Mini Project: Contact Book App

import json

class ContactBook:
    def __init__(self):
        self.contacts = {}
    
    def add(self, name, phone, email=""):
        self.contacts[name.title()] = {
            "phone": phone,
            "email": email
        }
        print(f"  Added: {name.title()}")
    
    def search(self, query):
        query = query.lower()
        results = {k: v for k, v in self.contacts.items()
                   if query in k.lower() or query in v["phone"]}
        return results
    
    def display_all(self):
        if not self.contacts:
            print("  No contacts found.")
            return
        print("\n  === Contact Book ===")
        for name, info in sorted(self.contacts.items()):
            print(f"  {name}")
            print(f"    Phone: {info['phone']}")
            if info['email']:
                print(f"    Email: {info['email']}")
    
    def to_json(self):
        return json.dumps(self.contacts, indent=2)

# Demo
book = ContactBook()
book.add("Alice Smith", "9876543210", "alice@email.com")
book.add("Bob Jones", "8765432109", "bob@email.com")
book.add("Charlie Brown", "7654321098")
book.add("Alice Wang", "6543210987", "awang@email.com")

book.display_all()

# Search
print("\n  Search 'alice':")
results = book.search("alice")
for name, info in results.items():
    print(f"    {name}: {info['phone']}")

# Export as JSON
print("\n  === JSON Export ===")
print(book.to_json())