refactor(python): streamline record_screen functionality

diff --git a/core/emu.py b/core/emu.py
index b6ec27e9..a754bdc6 100755
--- a/core/emu.py
+++ b/core/emu.py
@@ -9,12 +9,12 @@ import subprocess
 import sys
 import tempfile
 from pathlib import Path
-from typing import Optional, TextIO
+from typing import TextIO
 
 import click
 
 import trezorlib.debuglink
-import trezorlib.device
+from trezorlib.cli.debug import record_screen
 from trezorlib._internal.emulator import CoreEmulator
 
 try:
@@ -133,7 +133,7 @@ def _from_env(name: str) -> bool:
 @click.option("-p", "--profile", metavar="NAME", help="Profile name or path")
 @click.option("-P", "--port", metavar="PORT", type=int, default=int(os.environ.get("TREZOR_UDP_PORT", 0)) or None, help="UDP port number")
 @click.option("-q", "--quiet", is_flag=True, help="Silence emulator output")
-@click.option("-r", "--record-dir", help="Directory where to record screen changes")
+@click.option("-r", "--record-dir", help="Directory where to record screen changes", type=click.Path(file_okay=False, dir_okay=True, path_type=Path))
 @click.option("-s", "--slip0014", is_flag=True, help="Initialize device with SLIP-14 seed (all all all...)")
 @click.option("-S", "--script-gdb-file", type=click.Path(exists=True, dir_okay=False), help="Run gdb with an init file")
 @click.option("-V", "--valgrind", is_flag=True, help="Use valgrind instead of debugger (-D)")
@@ -160,7 +160,7 @@ def cli(
     port: int,
     output: TextIO | None,
     quiet: bool,
-    record_dir: Optional[str],
+    record_dir: Path | None,
     slip0014: bool,
     script_gdb_file: str | Path | None,
     valgrind: bool,
@@ -312,10 +312,7 @@ def cli(
         )
 
     if record_dir:
-        assert emulator.client is not None
-        trezorlib.debuglink.record_screen(
-            emulator.client, record_dir, report_func=print
-        )
+        record_screen(emulator.transport, record_dir)
 
     if run_command:
         ret = run_command_with_emulator(emulator, command)
diff --git a/python/src/trezorlib/cli/__init__.py b/python/src/trezorlib/cli/__init__.py
index 6bfd1cc9..890f1c17 100644
--- a/python/src/trezorlib/cli/__init__.py
+++ b/python/src/trezorlib/cli/__init__.py
@@ -24,6 +24,7 @@ import sys
 import typing as t
 from contextlib import contextmanager
 from enum import Enum
+from pathlib import Path
 
 import click
 
@@ -151,11 +152,13 @@ class TrezorConnection:
         script: bool,
         *,
         app_name: str = "trezorctl",
+        record_dir: Path | None = None,
     ) -> None:
         self.path = path
         self.session_id = session_id
         self.passphrase_source = passphrase_source
         self.script = script
+        self.record_dir = record_dir
         self.credentials = credentials.CredentialStore(app_name)
         self.app = AppManifest(app_name=app_name, credentials=self.credentials.list)
         if self.script:
@@ -202,12 +205,24 @@ class TrezorConnection:
         assert self._transport is not None
         return self._transport
 
+    def _record_screen(self, start: bool) -> None:
+        """Helper wrapping `debug.record_screen()` to avoid circular import."""
+        from .debug import record_screen
+
+        if self.record_dir is None:
+            return
+
+        assert self._transport is not None
+        record_screen(self._transport, self.record_dir if start else None)
+
     def open(self) -> None:
         if self._transport is None:
             self._transport = self._get_transport()
             self._transport.open()
+            self._record_screen(True)
 
     def close(self) -> None:
+        self._record_screen(False)
         if self._transport is not None:
             self._transport.close()
         self._transport = None
diff --git a/python/src/trezorlib/cli/debug.py b/python/src/trezorlib/cli/debug.py
index e38fb2c1..d9f93ea3 100644
--- a/python/src/trezorlib/cli/debug.py
+++ b/python/src/trezorlib/cli/debug.py
@@ -14,45 +14,94 @@
 # You should have received a copy of the License along with this library.
 # If not, see <https://www.gnu.org/licenses/lgpl-3.0.html>.
 
-from typing import TYPE_CHECKING, Union
+from __future__ import annotations
+
+import typing as t
+from datetime import datetime
+from pathlib import Path
 
 import click
 
 from ..client import Session
-from ..debuglink import DebugLink, TrezorTestContext
+from ..debuglink import DebugLink
 from ..debuglink import optiga_set_sec_max as debuglink_optiga_set_sec_max
 from ..debuglink import prodtest_t1 as debuglink_prodtest_t1
-from ..debuglink import record_screen
 from ..debuglink import set_log_filter as debuglink_set_log_filter
+from ..transport import Timeout
+from ..transport.udp import UdpTransport
 from . import with_session
 
-if TYPE_CHECKING:
+if t.TYPE_CHECKING:
+    from ..transport import Transport
     from . import TrezorConnection
 
 
+def _get_session_screenshot_dir(base_dir: Path) -> Path:
+    """Create and return screenshot dir for the current session, according to datetime."""
+    timestamp_str = datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
+    session_dir = base_dir / timestamp_str
+    ctr = 1
+    while session_dir.exists() and any(session_dir.iterdir()):
+        session_dir = base_dir / f"{timestamp_str}_{ctr}"
+        ctr += 1
+
+    session_dir.mkdir(parents=True, exist_ok=True)
+    return session_dir
+
+
+def record_screen(transport: Transport, base_dir: Path | None) -> None:
+    """Record screen changes into a specified directory.
+
+    Passing `None` as `directory` stops the recording.
+
+    Creates subdirectories inside a specified directory, one for each session
+    (for each new call of this function).
+    (So that older screenshots are not overwritten by new ones.)
+
+    Is available only for emulators, hardware devices are not capable of that.
+    """
+    if not isinstance(transport, UdpTransport):
+        raise click.ClickException("Recording is only supported on emulator.")
+
+    debug_transport = transport.find_debug()
+    with debug_transport:
+        try:
+            debug_transport.wait_until_ready(timeout=1)
+        except Timeout:
+            raise click.ClickException("Debuglink is not responding.") from None
+
+        debug = DebugLink(transport=debug_transport)
+
+        if base_dir is None:
+            debug.stop_recording()
+            click.echo("Recording stopped.")
+        else:
+            current_session_dir = _get_session_screenshot_dir(base_dir)
+            debug.start_recording(str(current_session_dir.resolve()))
+            click.echo(f"Recording started into {current_session_dir}.")
+
+
 @click.group(name="debug")
 def cli() -> None:
     """Miscellaneous debug features."""
 
 
 @cli.command()
-@click.argument("directory", required=False)
+@click.argument(
+    "directory",
+    required=False,
+    type=click.Path(file_okay=False, dir_okay=True, path_type=Path),
+)
 @click.option("-s", "--stop", is_flag=True, help="Stop the recording")
 @click.pass_obj
-def record(obj: "TrezorConnection", directory: Union[str, None], stop: bool) -> None:
+def record(obj: "TrezorConnection", directory: Path | None, stop: bool) -> None:
     """Record screen changes into a specified directory.
 
     Recording can be stopped with `-s / --stop` option.
     """
-    record_screen_from_connection(obj, None if stop else directory)
-
-
-def record_screen_from_connection(
-    obj: "TrezorConnection", directory: Union[str, None]
-) -> None:
-    """Record screen helper to transform TrezorConnection into TrezorClientDebugLink."""
-    debug_client = TrezorTestContext(transport=obj.transport, auto_interact=False)
-    record_screen(debug_client, directory, report_func=click.echo)
+    if not stop and directory is None:
+        raise click.ClickException("Specify either a directory path or --stop.")
+    record_screen(obj.transport, None if stop else directory)
 
 
 @cli.command()
diff --git a/python/src/trezorlib/cli/trezorctl.py b/python/src/trezorlib/cli/trezorctl.py
index 6c0171da..e121bd16 100755
--- a/python/src/trezorlib/cli/trezorctl.py
+++ b/python/src/trezorlib/cli/trezorctl.py
@@ -24,6 +24,7 @@ import json
 import logging
 import os
 import time
+from pathlib import Path
 from typing import Any, Callable, Optional, TypeVar, cast
 
 import click
@@ -204,6 +205,7 @@ def configure_logging(verbose: int) -> None:
 @click.option(
     "-r",
     "--record",
+    type=click.Path(file_okay=False, dir_okay=True, path_type=Path),
     help="Record screen changes into a specified directory.",
 )
 @click.version_option(package_name="trezor")
@@ -217,7 +219,7 @@ def cli_main(
     passphrase_on_host: bool,
     script: bool,
     session_id: Optional[str],
-    record: Optional[str],
+    record: Path | None,
 ) -> None:
     configure_logging(verbose)
 
@@ -232,14 +234,16 @@ def cli_main(
     else:
         passphrase_source = PassphraseSource.AUTO
 
-    ctx.obj = TrezorConnection(path, session_id, passphrase_source, script)
+    ctx.obj = TrezorConnection(
+        path=path,
+        session_id=session_id,
+        passphrase_source=passphrase_source,
+        script=script,
+        record_dir=record,
+    )
     ctx.obj.open()
     atexit.register(ctx.obj.close)
 
-    # Optionally record the screen into a specified directory.
-    if record:
-        debug.record_screen_from_connection(ctx.obj, record)
-
 
 # Creating a cli function that has the right types for future usage
 cli = cast(TrezorctlGroup, cli_main)
@@ -273,19 +277,6 @@ def print_result(res: Any, is_json: bool, script: bool, **kwargs: Any) -> None:
             click.echo(res)
 
 
-@cli.set_result_callback()
-@click.pass_obj
-def stop_recording_action(obj: TrezorConnection, *args: Any, **kwargs: Any) -> None:
-    """Stop recording screen changes when the recording was started by `cli_main`.
-
-    (When user used the `-r / --record` option of `trezorctl` command.)
-
-    It allows for isolating screen directories only for specific actions/commands.
-    """
-    if kwargs.get("record"):
-        debug.record_screen_from_connection(obj, None)
-
-
 def format_device_name(features: messages.Features) -> str:
     model = features.model or "1"
     if features.bootloader_mode:
diff --git a/python/src/trezorlib/debuglink.py b/python/src/trezorlib/debuglink.py
index 914ef258..9161f1f7 100644
--- a/python/src/trezorlib/debuglink.py
+++ b/python/src/trezorlib/debuglink.py
@@ -25,7 +25,6 @@ import typing as t
 import warnings
 from contextlib import contextmanager
 from copy import deepcopy
-from datetime import datetime
 from enum import Enum, IntEnum, auto
 from itertools import zip_longest
 from pathlib import Path
@@ -1793,56 +1792,6 @@ def prodtest_t1(session: client.Session) -> None:
     )
 
 
-def record_screen(
-    debug_client: "TrezorTestContext",
-    directory: str | None,
-    report_func: t.Callable[[str], None] | None = None,
-) -> None:
-    """Record screen changes into a specified directory.
-
-    Passing `None` as `directory` stops the recording.
-
-    Creates subdirectories inside a specified directory, one for each session
-    (for each new call of this function).
-    (So that older screenshots are not overwritten by new ones.)
-
-    Is available only for emulators, hardware devices are not capable of that.
-    """
-
-    def get_session_screenshot_dir(directory: Path) -> Path:
-        """Create and return screenshot dir for the current session, according to datetime."""
-        session_dir = directory / datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
-        session_dir.mkdir(parents=True, exist_ok=True)
-        return session_dir
-
-    if not _is_emulator(debug_client):
-        raise RuntimeError("Recording is only supported on emulator.")
-
-    if directory is None:
-        with debug_client.debug.transport:
-            debug_client.debug.stop_recording()
-        if report_func is not None:
-            report_func("Recording stopped.")
-    else:
-        # Transforming the directory into an absolute path,
-        # because emulator demands it
-        abs_directory = Path(directory).resolve()
-        # Creating the dir when it does not exist yet
-        if not abs_directory.exists():
-            abs_directory.mkdir(parents=True, exist_ok=True)
-        # Getting a new screenshot dir for the current session
-        current_session_dir = get_session_screenshot_dir(abs_directory)
-        with debug_client.debug.transport:
-            debug_client.debug.start_recording(str(current_session_dir))
-        if report_func is not None:
-            report_func(f"Recording started into {current_session_dir}.")
-
-
-def _is_emulator(debug_client: "TrezorTestContext") -> bool:
-    """Check if we are connected to emulator, in contrast to hardware device."""
-    return debug_client.features.fw_vendor == "EMULATOR"
-
-
 def optiga_set_sec_max(debug: DebugLink) -> None:
     debug._call(messages.DebugLinkOptigaSetSecMax())