Added interactable terminal

frontend/src/components/Navbar.tsx

@@ -2,6 +2,7 @@ import Image from 'next/image';
 import Link from 'next/link';
 import { useEffect, useState } from 'react';
 import Hamburger from './Hamburger';
+import Terminal from './Terminal';
 
 const Navbar = () => {
   const [path, setPath] = useState<string[]>([]);
@@ -13,22 +14,25 @@ const Navbar = () => {
 
   return (
     <nav className="sticky top-0 flex justify-between items-center relative z-10 shadow-lg rounded-md bg-black/15 backdrop-blur-md xl:px-24 md:px-10 px-5 py-6">
-      <Link href="/">
-        <Image
-          src="/assets/csesoc_logo.svg"
-          alt="CSESoc Logo"
-          width={200}
-          height={200}
-          draggable={false}
-        />
+      <div>
+        <Link href="/">
+          <Image
+            src="/assets/csesoc_logo.svg"
+            alt="CSESoc Logo"
+            width={200}
+            height={200}
+            draggable={false}
+          />
+        </Link>
         <p className="font-mono mt-3 font-bold">
           <span className="text-green-500">csesoc@unsw</span>
           <span>:</span>
           <span className="text-blue-500">~{path.map(segment => '/' + segment.toLowerCase())}</span>
           <span>$ </span>
-          <span id="cursor" className="text-gray-400 inline-block animate-blink">_</span>
+          {/* The interactive terminal that allows changing pages using 'cd' */}
+          <Terminal/>
         </p>
-      </Link>
+      </div>
       <div>
         <div className="md:flex xl:gap-18 lg:gap-10 md:gap-5 text-right font-bold hidden">
           <Link href="/about">

frontend/src/components/Terminal.tsx

@@ -0,0 +1,100 @@
+import { useRouter } from "next/router";
+import { useRef, useState } from "react";
+
+const Terminal = () => {
+  // Store the value of the input
+  const [value, setValue] = useState("");
+
+  // Automatically select the end of the input as the custom
+  // cursor only works at the end of the input.
+  const inputRef = useRef<HTMLInputElement>(null);
+  const setInputEnd = () => {
+    if (inputRef.current) {
+      const len = inputRef.current.value.length;
+      inputRef.current.setSelectionRange(len, len);
+    }
+  }
+
+  // Keep track of if the input is focused
+  const [inputFocused, setInputFocused] = useState(false);
+
+  // Using the router to change pages seamlessly
+  const router = useRouter();
+  const goToPage = (target: string) => {
+    router.push(target);
+  };
+
+  // Checking for "Enter" and if so, changing to
+  // the inputted page
+  const handleKey = (key: string) => {
+    if (key !== "Enter") return;
+
+    if (value.toLowerCase() === "~"
+      || value.toLowerCase() === "cd"
+      || value.toLowerCase() === "cd ~"
+      || value.toLowerCase() === "cd .."
+    ) {
+      goToPage("/");
+    } else if (value.toLowerCase() === "cd about"
+      || value.toLowerCase() === "cd about us"
+      || value.toLowerCase() === "cd about_us"
+    ) {
+      goToPage("/about");
+    } else if (value.toLowerCase() === "cd events"
+      || value.toLowerCase() === "cd event"
+    ) {
+      goToPage("/events");
+    } else if (value.toLowerCase() === "cd resources"
+      || value.toLowerCase() === "cd resource"
+    ) {
+      goToPage("/resources");
+    } else if (value.toLowerCase() === "cd sponsors"
+      || value.toLowerCase() === "cd sponsor"
+    ) {
+      goToPage("/sponsors");
+    } else if (value.toLowerCase() === "cd contact"
+      || value.toLowerCase() === "cd contacts"
+      || value.toLowerCase() === "cd contact us"
+      || value.toLowerCase() === "cd contact_us"
+    ) {
+      goToPage("/contact-us");
+    }
+
+    clearInput()
+  };
+
+  const clearInput = () => {
+    setValue("");
+  };
+
+  return (
+    // Using relative + absolute to overlap the `input` and `span`
+    <span className="relative">
+      {/* The input */}
+      <input type="text" id="input" value={value} ref={inputRef} maxLength={40}
+        className="absolute text-blue-500 p-0 m-0 bg-transparent outline-none caret-transparent w-[50vw] z-10"
+        onKeyDown={(e) => {
+          handleKey(e.key)
+          setInputEnd()
+        }}
+        onChange={(e) => setValue(e.target.value)}
+        onFocus={() => setInputFocused(true)}
+        onBlur={() => {
+          clearInput()
+          setInputFocused(false)
+        }}
+      ></input>
+      {/* The custom cursor */}
+      <span className="absolute w-[60vw] p-0 m-0 z-0">
+        {/* The invisable span that is the same length as the input */}
+        <span
+          className="invisible whitespace-pre pointer-events-none text-base"
+        >{value}</span>
+        {/* The custom cursor */}
+        <span id="cursor" className={`text-${inputFocused ? "white" : "gray-500"} pointer-events-none inline-block animate-blink p-0 m-0`}>_</span>
+      </span>
+    </span>
+  )
+}
+
+export default Terminal