Moved files from src/htmlcards to iwmlib.

lib/card/theme.js

@@ -0,0 +1,46 @@
+/* eslint-disable no-unused-vars */
+
+/**
+ * The Theme class helps manage the card themes.
+ * Usually it overrides or enhances aspects of the card.js.
+ *
+ * @class Theme
+ */
+class Theme {
+
+    /**
+     * Loads a config file and parses it to JSON.
+     *
+     * @static
+     * @param {string} [path=null] - Optional: A path where the config file is located at (including the filename and extension).
+     * @returns {Promise} - Returns a promise, that returns the parsed json file when resolved.
+     * @memberof Theme
+     */
+    static loadConfig(path = null) {
+        return new Promise((resolve, reject) => {
+            path = (path) ? path : './config.json'
+
+            let xhttp = new XMLHttpRequest()
+            xhttp.onreadystatechange = function () {
+                if (this.readyState == 4) {
+
+                    if (this.status == 200 || Theme._isLocal()) {
+                        try {
+                            const json = JSON.parse(this.responseText)
+                            resolve(json)
+
+                        } catch (e) {
+                            reject(e)
+                        }
+                    } else reject('Invalid request : ' + this.status)
+                }
+            }
+            xhttp.open('GET', path, true)
+            xhttp.send()
+        })
+    }
+
+    static _isLocal() {
+        return (window.location.protocol == 'file:')
+    }
+}