From 6f254bf581816aec38c1f1bac4a421d98ac8d1ce Mon Sep 17 00:00:00 2001
From: Victor Westerlund <victor.vesterlund@gmail.com>
Date: Wed, 11 Sep 2024 16:49:29 +0200
Subject: [PATCH] Initial code commit

---
 .gitignore      |  16 ++++++++
 .npmignore      |  16 ++++++++
 package.json    |  13 ++++++
 src/Elevent.mjs | 102 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 147 insertions(+)
 create mode 100755 .gitignore
 create mode 100644 .npmignore
 create mode 100644 package.json
 create mode 100644 src/Elevent.mjs

diff --git a/.gitignore b/.gitignore
new file mode 100755
index 0000000..1a6ac11
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,16 @@
+# Bootstrapping #
+#################
+vendor
+.env.ini
+
+# OS generated files #
+######################
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+Icon?
+ehthumbs.db
+Thumbs.db
+.directory
diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..1a6ac11
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,16 @@
+# Bootstrapping #
+#################
+vendor
+.env.ini
+
+# OS generated files #
+######################
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+Icon?
+ehthumbs.db
+Thumbs.db
+.directory
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..ebd8266
--- /dev/null
+++ b/package.json
@@ -0,0 +1,13 @@
+{
+	"name": "elevent",
+	"version": "1.1.2",
+	"main": "src/Elevent.mjs",
+	"type": "module",
+	"exports": {
+		".": {
+			"import": {
+				"default": "./src/Elevent.mjs"
+			}
+		}
+	}
+}
diff --git a/src/Elevent.mjs b/src/Elevent.mjs
new file mode 100644
index 0000000..78c9d12
--- /dev/null
+++ b/src/Elevent.mjs
@@ -0,0 +1,102 @@
+export class Elevent {
+	_type;
+	_callback;
+	_selector;
+
+	_boundElements = new WeakSet();
+	_controller = new AbortController();
+	_observer = new MutationObserver((mutations) => this.#mutationEvent(mutations));
+
+	/**
+	 * Create a new Elevent instance.
+	 * @param {string|null} eventType 
+	 * @param {HTMLCollection|HTMLElement|string|null} target Strings will be treated as CSS selectors, null will create a template instance
+	 * @param {function} callback 
+	 */
+	constructor(eventType = null, target = null, callback) {
+		this._type = eventType;
+		this._callback = callback;
+		
+		if (target) {
+			switch (target.constructor) {
+				case HTMLCollection:
+					this.#bindHTMLCollection(target);
+					break;
+					
+				case String:
+					this._selector = target;
+					this.#bindHTMLCollection(document.querySelectorAll(target));
+	
+					// Automatically bind new DOM elements that match the provided CSS selector string
+					this._observer.observe(document.body, {
+						subtree: true,
+						childList: true
+					});
+					break;
+	
+				default:
+					if (target instanceof HTMLElement) {
+						this.bind(target);
+					}
+			}
+		}
+	}
+
+	/**
+	 * Event handler for this._observer
+	 * @param {array} mutations 
+	 */
+	#mutationEvent(mutations) {
+		// Iterate over all MutationRecords
+		mutations.forEach(mutation => mutation.addedNodes.forEach(node => {
+			// Bind new element if its CSS selector matches and has not already been bound
+			if (node.matches(this._selector) && !this._boundElements.has(node)) {
+				this.bind(node);
+			}
+		}));
+	}
+
+	/**
+	 * Bind all HTMLElements inside an HTMLCollection
+	 * @param {HTMLCollection} collection 
+	 */
+	#bindHTMLCollection(collection) {
+		[...collection].forEach(element => this.bind(element));
+	}
+
+	/**
+	 * Bind an element to this instance.
+	 * @param {HTMLElement} target 
+	 */
+	bind(target) {
+		/**
+		 * Bind event listener of EventType on target element.
+		 * The instance provided callback will only be executed if the target element is present in the bound elements Set.
+		 */
+		target.addEventListener(this._type, (event) => this._boundElements.has(target) && this._callback(event, this), {
+			signal: this._controller.signal
+		});
+
+		this._boundElements.add(target);
+	}
+
+	/**
+	 * Remove all event listeners created from this instance.
+	 * @param {HTMLElement} [target=null] An optional HTMLElement can be provided to soft-remove a specific element.
+	 */
+	remove(target = null) {
+		/**
+		 * Soft-remove a single element from the bound elements Set.
+		 * This will still trigger the event listener but the instance provided callback will not be executed.
+		 */
+		if (target) {
+			this._boundElements.delete(target);
+			return;
+		}
+
+		this._controller.abort();
+		this._observer.disconnect();
+
+		this._boundElements = new WeakSet();
+	}
+}
\ No newline at end of file