address_book.py

"""
**************************************
 ADDRESS BOOK (LEGACY / MESSY VERSION)
 Works, but badly designed
**************************************
"""

contacts = []
last_id = 0


def add_contact(name, phone, email, address):
    global last_id

    if name is None or name == "":
        print("Name is required")
        return False

    if phone is None or phone == "":
        print("Phone is required")
        return False

    for c in contacts:
        if c["phone"] == phone:
            print("Phone already exists")
            return False

    last_id = last_id + 1

    contact = {
        "id": last_id,
        "name": name,
        "phone": phone,
        "email": email if email else "",
        "address": address if address else "",
        "created_at": __import__("datetime").datetime.now().isoformat()
    }

    contacts.append(contact)
    print("Contact added:", contact["name"])
    return True


def get_all_contacts():
    if len(contacts) == 0:
        print("No contacts found")
        return []

    result = []
    for c in contacts:
        result.append(c)

    return result


def find_contact_by_phone(phone):
    if not phone:
        print("Phone required")
        return None

    for c in contacts:
        if c["phone"] == phone:
            return c

    return None


def update_contact(phone, new_name, new_email, new_address):
    found = False

    for c in contacts:
        if c["phone"] == phone:
            if new_name:
                c["name"] = new_name

            if new_email:
                c["email"] = new_email

            if new_address:
                c["address"] = new_address

            c["updated_at"] = __import__("datetime").datetime.now().isoformat()
            print("Contact updated")
            found = True

    if not found:
        print("Contact not found")
        return False

    return True


def delete_contact(phone):
    index = -1

    for i in range(len(contacts)):
        if contacts[i]["phone"] == phone:
            index = i

    if index == -1:
        print("Contact not found")
        return False

    contacts.pop(index)
    print("Contact deleted")
    return True


def search_contacts(keyword):
    results = []

    if not keyword:
        return results

    for c in contacts:
        if (
            keyword in c["name"]
            or keyword in c["phone"]
            or keyword in c["email"]
        ):
            results.append(c)

    return results


# -------------------
# Demo usage
# -------------------

add_contact("John Doe", "0700000001", "john@email.com", "Kampala")
add_contact("Jane Smith", "0700000002", "", "")
update_contact("0700000001", "John D.", None, "Ntinda")

print(get_all_contacts())

addressBook.js

/**************************************
 * ADDRESS BOOK (LEGACY / MESSY VERSION)
 **************************************/

let contacts = [];
let lastId = 0;

function addContact(name, phone, email, address) {
    if (name == null || name === "") {
        console.log("Name is required");
        return false;
    }

    if (phone == null || phone === "") {
        console.log("Phone is required");
        return false;
    }

    for (let i = 0; i < contacts.length; i++) {
        if (contacts[i].phone === phone) {
            console.log("Phone already exists");
            return false;
        }
    }

    lastId = lastId + 1;

    let contact = {
        id: lastId,
        name: name,
        phone: phone,
        email: email ? email : "",
        address: address ? address : "",
        createdAt: new Date().toISOString()
    };

    contacts.push(contact);
    console.log("Contact added:", contact.name);
    return true;
}

function getAllContacts() {
    if (contacts.length === 0) {
        console.log("No contacts found");
        return [];
    }

    let result = [];
    for (let i = 0; i < contacts.length; i++) {
        result.push(contacts[i]);
    }
    return result;
}

function findContactByPhone(phone) {
    if (!phone) {
        console.log("Phone required");
        return null;
    }

    for (let i = 0; i < contacts.length; i++) {
        if (contacts[i].phone === phone) {
            return contacts[i];
        }
    }

    return null;
}

function updateContact(phone, newName, newEmail, newAddress) {
    let found = false;

    for (let i = 0; i < contacts.length; i++) {
        if (contacts[i].phone === phone) {
            if (newName) {
                contacts[i].name = newName;
            }

            if (newEmail) {
                contacts[i].email = newEmail;
            }

            if (newAddress) {
                contacts[i].address = newAddress;
            }

            contacts[i].updatedAt = new Date().toISOString();
            console.log("Contact updated");
            found = true;
        }
    }

    if (!found) {
        console.log("Contact not found");
        return false;
    }

    return true;
}

function deleteContact(phone) {
    let index = -1;

    for (let i = 0; i < contacts.length; i++) {
        if (contacts[i].phone === phone) {
            index = i;
        }
    }

    if (index === -1) {
        console.log("Contact not found");
        return false;
    }

    contacts.splice(index, 1);
    console.log("Contact deleted");
    return true;
}

function searchContacts(keyword) {
    let results = [];

    if (!keyword) {
        return results;
    }

    for (let i = 0; i < contacts.length; i++) {
        if (
            contacts[i].name.includes(keyword) ||
            contacts[i].phone.includes(keyword) ||
            contacts[i].email.includes(keyword)
        ) {
            results.push(contacts[i]);
        }
    }

    return results;
}

/*************
 * Demo usage
 *************/

addContact('John Doe', '0700000001', 'john@email.com', 'Kampala');
addContact("Jane Smith", "0700000002", "", "");
updateContact("0700000001", "John D.", null, "Ntinda");

console.log(getAllContacts());
console.log(findContactByPhone("0700000002"));
console.log(searchContacts("John"));

module.exports = {
    addContact,
    getAllContacts,
    findContactByPhone,
    updateContact,
    deleteContact,
    searchContacts
}