"""/api/model/info must bound its context-length probe (#63214).

The resolver chain (``agent.model_metadata.get_model_context_length``) runs
several sequential provider probes, each with its own multi-second timeout, so
an unreachable ``model.base_url`` held the response for tens of seconds — and
the Desktop Model Settings page, which awaits this endpoint inside one
``Promise.all``, showed loading skeletons indefinitely.
"""

from __future__ import annotations

import time


def _config(model: str, provider: str, base_url: str) -> dict:
    return {"model": {"default": model, "provider": provider, "base_url": base_url}}


def test_model_info_degrades_when_the_context_probe_exceeds_its_budget(monkeypatch):
    from hermes_cli.web_routers import models as router

    monkeypatch.setattr(
        router, "_load_config_scoped",
        lambda profile: _config("some-model", "custom-proxy", "http://localhost:9/v1"),
    )
    monkeypatch.setattr(router, "_MODEL_INFO_PROBE_BUDGET_S", 0.2)

    import agent.model_metadata as metadata

    def _hanging_probe(model, base_url="", api_key="", config_context_length=None, provider="", custom_providers=None):
        time.sleep(1.0)
        raise AssertionError("the abandoned probe should never be awaited")

    monkeypatch.setattr(metadata, "get_model_context_length", _hanging_probe)

    started = time.monotonic()
    info = router.get_model_info()
    elapsed = time.monotonic() - started

    # The response degrades to "auto context unknown" instead of hanging…
    assert info["model"] == "some-model"
    assert info["provider"] == "custom-proxy"
    assert info["auto_context_length"] == 0
    # …and it returns within the (shrunk) budget, not the probe's 1s sleep.
    assert elapsed < 0.9


def test_model_info_surfaces_the_context_value_when_the_probe_is_fast(monkeypatch):
    from hermes_cli.web_routers import models as router

    monkeypatch.setattr(
        router, "_load_config_scoped",
        lambda profile: _config("some-model", "custom-proxy", "http://localhost:9/v1"),
    )

    import agent.model_metadata as metadata

    def _fast_probe(model, base_url="", api_key="", config_context_length=None, provider="", custom_providers=None):
        return 131072

    monkeypatch.setattr(metadata, "get_model_context_length", _fast_probe)

    info = router.get_model_info()

    assert info["model"] == "some-model"
    assert info["auto_context_length"] == 131072
    assert info["effective_context_length"] == 131072