feat: handle github lines urls and send content

src/commands/github.ts

@@ -0,0 +1,6 @@
+import { defineCommand } from "../loaders/commands.ts";
+
+defineCommand({
+  name: "github",
+  description: "Search on github"
+})

src/listeners/message_create.ts

@@ -1,14 +1,19 @@
-import { Events, Message } from "discord.js";
+import { ActionRowBuilder, ButtonBuilder, ButtonStyle, Events, Message } from "discord.js";
 import { defineListener } from "../loaders/listeners.ts";
 import { MESSAGE_PREFIX } from "../constants.ts";
 import { COMMANDS } from "../loaders/commands.ts";
 import { MessageCommandContext } from "../structs/context/CommandContext.ts";
+import { extname } from "node:path"; 
+import { safeSlice } from "../util.ts";
+
+const GITHUB_LINE_URL_REGEX = /^(?:https?:\/\/)?(?:www\.)?(?:github)\.com\/(?<repo>[a-zA-Z0-9-_]+\/[A-Za-z0-9_.-]+)\/blob\/(?<path>.+?)#L(?<first_line_number>\d+)[-~]?L?(?<second_line_number>\d*)/i;
 
 defineListener({
   event: Events.MessageCreate,
   run: async(message: Message) => {
-    if (!message.content.toLowerCase().startsWith(MESSAGE_PREFIX))
-      return;
+    if (message.system || message.author.bot) return;
+
+    if (!message.content.toLowerCase().startsWith(MESSAGE_PREFIX)) return handleOthers(message);
 
     const [commandName, ...args] = message.content
       .slice(MESSAGE_PREFIX.length)
@@ -30,3 +35,56 @@ defineListener({
       });
   }
 });
+
+function handleOthers(message: Message) {
+  handleGithubLink(message);
+}
+
+async function handleGithubLink(message: Message) {
+  const match = GITHUB_LINE_URL_REGEX.exec(message.content);
+  const groups = match?.groups;
+  if (!groups) return;
+
+  const repo = groups.repo;
+  const path = groups.path;
+  const extension = extname(path).slice(1);
+  const firstLineNumber = parseInt(groups.first_line_number) - 1;
+  const secondLineNumber = parseInt(groups.second_line_number) || firstLineNumber + 1;
+
+  // limit, max 25 lines - possible flood
+  if (secondLineNumber - firstLineNumber > 25) {
+    message.react("❌");
+    return;
+  }
+
+  const contentUrl = `https://raw.githubusercontent.com/${repo}/${path}`;
+  const response = await fetch(contentUrl);
+  const content = await response.text();
+  const lines = content.split("\n");
+
+  let text = "";
+
+  for (let i = 0; i < lines.length; i++) {
+    if (i < firstLineNumber || i >= secondLineNumber) continue;
+
+    const line = lines[i];
+    text += `${line}\n`;
+  }
+
+  // delete the last \n
+  text = text.slice(0, -1);
+
+  message.reply({
+    content: `\`\`\`${extension}\n${safeSlice(text, 2000 - 6 - extension.length)}\n\`\`\``,
+    components: [
+      new ActionRowBuilder<ButtonBuilder>()
+        .setComponents(
+          new ButtonBuilder()
+            .setLabel(repo)
+            .setStyle(ButtonStyle.Link)
+            .setURL(`https://github.com/${repo}`)
+        )
+        .toJSON()
+    ]
+  })
+}

src/util.ts

@@ -1,5 +1,5 @@
-export function safeSlice<T>(array: T[], length: number) {
-  return array.length > length ? array.slice(0, length) : array;
+export function safeSlice<T>(input: T[] | string, length: number) {
+  return input.length > length ? input.slice(0, length) : input;
 }
 
 export async function silently<T>(value: Promise<T>) {