Combine Knub's type helpers with Zeppelin's, continue Utility plugin port

backend/src/plugins/Utility/commands/HelpCmd.ts

@@ -0,0 +1,91 @@
+import { utilityCmd } from "../types";
+import { commandTypeHelpers as ct } from "../../../commandTypes";
+import { createChunkedMessage, messageLink } from "../../../utils";
+import { sendErrorMessage } from "../../../pluginUtils";
+import { TextChannel } from "eris";
+import { ZeppelinPlugin } from "../../ZeppelinPlugin";
+import { PluginCommandDefinition } from "knub/dist/commands/commandUtils";
+import { LoadedPlugin } from "knub";
+
+export const HelpCmd = utilityCmd({
+  trigger: "help",
+  description: "Show a quick reference for the specified command's usage",
+  usage: "!help clean",
+  permission: "can_help",
+
+  signature: {
+    command: ct.string({ catchAll: true }),
+  },
+
+  async run({ message: msg, args, pluginData }) {
+    const searchStr = args.command.toLowerCase();
+
+    const matchingCommands: Array<{
+      plugin: LoadedPlugin;
+      command: PluginCommandDefinition;
+    }> = [];
+
+    const guildData = pluginData.getKnubInstance().getLoadedGuild(pluginData.guild.id);
+    for (const plugin of guildData.loadedPlugins.values()) {
+      const registeredCommands = plugin.pluginData.commands.getAll();
+      for (const registeredCommand of registeredCommands) {
+        for (const trigger of registeredCommand.originalTriggers) {
+          const strTrigger = typeof trigger === "string" ? trigger : trigger.source;
+
+          if (strTrigger.startsWith(searchStr)) {
+            matchingCommands.push({
+              plugin,
+              command: registeredCommand,
+            });
+          }
+        }
+      }
+    }
+
+    const totalResults = matchingCommands.length;
+    const limitedResults = matchingCommands.slice(0, 3);
+    const commandSnippets = limitedResults.map(({ plugin, command }) => {
+      const prefix: string = command.originalPrefix
+        ? typeof command.originalPrefix === "string"
+          ? command.originalPrefix
+          : command.originalPrefix.source
+        : "";
+
+      const originalTrigger = command.originalTriggers[0];
+      const trigger: string = originalTrigger
+        ? typeof originalTrigger === "string"
+          ? originalTrigger
+          : originalTrigger.source
+        : "";
+
+      const description = command.config.extra.blueprint.description;
+      const usage = command.config.extra.blueprint.usage;
+      const commandSlug = trigger
+        .trim()
+        .toLowerCase()
+        .replace(/\s/g, "-");
+
+      const pluginName = plugin.blueprint?.name || plugin.class?.pluginName;
+
+      let snippet = `**${prefix}${trigger}**`;
+      if (description) snippet += `\n${description}`;
+      if (usage) snippet += `\nBasic usage: \`${usage}\``;
+      snippet += `\n<https://zeppelin.gg/docs/plugins/${pluginName}/usage#command-${commandSlug}>`;
+
+      return snippet;
+    });
+
+    if (totalResults === 0) {
+      msg.channel.createMessage("No matching commands found!");
+      return;
+    }
+
+    let message =
+      totalResults !== limitedResults.length
+        ? `Results (${totalResults} total, showing first ${limitedResults.length}):\n\n`
+        : "";
+
+    message += `${commandSnippets.join("\n\n")}`;
+    createChunkedMessage(msg.channel, message);
+  },
+});