"""Unit tests for `run_recipe_ci.resolve_upgrade_base` — the DYNAMIC upgrade-base decision (phase prevb).

Resolution order: upgrade∉stages / EXPECTED_NA[upgrade] (declared skip) → explicit UPGRADE_BASE_VERSION
override → last-green (warm canonical) → target-branch (`main`) tip → skip (no predecessor). The result
is a `BasePlan(kind, version, ref, reason)`: kind ∈ {"version", "ref", "skip"}; `.runs` is True for
version/ref (the upgrade tier runs). Replaces the old static `recipe_versions[-2]` default.
"""

from __future__ import annotations

import os
import sys
from types import SimpleNamespace

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "runner"))
import run_recipe_ci  # noqa: E402
from harness import canonical, lifecycle  # noqa: E402

ALL = {"install", "upgrade", "backup", "restore", "custom"}
HEAD = "aaaa1111head"
MAIN = "bbbb2222main"


def _meta(expected_na=None, upgrade_base_version=None):
    return SimpleNamespace(EXPECTED_NA=expected_na, UPGRADE_BASE_VERSION=upgrade_base_version)


def _no_canonical(monkeypatch):
    monkeypatch.setattr(canonical, "read_registry", lambda r: None)


def _no_main(monkeypatch):
    monkeypatch.setattr(lifecycle, "recipe_branch_commit", lambda r, b="main": None)


def test_upgrade_not_in_stages_skip(monkeypatch):
    # never consults canonical/main when upgrade isn't requested
    monkeypatch.setattr(
        canonical, "read_registry", lambda r: (_ for _ in ()).throw(AssertionError("not consulted"))
    )
    plan = run_recipe_ci.resolve_upgrade_base(ALL - {"upgrade"}, _meta(), "somerecipe")
    assert plan.kind == "skip" and not plan.runs


def test_expected_na_upgrade_skip_even_with_canonical_and_override(monkeypatch):
    # EXPECTED_NA[upgrade] is the strongest, declared fact — short-circuits before override/canonical.
    monkeypatch.setattr(
        canonical, "read_registry", lambda r: {"version": "9.9.9", "status": "warm"}
    )
    declared = {"upgrade": "no deployable upgrade base (moving tag republished)"}
    plan = run_recipe_ci.resolve_upgrade_base(
        ALL, _meta(expected_na=declared, upgrade_base_version="0.2.0+v0.4"), "bluesky-pds"
    )
    assert plan.kind == "skip" and "EXPECTED_NA" in plan.reason


def test_explicit_override_wins_over_canonical(monkeypatch):
    monkeypatch.setattr(
        canonical, "read_registry", lambda r: {"version": "9.9.9", "status": "warm"}
    )
    monkeypatch.setattr(
        lifecycle,
        "recipe_branch_commit",
        lambda r, b="main": (_ for _ in ()).throw(AssertionError("not consulted")),
    )
    plan = run_recipe_ci.resolve_upgrade_base(
        ALL, _meta(upgrade_base_version="0.7.0+3.3.1"), "discourse"
    )
    assert plan.kind == "version" and plan.version == "0.7.0+3.3.1" and plan.runs


def test_last_green_warm_canonical_is_primary(monkeypatch):
    # no override → last-green (warm canonical version) is the PRIMARY base; main is not consulted.
    monkeypatch.setattr(
        canonical, "read_registry", lambda r: {"version": "0.6.0+3.1.1", "status": "idle"}
    )
    monkeypatch.setattr(
        lifecycle,
        "recipe_branch_commit",
        lambda r, b="main": (_ for _ in ()).throw(AssertionError("not consulted")),
    )
    plan = run_recipe_ci.resolve_upgrade_base(ALL, _meta(), "keycloak", head_ref=HEAD)
    assert plan.kind == "version" and plan.version == "0.6.0+3.1.1" and "last-green" in plan.reason


def test_main_tip_fallback_when_no_last_green(monkeypatch):
    _no_canonical(monkeypatch)
    monkeypatch.setattr(lifecycle, "recipe_branch_commit", lambda r, b="main": MAIN)
    plan = run_recipe_ci.resolve_upgrade_base(ALL, _meta(), "discourse", head_ref=HEAD)
    assert plan.kind == "ref" and plan.ref == MAIN and plan.version is None and plan.runs


def test_head_equals_main_tip_skip(monkeypatch):
    # the PR head IS the main tip (empty PR / LATEST run) → no real predecessor → declared skip.
    _no_canonical(monkeypatch)
    monkeypatch.setattr(lifecycle, "recipe_branch_commit", lambda r, b="main": HEAD)
    plan = run_recipe_ci.resolve_upgrade_base(ALL, _meta(), "discourse", head_ref=HEAD)
    assert plan.kind == "skip" and "main tip" in plan.reason and not plan.runs


def test_no_canonical_no_main_skip(monkeypatch):
    _no_canonical(monkeypatch)
    _no_main(monkeypatch)
    plan = run_recipe_ci.resolve_upgrade_base(ALL, _meta(), "brandnew", head_ref=HEAD)
    assert plan.kind == "skip" and "no predecessor" in plan.reason


def test_expected_na_other_rung_does_not_suppress_upgrade(monkeypatch):
    # an EXPECTED_NA for a DIFFERENT rung (backup_restore) must NOT short-circuit the upgrade base —
    # resolution proceeds to last-green/main-tip (custom-html-tiny shape).
    _no_canonical(monkeypatch)
    monkeypatch.setattr(lifecycle, "recipe_branch_commit", lambda r, b="main": MAIN)
    meta = _meta(expected_na={"backup_restore": "stateless"})
    plan = run_recipe_ci.resolve_upgrade_base(ALL, meta, "custom-html-tiny", head_ref=HEAD)
    assert plan.kind == "ref" and plan.ref == MAIN