LONDON | MAY 2025 | JESUS DEL MORAL | DATA FLOWS | BOOK LIBRARY

debugging/book-library/script.js

@@ -1,3 +1,5 @@
+
+
 let myLibrary = [];
 
 window.addEventListener("load", function (e) {
@@ -7,16 +9,15 @@ window.addEventListener("load", function (e) {
 
 function populateStorage() {
   if (myLibrary.length == 0) {
-    let book1 = new Book("Robison Crusoe", "Daniel Defoe", "252", true);
+    let book1 = new Book("Robison Crusoe", "Daniel Defoe", 252, true);
     let book2 = new Book(
       "The Old Man and the Sea",
       "Ernest Hemingway",
-      "127",
+      127,
       true
     );
     myLibrary.push(book1);
     myLibrary.push(book2);
-    render();
   }
 }
 
@@ -28,17 +29,19 @@ const check = document.getElementById("check");
 //check the right input from forms and if its ok -> add the new book (object in array)
 //via Book function and start render function
 function submit() {
-  if (
-    title.value == null ||
-    title.value == "" ||
-    pages.value == null ||
-    pages.value == ""
-  ) {
-    alert("Please fill all fields!");
+  const cleanTitle = title.value.trim();
+  const cleanAuthor = author.value.trim();
+  const cleanPages = parseInt(pages.value, 10);
+
+  if (!cleanTitle|| !cleanAuthor) {  // title and author doesn't allowed to contain only space characters
+    alert("Title and Author cannot be empty or spaces only."); 
+    return false;
+  } else if (isNaN(cleanPages) || cleanPages <= 0) {   // the value of type of pages must be a integer 
+    alert("Pages must be a positive whole number.");
     return false;
   } else {
-    let book = new Book(title.value, title.value, pages.value, check.checked);
-    library.push(book);
+    let book = new Book(cleanTitle, cleanAuthor, pages.value, check.checked);  //// title and author be allowed to contain leading or trailing space characters, we storage using parseInt
+    myLibrary.push(book);
     render();
   }
 }
@@ -52,11 +55,10 @@ function Book(title, author, pages, check) {
 
 function render() {
   let table = document.getElementById("display");
-  let rowsNumber = table.rows.length;
   //delete old table
-  for (let n = rowsNumber - 1; n > 0; n-- {
-    table.deleteRow(n);
-  }
+  // Keep only the header row
+  table.innerHTML = table.rows[0].outerHTML;
+
   //insert updated row and cells
   let length = myLibrary.length;
   for (let i = 0; i < length; i++) {
@@ -66,37 +68,35 @@ function render() {
     let pagesCell = row.insertCell(2);
     let wasReadCell = row.insertCell(3);
     let deleteCell = row.insertCell(4);
-    titleCell.innerHTML = myLibrary[i].title;
-    authorCell.innerHTML = myLibrary[i].author;
-    pagesCell.innerHTML = myLibrary[i].pages;
+    titleCell.textContent = myLibrary[i].title;
+    authorCell.textContent = myLibrary[i].author;
+    pagesCell.textContent = myLibrary[i].pages;
 
     //add and wait for action for read/unread button
-    let changeBut = document.createElement("button");
-    changeBut.id = i;
-    changeBut.className = "btn btn-success";
-    wasReadCell.appendChild(changeBut);
+    let toggleReadButton = document.createElement("button");
+    toggleReadButton.className = "btn btn-success";
+    wasReadCell.appendChild(toggleReadButton);
     let readStatus = "";
-    if (myLibrary[i].check == false) {
-      readStatus = "Yes";
-    } else {
-      readStatus = "No";
-    }
-    changeBut.innerText = readStatus;
 
-    changeBut.addEventListener("click", function () {
+    readStatus = myLibrary[i].check ? "Yes" : "No";
+
+    toggleReadButton.innerText = readStatus;
+
+    toggleReadButton.addEventListener("click", function () {
       myLibrary[i].check = !myLibrary[i].check;
       render();
     });
+
 
     //add delete button to every row and render again
-    let delButton = document.createElement("button");
-    delBut.id = i + 5;
-    deleteCell.appendChild(delBut);
-    delBut.className = "btn btn-warning";
-    delBut.innerHTML = "Delete";
-    delBut.addEventListener("clicks", function () {
-      alert(`You've deleted title: ${myLibrary[i].title}`);
-      myLibrary.splice(i, 1);
+    let deleteBookButton = document.createElement("button");
+    deleteCell.appendChild(deleteBookButton);
+    deleteBookButton.className = "btn btn-warning";
+    deleteBookButton.innerHTML = "Delete";
+    deleteBookButton.addEventListener("click", function () {
+      const deleteTitle = myLibrary[i].title; //store first 
+      myLibrary.splice(i, 1);                 // delete it 
+      alert(`You have deleted title: ${deleteTitle}`);
       render();
     });
   }