Added file downloading, updated to v0.5.1

- `RoomEventData` is renamed to `EventContext` and moved to context.py
- `EventContext.filter` is removed
- Added context variables system which improves type hints and simplifies callbacks code
- `BodyCommandFilter` sets context variables from now on
- Added `super().__call__` invocation to filters implements in base.py
- Examples are updated to include required changes

.gitignore

@@ -1,4 +1,5 @@
 __pycache__/
+session_storage/
 *.vscode
 .venv/
 dist/

README.md

@@ -1,69 +1,122 @@
-# mab
+# 🤖 mab
 
 **mab** *(MAtrix Bot)* is a **very** simple Python package that can be used to
-develop **very** simple Matrix bots. I have decided to make something like this
-because I wasn't satisfied by simplicity and usage of other libraries. So
-this library does not aim to be "the best matrix bot library", it only aims to
-be good enough for me.
+develop **very** simple Matrix bots. It does not aim to be the best library out
+there, but it aims to be convenient and usable for relatively serious projects.
 
-## Features
+## ✨ Features
 
-The package supports the following features:
+The library supports the following features:
+- **Completely `asyncio` based**
 - **Filter-based callback system**
-- **Images sending**
-- **Videos sending with automatic thumbnail generation (requires `ffmpeg`)**
+- **Downloading and transparently decrypting files**
+- **Sending images**
+- **Sending videos with automatic thumbnail generation (requires `ffmpeg`)**
 
-## Installation
+## 📦 Installation
 
-Use `pip` to install this package:
+Use `apt` to install required system packages and `pip` to install the package.
+You may need to use `root` privileges to use `apt`. It's highly recommended you
+use `venv` or another Python virtual environment. Here are the commands to
+install the latest version of the library:
 
 ```bash
-python -m pip install git+https://git.tyukalov.su/nikita/mab@v0.3.0
+apt install libmagic1-dev libolm-dev
+python -m pip install git+https://git.tyukalov.su/nikita/mab@v0.5.1
 ```
 
-You should specify package version you want to use, because `main` without tags
-contain unstable code.
+`libmagic1-dev` is needed for automatic file MIME type detection, `libolm-dev`
+is needed for E2EE to work.
 
-## Basic usage
+Please inspect [`examples/image_gen_bot.py`](examples/image_gen_bot.py),
+[`examples/echo_bot.py`](examples/echo_bot.py) or open [`examples/`](examples/)
+directory to find usage examples. Examples require that you set
+`MATRIX_HOMESERVER` and `MATRIX_USERNAME` environment variables. Examples create
+`session_storage` directory in working directory.
 
-This is the most simple bot you can create. It would respond to any message
-that starts with `!test`, `!hello` or `!hi`.
+## 🚀 Usage
 
-```python
-import asyncio
-from mab import MatrixBot, MatrixBotConfig
-from mab import TextCommandFilter
-from mab.types import RoomEventData
+If you use `mab`, your application will *most likely* be using **callbacks** to
+react to user actions. `mab` uses filter-based callback system to avoid exposing
+raw `nio-matrix` event objects.
 
-async def on_valid_command(data: RoomEventData) -> None:
-    # do not respond to ourselves
-    if event.sender == data.bot.get_client().user_id:
-        return
-    text = f"Your message contains {len(data.event.body)} symbols"
-    await data.bot.send_text_to_room(data.room, text)
+This is the workflow you will most likely follow:
+1. **Define the callback as `async` function that take 1 argument of type
+   `EventContext`.** For example, this callback would print the caption of the
+   message:
+   ```python
+   from mab import *
 
-async def main() -> None:
-    # create and start the bot
-    cfg = MatrixBotConfig(
-        matrix_homeserver_url="matrix.domain.su",
-        matrix_username_localpart="nagibator666",
-        storage_directory=Path("storage_nagibator666")
-    )
-    bot = MatrixBot(matrix_bot_config)
-    bot.add_callback(
-        TextCommandFilter(["test", "hello", "hi"]),
-        on_valid_command
-    )
-    await bot.start()
-    # wait for Ctrl+C
-    try:
-        while True:
-            await asyncio.sleep(1)
-    except:
-        pass
-    # stop the bot
-    await bot.stop()
+   async def on_media_with_body(ctx: EventContext):
+       """To be called when a message with image/video and caption is received."""
+       print(ctx[CTX_BODY])
+   ```
+2. **Define the conditions your callback must be called on.** For example, you
+   may want your callback to be called when `the sender is not the bot` and
+   `the message contains textual body` and (`the message is an image` or
+   `the message is a video`).
+3. **Define the conditions as `filters`.** Most of them are pretty
+   straightforward. For example, if you want to use the conditions from above:
+   ```python
+   from mab import *
 
-if __name__ == "__main__":
-    asyncio.run(main())
+   filters = (
+       ~SenderIsBotFilter()
+       & MessageTypeFilter([MessageType.IMAGE, MessageType.VIDEO])
+       & BodyExistsFilter()
+   )
+   ```
+4. **Add the callback to your `MatrixBot` instance.** For example, if you would
+   have used everything from above, then your code would look something like
+   this:
+   ```python
+   from mab import *
+
+   # let's assume you create your MatrixBot as `bot` variable here
+
+   async def on_media_with_body(ctx: EventContext):
+       """To be called when a message with image/video and caption is received."""
+       print(ctx[CTX_BODY])
+   
+   filters = (
+       ~SenderIsBotFilter()
+       & MessageTypeFilter([MessageType.IMAGE, MessageType.VIDEO])
+       & BodyExistsFilter()
+   )
+   bot.add_callback(filters, on_media_with_body)
+
+   ...
+   ```
+
+Filters support bitwise operators to implement complex matching logic. Some
+filters set context variables which can be accessed by
+`context[CTX_KEY_NAME]`-like syntax. Possible variables are defined in
+[this file](src/mab/context.py). Filters are implemented in
+[files of this directory](src/mab/filters/).
+
+## 🏷️ Versioning
+
+Releases are tagged in this repository using the `vX.Y.Z` format. If the commit
+is not tagged, it must be treated as versionless and should not be used for your
+application.
+- `X` **(Major)**: Breaking architectiral changes or complete rewrites. Existing
+  code will break. Note that `0.Y.Z` versions are considered **very unstable**,
+  the API may change at any time and some features do not work as expected.
+- `Y` **(Minor)**: Breaking API changes, feature removals, or behavioral
+  modifications. Existing code will likely break.
+- `Z` **(Patch)**: Backward-compatible feature additions, bug fixes, or internal
+  changes. Existing code will not break.
+
+## 🛠️ Development
+
+Here's the list of commands you should execute to get started with development
+(including cloning the repository and installing required packages). Please note
+that your workflow may use something other than `venv`.
+```bash
+apt install libmagic1-dev libolm-dev
+git clone https://git.tyukalov.su/nikita/mab
+cd mab
+python3 -m venv .venv
+. .venv/bin/activate
+pip install -e .
 ```

examples/_environment.py

@@ -0,0 +1,18 @@
+import os
+import sys
+
+def check_environment() -> None:
+    """
+    This function checks if required environment variables are set. It prints
+    problem resolution guide and exits using `sys.exit(1)` on problem.
+    """
+    if "MATRIX_HOMESERVER" not in os.environ:
+        print("Please set `MATRIX_HOMESERVER` environment variable!")
+        print("P.S. use something like this in your shell:")
+        print("    export MATRIX_HOMESERVER=\"https://matrix.server.net\"")
+        sys.exit(1)
+    if "MATRIX_USERNAME" not in os.environ:
+        print("Please set `MATRIX_USERNAME` environment variable!")
+        print("P.S. use something like this in your shell:")
+        print("    export MATRIX_USERNAME=\"megakiller228\"")
+        sys.exit(1)

examples/command_bot.py

@@ -0,0 +1,130 @@
+"""
+This example implements Matrix bot that can execute some commands.
+
+It uses environment variables to specify authorization data. Use Ctrl+C to stop
+the bot.
+"""
+
+import asyncio
+import time
+import html
+import os
+import traceback
+import logging
+
+from mab import *
+
+from _environment import check_environment
+
+async def on_help_command(ctx: EventContext) -> None:
+    """!help"""
+    HELP_MESSAGE = (
+        "<strong>Here is the list of the commands:</strong><br>"
+        "<ul>"
+        "<li><code>!help</code> - this help message</li>"
+        "<li><code>!time</code> - get UNIX timestamp</li>"
+        "<li><code>!raise</code> - raise <code>RuntimeError()</code></li>"
+        "<li><code>!assert</code> - perform <code>assert</code> that will fail</li>"
+        "<li><code>!mul A B [C] [D]...</code> - multiply A, B... and so on</li>"
+        "<li><code>!args arg1 [arg2] ... [arg5]</code> - command that takes 1..5 arguments</li>"
+        "</ul>"
+    )
+    await ctx.bot.send_text(ctx.room, HELP_MESSAGE)
+
+async def on_time_command(ctx: EventContext) -> None:
+    """!time"""
+    await ctx.bot.send_text(
+        ctx.room,
+        f"Current UNIX timestamp is <strong>{int(time.time())}</strong>"
+    )
+
+async def on_raise_command(ctx: EventContext) -> None:
+    """!raise"""
+    await ctx.bot.send_text(
+        ctx.room,
+        "<strong>Executing <code>raise RuntimeError()</code>...</strong>"
+    )
+    raise RuntimeError()
+
+async def on_assert_command(ctx: EventContext) -> None:
+    """!assert"""
+    await ctx.bot.send_text(
+        ctx.room,
+        "<strong>Executing <code>assert False</code>...</strong>"
+    )
+    assert False
+
+async def on_mul_command(ctx: EventContext) -> None:
+    """!mul"""
+    try:
+        numbers = [float(v) for v in ctx[CTX_CMD_ARGS]]
+        v = numbers[0]
+        for n in numbers[1:]:
+            v *= n
+        response = " * ".join(html.escape("%.2f" % n) for n in numbers)
+        response += f" = <strong>{html.escape(str(v))}<strong>"
+        await ctx.bot.send_text(ctx.room, response)
+    except Exception as e:
+        await ctx.bot.send_text(ctx.room, f"Could not process the command: {e}")
+
+async def on_args_command(ctx: EventContext) -> None:
+    """!args"""
+    try:
+        response = (
+            f"Prefix: <code>{ctx[CTX_CMD_PREFIX]}</code><br>"
+            f"Verb: <code>{ctx[CTX_CMD_VERB]}</code><br>"
+            f"Arguments: <code>{len(ctx[CTX_CMD_ARGS])}</code><br>"
+            f"Arguments are:<br><ol>"
+        )
+        for arg in ctx[CTX_CMD_ARGS]:
+            response += f"<li><code>{html.escape(arg)}</code></li>"
+        response += "</ol>"
+        await ctx.bot.send_text(
+            ctx.room,
+            response
+        )
+    except:
+        await ctx.bot.send_text(
+            ctx.room,
+            f"Could not process the command: {traceback.format_exc()}"
+        )
+
+async def invalid_usage(ctx: EventContext) -> None:
+    """This callback is called when the bot used incorrectly."""
+    await ctx.bot.send_text(ctx.room, "Use <code>!help</code>")
+
+
+async def main() -> None:
+    """Application entry point"""
+    logging.basicConfig(level=logging.INFO)
+    logging.getLogger("nio").setLevel(logging.CRITICAL+1)
+    check_environment()
+
+    config = MatrixBotConfig(
+        matrix_homeserver_url=os.environ["MATRIX_HOMESERVER"],
+        matrix_username_localpart=os.environ["MATRIX_USERNAME"],
+        storage_directory="session_storage"
+    )
+    bot = MatrixBot(config)
+
+    COMMANDS = {
+        on_help_command: BodyCommandFilter(["help", "?"]),
+        on_time_command: BodyCommandFilter("time"),
+        on_raise_command: BodyCommandFilter("raise"),
+        on_assert_command: BodyCommandFilter("assert"),
+        on_mul_command: BodyCommandFilter("mul", min_args=2),
+        on_args_command: BodyCommandFilter("args", min_args=1, max_args=5),
+    }
+    for callback, filter in COMMANDS.items():
+        f = ~SenderIsBotFilter() & filter
+        bot.add_callback(f, callback)
+    bot.add_callback(~SenderIsBotFilter() & NewMessageFilter(), invalid_usage)
+
+    # run until Ctrl+C
+    try:
+        await bot.run()
+    except asyncio.CancelledError:
+        pass
+
+if __name__ == "__main__":
+    asyncio.run(main())

examples/echo_bot.py

@@ -0,0 +1,43 @@
+"""
+This example implements Matrix bot that echoes all text messages it receives.
+
+It uses environment variables to specify authorization data. Use Ctrl+C to stop
+the bot.
+"""
+
+import asyncio
+import os
+import logging
+
+from mab import *
+
+from _environment import check_environment
+
+async def on_text_message(ctx: EventContext) -> None:
+    """This callback is called when a text message arrives."""
+    await ctx.bot.send_text(ctx.room, ctx[CTX_BODY])
+
+async def main() -> None:
+    """Application entry point"""
+    logging.basicConfig(level=logging.INFO)
+    logging.getLogger("nio").setLevel(logging.CRITICAL+1)
+    check_environment()
+
+    config = MatrixBotConfig(
+        matrix_homeserver_url=os.environ["MATRIX_HOMESERVER"],
+        matrix_username_localpart=os.environ["MATRIX_USERNAME"],
+        storage_directory="session_storage"
+    )
+    bot = MatrixBot(config)
+    bot.add_callback(
+        ~SenderIsBotFilter() & BodyExistsFilter() & MessageTypeFilter(MessageType.TEXT),
+        on_text_message)
+
+    # run until Ctrl+C
+    try:
+        await bot.run()
+    except asyncio.CancelledError:
+        pass
+
+if __name__ == "__main__":
+    asyncio.run(main())

examples/image_bot.py

@@ -0,0 +1,132 @@
+"""
+This example implements Matrix bot that generates a pixelized noise image with
+specified maximum R, G and B values.
+
+It uses environment variables to specify authorization data. Use Ctrl+C to stop
+the bot.
+"""
+
+import asyncio
+from io import BytesIO
+import os
+import time
+import logging
+import random
+from PIL import Image, ImageFilter
+
+from mab import *
+
+from _environment import check_environment
+
+async def on_gen_command(data: EventContext) -> None:
+    """This callback is called when `!gen R G B` command is received."""
+    # convert R, G and B to floats
+    try:
+        r, g, b = [float(v) for v in data[CTX_CMD_ARGS]]
+    except:
+        await data.bot.send_text(data.room, "Invalid arguments")
+        return
+    await data.bot.send_text(data.room, "Generating the noise...")
+    # create the basic noise
+    img = Image.new("RGB", (16, 16))
+    for x in range(img.width):
+        for y in range(img.height):
+            col = (random.random() * r, random.random() * g, random.random() * b)
+            img.putpixel(
+                (x, y),
+                tuple(int(c * 255) for c in col)
+            )
+    # pixelized upscale
+    img = img.resize((2048, 2048), resample=Image.Resampling.NEAREST)
+    # save to buffer
+    buf = BytesIO()
+    img.save(buf, format="PNG")
+    buf.seek(0)
+    buf = buf.read()
+    # send
+    await data.bot.send_image_bytes(data.room, buf, "noise.png")
+
+async def on_image(ctx: EventContext) -> None:
+    """This callback is called when an image is received."""
+    # download
+    s = time.time()
+    data = await ctx.bot.download_file(ctx)
+    took_time = time.time() - s
+    if not isinstance(data, bytes):
+        await ctx.bot.send_text(ctx.room, "😧")
+        return
+    # convert to Image
+    with BytesIO(data) as buf:
+        img = Image.open(buf)
+        # apply effects
+        blur = ImageFilter.GaussianBlur(
+            radius=min(img.size[0] // 10, 5)
+        )
+        img = img.filter(blur)
+    # save to buffer
+    buf = BytesIO()
+    img.save(buf, format="PNG")
+    buf.seek(0)
+    buf = buf.read()
+    # send
+    await ctx.bot.send_image_bytes(
+        ctx.room,
+        buf,
+        "blurred.png",
+        text="Download and decryption took %.4f seconds" % took_time
+    )
+
+async def on_wrong_message(data: EventContext) -> None:
+    """This callback is called when a wrong message is received."""
+    await data.bot.send_text(
+        data.room,
+        "Text me something like <code>!gen 0.1 0.7 1.0</code> or send an image to blur"
+    )
+
+async def main() -> None:
+    """Application entry point"""
+    logging.basicConfig(level=logging.INFO)
+    logging.getLogger("nio").setLevel(logging.CRITICAL+1)
+    check_environment()
+
+    config = MatrixBotConfig(
+        matrix_homeserver_url=os.environ["MATRIX_HOMESERVER"],
+        matrix_username_localpart=os.environ["MATRIX_USERNAME"],
+        storage_directory="session_storage"
+    )
+    bot = MatrixBot(config)
+    command_filter = MessageTypeFilter(MessageType.TEXT) & BodyCommandFilter(
+        verbs=["gen"],
+        min_args=3,
+        max_args=3
+    )
+
+    # callback for message that
+    # 1. are sent not by this bot
+    # 2. do match the command filter
+    bot.add_callback(
+        ~SenderIsBotFilter() & command_filter,
+        on_gen_command)
+
+    # callback for new image message
+    bot.add_callback(
+        ~SenderIsBotFilter() & MessageTypeFilter(MessageType.IMAGE) & NewMessageFilter(),
+        on_image
+    )
+    
+    # callback for message that
+    # 1. are sent not by this bot
+    # 2. are new messages (not edits)
+    bot.add_callback(
+        ~SenderIsBotFilter() & BodyExistsFilter() & NewMessageFilter(),
+        on_wrong_message
+    )
+
+    # run until Ctrl+C
+    try:
+        await bot.run()
+    except asyncio.CancelledError:
+        pass
+
+if __name__ == "__main__":
+    asyncio.run(main())

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "mab"
-version = "0.3.0"
+version = "0.5.1"
 authors = [
     { name = "Tyukalov Nikita", email = "nikita@tyukalov.su" }
 ]

src/mab/__init__.py

@@ -1,12 +1,14 @@
 from . import bot
 from . import types
 
-from .types import MatrixBotConfig
+from .types import MatrixBotConfig, MessageType
+from .context import *
 
 from .bot import MatrixBot
 
 from .filters.base import *
-from .filters.text import *
+from .filters.message import *
+from .filters.body import *
 
 __all__ = [
     # module names
@@ -15,18 +17,37 @@ __all__ = [
 
     # .types
     "MatrixBotConfig",
+    "MessageType",
+
+    # .context
+    "EventContext",
+    "CTX_BODY",
+    "CTX_MESSAGE_TYPE",
+    "CTX_SENDER",
+    "CTX_CMD_PREFIX",
+    "CTX_CMD_VERB",
+    "CTX_CMD_ARGS",
 
     # .bot
     "MatrixBot",
 
     # .filters.base
     "BaseEventFilter",
+    "EventTypeFilter",
 
-    # .filters.text
-    "TextFilter",
-    "FormattedTextFilter",
-    "TextContainsFilter",
-    "TextStartsWithFilter",
-    "TextEndsWithFilter",
-    "TextCommandFilter",
+    # .filters.body
+    "BodyExistsFilter",
+    "BodyContainsFilter",
+    "BodyStartsWithFilter",
+    "BodyEndsWithFilter",
+    "BodyCommandFilter",
+    "BodyRegexFilter",
+
+    # .filters.message
+    "MessageTypeFilter",
+    "NewMessageFilter",
+    "EditedMessageFilter",
+    "RedactedMessageFilter",
+    "SenderIsFilter",
+    "SenderIsBotFilter",
 ]

src/mab/bot/_callbacks.py

@@ -10,7 +10,8 @@ from nio import MatrixInvitedRoom, InviteMemberEvent, JoinResponse
 from nio.events.room_events import Event as RoomEvent
 
 from ._storage import Storage
-from ..types import MatrixBotConfig, RoomEventData
+from ..types import MatrixBotConfig
+from ..context import EventContext
 from ..filters.base import BaseEventFilter
 
 if TYPE_CHECKING:
@@ -31,7 +32,7 @@ class Callbacks:
         filter: BaseEventFilter
         """Filter to use for matching"""
 
-        callback: Callable[[RoomEventData], Coroutine[Any, Any, None]] | None
+        callback: Callable[[EventContext], Coroutine[Any, Any, None]] | None
         """Callback that will be called if the filter matches"""
 
         stop_matching: bool
@@ -51,14 +52,19 @@ class Callbacks:
         for callback_info in self._filters:
             if not isinstance(callback_info, self._FilterBasedCallback):
                 continue
-            if not await callback_info.filter(room, event, self._client):
-                continue
-            event_data = RoomEventData(
+            event_data = EventContext(
                 room=room,
                 event=event,
-                filter=callback_info.filter,
                 bot=self._matrix_bot
             )
+            try:
+                if not await callback_info.filter(event_data):
+                    continue
+            except asyncio.CancelledError:
+                raise
+            except:
+                self._logger.error(traceback.format_exc())
+                continue
             try:
                 # dump argument types
                 if callback_info.callback is None:
@@ -138,7 +144,7 @@ class Callbacks:
     def add_room_event_callback(
             self,
             filter: BaseEventFilter,
-            callback: Callable[[RoomEventData], Coroutine[Any, Any, None]] | None,
+            callback: Callable[[EventContext], Coroutine[Any, Any, None]] | None,
             *,
             stop_matching: bool = True) -> None:
         """

src/mab/bot/_client_downloader.py

@@ -0,0 +1,241 @@
+import asyncio
+import aiofiles
+import logging
+import os
+import time
+import threading
+import traceback
+import random
+from pathlib import Path
+
+import hashlib
+import hmac
+import unpaddedbase64
+from Crypto.Cipher import AES
+from Crypto.Util import Counter
+
+from nio import (
+    AsyncClient,
+    Event,
+    DiskDownloadResponse,
+    MemoryDownloadResponse
+)
+
+from ..types import MatrixBotConfig
+from ..context import EventContext
+
+class ClientDownloader:
+    """This class downloads files"""
+
+    def __init__(self):
+        self._logger = logging.getLogger("ClientSender")
+        self._config: MatrixBotConfig | None = None
+        self._client: AsyncClient | None = None
+
+    async def setup(self,
+                    config: MatrixBotConfig,
+                    client: AsyncClient) -> None:
+        """
+        Setup the sender.
+
+        Args:
+            - config - config to use
+            - client - client to use
+        """
+        self._config = config
+        self._client = client
+
+    async def _decrypt_file(self,
+                            src: Path,
+                            dst: Path,
+                            key: str,
+                            iv: str,
+                            sha256: str) -> None:
+        """
+        Decrypts `src` and saves it as `dst` asynchronously.
+        
+        Args:
+            - src - path to the source (encrypted) file
+            - dst - path where the resulting (decrypted) file will be saved
+            - key - key, from event["content"]["file"]["key"]["k"]
+            - iv - initialization vector, from event["content"]["file"]["iv"]
+            - sha256 - SHA-256 digest, from
+                       event["content"]["file"]["hashes"]["sha256"]
+        
+        Returns:
+            - Returns nothing on success
+            - Raises an exception on error
+        """
+        async with aiofiles.open(src, "rb") as reader:
+            # check file hash
+            expected = unpaddedbase64.decode_base64(sha256)
+            digest = hashlib.sha256()
+            while chunk := await reader.read(16 * 1024):
+                digest.update(chunk)
+            if not hmac.compare_digest(digest.digest(), expected):
+                raise RuntimeError("SHA256 mismatch")
+            await reader.seek(0)
+            # decrypt
+            decoded_key = unpaddedbase64.decode_base64(key)
+            decoded_iv = unpaddedbase64.decode_base64(iv)
+            cipher = AES.new(
+                decoded_key,
+                AES.MODE_CTR,
+                counter=Counter.new(
+                    nbits=64,
+                    prefix=decoded_iv[:8],
+                    initial_value=int.from_bytes(decoded_iv[8:], "big")
+                )
+            )
+            async with aiofiles.open(dst, "wb") as writer:
+                while chunk := await reader.read(16 * 1024):
+                    await writer.write(cipher.decrypt(chunk))
+
+    async def _decrypt_bytes(self,
+                             data: bytes,
+                             key: str,
+                             iv: str,
+                             sha256: str) -> bytes:
+        """
+        Decrypts `data`. It starts subthread that performs decryption.
+        
+        Args:
+            - data - data that needs to be decrypted
+            - key - key, from event["content"]["file"]["key"]["k"]
+            - iv - initialization vector, from event["content"]["file"]["iv"]
+            - sha265 - SHA-256 digest, from
+                       event["content"]["file"]["hashes"]["sha256"]
+        
+        Returns:
+            - Returns decrypted data on success
+            - Raises an exception on error
+        """
+        cancel = threading.Event()
+        # subfunction that will run in another thread
+        def decrypt() -> bytes:
+            chunk_size = 64 * 1024
+            view = memoryview(data)
+            expected = unpaddedbase64.decode_base64(sha256)
+            digest = hashlib.sha256()
+            for offset in range(0, len(view), chunk_size):
+                if cancel.is_set():
+                    return b""
+                digest.update(view[offset:offset + chunk_size])
+            if not hmac.compare_digest(digest.digest(), expected):
+                raise RuntimeError("SHA-256 mismatch")
+            # prepare AES-CTR
+            decoded_key = unpaddedbase64.decode_base64(key)
+            decoded_iv = unpaddedbase64.decode_base64(iv)
+            cipher = AES.new(
+                decoded_key,
+                AES.MODE_CTR,
+                counter=Counter.new(
+                    nbits=64,
+                    prefix=decoded_iv[:8],
+                    initial_value=int.from_bytes(decoded_iv[8:], "big"),
+                ),
+            )
+            # decrypt
+            result = bytearray()
+            for offset in range(0, len(view), chunk_size):
+                if cancel.is_set():
+                    return b""
+                result.extend(
+                    cipher.decrypt(view[offset:offset + chunk_size])
+                )
+            return bytes(result)
+        # decrypt in thread
+        try:
+            return await asyncio.to_thread(decrypt)
+        except asyncio.CancelledError:
+            cancel.set()
+            raise
+
+    async def download_file(self,
+                            source: EventContext | Event,
+                            *,
+                            path: str | Path | None = None) -> Path | bytes:
+        """
+        Download the file from the event. Automatically deciphers encrypted
+        media.
+
+        Args:
+            - source - event that has a file in its `content`
+            - path - where to save the file to. Use `None` to store the file in
+                     memory. Use path to specify file download path.
+        
+        Returns:
+            - Returns `Path` to the file on success (if `path` isn't `None`)
+            - Returns `bytes` of the file on success (if `path` is `None`)
+            - Raises an exception on error
+        """
+        if self._client is None:
+            raise RuntimeError("ClientDownloader is not set up")
+        # prepare the args
+        if isinstance(source, EventContext):
+            source = source.event
+        content: dict = source.source["content"]
+        f = content.get("file")
+        # encypted
+        if f:
+            if not isinstance(f["url"], str):
+                raise RuntimeError("`source` does not contain file URL")
+            mxc = f["url"]
+            if f["key"]["alg"].upper() != "A256CTR":
+                raise NotImplementedError(
+                    f"Unsupported encryption algorithm `{f['key']['alg']}`"
+                )
+            key: str | None = f["key"]["k"]
+            iv: str | None = f["iv"]
+            sha256: str | None = f["hashes"]["sha256"]
+        # not encrypted
+        else:
+            mxc = content["url"]
+            key = None
+            iv = None
+            sha256 = None
+        # prepare path
+        if isinstance(path, str):
+            path = Path(path)
+        filename: str | None = \
+            os.path.basename(path) if isinstance(path, Path) else None
+        # download
+        result = await self._client.download(
+            mxc,
+            filename=filename,
+            save_to=path
+        )
+        # check the response
+        if isinstance(result, DiskDownloadResponse):
+            result = Path(result.body)
+        elif isinstance(result, MemoryDownloadResponse):
+            result = result.body
+        else:
+            raise RuntimeError(result)
+        # decrypt if needed
+        temp_path: Path | None = None
+        try:
+            if key is not None and iv is not None and sha256 is not None:
+                # on disk
+                if isinstance(result, Path):
+                    r = unpaddedbase64.encode_base64(random.randbytes(8))
+                    temp_path = result.with_name(
+                        f".{result.name}.{int(time.time())}{r}.tmp"
+                    )
+                    await self._decrypt_file(
+                        result, temp_path, key, iv, sha256
+                    )
+                    result.unlink()
+                    temp_path.replace(result)
+                    temp_path = None
+                # in memory
+                else:
+                    result = await self._decrypt_bytes(
+                        result, key, iv, sha256
+                    )
+        finally:
+            if isinstance(temp_path, Path) and isinstance(result, Path):
+                result.unlink(missing_ok=True)
+                temp_path.unlink(missing_ok=True)
+        # return the result
+        return result

src/mab/bot/_client_manager.py

@@ -191,11 +191,13 @@ class ClientManager:
                 raise RuntimeError("The bot was never started")
         self._background_task.cancel()
         try:
-            asyncio.shield(self._background_task)
+            await asyncio.shield(self._background_task)
+        except asyncio.CancelledError:
+            pass
         except:
             self._logger.error(traceback.format_exc())
         try:
-            asyncio.shield(self._close_client())
+            await asyncio.shield(self._close_client())
         except:
             self._logger.error(traceback.format_exc())
         self._background_task = None

src/mab/bot/_client_sender.py

@@ -1,4 +1,5 @@
 import asyncio
+from io import BytesIO
 import logging
 from html.parser import HTMLParser
 from pathlib import Path
@@ -214,6 +215,69 @@ class ClientSender:
         }
         return (await self.send_content(room, content)).event_id
 
+    async def send_image_bytes(self,
+                               room: MatrixRoom | str,
+                               data: bytes,
+                               filename: str,
+                               *,
+                               text: str | None = None,
+                               is_html: bool | None = None,
+                               timeout: float | None = 60 * 60) -> str:
+        """
+        Send the image to `room`. Please note that formatted text is displayed
+        incorrectly in some clients as of September 8th, 2026
+
+        Args:
+            - room - the room to send the text to
+            - bytes - the image to send
+            - filename - filename to use for the file
+            - text - image caption to use (`None` to disable)
+            - is_html - whether the text is HTML-formatted (`None` for auto)
+            - timeout - upload timeout in seconds (`None` to disable)
+        
+        Returns:
+            - `event_id` of sent message on success
+            - Raises an exception on error
+        """
+        # caption must not actually be empty
+        if text is None or not text.strip():
+            text = filename
+            is_html = False
+        # check if the file is image
+        mime_type: str = magic.from_buffer(data, mime=True)
+        if not mime_type.startswith("image/"):
+            raise RuntimeError(f"Data has non-image mime-type")
+        # get image size
+        buffer = BytesIO(data)
+        with Image.open(buffer) as image:
+            width, height = image.size
+        buffer.seek(0)
+        # upload
+        async with asyncio.timeout(timeout):
+            upload_result = await self._uploader.upload_using_provider(
+                provider=buffer,
+                mime_type=mime_type,
+                filename=filename,
+                filesize=len(data))
+        # prepare the content and send
+        content = {
+            "msgtype": "m.image",
+            "filename": filename,
+            **self._process_html_text(text, is_html),
+            "file": {
+                "url": upload_result.response.content_uri,
+                "mimetype": mime_type,
+                **upload_result.keys
+            },
+            "info": {
+                "mimetype": mime_type,
+                "size": upload_result.filesize,
+                "w": width,
+                "h": height
+            }
+        }
+        return (await self.send_content(room, content)).event_id
+
     async def send_video(self,
                          room: MatrixRoom | str,
                          path: Path | str,

src/mab/bot/bot.py

@@ -1,15 +1,18 @@
+import asyncio
 import logging
 
 from typing import Callable, Coroutine, Any
 
-from nio import AsyncClient
+from nio import AsyncClient, MatrixRoom, Event
 
 from ..filters.base import BaseEventFilter
 from ..types import *
+from ..context import EventContext
 
 from ._validation import Validator
 from ._storage import Storage
 from ._client_auth import ClientAuth
+from ._client_downloader import ClientDownloader
 from ._client_manager import ClientManager
 from ._client_uploader import ClientUploader
 from ._client_sender import ClientSender
@@ -31,6 +34,7 @@ class MatrixBot:
         self._client_auth = ClientAuth(self._storage)
         self._client_manager = ClientManager(self._client_auth, self._storage)
         self._client_uploader = ClientUploader(self._storage)
+        self._client_downloader = ClientDownloader()
         self._client_sender = ClientSender()
         self._callbacks = Callbacks(self._storage, self)
         # validate the config and save it
@@ -43,7 +47,7 @@ class MatrixBot:
 
     def add_callback(self,
                            filter: BaseEventFilter,
-                           callback: Callable[[RoomEventData], Coroutine[Any, Any, None]] | None,
+                           callback: Callable[[EventContext], Coroutine[Any, Any, None]] | None,
                            *,
                            stop_matching: bool = True) -> None:
         """
@@ -78,6 +82,10 @@ class MatrixBot:
             self._config,
             self._client_manager.get_client()
         )
+        await self._client_downloader.setup(
+            self._config,
+            self._client_manager.get_client()
+        )
         await self._client_sender.setup(
             self._config,
             self._client_manager.get_client(),
@@ -97,6 +105,20 @@ class MatrixBot:
         """
         await self._client_manager.stop()
 
+    async def run(self) -> None:
+        """
+        Start bot operation in foreground. You may cancel task running this
+        method to stop the bot.
+
+        Warning: calling `stop()` is not a supported way to stop the bot. You
+        should cancel this task instead.
+        """
+        await self.start()
+        try:
+            await asyncio.Event().wait()
+        finally:
+            await self.stop()
+
     def get_client(self) -> AsyncClient:
         """
         Get AsyncClient.
@@ -162,6 +184,39 @@ class MatrixBot:
             timeout=timeout
         )
 
+    async def send_image_bytes(self,
+                               room: MatrixRoom | str,
+                               data: bytes,
+                               filename: str,
+                               *,
+                               text: str | None = None,
+                               is_html: bool | None = None,
+                               timeout: float | None = 60 * 60) -> str:
+        """
+        Send the image to `room`. Please note that formatted text is displayed
+        incorrectly in some clients as of September 8th, 2026
+
+        Args:
+            - room - the room to send the text to
+            - bytes - the image to send
+            - filename - filename to use for the file
+            - text - image caption to use (`None` to disable)
+            - is_html - whether the text is HTML-formatted (`None` for auto)
+            - timeout - upload timeout in seconds (`None` to disable)
+        
+        Returns:
+            - `event_id` of sent message on success
+            - Raises an exception on error
+        """
+        return await self._client_sender.send_image_bytes(
+            room=room,
+            data=data,
+            filename=filename,
+            text=text,
+            is_html=is_html,
+            timeout=timeout
+        )
+
     async def send_video(self,
                          room: MatrixRoom | str,
                          path: Path | str,
@@ -196,3 +251,26 @@ class MatrixBot:
             is_html=is_html,
             timeout=timeout
         )
+    
+    async def download_file(self,
+                            source: EventContext | Event,
+                            *,
+                            path: str | Path | None = None) -> Path | bytes:
+        """
+        Download the file from the event. Automatically dechiphers encrypted
+        media.
+
+        Args:
+            - source - event that has a file in its `content`
+            - path - where to save the file to. Use `None` to store the file in
+                     memory. Use path to specify file download path.
+        
+        Returns:
+            - Returns `Path` to the file on success (if `path` isn't `None`)
+            - Returns `bytes` of the file on success (if `path` is `None`)
+            - Raises an exception on error
+        """
+        return await self._client_downloader.download_file(
+            source=source,
+            path=path
+        )

src/mab/context.py

@@ -0,0 +1,79 @@
+"""This module implements logic for event context"""
+
+from dataclasses import dataclass
+from typing import Any, TYPE_CHECKING
+
+from .types import ContextDataKey, MessageType
+
+from nio import MatrixRoom, Event
+
+if TYPE_CHECKING:
+    from .bot import MatrixBot
+
+#
+# Possible context variables
+#
+CTX_BODY = ContextDataKey[str]("CTX_BODY")
+"""Value of `event.body`"""
+
+CTX_MESSAGE_TYPE = ContextDataKey[MessageType]("CTX_MESSAGE_TYPE")
+"""Value of `msgtype` for the event"""
+
+CTX_SENDER = ContextDataKey[str]("CTX_SENDER")
+"""Value of `event.sender`"""
+
+CTX_CMD_PREFIX = ContextDataKey[str]("CTX_CMD_PREFIX")
+"""Command prefix that was used when matching"""
+
+CTX_CMD_VERB = ContextDataKey[str]("CTX_CMD_VERB")
+"""The verb that was used to execute the command"""
+
+CTX_CMD_ARGS = ContextDataKey[list[str]]("CTX_CMD_ARGS")
+"""Arguments that were passed with the command"""
+
+CTX_ROOM_ENCRYPTED = ContextDataKey[bool]("CTX_ROOM_ENCRYPTED")
+"""True if the room is encrypted"""
+
+
+#
+# EventContext implementation
+#
+@dataclass
+class EventContext:
+    """The class holding information about an event that happened in the room"""
+
+    room: MatrixRoom
+    """The room the event has happened in"""
+
+    event: Event
+    """The event that has happened in the room"""
+
+    bot: "MatrixBot"
+    """The bot that is the source of the event"""
+
+    def __setitem__[T](self, key: ContextDataKey[T], value: T | None) -> None:
+        """Set a value inside the context data storage. `None` removes it"""
+        if not hasattr(self, "_datastore"):
+            self._datastore: dict[ContextDataKey, Any] = {}
+        if value is None:
+            del self._datastore[key]
+        else:
+            self._datastore[key] = value
+
+    def __getitem__[T](self, key: ContextDataKey[T]) -> T:
+        """
+        Get a value inside the context data storage.
+        
+        Raises RuntimeError if the value is not present.
+        """
+        if not hasattr(self, "_datastore") or key not in self._datastore:
+            raise RuntimeError(f"Context does not contain {repr(key)}")
+        return self._datastore[key]
+
+    def __contains__[T](self, key: ContextDataKey[T]) -> bool:
+        """Check if context data storage contains the value"""
+        if not hasattr(self, "_datastore"):
+            return False
+        if key not in self._datastore:
+            return False
+        return True

src/mab/filters/base.py

@@ -1,13 +1,20 @@
 from abc import ABC, abstractmethod
 import logging
+from typing import Any, Type
 
 from nio import AsyncClient
 from nio import MatrixRoom, Event
 
+from ..context import EventContext
+
 class BaseEventFilter(ABC):
     """Base class for all message filters"""
     _logger = logging.Logger("EventFilter")
 
+    def __init__(self, **kwargs):
+        for a in kwargs:
+            self._logger.critical(f"Unknown keyword argument for some filter is used: '{a}'={repr(kwargs[a])}")
+
     # AND
     def __and__(self, other):
         if not isinstance(other, BaseEventFilter):
@@ -30,7 +37,7 @@ class BaseEventFilter(ABC):
         )
 
     def __ror__(self, other):
-        return self.__ror__(other)
+        return self.__or__(other)
 
     # XOR
     def __xor__(self, other):
@@ -52,30 +59,41 @@ class BaseEventFilter(ABC):
         )
 
     # PAYLOAD
-    @abstractmethod
     def __repr__(self) -> str:
-        """This method must be redefined in derived classes to improve
-           debugging experience.
         """
-        pass
-
-    @abstractmethod
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        """This abstract method must be redefined in derived classes so that
-           the filter operates according to its description. This method must
-           not raise exceptions. In case of exception it should log it using
-           `self._logger` and return False
-           
-            Args:
-                room - room the event has happened in
-                event - the event to check againts this filter
-                client - the client
-            
-            Returns:
-                True if the event satisfies this filter
-                False if the event does not satisfy this filter
+        This method may be redefined in derived classes to improve debugging
+        experience.
         """
-        pass
+        return str(self.__class__.__name__)
+
+    async def __call__(self, context: EventContext) -> bool:
+        """
+        This abstract method must be redefined in derived classes so that the
+        filter operates according to its description. This method must not raise
+        exceptions. In case of exception it should log it using `self._logger`
+        and return False
+        
+        Args:
+            - context - event context; your derived classes may add variables
+                        to it (see `message.MessageTypeFilter` implementation
+                        for reference)
+        
+        Returns:
+            - True if the event satisfies this filter
+            - False if the event does not satisfy this filter
+        """
+        return True
+
+class EventTypeFilter(BaseEventFilter):
+    """Event filter that checks if the event is an instance of some class"""
+    def __init__(self, type: Type, **kwargs):
+        super().__init__(**kwargs)
+        self._type = type
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        return isinstance(context.event, self._type)
 
 class CompoundEventFilter(BaseEventFilter):
     """Event filter that consists of multiple filters"""
@@ -104,8 +122,8 @@ class CompoundEventFilter(BaseEventFilter):
             CompoundEventFilter.OPERATOR_INVERT: [1],
         }[op]
 
-    def __init__(self, operator: str, arguments: list[BaseEventFilter]):
-        super().__init__()
+    def __init__(self, operator: str, arguments: list[BaseEventFilter], **kwargs):
+        super().__init__(**kwargs)
         if not self._is_operator_valid(operator):
             raise RuntimeError(f"Invalid operator `{operator}`")
         if not self._is_elements_count_valid(operator, len(arguments)):
@@ -126,8 +144,10 @@ class CompoundEventFilter(BaseEventFilter):
             expression = f"~{reprs[0]}"
         return f"({expression})"
 
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        evaluated = [await arg(room, event, client) for arg in self._arguments]
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        evaluated = [await arg(context) for arg in self._arguments]
         if self._operator == self.OPERATOR_AND:
             return all(evaluated)
         elif self._operator == self.OPERATOR_OR:

src/mab/filters/body.py

@@ -1,11 +1,18 @@
 import re
 import traceback
-from .base import BaseEventFilter
+from .message import NewMessageFilter
+from ..context import EventContext
+from ..context import (
+    CTX_BODY,
+    CTX_CMD_PREFIX,
+    CTX_CMD_VERB,
+    CTX_CMD_ARGS
+)
 
 from nio import AsyncClient
 from nio import MatrixRoom, Event
 
-class TextFilter(BaseEventFilter):
+class BodyExistsFilter(NewMessageFilter):
     """
     This filter returns True if all conditions are met:
     1. `event` has attribute `body`
@@ -14,48 +21,37 @@ class TextFilter(BaseEventFilter):
 
     If this filter matches, you can access `event.body` and it stores
     unformatted text of the message.
+
+    If `event.body` value equals to `event.source["content"]["filename"]` (if it
+    is present, of course) then this filter will not match it by default. You
+    may disable `ignore_filename_in_body` to disable this feature.
+
+    This filter will match any message that has `body` in it, including images,
+    videos, files, etc.
+
+    This filter sets `CTX_BODY` context variable.
     """
-    def __init__(self):
-        super().__init__()
+    def __init__(self, *, ignore_filename_in_body: bool = True, **kwargs):
+        super().__init__(**kwargs)
+        self._ignore_filename_in_body = ignore_filename_in_body
 
-    def __repr__(self) -> str:
-        return "TextFilter()"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not hasattr(event, "body"):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
-        if not isinstance(event.body, str): # type: ignore
+        if not hasattr(context.event, "body"):
             return False
-        if not event.body.strip(): # type: ignore
+        if not isinstance(context.event.body, str): # type: ignore
             return False
+        if not context.event.body.strip(): # type: ignore
+            return False
+        if self._ignore_filename_in_body:
+            content = context.event.source["content"]
+            if "filename" in content and content["filename"] == context.event.body: # type: ignore
+                return False
+        context[CTX_BODY] = context.event.body # type: ignore
         return True
 
-class FormattedTextFilter(BaseEventFilter):
-    """
-    This filter returns True if all conditions are met:
-    1. `event` has attribute `formatted_body`
-    2. `event.formatted_body` is instance of `str`
-    3. `event.formatted_body.strip()` evaluates to True
-
-    If this filter matches, you can access `event.formatted_body` and it stores
-    formatted text of the message.
-    """
-    def __init__(self):
-        super().__init__()
-
-    def __repr__(self):
-        return "FormattedTextFilter()"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not hasattr(event, "formatted_body"):
-            return False
-        if not isinstance(event.formatted_body, str): # type: ignore
-            return False
-        if not event.formatted_body.strip(): # type: ignore
-            return False
-        return True
-
-class TextContainsFilter(TextFilter):
+class BodyContainsFilter(BodyExistsFilter):
     """
     This filter returns True if `event.body` contains `needle` substring (or any
     of neddle from the list). `event.body` will be converted to lower case if
@@ -68,26 +64,23 @@ class TextContainsFilter(TextFilter):
     is True. That means you must ensure that `needle` is lower case. The filter
     will never match otherwise.
     """
-    def __init__(self, needle: str | list[str], *, any_case: bool = True):
-        super().__init__()
+    def __init__(self, needle: str | list[str], *, any_case: bool = True, **kwargs):
+        super().__init__(**kwargs)
         if type(needle) is str:
             needle = [needle]
         self._any_case = any_case
         self._needle = needle
 
-    def __repr__(self) -> str:
-        return f"TextContainsFilter({repr(self._needle)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not await super().__call__(room, event, client):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
-        body = event.body.lower() if self._any_case else event.body # type: ignore
+        body = context.event.body.lower() if self._any_case else context.event.body # type: ignore
         for n in self._needle:
             if n in body:
                 return True
         return False
 
-class TextStartsWithFilter(TextFilter):
+class BodyStartsWithFilter(BodyExistsFilter):
     """
     This filter returns True if `event.body` starts with `substring` (or any of
     substrings from the list). The check will be case insensetive if `any_case`
@@ -100,26 +93,23 @@ class TextStartsWithFilter(TextFilter):
     is True. That means you must ensure that `needle` is lower case. The filter
     will never match otherwise.
     """
-    def __init__(self, substring: str | list[str], *, any_case: bool = True):
-        super().__init__()
+    def __init__(self, substring: str | list[str], *, any_case: bool = True, **kwargs):
+        super().__init__(**kwargs)
         if type(substring) is str:
             substring = [substring]
         self._any_case = any_case
         self._substring = substring
 
-    def __repr__(self):
-        return f"TextStartsWithFilter({repr(self._substring)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not await super().__call__(room, event, client):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
-        body = event.body.lower() if self._any_case else event.body # type: ignore
+        body = context.event.body.lower() if self._any_case else context.event.body # type: ignore
         for s in self._substring:
             if body.startswith(s):
                 return True
         return False
         
-class TextEndsWithFilter(TextFilter):
+class BodyEndsWithFilter(BodyExistsFilter):
     """
     This filter returns True if `event.body` ends with `substring` (or any of
     substrings from the list). The check will be case insensetive if `any_case`
@@ -132,26 +122,23 @@ class TextEndsWithFilter(TextFilter):
     is True. That means you must ensure that `needle` is lower case. The filter
     will never match otherwise.
     """
-    def __init__(self, substring: str | list[str], *, any_case: bool = True):
-        super().__init__()
+    def __init__(self, substring: str | list[str], *, any_case: bool = True, **kwargs):
+        super().__init__(**kwargs)
         if type(substring) is str:
             substring = [substring]
         self._any_case = any_case
         self._substring = substring
 
-    def __repr__(self):
-        return f"TextEndsWithFilter({repr(self._substring)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not await super().__call__(room, event, client):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
-        body = event.body.lower() if self._any_case else event.body # type: ignore
+        body = context.event.body.lower() if self._any_case else context.event.body # type: ignore
         for s in self._substring:
             if body.endswith(s):
                 return True
         return False
 
-class TextCommandFilter(TextFilter):
+class BodyCommandFilter(BodyExistsFilter):
     """
     This filter returns True if all conditions are met:
     1. `event.body` contains at least `min_args + 1` words after split()
@@ -168,12 +155,13 @@ class TextCommandFilter(TextFilter):
     store all verbs in lower case. This filter will not match any verbs that
     use mixed case of upper case.
 
-    If this filter is matched, then it will set a new attribute for the event:
-    `event.command_args: list[str]`. You may use this attribute in your callback
-    for this event.
+    This filter sets the following context variables:
+    - `CTX_CMD_PREFIX` - prefix that was used
+    - `CTX_CMD_VERB` - verb that was used
+    - `CTX_CMD_ARGS` - arguments that were passed
     """
-    def __init__(self, verbs: str | list[str], min_args: int = 0, max_args: int | None = None, prefix: str = "!"):
-        super().__init__()
+    def __init__(self, verbs: str | list[str], min_args: int = 0, max_args: int | None = None, prefix: str = "!", **kwargs):
+        super().__init__(**kwargs)
         if type(verbs) is str:
             verbs = [verbs]
         self._verbs = verbs
@@ -181,13 +169,10 @@ class TextCommandFilter(TextFilter):
         self._max_args = max_args
         self._prefix = prefix
 
-    def __repr__(self):
-        return f"TextCommandFilter({repr(self._verbs)}, {repr(self._min_args)}, {repr(self._max_args)}, {repr(self._prefix)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not await super().__call__(room, event, client):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
-        parts = [p.strip() for p in event.body.split() if p.strip()] # type: ignore
+        parts = [p.strip() for p in context.event.body.split() if p.strip()] # type: ignore
         args_count = len(parts) - 1
         if args_count < self._min_args:
             return False
@@ -198,27 +183,27 @@ class TextCommandFilter(TextFilter):
         cmd = parts[0][len(self._prefix):].lower()
         for verb in self._verbs:
             if cmd == verb:
-                setattr(event, "command_args", parts[1:])
+                context[CTX_CMD_PREFIX] = self._prefix
+                context[CTX_CMD_VERB] = verb
+                context[CTX_CMD_ARGS] = parts[1:]
                 return True
         return False
 
-class TextRegexFilter(TextFilter):
+class BodyRegexFilter(BodyExistsFilter):
     """
     This filter returns True if the `event.body` passes the regex.
     """
-    def __init__(self, regex: re.Pattern | str):
+    def __init__(self, regex: re.Pattern | str, **kwargs):
+        super().__init__(**kwargs)
         if isinstance(regex, str):
             regex = re.compile(regex)
         self._regex = regex
 
-    def __repr__(self):
-        return f"TextRegexFilter({repr(self._regex)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        if not await super().__call__(room, event, client):
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
             return False
         try:
-            return self._regex.match(event.body) # type: ignore
+            return self._regex.match(context.event.body) is not None # type: ignore
         except:
             self._logger.error(traceback.format_exc())
             return False

src/mab/filters/message.py

@@ -0,0 +1,121 @@
+import traceback
+from .base import BaseEventFilter, EventTypeFilter
+from ..types import MessageType
+from ..context import EventContext, CTX_MESSAGE_TYPE, CTX_SENDER
+
+from nio import AsyncClient
+from nio import MatrixRoom, Event
+
+from nio import RedactionEvent
+
+class MessageTypeFilter(BaseEventFilter):
+    """
+    This filter should be used to match specific message types (text-only,
+    images, videos, files, etc) based on `event.source["content"]["msgtype"]`
+    value.
+
+    `types` list is stored by reference so you may modify the behavior of this
+    filter dynamically.
+
+    This filter sets `CTX_MESSAGE_TYPE` variable in the context.
+    """
+    def __init__(self, types: list[MessageType] | MessageType, **kwargs):
+        super().__init__(**kwargs)
+        if isinstance(types, MessageType):
+            types = [types]
+        self._types = types
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        if "msgtype" not in context.event.source["content"]:
+            return False
+        msgtype = context.event.source["content"]["msgtype"]
+        if not msgtype in [t.value for t in self._types]:
+            return False
+        context[CTX_MESSAGE_TYPE] = MessageType(msgtype)
+        return True
+
+class NewMessageFilter(BaseEventFilter):
+    """
+    This filter returns True if the event is a new message. Most filters are
+    derived from this base class because it ignores events about edited
+    messages.
+    """
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        return "m.new_content" not in context.event.source["content"]
+
+class EditedMessageFilter(BaseEventFilter):
+    """
+    This filter returns True if the event is an edited message. You may use this
+    filter to create callbacks that are called if the message gets edited.
+    """
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        return "m.new_content" in context.event.source["content"]
+
+class RedactedMessageFilter(EventTypeFilter):
+    """
+    This filter returns True if the event is a RedactionEvent.
+    """
+    def __init__(self, **kwargs):
+        super().__init__(RedactionEvent, **kwargs)
+        raise NotImplementedError()
+
+    async def __call__(self, context: EventContext) -> bool:
+        raise NotImplementedError()
+
+class SenderIsFilter(BaseEventFilter):
+    """
+    This filter returns True if `event.sender` is any of specified senders.
+    `event.sender` is converted to lower case if `any_case` is True (default).
+    Supplied sender list is NEVER converted to lower case, so it is your duty to
+    use lower case if `any_case` is True.
+
+    `senders` list is stored by reference so you can modify behavior of this
+    filter dynamically.
+
+    This filter sets `CTX_SENDER` variable in the context.
+    """
+    def __init__(self, sender: list[str] | str, *, any_case: bool = True, **kwargs):
+        super().__init__(**kwargs)
+        if isinstance(sender, str):
+            sender = [sender]
+        self._sender = sender
+        self._any_case = any_case
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        sender = context.event.sender.lower() if self._any_case else context.event.sender
+        for s in self._sender:
+            if sender == s:
+                context[CTX_SENDER] = sender
+                return True
+        return False
+
+class SenderIsBotFilter(BaseEventFilter):
+    """
+    This filter returns True if `event.sender` is the client that has received
+    the event. You may use this filter to set callbacks for messages sent by
+    other users by using the following syntax:
+    ```py
+    ~SenderIsBotFilter()
+    ```
+    """
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
+        return context.bot.get_client().user_id == context.event.sender

src/mab/filters/room.py

@@ -1,94 +1,6 @@
 from .base import BaseEventFilter
 
-from nio import AsyncClient
-from nio import MatrixRoom, Event
-
-class RoomIdContainsFilter(BaseEventFilter):
-    """
-        This filter returns True if the `room.room_id` contains `needle` (or
-        any of needles from the list). The check will be case insensetive if
-        `any_case` is True.
-    """
-    def __init__(self, needle: str | list[str], *, any_case: bool = True):
-        super().__init__()
-        if type(needle) is str:
-            needle = [needle]
-        self._any_case = any_case
-        if self._any_case:
-            self._needle = [s.lower() for s in needle]
-        else:
-            self._needle = list(needle)
-
-    def __repr__(self):
-        return f"RoomIdContainsFilter({repr(self._needle)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        try:
-            room_id = room.room_id.lower() if self._any_case else room.room_id
-            for s in self._needle:
-                if s in room_id:
-                    return True
-            return False
-        except:
-            return False
-
-class RoomIdStartsWithFilter(BaseEventFilter):
-    """
-        This filter returns True if the `room.room_id` starts with `substring`
-        (or any of substrings from the list). The check will be case insensetive
-        if `any_case` is True.
-    """
-    def __init__(self, substring: str | list[str], *, any_case: bool = True):
-        super().__init__()
-        if type(substring) is str:
-            substring = [substring]
-        self._any_case = any_case
-        if self._any_case:
-            self._substring = [s.lower() for s in substring]
-        else:
-            self._substring = list(substring)
-
-    def __repr__(self):
-        return f"RoomIdStartsWithFilter({repr(self._substring)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        try:
-            room_id = room.room_id.lower() if self._any_case else room.room_id
-            for s in self._substring:
-                if room_id.startswith(s):
-                    return True
-            return False
-        except:
-            return False
-
-class RoomIdEndsWithFilter(BaseEventFilter):
-    """
-        This filter returns True if the `room.room_id` ends with `substring` (or
-        any of substrings from the list). The check will be case insensetive
-        if `any_case` is True.
-    """
-    def __init__(self, substring: str | list[str], *, any_case: bool = True):
-        super().__init__()
-        if type(substring) is str:
-            substring = [substring]
-        self._any_case = any_case
-        if self._any_case:
-            self._substring = [s.lower() for s in substring]
-        else:
-            self._substring = list(substring)
-
-    def __repr__(self):
-        return f"RoomIdEndsWithFilter({repr(self._substring)}, any_case={repr(self._any_case)})"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
-        try:
-            room_id = room.room_id.lower() if self._any_case else room.room_id
-            for s in self._substring:
-                if room_id.endswith(s):
-                    return True
-            return False
-        except:
-            return False
+from ..context import EventContext, CTX_ROOM_ENCRYPTED
 
 class RoomEncryptedFilter(BaseEventFilter):
     """
@@ -97,11 +9,11 @@ class RoomEncryptedFilter(BaseEventFilter):
     def __init__(self):
         super().__init__()
 
-    def __repr__(self):
-        return f"RoomEncryptedFilter()"
-
-    async def __call__(self, room: MatrixRoom, event: Event, client: AsyncClient) -> bool:
+    async def __call__(self, context: EventContext) -> bool:
+        if not await super().__call__(context):
+            return False
         try:
-            return room.encrypted
+            context[CTX_ROOM_ENCRYPTED] = context.room.encrypted
+            return context.room.encrypted
         except:
             return False

src/mab/types.py

@@ -2,16 +2,10 @@
 
 from pathlib import Path
 from dataclasses import dataclass
+from enum import Enum
 
-from nio import MatrixRoom, Event
 from nio import UploadResponse
 
-from .filters.base import BaseEventFilter
-
-from typing import TYPE_CHECKING
-if TYPE_CHECKING:
-    from .bot import MatrixBot
-
 @dataclass
 class MatrixBotConfig:
     """Configuration for MatrixBot"""
@@ -67,22 +61,6 @@ class VideoFileProperties:
     thumbnail: Path | str | bytes | None = None
     """Path to the thumbnail or the raw JPEG thumbnail data"""
 
-@dataclass
-class RoomEventData:
-    """Dataclass that hold information about event that happened in the room"""
-
-    room: MatrixRoom
-    """The room the event has happened in"""
-
-    event: Event
-    """The event that has happened in the room"""
-
-    filter: BaseEventFilter
-    """The filter that invoked this event"""
-
-    bot: "MatrixBot"
-    """The bot that is the source of the event"""
-
 @dataclass
 class UploadResult:
     """Result of data upload"""
@@ -98,3 +76,30 @@ class UploadResult:
 
     filesize: int
     """Size of uploaded file"""
+
+class MessageType(Enum):
+    TEXT = "m.text"
+    EMOTE = "m.emote"
+    NOTICE = "m.notice"
+    IMAGE = "m.image"
+    FILE = "m.file"
+    AUDIO = "m.audio"
+    LOCATION = "m.location"
+    VIDEO = "m.video"
+
+class ContextDataKey[T]:
+    """
+    Instances of this class represent a single possible data key that can be
+    stored inside EventContext.
+    """
+    def __init__(self, name: str) -> None:
+        """
+        Initialize a ContextDataKey
+        
+        Args:
+            - name - name that will be used internally
+        """
+        self._name = name
+
+    def __repr__(self) -> str:
+        return f"ContextDataKey[{type(T)}]({repr(self._name)})"