(dynamic_proxy(Runnable)):
            def run(self):
                try:
                    found = {}
                    query = "SELECT mid, uid FROM messages_v2 WHERE mid IN (%s)" % (
                        ",".join(str(int(i)) for i in ids)
                    )
                    cursor = storage.getDatabase().queryFinalized(query)
                    while cursor.next():
                        uid = int(cursor.longValue(1))
                        if uid < 0 and peers.is_channel_dialog(account, uid):
                            continue  # channel ids are numbered per channel
                        found.setdefault(uid, []).append(int(cursor.intValue(0)))
                    cursor.dispose()
                    for dialog_id, mids in found.items():
                        deletes._deleted(account, dialog_id, mids)
                except Exception as exc:
                    diag.error("deletes.resolve", exc)

        storage.getStorageQueue().postRunnable(Lookup())