api.py

"""
AIBalance API — recommandation sobre par usage
Version legere : charge des fichiers pre-calcules (pas de parquet 4 Go).
Pre-requis : lancer export_for_api.py une fois en local.
Endpoint : POST /recommend  {prompt, mode, top_n}
"""

from flask import Flask, request, jsonify
from flask_cors import CORS
from sentence_transformers import SentenceTransformer
import pandas as pd, re, time, os, pickle, json, joblib

app = Flask(__name__)
CORS(app)

# ── Config ──
EMBEDDING_MODEL = "Lajavaness/bilingual-embedding-small"
DELTA = 0.03
MEDIAN_ENERGY = 0.66
MODEL_PATH = "outputs_v3/api_clf.joblib"

# ── Globals ──
embedder = None
clf = None
reco_table = {}
profil_map = {}

FAMILY_MAP = {
    'Natural Science & Formal Science & Technology': 'code',
    'Education': 'education', 'Arts & Culture': 'creation', 'Arts': 'creation',
    'Entertainment & Travel & Hobby': 'creation', 'Food & Drink & Cooking': 'creation',
}


def get_task_family(cat):
    return FAMILY_MAP.get(cat, 'analysis' if 'Business' in cat or 'Law' in cat or 'Politic' in cat else 'education' if 'Education' in cat else 'default')


def extract_complexity(prompt):
    p = str(prompt)
    return {
        'n_words': len(p.split()),
        'is_code': int(bool(re.search(r'\b(code|python|java|sql|html|css|script|function|class|def |import)\b', p, re.I))),
        'n_questions': p.count('?'),
    }


def boot():
    """Charge les fichiers pre-calcules + embedder + classifieur."""
    global embedder, clf, reco_table, profil_map

    print("Boot API (mode leger)...")
    t0 = time.time()

    # embedder
    device = 'cpu'
    print(f"  Device : {device}")
    embedder = SentenceTransformer(EMBEDDING_MODEL, trust_remote_code=True, device=device)

    # classifieur
    clf_obj = joblib.load(MODEL_PATH)
    print(f"  Classifieur charge depuis {MODEL_PATH}")

    # reco_table pre-calculee
    with open('outputs_v3/api_reco_table.pkl', 'rb') as f:
        reco_table.update(pickle.load(f))
    print(f"  Reco table : {len(reco_table)} categories")

    # profil map
    with open('outputs_v3/api_profil_map.json', 'r') as f:
        profil_map.update(json.load(f))

    print(f"Boot OK ({time.time() - t0:.1f}s)")
    return clf_obj


def classify_prompt(prompt):
    emb = embedder.encode([prompt], convert_to_numpy=True, normalize_embeddings=True)
    return clf.predict(emb)[0]


def recommander(prompt, top_n=3, mode='balanced'):
    MODES = {'performance': (0.8, 0.2), 'green': (0.2, 0.8), 'balanced': (0.5, 0.5)}
    alpha, beta = MODES.get(mode, (0.5, 0.5))

    category = classify_prompt(prompt)
    family = get_task_family(category)
    cx = extract_complexity(prompt)

    if category in reco_table:
        candidates = reco_table[category].copy()
        qual_col = 'combined_quality'
    else:
        found = False
        for orig in reco_table:
            if get_task_family(orig) == get_task_family(category):
                candidates = reco_table[orig].copy()
                qual_col = 'combined_quality'
                found = True
                break
        if not found:
            candidates = pd.DataFrame()
            qual_col = 'win_rate'

    if len(candidates) == 0:
        return {'error': 'Pas de candidats pour cette categorie', 'category': category}

    # score mode
    q = candidates[qual_col]
    q_norm = (q - q.min()) / (q.max() - q.min()) if q.max() > q.min() else 0.5
    e = candidates['wh_per_1k_tok']
    s_norm = 1 - (e - e.min()) / (e.max() - e.min()) if e.max() > e.min() else 0.5
    candidates['mode_score'] = alpha * q_norm + beta * s_norm

    # filtre DELTA
    best_q = candidates[qual_col].max()
    equivalent = candidates[candidates[qual_col] >= best_q - DELTA]

    # filtre complexite
    is_complex = cx['n_words'] > 100 or cx['is_code'] or cx['n_questions'] > 2
    if is_complex:
        wr_col = 'win_rate_cat' if 'win_rate_cat' in equivalent.columns else 'win_rate'
        median_wr = candidates[wr_col].median()
        complex_ok = equivalent[equivalent[wr_col] >= median_wr]
        if len(complex_ok) > 0:
            equivalent = complex_ok

    top = equivalent.nlargest(top_n, 'mode_score')

    # resultats
    results = []
    for _, r in top.iterrows():
        wr = r.get('win_rate_cat', r.get('win_rate', 0))
        cq = r.get(qual_col, wr)
        energy = r['wh_per_1k_tok']
        gain_vs_median = (1 - energy / MEDIAN_ENERGY) * 100 if MEDIAN_ENERGY > energy else 0
        results.append({
            'model': r['model'],
            'energy_wh': round(energy, 3),
            'win_rate': round(float(wr) * 100, 1),
            'quality': round(float(cq), 3),
            'profil': profil_map.get(r['model'], '?'),
            'gain_vs_median': round(gain_vs_median, 0),
        })

    return {
        'category': category,
        'family': family,
        'complexity': 'complexe' if is_complex else 'simple',
        'n_words': cx['n_words'],
        'mode': mode,
        'alpha': alpha,
        'beta': beta,
        'n_candidates': len(candidates),
        'n_equivalent': len(equivalent),
        'delta': DELTA,
        'recommendations': results,
    }


@app.route('/recommend', methods=['POST'])
def api_recommend():
    data = request.get_json()
    prompt = data.get('prompt', '')
    mode = data.get('mode', 'balanced')
    top_n = data.get('top_n', 3)

    if not prompt.strip():
        return jsonify({'error': 'Prompt vide'}), 400

    result = recommander(prompt, top_n=top_n, mode=mode)
    return jsonify(result)


@app.route('/health', methods=['GET'])
def health():
    return jsonify({
        'status': 'ok',
        'categories': len(reco_table),
        'models': sum(len(t) for t in reco_table.values()),
    })


if __name__ == '__main__':
    clf = boot()
    port = int(os.environ.get('PORT', 7860))
    print(f"\nAPI prete : http://localhost:{port}")
    print("  POST /recommend  {prompt, mode, top_n}")
    print("  GET  /health")
    app.run(host='0.0.0.0', port=port, debug=False)