auth_manager.py

import sqlite3
import hashlib
import db_logger

DB_FILE = db_logger.DB_FILE

# Default users to seed (User bawaan)
DEFAULT_USERS = {
    "free": {"password": "free", "role": "free"},
    "premium": {"password": "premium", "role": "premium"},
    "dev": {"password": "dev", "role": "developer"}
}

def hash_password(password):
    """Mengenkripsi password menggunakan SHA-256."""
    return hashlib.sha256(password.encode()).hexdigest()

def seed_users():
    """
    Memasukkan user default ke database jika belum ada.
    Password akan otomatis di-hash.
    """
    conn = sqlite3.connect(DB_FILE)
    c = conn.cursor()
    
    for username, data in DEFAULT_USERS.items():
        try:
            hashed_pw = hash_password(data['password'])
            # INSERT OR IGNORE akan melewati jika username sudah ada (karena constraint UNIQUE)
            c.execute("INSERT OR IGNORE INTO users (username, password, role) VALUES (?, ?, ?)", 
                      (username, hashed_pw, data['role']))
        except Exception as e:
            print(f"Error seeding user {username}: {e}")
            
    conn.commit()
    conn.close()

# Jalankan seeding saat modul diimpor
seed_users()

def authenticate(username, password):
    """
    Memvalidasi kredensial login user.
    Returns: (is_valid, role, message)
    """
    username = username.strip()
    
    try:
        conn = sqlite3.connect(DB_FILE)
        c = conn.cursor()
        c.execute("SELECT password, role FROM users WHERE username = ?", (username,))
        result = c.fetchone()
        conn.close()
        
        if result:
            stored_password_hash, role = result
            input_password_hash = hash_password(password)
            
            # Cek Kompatibilitas: Jika password di DB bukan hash (misal sisa versi lama)
            if len(stored_password_hash) != 64 and stored_password_hash == password:
                return True, role, f"✅ Welcome, {username} ({role})"
            
            # Cek Hash
            if stored_password_hash == input_password_hash:
                return True, role, f"✅ Welcome, {username} ({role})"
            else:
                return False, None, "❌ Invalid password"
        else:
            return False, None, "❌ User not found"
            
    except Exception as e:
        return False, None, f"❌ System Error: {e}"

def add_user(username, password, role):
    """Menambahkan user baru ke database dengan password terenkripsi."""
    username = username.strip()
    if not username or not password or not role:
        return False, "All fields are required."
        
    try:
        conn = sqlite3.connect(DB_FILE)
        c = conn.cursor()
        hashed_pw = hash_password(password)
        c.execute("INSERT INTO users (username, password, role) VALUES (?, ?, ?)", (username, hashed_pw, role))
        conn.commit()
        conn.close()
        return True, f"User '{username}' created successfully."
    except sqlite3.IntegrityError:
        return False, f"User '{username}' already exists."
    except Exception as e:
        return False, f"Error: {e}"

def list_users():
    """Menampilkan daftar semua user (tanpa password) dalam bentuk DataFrame."""
    try:
        conn = sqlite3.connect(DB_FILE)
        import pandas as pd
        df = pd.read_sql_query("SELECT id, username, role FROM users", conn)
        conn.close()
        return df
    except Exception as e:
        print(f"Error listing users: {e}")
        return None

def delete_user(username):
    """Menghapus user berdasarkan username."""
    try:
        conn = sqlite3.connect(DB_FILE)
        c = conn.cursor()
        c.execute("DELETE FROM users WHERE username = ?", (username,))
        conn.commit()
        rows = c.rowcount
        conn.close()
        if rows > 0:
            return True, f"User '{username}' deleted."
        else:
            return False, f"User '{username}' not found."
    except Exception as e:
        return False, f"Error: {e}"