main.js: rework dynamic captcha rendering to correctly reset when a user posts

templates/main.js

@@ -255,6 +255,20 @@ function getCaptchaPubKey() {
 {% endif %}
 }
 
+// Should be called by the captcha API when it's ready. Ugly I know... D:
+window.onCaptchaLoadTurnstile = function() {
+	// Do not actually pass any parameters, as those should already be included in the HTML node.
+	let widgetId = turnstile.render('captcha-container', {});
+	if (widgetId === undefined) {
+		console.error('Could not render Turnstile captcha!');
+		return;
+	}
+	document.addEventListener('post', function(e) {
+		// User posted! Reset the captcha.
+		turnstile.reset(widgetId);
+	});
+}
+
 function initDynamicCaptcha() {
 	if (isDynamicCaptchaEnabled()) {
 		let pub_key = getCaptchaPubKey();
@@ -317,6 +331,7 @@ function dopost(form) {
 	saved[document.location] = form.elements['body'].value;
 	sessionStorage.body = JSON.stringify(saved);
 
+	document.dispatchEvent(new Event('post'));
 	return form.elements['body'].value != "" || (form.elements['file'] && form.elements['file'].value != "") || (form.elements.file_url && form.elements['file_url'].value != "");
 }
 

templates/post_form.html

@@ -117,7 +117,7 @@
 				{{ antibot.html() }}
 			</th>
 			<td>
-				<div class="cf-turnstile" data-sitekey="{{ config.turnstile_public }}" data-action="{{ form_action_type }}"></div>
+				<div class="captcha-container" data-sitekey="{{ config.turnstile_public }}" data-action="{{ form_action_type }}"></div>
 				{{ antibot.html() }}
 			</td>
 		</tr>