/**
* Class for managing user data in local storage.
*/
class UserDataAccess {
///////////////////////////////////////////////
// PRIVATE INSTANCE VARIABLES (start with #)
///////////////////////////////////////////////
/**
* Dummy user data to populate the local storage database.
* @type {Array<Object>}
* @private
*/
#dummyData = [
{ id: 1, firstName: "Jane", lastName: "Doe", email: "jdoe@acme.com" },
{ id: 2, firstName: "Tony", lastName: "Thompsom", email: "tony@acme.com" },
{ id: 3, firstName: "Jesse", lastName: "Jones", email: "jesse@acme.com" }
];
//////////////////////////////////
// CONSTRUCTOR
//////////////////////////////////
/**
* Initializes the UserDataAccess instance.
* Ensures that local storage has the 'userData' key populated with dummy data if not already set.
*/
constructor() {
if (!localStorage.getItem("userData")) {
localStorage.setItem("userData", JSON.stringify(this.#dummyData));
}
}
//////////////////////////////////
// PUBLIC METHODS
//////////////////////////////////
/**
* Retrieves all users from local storage.
* @returns {Array<Object>} Array of user objects.
*/
getAllUsers() {
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
return users;
}
/**
* Retrieves a user by their ID.
* @param {number} id - The ID of the user to retrieve.
* @returns {Object|null} The user object or null if not found.
*/
getUserById(id) {
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
return users.find((u) => u.id == id) || null;
}
/**
* Inserts a new user into the local storage database.
* @param {Object} newUser - The new user object to insert.
*/
insertUser(newUser) {
newUser.id = this.#getMaxId() + 1;
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
users.push(newUser);
localStorage.setItem("userData", JSON.stringify(users));
}
/**
* Updates an existing user in the local storage database.
* @param {Object} updatedUser - The user object with updated data.
*/
updateUser(updatedUser) {
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
const indexOfUserToUpdate = users.findIndex(u => updatedUser.id == u.id);
if (indexOfUserToUpdate !== -1) {
users[indexOfUserToUpdate] = updatedUser;
localStorage.setItem("userData", JSON.stringify(users));
}
}
/**
* Deletes a user by their ID from the local storage database.
* @param {number} id - The ID of the user to delete.
*/
deleteUser(id) {
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
const indexOfUserToRemove = users.findIndex(u => id == u.id);
if (indexOfUserToRemove !== -1) {
users.splice(indexOfUserToRemove, 1);
localStorage.setItem("userData", JSON.stringify(users));
}
}
//////////////////////////////////
// PRIVATE METHODS (start with #)
//////////////////////////////////
/**
* Retrieves the maximum user ID from the current database.
* @returns {number} The highest user ID.
* @private
*/
#getMaxId() {
const str = localStorage.getItem("userData");
const users = JSON.parse(str);
return users.reduce((maxId, user) => Math.max(maxId, user.id), 0);
}
}