"""Unit tests for the Deal Intelligence Engine (pure functions, no network)."""

import os
import sys
from datetime import date

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
os.environ.setdefault("TRAVELPAYOUTS_TOKEN", "test-token")

from flights import intelligence as iq

PASS = 0


def check(name, cond):
    global PASS
    assert cond, f"FAIL: {name}"
    PASS += 1
    print(f"  ok  {name}")


# ── fair_price: hedonic baseline sanity ──────────────────────────────────────
short = iq.fair_price(500)            # TLV->ATH-ish
medium = iq.fair_price(3200)          # TLV->LON-ish
long = iq.fair_price(9100)            # TLV->JFK-ish
check("baseline increases with distance", short < medium < long)
check("short-haul in sane range", 60 <= short <= 160)
check("long-haul in sane range", 300 <= long <= 900)
per_km_short = short / 500
per_km_long = long / 9100
check("economies of distance (concave curve)", per_km_long < per_km_short)

july_fri = iq.fair_price(3200, date(2026, 7, 3))      # Friday in July (peak+peak)
feb_tue = iq.fair_price(3200, date(2026, 2, 10))      # Tuesday in February (trough)
check("July Friday priced above February Tuesday", july_fri > feb_tue)
check("round trip < 2x one-way", iq.fair_price(3200, round_trip=True) < 2 * iq.fair_price(3200))

# ── deal_score: monotone, labeled, explainable ───────────────────────────────
steal = iq.deal_score(0.5 * medium, medium)
fairp = iq.deal_score(medium, medium)
rip = iq.deal_score(1.8 * medium, medium)
check("half typical scores ~95", steal["score"] >= 90)
check("typical price scores 60", fairp["score"] == 60)
check("1.8x typical floors", rip["score"] <= 10)
check("scores monotone", steal["score"] > fairp["score"] > rip["score"])
check("labels attached", steal["label"] == "exceptional deal" and fairp["label"] == "typical price")
check("vs_typical_pct signed", steal["vs_typical_pct"] == -50 and rip["vs_typical_pct"] == 80)
check("degenerate fair handled", iq.deal_score(100, 0)["score"] is None)

# ── annotate_offers: uses airport coords, skips unknowns ─────────────────────
offers = [
    {"price": 120.0, "origin": "TLV", "destination": "ATH", "date": "2026-08-10", "round_trip": False},
    {"price": None, "origin": "TLV", "destination": "ATH", "date": "2026-08-10"},          # unpriced
    {"price": 99.0, "origin": "XXQ", "destination": "ZZQ", "date": "2026-08-10"},          # unknown route
]
iq.annotate_offers(offers)
check("priced known route annotated", offers[0].get("deal", {}).get("score") is not None)
check("unpriced offer skipped", "deal" not in offers[1])
check("unknown route skipped, no crash", "deal" not in offers[2])

# ── date_insights: fly-Tuesday-save-$X analytics ─────────────────────────────
month = [
    {"price": 210.0, "date": "2026-08-03"},  # Monday
    {"price": 150.0, "date": "2026-08-04"},  # Tuesday   <- cheapest
    {"price": 205.0, "date": "2026-08-07"},  # Friday
    {"price": 260.0, "date": "2026-08-08"},  # Saturday  <- priciest
    {"price": 155.0, "date": "2026-08-11"},  # Tuesday
]
ins = iq.date_insights(month)
check("cheapest date found", ins["cheapest_date"] == "2026-08-04" and ins["cheapest_date_price"] == 150.0)
check("flex savings computed", ins["max_flex_savings"] == 110.0)
check("best weekday is Tuesday", ins.get("best_weekday") == "Tuesday")
check("weekday savings positive", ins.get("weekday_avg_savings", 0) > 0)
check("insufficient data -> None", iq.date_insights([{"price": 100.0, "date": "2026-08-03"}]) is None)

# ── wander_scores: utility per dollar, best = 100 ────────────────────────────
alts = [
    {"similarity": 0.90, "cheapest_flight": {"price": 300.0}},   # 0.0030 per $
    {"similarity": 0.80, "cheapest_flight": {"price": 160.0}},   # 0.0050 per $  <- best value
    {"similarity": 0.95, "cheapest_flight": {"price": None}},    # unpriced -> no score
]
iq.wander_scores(alts)
check("best value scores 100", alts[1]["wander_score"] == 100)
check("worse value scaled down", alts[0]["wander_score"] == 60)
check("unpriced alt unscored", "wander_score" not in alts[2])
check("empty set safe", iq.wander_scores([]) == [])

# ── scan_start_dates: multi-month cheapest-date engine ───────────────────────
d0 = date(2026, 11, 20)
scan = iq.scan_start_dates(d0, 3)
check("scan keeps start date", scan[0] == d0)
check("scan hits following month firsts", scan[1] == date(2026, 12, 1))
check("scan wraps the year", scan[2] == date(2027, 1, 1))
check("scan n=1 is just start", iq.scan_start_dates(d0, 1) == [d0])

# ── price_calendar: cheapest per date, date-sorted ───────────────────────────
cal = iq.price_calendar([
    {"price": 220.0, "date": "2026-08-10", "stops": 1},
    {"price": 180.0, "date": "2026-08-10", "stops": 0},   # cheaper same-day wins
    {"price": 150.0, "date": "2026-08-04", "stops": 0},
    {"price": None, "date": "2026-08-05"},                 # unpriced skipped
    {"price": 300.0, "date": "not-a-date"},                # junk skipped
])
check("calendar keeps cheapest per date", [c["price"] for c in cal] == [150.0, 180.0])
check("calendar date-sorted", [c["date"] for c in cal] == ["2026-08-04", "2026-08-10"])
check("calendar carries stops", cal[1]["stops"] == 0)

print(f"\nALL {PASS} CHECKS PASSED")