from flask import Flask, request, render_template, jsonify, redirect, send_from_directory
from datenbankverbindung import lade_db_config, speichere_db_config, teste_verbindung, initialisiere_admin_user
from datetime import datetime, timedelta
from jwt import decode, ExpiredSignatureError, InvalidTokenError

import time
import os
import jwt

app = Flask(__name__)
app.template_folder = "templates"
SECRET_KEY = "bitte_hier_dein_geheimes_passwort_setzen"  # Achtung: später z. B. aus .env

CONFIG_PATH = "config/db_config.json"
MAX_WAIT = 30  # In Sekunden
WAIT_INTERVAL = 10

def ist_konfiguriert():
    return os.path.exists(CONFIG_PATH)

def versuche_verbindung_mit_warten():
    elapsed = 0
    if not ist_konfiguriert():
        return False
    config = lade_db_config()
    while not teste_verbindung(config) and elapsed < MAX_WAIT:
        print(f"[INFO] DB nicht erreichbar – warte {WAIT_INTERVAL}s...")
        time.sleep(WAIT_INTERVAL)
        elapsed += WAIT_INTERVAL
    return elapsed < MAX_WAIT

@app.route('/api/status')
def status():
    if not ist_konfiguriert():
        return jsonify({"status": "init", "db_connected": False})
    elif teste_verbindung(lade_db_config()):
        return jsonify({"status": "ready", "db_connected": True})
    else:
        return jsonify({"status": "error", "db_connected": False})

@app.route('/setup', methods=['GET', 'POST'])
def setup():
    if request.method == 'POST':
        db_config = {
            "host": request.form['host'],
            "port": int(request.form['port']),
            "user": request.form['user'],
            "password": request.form['password'],
            "database": request.form['database']
        }
        speichere_db_config(db_config)
        if teste_verbindung(db_config):
            initialisiere_admin_user(db_config)  # <- das hier NEU
            return redirect('/')

        else:
            return "Verbindung fehlgeschlagen. Bitte zurück und prüfen.", 500
    return render_template('setup.html')

@app.route('/', defaults={'path': ''})
@app.route('/<path:path>')
def serve_react(path):
    if not ist_konfiguriert() or not teste_verbindung(lade_db_config()):
        return redirect('/setup')

    # setup und API dürfen nicht von React überdeckt werden
    if path.startswith('setup') or path.startswith('api'):
        return redirect(f'/{path}')

    # Pfad zu frontend/dist absolut auflösen
    dist_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'frontend', 'dist'))
    file_path = os.path.join(dist_dir, path)

    if path and os.path.exists(file_path):
        return send_from_directory(dist_dir, path)
    else:
        return send_from_directory(dist_dir, 'index.html')

@app.route('/api/login', methods=['POST'])
def login():
    from mysql.connector import connect
    from werkzeug.security import check_password_hash

    data = request.get_json()
    username = data.get('username')
    password = data.get('password')

    try:
        config = lade_db_config()
        conn = connect(**config)
        cursor = conn.cursor(dictionary=True)
        cursor.execute("SELECT * FROM users WHERE username = %s", (username,))
        user = cursor.fetchone()
        cursor.close()
        conn.close()

        if user and check_password_hash(user['password'], password):
            # JWT generieren
            payload = {
                "username": user['username'],
                "role": user['role'],
                "exp": datetime.utcnow() + timedelta(minutes=60)  # Token läuft nach 60 Min ab
            }
            token = jwt.encode(payload, SECRET_KEY, algorithm="HS256")

            return jsonify({
                "token": token,
                "role": user['role']
            })

        return jsonify({"message": "Login fehlgeschlagen"}), 401

    except Exception as e:
        print("[Login-Fehler]", e)
        return jsonify({"message": "Serverfehler"}), 500


@app.route('/api/logout', methods=['POST'])
def logout():
    # Aktuell macht das nichts, aber der Client bekommt Bestätigung
    return jsonify({"message": "Logout erfolgreich"})

def verify_token():
    auth_header = request.headers.get("Authorization", "")
    if not auth_header.startswith("Bearer "):
        return None

    token = auth_header.replace("Bearer ", "")
    try:
        decoded = decode(token, SECRET_KEY, algorithms=["HS256"])
        return decoded  # enthält z. B. username, role, exp
    except ExpiredSignatureError:
        print("[JWT] Token abgelaufen")
        return None
    except InvalidTokenError:
        print("[JWT] Ungültiger Token")
        return None

@app.route('/api/tools/md5', methods=['POST'])
def md5_tool():
    user = verify_token()
    if not user:
        return jsonify({"message": "Nicht autorisiert"}), 401

    data = request.get_json()
    input_text = data.get("text", "")
    
    import hashlib
    result = hashlib.md5(input_text.encode()).hexdigest()

    return jsonify({
        "username": user['username'],
        "hash": result
    })


if __name__ == '__main__':
    os.makedirs("config", exist_ok=True)
    app.run(host='127.0.0.1', port=5000)