🗄️ IndexedDB Introduction — Browser Mein Database

// Database open (ya create) karo
const request = indexedDB.open("BiryaniDB", 1);

// Pehle open pe object store banao
request.onupgradeneeded = (event) => {
  const db = event.target.result;
  
  if (!db.objectStoreNames.contains("orders")) {
    const store = db.createObjectStore("orders", { keyPath: "id", autoIncrement: true });
    store.createIndex("itemName", "itemName", { unique: false });
    store.createIndex("status", "status", { unique: false });
  }
};

request.onsuccess = (event) => {
  const db = event.target.result;
  console.log("Database opened:", db.name);
};

// ADD data (transaction use karke)
function addOrder(order) {
  const db = getDB();
  const tx = db.transaction("orders", "readwrite");
  const store = tx.objectStore("orders");
  store.add(order);
}

// GET data by key
function getOrder(id) {
  const db = getDB();
  const tx = db.transaction("orders", "readonly");
  const store = tx.objectStore("orders");
  const request = store.get(id);
  
  request.onsuccess = () => console.log("Order:", request.result);
}

// INDEX se query
function getOrdersByStatus(status) {
  const db = getDB();
  const tx = db.transaction("orders", "readonly");
  const store = tx.objectStore("orders");
  const index = store.index("status");
  const request = index.getAll(status);
  
  request.onsuccess = () => {
    console.log(`"${status}" orders:`, request.result);
  };
}

// DELETE data
function deleteOrder(id) {
  const db = getDB();
  const tx = db.transaction("orders", "readwrite");
  tx.objectStore("orders").delete(id);
}

// Example data
addOrder({
  itemName: "Mutton Biryani",
  qty: 2,
  price: 900,
  status: "pending",
  date: new Date().toISOString()
});