add roll command

src/commands/roll.ts

@@ -0,0 +1,107 @@
+import axios from "axios";
+
+interface RollResult {
+  distance: number;
+  id: string;
+  title: string;
+}
+
+const url = `https://backend-map.vault48.org/api/route/random`;
+const successMessages = [
+  "Вот маршрут для тебя: {link}, {dist}км",
+  "Ну вот есть, например, {link}, всего {dist}км",
+  "Нашёл {link}, всего {dist}км, надо ехать",
+  "Вот, {link}, всего {dist}км, катал его, нет?",
+];
+
+const failureMessages = [
+  "Ничего не нашёл 🤷",
+  "Не, такого нет, попробуй снова",
+  "Может, что-то и было такое, но сейчас я не ничего не нашёл.",
+];
+
+const say = (vals: string[]) =>
+  vals[Math.floor(Math.random() * (vals.length - 1))];
+
+const parseVal = (val?: string) => {
+  const parsed = val && parseInt(val, 10);
+
+  if (!parsed || !Number.isFinite(parsed) || parsed <= 0 || parsed >= 10000) {
+    return;
+  }
+
+  return parsed;
+};
+
+const escape = (val?: string) => val && val.replace(/([-.\[\]])/g, "\\$1");
+const deviate = (max: number, factor: number) => [
+  Math.round(max * (1 - factor)),
+  Math.round(max * (1 + factor)),
+];
+
+// begin search in range of 80%-120% of specified distance
+const startDeviation = 0.2;
+// add 10% each time we haven't found anything
+const deviationStep = 0.1;
+// perform this amount of tries, increasing deviation each time we haven't found anything
+const deviationTries = 8;
+
+const getRoute = async (
+  min?: number,
+  max?: number
+): Promise<RollResult | undefined> => {
+  if (!min && !max) {
+    return axios.get<RollResult>(url).then((it) => it.data);
+  }
+
+  if (min && max && min > max) {
+    return axios
+      .get<RollResult>(url, { params: { min: max, max: min } })
+      .then((it) => it.data);
+  }
+
+  if (min && max) {
+    return axios
+      .get<RollResult>(url, { params: { min, max } })
+      .then((it) => it.data);
+  }
+
+  if (!min) {
+    return;
+  }
+
+  for (let i = 0; i < deviationTries; i += 1) {
+    const deviation = startDeviation + deviationStep * i;
+
+    let [devMin, devMax] = deviate(min, deviation);
+
+    try {
+      return await axios
+        .get<RollResult>(url, { params: { min: devMin, max: devMax } })
+        .then((it) => it.data)
+        .catch();
+    } catch (error) {}
+  }
+};
+
+export const roll = async (text: string) => {
+  try {
+    const parts = text.trim().split(" ");
+
+    const result = await getRoute(parseVal(parts[1]), parseVal(parts[2]));
+
+    if (!result || !result?.id) {
+      return say(failureMessages);
+    }
+
+    const link = `https://map.vault48.org/${result.id}`;
+    const distance = result.distance.toFixed(0);
+    const message = say(successMessages);
+
+    return message
+      .replace("{dist}", distance)
+      .replace("{link}", `[${escape(result.title ?? link)}](${escape(link)})`);
+  } catch (error) {
+    console.warn("Error, when trying to fetch random route", error);
+  }
+};

src/index.ts

@@ -6,6 +6,7 @@ import { TelegramApi } from "./api/telegram";
 import { HttpApi } from "./api/http";
 import { PostgresDB } from "./service/db/postgres";
 import { PgTransport } from "./service/db/postgres/loggerTransport";
+import { roll } from "./commands/roll";
 
 async function main() {
   try {
@@ -29,9 +30,11 @@ async function main() {
     await httpApi.listen();
     await telegramApi.probe();
 
+    telegram.hears(/\/roll(.*)/, roll);
+
     logger.info("bot successfully started");
   } catch (e) {
-    logger.error(`FATAL EXCEPTION ${e.message}`);
+    logger.error(`FATAL EXCEPTION ${e}`);
   }
 }
 

src/service/telegram/index.ts

@@ -8,6 +8,8 @@ import { ExtraReplyMessage } from "telegraf/typings/telegram-types";
 
 // import SocksProxyAgent from 'socks-proxy-agent';
 
+const maxMessageAge = 3 * 60e3; // skip messages older than this seconds
+
 export class TelegramService {
   public readonly bot: Telegraf;
   public readonly webhook: WebhookConfig = {};
@@ -18,7 +20,7 @@ export class TelegramService {
       telegram: {
         webhookReply: true,
         apiMode: "bot",
-        // agent, // TODO: add proxy support
+        // agent, // TODO: add proxy support if they block it
       },
     };
 
@@ -158,4 +160,40 @@ export class TelegramService {
       !!username && !!this.props.owners && this.props.owners.includes(username)
     );
   };
+
+  public hears = (
+    what: string | RegExp,
+    callback: (
+      text: string
+    ) => string | Promise<string | undefined> | undefined | void
+  ) =>
+    this.bot.hears(what, async (ctx) => {
+      let text: string | void | undefined = "%% not received %%";
+
+      try {
+        const age = Date.now() - ctx.message.date * 1000;
+        const message = ctx.update.message.text;
+
+        if (age > maxMessageAge) {
+          console.warn(
+            `skipped message "${message}", since its age ${age / 1000} seconds`
+          );
+
+          return;
+        }
+
+        text = await callback(message);
+
+        if (!text) {
+          return;
+        }
+
+        ctx.reply(text, { parse_mode: "MarkdownV2" });
+      } catch (error) {
+        console.warn(
+          `error replying to ${what} (${ctx.update.message.text}) with message "${text}"`,
+          error
+        );
+      }
+    });
 }