import json
from difflib import SequenceMatcher

def load_diseases():
    with open("diseases.json", "r", encoding="utf-8") as f:
        return json.load(f)

def diagnose_symptoms(user_input):
    diseases = load_diseases()
    results = []
    user_symptoms = [s.strip() for s in user_input.split(",")]
    for disease, info in diseases.items():
        match_score = sum(
            SequenceMatcher(None, sym.lower(), us.lower()).ratio()
            for sym in info["symptoms"]
            for us in user_symptoms
        ) / (len(info["symptoms"]) * len(user_symptoms))
        if match_score > 0.2:
            results.append({
                "disease": disease,
                "score": match_score,
                "source": info["source"]
            })
    results.sort(key=lambda x: x["score"], reverse=True)
    return results[:5]