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"""Generate synthetic noise pollution & urban health dataset for SSA.

Research-based parameterization:
- WHO (2024): Environmental noise causes cardiovascular, mental health,
  sleep disturbance; updated disability weights for noise exposure.
- WHO guidelines: 53 dB Lden road traffic; 45 dB Lnight for sleep.
- Nature (2022): Traffic noise quantified in South African cities.
- PMC11221953: Nigerian noise levels and health perceptions - annoyance,
  mental stress, sleep disturbance, hearing loss, cardiovascular effects.
- IntechOpen (2022): Noise policy challenges in developing countries;
  most lack enforceable legislation.
"""

from __future__ import annotations

from pathlib import Path

import numpy as np
import pandas as pd

SEED = 42
N_PER_SCENARIO = 10_000

YEAR_RANGE = np.arange(2010, 2025)
YEAR_WEIGHTS = np.linspace(0.85, 1.3, len(YEAR_RANGE))
YEAR_WEIGHTS = YEAR_WEIGHTS / YEAR_WEIGHTS.sum()

SCENARIOS = {
    "megacity_traffic": {
        "setting_probs": {"commercial_road": 0.35, "residential_road": 0.30,
                          "industrial": 0.15, "market": 0.20},
        "noise_source_probs": {"road_traffic": 0.40, "generators": 0.20, "industry": 0.15,
                               "entertainment": 0.10, "construction": 0.10, "religious": 0.05},
        "lden_mean": 72, "lden_sd": 10,
        "lnight_mean": 58, "lnight_sd": 8,
        "hearing_loss_prev": 0.12,
        "hypertension_noise_pct": 0.08,
        "sleep_disturbance_pct": 0.35,
        "noise_regulation": 0.15,
    },
    "secondary_city_mixed": {
        "setting_probs": {"commercial_road": 0.30, "residential": 0.35,
                          "market": 0.20, "industrial": 0.15},
        "noise_source_probs": {"road_traffic": 0.30, "generators": 0.25, "entertainment": 0.15,
                               "religious": 0.10, "construction": 0.10, "industry": 0.10},
        "lden_mean": 65, "lden_sd": 10,
        "lnight_mean": 52, "lnight_sd": 8,
        "hearing_loss_prev": 0.08,
        "hypertension_noise_pct": 0.05,
        "sleep_disturbance_pct": 0.25,
        "noise_regulation": 0.08,
    },
    "periurban_emerging": {
        "setting_probs": {"residential": 0.40, "market": 0.25,
                          "peri_urban_road": 0.20, "industrial_fringe": 0.15},
        "noise_source_probs": {"road_traffic": 0.25, "generators": 0.20, "entertainment": 0.15,
                               "religious": 0.15, "agriculture": 0.10, "construction": 0.15},
        "lden_mean": 58, "lden_sd": 10,
        "lnight_mean": 45, "lnight_sd": 8,
        "hearing_loss_prev": 0.05,
        "hypertension_noise_pct": 0.03,
        "sleep_disturbance_pct": 0.15,
        "noise_regulation": 0.05,
    },
}

SCENARIO_FILES = {
    "megacity_traffic": "noise_megacity.csv",
    "secondary_city_mixed": "noise_secondary_city.csv",
    "periurban_emerging": "noise_periurban.csv",
}


def _choice(rng, prob_map):
    keys = list(prob_map.keys())
    weights = np.array(list(prob_map.values()), dtype=float)
    weights = weights / weights.sum()
    return rng.choice(keys, p=weights)


def _simulate_scenario(name, params, seed):
    rng = np.random.default_rng(seed)
    records = []

    for idx in range(N_PER_SCENARIO):
        year = int(rng.choice(YEAR_RANGE, p=YEAR_WEIGHTS))
        setting = _choice(rng, params["setting_probs"])
        age = int(np.clip(rng.normal(32, 15), 5, 75))
        sex = rng.choice(["male", "female"], p=[0.50, 0.50])
        is_child = int(age < 15)
        occupation = rng.choice(["outdoor_worker", "indoor_worker", "student", "homemaker", "vendor"],
                                p=[0.25, 0.20, 0.20, 0.20, 0.15])

        noise_source = _choice(rng, params["noise_source_probs"])
        distance_to_source_m = float(np.clip(rng.exponential(50), 5, 500))
        proximity_factor = max(0.5, 1.0 - distance_to_source_m / 200)

        lden = float(np.clip(
            rng.normal(params["lden_mean"] * proximity_factor, params["lden_sd"]), 35, 110))
        lnight = float(np.clip(
            rng.normal(params["lnight_mean"] * proximity_factor, params["lnight_sd"]), 25, 90))

        exceeds_who_lden = int(lden > 53)
        exceeds_who_lnight = int(lnight > 45)
        exceeds_85db = int(lden > 85)

        exposure_years = int(np.clip(rng.normal(8, 5), 0, 30))
        daily_exposure_hours = float(np.clip(rng.normal(8, 3), 1, 16))

        uses_hearing_protection = int(rng.random() < 0.05)

        risk_mult = lden / 53
        hearing_loss = int(rng.random() < np.clip(
            params["hearing_loss_prev"] * risk_mult * (exposure_years / 10), 0, 0.35))
        tinnitus = int(rng.random() < np.clip(0.05 + risk_mult * 0.04, 0, 0.25))

        hypertension = int(age >= 25 and rng.random() < np.clip(
            params["hypertension_noise_pct"] * risk_mult, 0, 0.20))
        cardiovascular = int(age >= 35 and hypertension and rng.random() < 0.15)

        sleep_disturbance = int(rng.random() < np.clip(
            params["sleep_disturbance_pct"] * (lnight / 45), 0, 0.60))
        annoyance = int(rng.random() < np.clip(0.20 + risk_mult * 0.15, 0, 0.70))
        stress_anxiety = int(rng.random() < np.clip(0.10 + risk_mult * 0.08, 0, 0.35))
        concentration_difficulty = int(rng.random() < np.clip(0.08 + risk_mult * 0.06, 0, 0.30))

        child_learning = int(is_child and rng.random() < np.clip(risk_mult * 0.08, 0, 0.20))

        noise_complaint = int(annoyance and rng.random() < 0.10)
        noise_regulation = int(rng.random() < params["noise_regulation"])
        noise_monitoring = int(rng.random() < 0.05)

        record = {
            "record_id": f"{name[:3].upper()}-{idx:05d}",
            "scenario": name,
            "year": year,
            "setting": setting,
            "age": age,
            "sex": sex,
            "is_child": is_child,
            "occupation": occupation,
            "noise_source": noise_source,
            "distance_to_source_m": round(distance_to_source_m, 0),
            "lden_db": round(lden, 1),
            "lnight_db": round(lnight, 1),
            "exceeds_who_lden_53": exceeds_who_lden,
            "exceeds_who_lnight_45": exceeds_who_lnight,
            "exceeds_85db": exceeds_85db,
            "exposure_years": exposure_years,
            "daily_exposure_hours": round(daily_exposure_hours, 1),
            "uses_hearing_protection": uses_hearing_protection,
            "hearing_loss": hearing_loss,
            "tinnitus": tinnitus,
            "hypertension": hypertension,
            "cardiovascular": cardiovascular,
            "sleep_disturbance": sleep_disturbance,
            "annoyance": annoyance,
            "stress_anxiety": stress_anxiety,
            "concentration_difficulty": concentration_difficulty,
            "child_learning": child_learning,
            "noise_complaint": noise_complaint,
            "noise_regulation": noise_regulation,
            "noise_monitoring": noise_monitoring,
        }
        records.append(record)

    return pd.DataFrame(records)


def main():
    output_dir = Path("data")
    output_dir.mkdir(parents=True, exist_ok=True)
    for idx, (name, params) in enumerate(SCENARIOS.items()):
        df = _simulate_scenario(name, params, SEED + idx * 211)
        df.to_csv(output_dir / SCENARIO_FILES[name], index=False)
        print(f"Saved {name} -> {SCENARIO_FILES[name]}")


if __name__ == "__main__":
    main()