# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project

from __future__ import annotations

from vllm_omni.engine.duplex.config import DuplexCapabilities
from vllm_omni.model_executor.models.personaplex.duplex.config import CHUNK_PERIOD_MS


def personaplex_capabilities(*, max_sessions: int = 1) -> DuplexCapabilities:
    """What a PersonaPlex session advertises in ``session.created``.

    PersonaPlex is a pure-lockstep model: audio flows both ways at the codec
    frame rate, the model itself decides when to speak, and there are no
    client commits or external turn signals. Barge-in is native model
    behaviour but destructive output interruption and model-state rewind are
    not validated, so it is not advertised. No text seeding exists, so the
    model cannot serve ``/v1/chat/completions``.
    """
    supports_multi_session = max_sessions > 1
    return DuplexCapabilities(
        supports_model_native_turn_policy=True,
        supports_external_turn_signal=False,
        supports_client_commit=False,
        supports_barge_in=False,
        supports_playback_ack=True,
        supports_input_append=True,
        supports_replace_latest_chunk=False,
        supports_reencode_context=False,
        supports_rollback_to_checkpoint=False,
        supports_turn_commit_only=False,
        supports_model_internal_state=True,
        supports_stage_resumption=True,
        supports_core_resumable_request=True,
        supports_stage_connector_handoff=True,
        supports_independent_io_streams=True,
        supports_realtime_endpoint=True,
        supports_multi_session=supports_multi_session,
        supports_multi_session_same_replica=supports_multi_session,
        supports_session_lease=True,
        supports_session_resume=False,
        session_admission_mode="engine_managed",
        supports_audio_truncate=False,
        supports_chat_completions=False,
        requires_model_runner_kv=True,
        requires_native_stage_role=True,
        adapter_patterns=["scheduler_data_plane"],
        signal_sources=["model_native", "client_event"],
        stage_handoff_transport="scheduler_data_plane",
        chunk_period_ms=CHUNK_PERIOD_MS,
        target_barge_in_latency_ms=None,
    )


__all__ = ["personaplex_capabilities"]