"""对抗性测试 — COBOL 匹配分类器的假阳性/假阴性攻击

COBOL 迁移专家设计的攻击面:
- FP: 非匹配程序被误判为マッチング
- FN: 真实匹配程序未被识别
- 边界: 注释关键词、旧式命名、多文件非匹配
"""

from pathlib import Path
import pytest

from cobol_testgen import extract_structure
from hina.pipeline import classify_program
from hina.classifier import detect_keyword

FIXTURES = Path(__file__).parents[3] / "test-data" / "cobol" / "adversarial"

# (filename, expect_matching, reason)
# expect_matching=True → must be マッチング/二段階
# expect_matching=False → must NOT be マッチング/二段階
ADVERSARIAL_TESTS = [
    ("ADV-FALSE-KEY.cbl",    False,
     "FP: WS-KEY 变量但只是简单 ADD 程序，不应触发匹配"),
    ("ADV-KEY-IN-COMMENT.cbl", False,
     "FP: KEY 只在 *> 注释中，不应触发匹配"),
    ("ADV-PREVKEY-FAKE.cbl", False,
     "FP: WS-PREV-KEY 但无匹配逻辑，不应触发匹配"),
    ("ADV-OLD-SCHOOL.cbl",   True,
     "FN: K01-KEY 旧式命名，应识别为匹配"),
    ("ADV-TINY-MATCH.cbl",   True,
     "FN: 极简匹配程序（1 文件），应识别"),
    ("ADV-CALL-MATCH.cbl",   False,
     "FP: CALL+WS-MAST-KEY，子程序调用应优先"),
    ("ADV-ASCII-KEY.cbl",    False,
     "FP: ASCII+WS-KEY，编码转换应优先"),
    ("ADV-10FILES.cbl",      False,
     "FP: 10 文件无 KEY 比较，不应触发匹配"),
]


@pytest.mark.parametrize(
    "filename,expect_matching,reason",
    ADVERSARIAL_TESTS,
    ids=[t[0].replace('.cbl','') for t in ADVERSARIAL_TESTS],
)
def test_adversarial(filename, expect_matching, reason):
    """对抗性测试：验证明假阳性/假阴性"""
    path = FIXTURES / filename
    assert path.exists(), f"Missing: {path}"
    src = path.read_text("utf-8")

    # 1. extract_structure must not crash
    struct = extract_structure(src)
    assert struct is not None

    # 2. classify_program must not crash
    result = classify_program(src)
    assert result is not None
    assert result["confidence"] >= 0

    # 3. False positive/negative check
    is_matching = "マッチング" in result["category"] or "二段階" in result["category"]
    if expect_matching:
        assert is_matching, (
            f"{filename}: expected MATCHING but got '{result['category']}' "
            f"(conf={result['confidence']:.2f}). Reason: {reason}"
        )
    else:
        assert not is_matching, (
            f"{filename}: expected NON-MATCHING but got '{result['category']}' "
            f"(conf={result['confidence']:.2f}). Reason: {reason}"
        )

    # 4. Keyword detection sanity
    kw = detect_keyword(src)
    if expect_matching:
        # Matching programs should have at least 1 keyword match
        assert len(kw) >= 1 or result["method"] != "rule_engine_fallback", (
            f"{filename}: matching program with 0 keyword matches"
        )