from __future__ import annotations

from conftest import fixture_text

from companyatlas.sdk import normalize as N
from companyatlas.sdk.diff import compare
from companyatlas.taxonomy import ChangeKind, change_kind

URL = "https://www.acme-cloud.example/pricing"


def _page(name: str, url: str = URL) -> N.NormalizedPage:
    return N.parse(fixture_text("generic_html", name), url=url)


def test_same_page_twice_is_zero() -> None:
    a = _page("pricing.html")
    d = compare(a.blocks, a.blocks, surface="pricing", before_text=a.text, after_text=a.text)
    assert d.significance == 0.0 and d.is_empty and d.reasons == ["identical"]


def test_footer_year_change_is_noise() -> None:
    html = fixture_text("generic_html", "pricing.html")
    a, b = N.parse(html, url=URL), N.parse(html.replace("© 2025", "© 2026"), url=URL)
    d = compare(a.blocks, b.blocks, surface="pricing", before_text=a.text, after_text=b.text)
    assert d.significance < 0.20
    assert change_kind(d.significance) is ChangeKind.NOISE


def test_nav_only_churn_is_noise() -> None:
    html = fixture_text("generic_html", "pricing.html")
    b = N.parse(html.replace('<a href="/docs">Docs</a>', '<a href="/docs">Docs</a> <a href="/partners">Partners</a>'), url=URL)
    a = N.parse(html, url=URL)
    d = compare(a.blocks, b.blocks, surface="pricing", before_text=a.text, after_text=b.text)
    assert d.significance < 0.20
    assert any("nav/footer" in r for r in d.reasons)


def test_price_change_with_typed_delta_is_major() -> None:
    a, b = _page("pricing.html"), _page("pricing_v2.html")
    delta = {"plans": {"added": [], "removed": [], "price_changed": [{"plan_name": "Starter", "before": 29, "after": 39, "currency": "USD", "billing_period": "month", "pct": 34.5}]}}
    d = compare(a.blocks, b.blocks, surface="pricing", before_text=a.text, after_text=b.text, structured_delta=delta)
    assert d.significance >= 0.65
    assert len(d.modified) == 1 and d.modified[0].kind == "pricing_plan"
    assert any("typed delta plans.price_changed" in r for r in d.reasons)


def test_tiny_text_edit_without_typed_delta_is_noise() -> None:
    html = fixture_text("generic_html", "pricing.html")
    a = N.parse(html, url=URL)
    b = N.parse(html.replace("No credit card required.", "No credit card needed."), url=URL)
    d = compare(a.blocks, b.blocks, surface="pricing", before_text=a.text, after_text=b.text)
    assert d.significance < 0.20


def test_new_job_listings_are_meaningful() -> None:
    a = _page("careers.html", "https://www.acme-cloud.example/careers")
    b = _page("careers_v2.html", "https://www.acme-cloud.example/careers")
    delta = {"jobs": {"added": [{"title": "AI Research Scientist"}, {"title": "Data Platform Engineer"}], "removed": [{"title": "People Operations Lead"}],
                      "open_before": 5, "open_after": 6}}
    d = compare(a.blocks, b.blocks, surface="careers", before_text=a.text, after_text=b.text, structured_delta=delta)
    assert change_kind(d.significance) in (ChangeKind.MEANINGFUL, ChangeKind.MAJOR)
    assert len(d.added) >= 2 and len(d.removed) >= 1


def test_whole_redesign_is_major() -> None:
    a = _page("legal_terms.html", "https://www.acme-cloud.example/")
    b = _page("homepage.html", "https://www.acme-cloud.example/")
    d = compare(a.blocks, b.blocks, surface="homepage", before_text=a.text, after_text=b.text)
    assert change_kind(d.significance) in (ChangeKind.MAJOR, ChangeKind.CRITICAL)
    assert d.text_delta_ratio > 0.5


def test_reordered_blocks_are_moves_not_add_remove() -> None:
    html = fixture_text("generic_html", "legal_terms.html")
    a = N.parse(html, url=URL)
    sec2 = html[html.index("<h2>2. Accounts</h2>"):html.index("<h2>3. Fees")]
    sec3 = html[html.index("<h2>3. Fees"):html.index("<h2>4. Termination")]
    b = N.parse(html.replace(sec2 + sec3, sec3 + sec2), url=URL)
    d = compare(a.blocks, b.blocks, surface="legal_terms", before_text=a.text, after_text=b.text)
    assert not d.added and not d.removed and not d.modified
    assert d.moved


def test_novelty_boost_and_churn_penalty_are_deterministic() -> None:
    a = _page("careers.html", "https://www.acme-cloud.example/careers")
    b = _page("careers_v2.html", "https://www.acme-cloud.example/careers")
    base = compare(a.blocks, b.blocks, surface="careers", before_text=a.text, after_text=b.text).significance
    novel = compare(a.blocks, b.blocks, surface="careers", before_text=a.text, after_text=b.text, history={"consecutive_unchanged": 50}).significance
    churn = compare(a.blocks, b.blocks, surface="careers", before_text=a.text, after_text=b.text, history={"observation_count": 20, "change_count": 15}).significance
    assert novel > base > churn
    assert base == compare(a.blocks, b.blocks, surface="careers", before_text=a.text, after_text=b.text).significance