"""Auto-inibizione dei layer ML quando il modello non è reperibile.

Regola: un layer ML è disponibile solo se ENABLE_ML è attivo **e** il suo modello
è reperibile (cache HF, MODELS_DIR, o online). Altrimenti `available()` è False →
il provider non lo costruisce e la UI lo segnala (vedi layer_catalog).

`zero_shot` è un caso speciale: ha GLiNER **con fallback NLI**, quindi è
disponibile se è reperibile almeno uno dei due modelli.
"""

from __future__ import annotations

from config.runtime.settings import Settings
from layers.embedding import main as embedding_main
from layers.ner import main as ner_main
from layers.ner_comuni import main as ner_comuni_main
from layers.zero_shot import main as zero_shot_main

ML_ON = Settings(enable_ml=True)
ML_OFF = Settings(enable_ml=False)


def test_ml_layer_unavailable_when_ml_disabled():
    # ENABLE_ML=False → ogni layer ML è inibito, modello o no.
    assert ner_main.PLUGIN.available(ML_OFF) is False
    assert zero_shot_main.PLUGIN.available(ML_OFF) is False


def test_ner_available_tracks_model(monkeypatch):
    monkeypatch.setattr(ner_main, "model_available", lambda repo: True)
    assert ner_main.PLUGIN.available(ML_ON) is True
    monkeypatch.setattr(ner_main, "model_available", lambda repo: False)
    assert ner_main.PLUGIN.available(ML_ON) is False


def test_ner_comuni_available_tracks_model(monkeypatch):
    monkeypatch.setattr(ner_comuni_main, "model_available", lambda repo: False)
    assert ner_comuni_main.PLUGIN.available(ML_ON) is False


def test_embedding_available_tracks_model(monkeypatch):
    monkeypatch.setattr(embedding_main, "model_available", lambda repo: False)
    assert embedding_main.PLUGIN.available(ML_ON) is False


def test_zero_shot_available_if_gliner_present(monkeypatch):
    # GLiNER reperibile, NLI no → layer disponibile (usa GLiNER).
    def avail(repo):
        return repo == ML_ON.gliner_model

    monkeypatch.setattr(zero_shot_main, "model_available", avail)
    assert zero_shot_main.PLUGIN.available(ML_ON) is True


def test_zero_shot_available_if_only_nli_present(monkeypatch):
    # GLiNER assente ma fallback NLI reperibile → ancora disponibile.
    def avail(repo):
        return repo == ML_ON.zero_shot_model

    monkeypatch.setattr(zero_shot_main, "model_available", avail)
    assert zero_shot_main.PLUGIN.available(ML_ON) is True


def test_zero_shot_unavailable_when_both_models_absent(monkeypatch):
    monkeypatch.setattr(zero_shot_main, "model_available", lambda repo: False)
    assert zero_shot_main.PLUGIN.available(ML_ON) is False


# --- layer_catalog: la UI riceve disponibilità reale + motivo -----------------

def test_layer_catalog_reports_reason_for_missing_model(monkeypatch):
    from web.services.registry import ServiceRegistry

    monkeypatch.setattr(ner_main, "model_available", lambda repo: False)
    reg = ServiceRegistry(Settings(enable_ml=True))
    cat = {layer["key"]: layer for layer in reg.layer_catalog()["layers"]}

    assert cat["ner"]["available"] is False
    assert "models/" in cat["ner"]["unavailable_reason"]
    # 'rules' non è ML: sempre disponibile, nessun motivo.
    assert cat["rules"]["available"] is True
    assert cat["rules"]["unavailable_reason"] is None


def test_layer_catalog_reason_when_ml_disabled():
    from web.services.registry import ServiceRegistry

    reg = ServiceRegistry(Settings(enable_ml=False))
    cat = {layer["key"]: layer for layer in reg.layer_catalog()["layers"]}
    assert cat["ner"]["available"] is False
    assert cat["ner"]["unavailable_reason"] == "richiede ENABLE_ML=true"