Signal/tests/test_readiness.py

"""
Tests for the readiness verdict engine — the "kill the false green" logic.

Source spec: docs/readiness-model-brief-2026-06-23.md section 4 ("The verdict rule").

Two axes, never conflated into one string:
  required_state: does this plan need this item? (from plan_type + rules)
  input_state:    did the client supply data?   (SUPPLIED | ABSENT)

Per DocItem:
  NOT_REQUIRED + any input        -> satisfied (green-eligible)
  REQUIRED + SUPPLIED + good       -> satisfied
  REQUIRED + SUPPLIED + bad        -> gap
  REQUIRED + ABSENT                -> NOT_EVALUATED, blocks green, never satisfied

A line is "Clear to Ship" ONLY if EVERY required item is satisfied. Green is
earned by positive evidence, never granted by the absence of contradiction.
plan_type unknown -> "Plan Type Needed", structurally cannot be green.
"""

import sys
from pathlib import Path
sys.path.insert(0, str(Path(__file__).parent.parent / "python-backend"))

from datetime import date

from core.readiness import (
    evaluate_readiness,
    RequiredState,
    InputState,
    LineStatus,
)

VISIT = date(2026, 5, 1)


def items_by_type(verdict):
    return {i.doc_type: i for i in verdict.doc_items}


# ---------------------------------------------------------------------------
# The four-rule verdict table (brief section 4)
# ---------------------------------------------------------------------------

def test_not_required_item_is_satisfied_even_when_absent():
    """Medicare FFS does not require PA -> PA is satisfied with no input at all."""
    v = evaluate_readiness("medicare", csv_pa_status=None)
    pa = items_by_type(v)["pa"]
    assert pa.required_state == RequiredState.NOT_REQUIRED
    assert pa.satisfied is True


def test_required_supplied_good_is_satisfied():
    v = evaluate_readiness("medicare", csv_swo_status="On File")
    swo = items_by_type(v)["swo"]
    assert swo.required_state == RequiredState.REQUIRED
    assert swo.input_state == InputState.SUPPLIED
    assert swo.satisfied is True


def test_required_supplied_bad_is_gap():
    v = evaluate_readiness("medicare", csv_swo_status="Expired")
    swo = items_by_type(v)["swo"]
    assert swo.satisfied is False


def test_required_absent_blocks_green():
    """THE false-green killer: a required item with no data is never satisfied."""
    v = evaluate_readiness("medicare", csv_swo_status=None)
    swo = items_by_type(v)["swo"]
    assert swo.required_state == RequiredState.REQUIRED
    assert swo.input_state == InputState.ABSENT
    assert swo.satisfied is False


# ---------------------------------------------------------------------------
# Line status — clear to ship is earned, not defaulted
# ---------------------------------------------------------------------------

def _all_docs_good(**overrides):
    base = dict(
        csv_swo_status="On File",
        csv_visit_date=VISIT,
        csv_pecos_verified="Yes",
        csv_pa_status="Not Required",
        csv_diagnosis_on_file="Yes",
    )
    base.update(overrides)
    return base


def test_clear_to_ship_when_every_required_item_satisfied():
    v = evaluate_readiness("medicare", **_all_docs_good())
    assert v.line_status == LineStatus.CLEAR_TO_SHIP


def test_missing_required_item_is_not_clear_to_ship():
    """Old code greened this (absent column = no gap). New code must not."""
    v = evaluate_readiness("medicare", **_all_docs_good(csv_swo_status=None))
    assert v.line_status != LineStatus.CLEAR_TO_SHIP
    assert v.line_status == LineStatus.ACTION_NEEDED


def test_supplied_bad_required_item_is_at_risk():
    v = evaluate_readiness("medicare_advantage", **_all_docs_good(csv_pa_status="Denied"))
    assert v.line_status == LineStatus.AT_RISK


def test_pending_only_is_on_track():
    """No hard gap, no missing data, but an item still in progress -> On Track."""
    v = evaluate_readiness("medicare", **_all_docs_good(csv_swo_status="Pending"))
    assert v.line_status == LineStatus.ON_TRACK


def test_bad_outranks_absent_in_severity():
    """A denied item (At Risk) outranks a missing item (Action Needed)."""
    v = evaluate_readiness(
        "medicare_advantage",
        **_all_docs_good(csv_pa_status="Denied", csv_diagnosis_on_file=None),
    )
    assert v.line_status == LineStatus.AT_RISK


# ---------------------------------------------------------------------------
# Plan type unknown — never guess, cannot be green
# ---------------------------------------------------------------------------

def test_plan_type_none_is_plan_type_needed():
    v = evaluate_readiness(None, **_all_docs_good())
    assert v.line_status == LineStatus.PLAN_TYPE_NEEDED


def test_plan_type_unknown_string_is_plan_type_needed():
    """An unmapped plan value is treated as unknown, never defaulted/guessed."""
    v = evaluate_readiness("unknown", **_all_docs_good())
    assert v.line_status == LineStatus.PLAN_TYPE_NEEDED


def test_plan_unknown_leaves_pecos_and_pa_not_evaluated():
    v = evaluate_readiness(None, **_all_docs_good())
    items = items_by_type(v)
    assert items["pecos"].required_state == RequiredState.NOT_EVALUATED
    assert items["pa"].required_state == RequiredState.NOT_EVALUATED


def test_plan_unknown_still_grades_universal_items():
    """SWO, visit, diagnosis are universal (LCD L33822) -> still graded when plan unknown."""
    v = evaluate_readiness(None, csv_swo_status="On File")
    swo = items_by_type(v)["swo"]
    assert swo.required_state == RequiredState.REQUIRED
    assert swo.satisfied is True


# ---------------------------------------------------------------------------
# Required-ness comes from payer_rules.json, not duplicated Python sets
# ---------------------------------------------------------------------------

def test_pecos_required_for_medicare():
    v = evaluate_readiness("medicare", csv_pecos_verified=None)
    assert items_by_type(v)["pecos"].required_state == RequiredState.REQUIRED


def test_pecos_not_required_for_medicaid():
    """Medicaid uses state enrollment, not PECOS (deferred) -> PECOS not required."""
    v = evaluate_readiness("medicaid", csv_pecos_verified=None)
    assert items_by_type(v)["pecos"].required_state == RequiredState.NOT_REQUIRED


def test_pa_required_for_medicaid():
    v = evaluate_readiness("medicaid", csv_pa_status=None)
    assert items_by_type(v)["pa"].required_state == RequiredState.REQUIRED


def test_pa_not_required_for_medicare_ffs():
    v = evaluate_readiness("medicare", csv_pa_status=None)
    assert items_by_type(v)["pa"].required_state == RequiredState.NOT_REQUIRED


def test_all_five_items_present():
    v = evaluate_readiness("medicare", **_all_docs_good())
    assert set(items_by_type(v).keys()) == {"swo", "visit", "pecos", "pa", "diagnosis"}


def test_diagnosis_supplied_negative_is_gap():
    v = evaluate_readiness("medicare", **_all_docs_good(csv_diagnosis_on_file="No"))
    dx = items_by_type(v)["diagnosis"]
    assert dx.input_state == InputState.SUPPLIED
    assert dx.satisfied is False


# ---------------------------------------------------------------------------
# Hardening (code-auditor findings H1, H2, M1, M2, M3, M4, L1)
# ---------------------------------------------------------------------------

def test_known_plan_missing_config_does_not_false_green():
    """H1/H2: a known plan absent from payer_rules.json must NOT grade green.

    PECOS/PA cannot be evaluated without their rule config -> NOT_EVALUATED,
    which must block 'Clear to Ship'. Fails safe, never open.
    """
    v = evaluate_readiness(
        "medicaid", rules={"payer_rules": {}},
        **_all_docs_good(csv_pa_status="Denied"),
    )
    assert v.line_status != LineStatus.CLEAR_TO_SHIP
    assert items_by_type(v)["pa"].required_state == RequiredState.NOT_EVALUATED
    assert items_by_type(v)["pecos"].required_state == RequiredState.NOT_EVALUATED


def test_diagnosis_icd10_code_counts_as_on_file():
    """M2: a real ICD-10 code in the diagnosis field is positive evidence, not a gap."""
    v = evaluate_readiness("medicare", **_all_docs_good(csv_diagnosis_on_file="E11.9"))
    assert items_by_type(v)["diagnosis"].satisfied is True


def test_diagnosis_explicit_negative_is_bad():
    v = evaluate_readiness("medicare", **_all_docs_good(csv_diagnosis_on_file="Missing"))
    assert items_by_type(v)["diagnosis"].satisfied is False


def test_pecos_enrolled_synonym_is_good():
    """M3: standard PECOS portal statuses should read as verified."""
    v = evaluate_readiness("medicare", **_all_docs_good(csv_pecos_verified="Enrolled"))
    assert items_by_type(v)["pecos"].satisfied is True


def test_swo_active_synonym_is_good():
    v = evaluate_readiness("medicare", **_all_docs_good(csv_swo_status="Active"))
    assert items_by_type(v)["swo"].satisfied is True


def test_plan_type_case_and_whitespace_normalized():
    """M4: a correctly-mapped plan with stray case/space must still grade."""
    v = evaluate_readiness("  Medicare ", **_all_docs_good())
    assert v.line_status == LineStatus.CLEAR_TO_SHIP


def test_staff_confirmed_visit_carries_value_for_citation():
    """L1: a staff-confirmed visit (no CSV date) still records its date for the citation."""
    v = evaluate_readiness(
        "medicare", confirmed_visit_date=VISIT,
        csv_swo_status="On File", csv_pa_status="Not Required",
        csv_diagnosis_on_file="Yes", csv_pecos_verified="Yes",
    )
    assert items_by_type(v)["visit"].value == VISIT.isoformat()


def test_known_plan_types_match_payer_rules_config():
    """M1 drift guard: the gradeable allow-list must equal the configured plans."""
    import json
    rules_path = (
        Path(__file__).parent.parent
        / "python-backend" / "config" / "payer_rules.json"
    )
    configured = set(json.loads(rules_path.read_text())["payer_rules"].keys()) - {"default"}
    from core.readiness import KNOWN_PLAN_TYPES
    assert set(KNOWN_PLAN_TYPES) == configured