Initial commit: Freebee Matrix community bot

Full-featured Matrix bot with E2EE via matrix-js-sdk, 32+ plugins,
LLM-powered passive classification, XP/leveling, trivia, game releases,
anime/movie tracking, and more.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/plugins/tools.ts

@@ -0,0 +1,84 @@
+import { IMatrixClient, Plugin, CommandDef, MessageContext } from "./base";
+import { evaluate } from "mathjs";
+import QRCode from "qrcode";
+import logger from "../utils/logger";
+
+export class ToolsPlugin extends Plugin {
+  constructor(client: IMatrixClient) {
+    super(client);
+  }
+
+  get name() {
+    return "tools";
+  }
+
+  get commands(): CommandDef[] {
+    return [
+      { name: "calc", description: "Inline calculator", usage: "!calc <expression>" },
+      { name: "qr", description: "Generate a QR code image", usage: "!qr <text or URL>" },
+    ];
+  }
+
+  async onMessage(ctx: MessageContext): Promise<void> {
+    if (this.isCommand(ctx.body, "calc")) {
+      await this.handleCalc(ctx);
+    } else if (this.isCommand(ctx.body, "qr")) {
+      await this.handleQr(ctx);
+    }
+  }
+
+  private async handleCalc(ctx: MessageContext): Promise<void> {
+    const expr = this.getArgs(ctx.body, "calc");
+    if (!expr) {
+      await this.sendReply(ctx.roomId, ctx.eventId, "Usage: !calc <expression>");
+      return;
+    }
+
+    // Normalize natural language patterns
+    let normalized = expr
+      .replace(/(\d),(\d)/g, "$1$2") // strip thousands commas: 450,000 -> 450000
+      .replace(/(\d+(?:\.\d+)?)\s*%\s*of\s*(\d+(?:\.\d+)?)/gi, "($1 / 100) * $2")
+      .replace(/(\d+(?:\.\d+)?)\s*%/g, "($1 / 100)");
+
+    try {
+      const result = evaluate(normalized);
+      const display = typeof result === "number"
+        ? Number.isInteger(result) ? result.toLocaleString("en-US") : parseFloat(result.toFixed(10)).toLocaleString("en-US")
+        : String(result);
+      await this.sendReply(ctx.roomId, ctx.eventId, `${expr} = ${display}`);
+    } catch (err) {
+      await this.sendReply(ctx.roomId, ctx.eventId, `Could not evaluate: ${expr}`);
+    }
+  }
+
+  private async handleQr(ctx: MessageContext): Promise<void> {
+    const text = this.getArgs(ctx.body, "qr");
+    if (!text) {
+      await this.sendReply(ctx.roomId, ctx.eventId, "Usage: !qr <text or URL>");
+      return;
+    }
+
+    try {
+      const pngBuffer = await QRCode.toBuffer(text, { type: "png", width: 300, margin: 2 });
+      const mxcUrl = await this.client.uploadContent(pngBuffer, "image/png", "qrcode.png");
+
+      await this.client.sendMessage(ctx.roomId, {
+        msgtype: "m.image",
+        body: "qrcode.png",
+        url: mxcUrl,
+        info: {
+          mimetype: "image/png",
+          w: 300,
+          h: 300,
+          size: pngBuffer.length,
+        },
+        "m.relates_to": {
+          "m.in_reply_to": { event_id: ctx.eventId },
+        },
+      });
+    } catch (err) {
+      logger.error(`QR generation failed: ${err}`);
+      await this.sendReply(ctx.roomId, ctx.eventId, "Failed to generate QR code.");
+    }
+  }
+}