Jobsheet 06: File Persistence & Mini Proyek

import json
import os
from datetime import datetime

FILE_KATALOG = "katalog.json"

class Produk:
    def __init__(self, kode: str, nama: str, harga: float, stok: int):
        self.kode = kode
        self.nama = nama
        self.harga = harga
        self.stok = stok

    def to_dict(self):
        return {"kode": self.kode, "nama": self.nama, "harga": self.harga, "stok": self.stok}

class TokoPOS:
    def __init__(self):
        self.katalog = {}
        self.muat_katalog()

    def muat_katalog(self):
        if not os.path.exists(FILE_KATALOG):
            # Data Awal Standar
            default_data = {
                "P01": {"kode": "P01", "nama": "Kopi Arabika 250g", "harga": 65000, "stok": 20},
                "P02": {"kode": "P02", "nama": "Susu UHT 1 Liter", "harga": 22000, "stok": 15},
                "P03": {"kode": "P03", "nama": "Roti Gandum", "harga": 18000, "stok": 10}
            }
            with open(FILE_KATALOG, "w", encoding="utf-8") as f:
                json.dump(default_data, f, indent=4)

        try:
            with open(FILE_KATALOG, "r", encoding="utf-8") as f:
                raw = json.load(f)
                for k, v in raw.items():
                    self.katalog[k] = Produk(v["kode"], v["nama"], v["harga"], v["stok"])
        except Exception as e:
            print(f"[ERROR] Gagal membaca katalog: {e}")

    def simpan_katalog(self):
        data = {k: v.to_dict() for k, v in self.katalog.items()}
        with open(FILE_KATALOG, "w", encoding="utf-8") as f:
            json.dump(data, f, indent=4)

    def tampilkan_katalog(self):
        print("\n" + "="*50)
        print("               KATALOG PRODUK TOKO                ")
        print("="*50)
        print(f"{'KODE':<6} | {'NAMA PRODUK':<22} | {'HARGA':<10} | {'STOK':<4}")
        print("-"*50)
        for p in self.katalog.values():
            print(f"{p.kode:<6} | {p.nama:<22} | Rp {p.harga:>7,.0f} | {p.stok:>4}")
        print("="*50)

# Inisialisasi Engine
app_pos = TokoPOS()
app_pos.tampilkan_katalog()