Add script.js

script.js

@@ -0,0 +1,162 @@
+// ==UserScript==
+// @name         mathtrainer.ai auto solve
+// @namespace    http://tampermonkey.net/
+// @version      1
+// @description  :p
+// @author       elias
+// @match        https://mathtrainer.ai/*
+// @grant        none
+// ==/UserScript==
+
+// made by elias @ 15 sep. 2025
+
+(function() {
+    'use strict';
+
+    let lastExpression = '';
+    let isProcessing = false;
+    let InputEvents = {};
+
+    function hook(element) {
+        element.addEventListener = new Proxy(element.addEventListener, {
+            apply(target, _this, args) {
+                const [type, listener] = args;
+                if (_this.tagName === 'SECTION' && _this.classList.contains('answer')) {
+                    InputEvents[type] = listener;
+                }
+                return target.apply(_this, args);
+            }
+        });
+    }
+    hook(HTMLElement.prototype);
+
+    function keypress(target, key) {
+        const event = new KeyboardEvent('keydown', {
+            key: key,
+            code: key.length === 1 ? `Digit${key}` : (key === 'Enter' ? 'Enter' : 'Unknown'),
+            bubbles: true,
+            cancelable: true
+        });
+
+        if (InputEvents.keydown) {
+            InputEvents.keydown({
+                target: target,
+                key: key,
+                type: 'keydown',
+                preventDefault: () => {},
+                stopPropagation: () => {}
+            });
+        }
+
+        target.dispatchEvent(event);
+    }
+
+    function evaluateMath(expression) {
+        if (!expression) return null;
+        expression = expression
+            .replace(/\\times/g, '*')
+            .replace(/×/g, '*')
+            .replace(/÷/g, '/')
+            .replace(/−/g, '-')
+            .replace(/\\div/g, '/')
+            .replace(/\\sqrt\{(\d+)\}/g, 'Math.sqrt($1)')
+            .replace(/\\sqrt\[(\d+)\]\{(\d+)\}/g, 'Math.pow($2, 1/$1)')
+            .replace(/\^/g, '**')
+            .replace(/\s+/g, '');
+        try {
+            const result = Function('"use strict"; return (' + expression + ')')();
+            if (Number.isFinite(result)) {
+                if (Math.abs(result - Math.round(result)) < 1e-10) {
+                    return Math.round(result); // round near-integers (39.99999.. -> 40)
+                } 
+                return result;
+            }
+            return null;
+        } catch (e) {
+            return null;
+        }
+    }
+
+    function randomDelay(min, max) {
+        return Math.floor(Math.random() * (max - min + 1)) + min;
+    }
+
+    async function inputAnswer(answerSection, result) {
+        const resultStr = String(result);
+
+        await new Promise(resolve => setTimeout(resolve, randomDelay(300, 500)));
+
+        for (let i = 0; i < resultStr.length; i++) {
+            keypress(answerSection, resultStr[i]);
+
+            if (i < resultStr.length - 1) {
+                await new Promise(resolve => setTimeout(resolve, randomDelay(300, 500)));
+            }
+        }
+
+        await new Promise(resolve => setTimeout(resolve, randomDelay(300, 500)));
+    }
+
+    async function processQuestion() {
+        if (isProcessing) return;
+        isProcessing = true;
+
+        try {
+            const annotation = document.querySelector('annotation[encoding="application/x-tex"]');
+            if (!annotation) {
+                isProcessing = false;
+                return;
+            }
+
+            const expression = annotation.textContent.trim();
+            if (!expression || expression === lastExpression) {
+                isProcessing = false;
+                return;
+            }
+
+            lastExpression = expression;
+
+            const result = evaluateMath(expression);
+            if (result === null) {
+                isProcessing = false;
+                return;
+            }
+
+            // console.log("Detected:", expression);
+            // console.log("Answer:", result);
+
+            const answerSection = document.querySelector('section.answer');
+            if (!answerSection) {
+                isProcessing = false;
+                return;
+            }
+
+            await inputAnswer(answerSection, result);
+
+            // keypress(answerSection, 'Enter');
+            // not needed as it gets auto-entered
+            isProcessing = false;
+
+        } catch (e) {
+            isProcessing = false;
+        }
+    }
+
+    const observer = new MutationObserver(() => {
+        processQuestion();
+    });
+
+    observer.observe(document.body, {
+        childList: true,
+        subtree: true,
+        attributes: true
+    });
+
+    // sometimes observer doesnt catch it :(
+    // use interval loop as fallback
+    setInterval(() => {
+        if (!isProcessing) {
+            processQuestion();
+        }
+    }, 500);
+})();