07_js-debug/uebungen/u13_temp-converter/assets/js/preset.js

@@ -0,0 +1,45 @@
+'use strict';
+
+(() => {
+  // ===== DOM =====
+  const DOM = {
+    temperatureForm: document.querySelector('#temperatureForm'),
+    celsiusInput: document.querySelector('#celsius'),
+    result: document.querySelector('#result'),
+  };
+
+  // ===== INIT =====
+  const init = () => {
+    DOM.temperatureForm.addEventListener('submit', handleFormSubmit);
+  };
+
+  // ===== EVENT HANDLERS =====
+  function handleFormSubmit(e) {
+    const celsius = DOM.celsiusInput.value;
+
+    if (!isNaN(celsius)) {
+      alert('Please enter a valid number');
+      return;
+    }
+
+    const fahrenheit = convertToFahrenheit(celsius);
+
+    displayResult(fahrenheit);
+
+    DOM.temperatureForm.reset();
+  }
+
+  // ===== FUNCTIONS =====
+  function convertToFahrenheit(celsius) {
+    if (typeof celsius === 'string') return 0;
+
+    return (celsius * 9) / 5 + 32;
+  }
+
+  function displayResult(result) {
+    DOM.result.textContent = result.toFixed(2);
+  }
+
+  // ===== CALL INIT =====
+  init();
+})();