# File: src/data_loader.py
# Purpose: Generate and load synthetic hospital appointment data for testing

import json
import random
from pathlib import Path
from datetime import datetime, timedelta

import sys
sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
from config import SYNTHETIC_DATA_PATH, DEPARTMENTS, AVAILABLE_SLOTS


def generate_synthetic_appointments(n: int = 50) -> list[dict]:
    """
    Generate n synthetic appointment records to simulate a hospital database.
    Each record has: appointment_id, patient_name, department, date, slot, status.
    """
    records = []
    base_date = datetime.today()

    for i in range(1, n + 1):
        offset_days = random.randint(0, 14)
        appt_date = (base_date + timedelta(days=offset_days)).strftime("%Y-%m-%d")
        records.append({
            "appointment_id": f"APT-{10000 + i}",
            "patient_name": f"Patient_{i}",
            "department": random.choice(DEPARTMENTS),
            "date": appt_date,
            "slot": random.choice(AVAILABLE_SLOTS),
            "status": "booked",
            "doctor": f"Dr. Sample_{random.randint(1, 5)}",
        })

    return records


def save_synthetic_data(n: int = 50):
    """Save generated appointments to disk for mock API use."""
    SYNTHETIC_DATA_PATH.parent.mkdir(parents=True, exist_ok=True)
    records = generate_synthetic_appointments(n)
    with open(SYNTHETIC_DATA_PATH, "w") as f:
        json.dump(records, f, indent=2)
    print(f"Saved {n} synthetic appointments to {SYNTHETIC_DATA_PATH}")
    return records


def load_appointments() -> list[dict]:
    """Load existing appointment data from disk."""
    if not SYNTHETIC_DATA_PATH.exists():
        print("No data found. Generating synthetic data...")
        return save_synthetic_data()
    with open(SYNTHETIC_DATA_PATH) as f:
        return json.load(f)


if __name__ == "__main__":
    records = save_synthetic_data(n=50)
    print(f"Sample record: {records[0]}")