add captcha

client/captcha.js

@@ -0,0 +1,52 @@
+/* https://raw.githubusercontent.com/napa3um/node-captcha/refs/heads/master/captcha.js */
+
+import Route from "../route.js";
+import initDb from "../db.js";
+import Canvas from "canvas";
+import crypto from "node:crypto";
+
+let db = await initDb();
+
+// TODO: rewrite
+let main = new Route([], async function (req, res, input) {
+    const canvas = new Canvas.Canvas(250, 100)
+    const ctx = canvas.getContext('2d')
+
+    ctx.antialias = 'gray'
+    ctx.fillStyle = 'black'
+    ctx.fillRect(0, 0, 250, 100)
+    ctx.fillStyle = 'red'
+    ctx.lineWidth = 3
+    ctx.strokeStyle = 'red'
+    ctx.font = `40px sans`
+
+    // draw two curve lines:
+    for (var i = 0; i < 2; i++) {
+        ctx.moveTo(Math.floor(0.08 * 250), Math.random() * 100)
+        ctx.bezierCurveTo(Math.floor(0.32 * 250), Math.random() * 100, Math.floor(1.07 * 100), Math.random() * 100, Math.floor(0.92 * 250), Math.random() * 100)
+        ctx.stroke()
+    }
+
+    // draw text:
+    const text = ('' + crypto.randomBytes(4).readUIntBE(0, 4)).substring(2, 10)
+    text.split('').forEach((char, i) => {
+        ctx.setTransform(Math.random() * 0.5 + 1, Math.random() * 0.4, Math.random() * 0.4, Math.random() * 0.5 + 1, Math.floor(0.375 * 50) * i + Math.floor(0.25 * 10), Math.floor(1.25 * 40))
+        ctx.fillText(char, 0, 0)
+    })
+
+    let ck = crypto.randomUUID();
+
+    res.cookie('captcha', ck);
+    await db.run('INSERT INTO captcha (key, solution) VALUES (?,?)', [
+        ck,
+        text
+    ])
+
+    // send image:
+    res.type('jpg')
+    res.header('Cache-Control', 'no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0')
+    res.header('Expires', 'Sun, 19 May 1984 02:00:00 GMT')
+    canvas.jpegStream().pipe(res)
+});
+
+export default main;