🚀 Day 5：打造「MVC 模組化重構與 CLI 版發布 (Django Ready MVT 架構)」

"""
====================================================================
 高中生極簡終端機記帳本 (CLI 版 - Django 銜接預備架構)
 系統架構：採 MVT (Model - View - Template/Controller) 模組化設計
====================================================================
"""

import json
import os
from datetime import datetime

DATA_FILE = "expenses.json"

# ==========================================
# 📦 [MODEL 區塊] 資料庫與持久化操作 (對應 Django models.py / Database)
# ==========================================

def model_load_data():
    """ 讀取 JSON 資料檔 (模擬 Django ORM 物件查詢) """
    if not os.path.exists(DATA_FILE):
        return []
    try:
        with open(DATA_FILE, "r", encoding="utf-8") as f:
            return json.load(f)
    except Exception:
        return []

def model_save_data(records):
    """ 儲存資料至 JSON 檔案 (模擬 Django .save() 寫入資料庫) """
    with open(DATA_FILE, "w", encoding="utf-8") as f:
        json.dump(records, f, ensure_ascii=False, indent=4)

def model_add_record(records, item, price, category):
    """ 新增一筆紀錄 (模擬 Model 創立紀錄) """
    record = {
        "id": len(records) + 1,
        "item": item,
        "price": price,
        "category": category,
        "date": datetime.now().strftime("%Y-%m-%d %H:%M")
    }
    records.append(record)
    model_save_data(records)
    return record

def model_delete_record(records, index):
    """ 刪除指定索引的記錄 """
    if 0 <= index < len(records):
        deleted = records.pop(index)
        for i, r in enumerate(records):
            r["id"] = i + 1
        model_save_data(records)
        return deleted
    return None

# ==========================================
# 🎨 [VIEW 區塊] 介面渲染與印出 (對應 Django Templates / HTML)
# ==========================================

def view_header():
    print("\n" + "=" * 45)
    print("     🚀 酷炫 Python 終端機記帳本 🚀")
    print("=" * 45)

def view_menu():
    view_header()
    print("  [1] ➕ 新增消費紀錄")
    print("  [2] 📊 查看所有明細與統計")
    print("  [3] 🔍 依分類篩選紀錄")
    print("  [4] ❌ 刪除特定消費紀錄")
    print("  [5] 💾 儲存並退出系統")
    print("=" * 45)

def view_render_list(records):
    """ 渲染帳務明細 (模擬 Django HTML {% for %} 走訪) """
    if not records:
        print("\n📭 目前尚無任何記帳資料！")
        return

    print("\n=== 💰 您的記帳明細列表 ===")
    print(f"{'編號':<5}{'品項':<12}{'分類':<10}{'金額':<8}{'時間'}")
    print("-" * 50)
    
    total = 0
    for r in records:
        print(f"{r['id']:<5}{r['item']:<12}{r['category']:<10}${r['price']:<7}{r['date']}")
        total += r["price"]
        
    print("-" * 50)
    print(f"💵 總計累計消費：${total} 元\n")

# ==========================================
# ⚙️ [CONTROLLER / ROUTER 區塊] 控制邏輯 (對應 Django views.py / urls.py)
# ==========================================

def handle_add(records):
    """ 處理新增消費邏輯 """
    item = input("👉 請輸入消費名稱 (例如: 珍珠奶茶): ").strip()
    if not item:
        print("⚠️ 名稱不能為空！")
        return

    price_input = input("👉 請輸入金額: ").strip()
    if not price_input.isdigit():
        print("❌ 錯誤：金額必須是純數字！")
        return
    
    category = input("👉 請輸入分類 (例如: 餐飲/娛樂/學習): ").strip() or "一般"

    record = model_add_record(records, item, int(price_input), category)
    print(f"✅ 成功寫入：{record['item']} ${record['price']} 元 [{record['category']}]")

def handle_filter(records):
    """ 處理按分類搜尋邏輯 """
    cat = input("🔍 請輸入要搜尋的分類名稱: ").strip()
    filtered = [r for r in records if r["category"] == cat]
    print(f"\n🔎 搜尋分類結果: '{cat}'")
    view_render_list(filtered)

def handle_delete(records):
    """ 處理刪除邏輯 """
    view_render_list(records)
    if not records:
        return
    
    idx_input = input("❌ 請輸入要刪除的編號 (ID): ").strip()
    if idx_input.isdigit():
        idx = int(idx_input) - 1
        deleted = model_delete_record(records, idx)
        if deleted:
            print(f"🗑️ 已成功刪除：{deleted['item']} ${deleted['price']} 元")
        else:
            print("⚠️ 找不到該編號！")
    else:
        print("❌ 輸入無效，請輸入數字 ID。")

# ==========================================
# 🏁 [MAIN 區塊] 程式入口 (主生命週期)
# ==========================================

def main():
    records = model_load_data()
    while True:
        view_menu()
        choice = input("👉 請選擇功能選項 (1-5): ").strip()

        if choice == "1":
            handle_add(records)
        elif choice == "2":
            view_render_list(records)
        elif choice == "3":
            handle_filter(records)
        elif choice == "4":
            handle_delete(records)
        elif choice == "5":
            print("\n💾 系統資料已保存，期待下次運算！再見！👋")
            break
        else:
            print("⚠️ 無效的選項，請輸入數字 1 至 5！")

if __name__ == "__main__":
    main()