slowmode: fix bot slowmodes not being applied for slowmodes over 6h; add -mode option; add eager permission checks

backend/src/plugins/Slowmode/commands/SlowmodeSetCmd.ts

@@ -0,0 +1,154 @@
+import { commandTypeHelpers as ct } from "../../../commandTypes";
+import { slowmodeCmd } from "../types";
+import { TextChannel } from "eris";
+import humanizeDuration from "humanize-duration";
+import { sendErrorMessage, sendSuccessMessage } from "src/pluginUtils";
+import { asSingleLine, DAYS, disableInlineCode, HOURS, MINUTES } from "src/utils";
+import { disableBotSlowmodeForChannel } from "../util/disableBotSlowmodeForChannel";
+import { actualDisableSlowmodeCmd } from "../util/actualDisableSlowmodeCmd";
+import { getMissingPermissions } from "../../../utils/getMissingPermissions";
+import { missingPermissionError } from "../../../utils/missingPermissionError";
+import { BOT_SLOWMODE_PERMISSIONS, NATIVE_SLOWMODE_PERMISSIONS } from "../requiredPermissions";
+
+const MAX_NATIVE_SLOWMODE = 6 * HOURS; // 6 hours
+const MAX_BOT_SLOWMODE = DAYS * 365 * 100; // 100 years
+const MIN_BOT_SLOWMODE = 15 * MINUTES;
+
+const validModes = ["bot", "native"];
+type TMode = "bot" | "native";
+
+export const SlowmodeSetCmd = slowmodeCmd({
+  trigger: "slowmode",
+  permission: "can_manage",
+  source: "guild",
+
+  // prettier-ignore
+  signature: [
+    {
+      time: ct.delay(),
+
+      mode: ct.string({ option: true, shortcut: "m" }),
+    },
+    {
+      channel: ct.textChannel(),
+      time: ct.delay(),
+
+      mode: ct.string({ option: true, shortcut: "m" }),
+    }
+  ],
+
+  async run({ message: msg, args, pluginData }) {
+    const channel: TextChannel = args.channel || msg.channel;
+
+    if (args.time === 0) {
+      // Workaround until we can call SlowmodeDisableCmd from here
+      return actualDisableSlowmodeCmd(msg, { channel }, pluginData);
+    }
+
+    const defaultMode: TMode =
+      pluginData.config.getForChannel(channel).use_native_slowmode && args.time <= MAX_NATIVE_SLOWMODE
+        ? "native"
+        : "bot";
+
+    const mode = (args.mode as TMode) || defaultMode;
+    if (!validModes.includes(mode)) {
+      sendErrorMessage(pluginData, msg.channel, "--mode must be 'bot' or 'native'");
+      return;
+    }
+
+    // Validate durations
+    if (mode === "native" && args.time > MAX_NATIVE_SLOWMODE) {
+      sendErrorMessage(pluginData, msg.channel, "Native slowmode can only be set to 6h or less");
+      return;
+    }
+
+    if (mode === "bot" && args.time > MAX_BOT_SLOWMODE) {
+      sendErrorMessage(
+        pluginData,
+        msg.channel,
+        `Sorry, bot managed slowmodes can be at most 100 years long. Maybe 99 would be enough?`,
+      );
+      return;
+    }
+
+    if (mode === "bot" && args.time < MIN_BOT_SLOWMODE) {
+      sendErrorMessage(
+        pluginData,
+        msg.channel,
+        asSingleLine(`
+          Bot managed slowmode must be 15min or more.
+          Use \`--mode native\` to use native slowmodes for short slowmodes instead.
+        `),
+      );
+      return;
+    }
+
+    // Verify permissions
+    const channelPermissions = channel.permissionsOf(pluginData.client.user.id);
+
+    if (mode === "native") {
+      const missingPermissions = getMissingPermissions(channelPermissions, NATIVE_SLOWMODE_PERMISSIONS);
+      if (missingPermissions) {
+        sendErrorMessage(
+          pluginData,
+          msg.channel,
+          `Unable to set native slowmode. ${missingPermissionError(missingPermissions)}`,
+        );
+        return;
+      }
+    }
+
+    if (mode === "bot") {
+      const missingPermissions = getMissingPermissions(channelPermissions, BOT_SLOWMODE_PERMISSIONS);
+      if (missingPermissions) {
+        sendErrorMessage(
+          pluginData,
+          msg.channel,
+          `Unable to set bot managed slowmode. ${missingPermissionError(missingPermissions)}`,
+        );
+        return;
+      }
+    }
+
+    // Apply the slowmode!
+    const rateLimitSeconds = Math.ceil(args.time / 1000);
+
+    if (mode === "native") {
+      // If there is an existing bot-maintained slowmode, disable that first
+      const existingBotSlowmode = await pluginData.state.slowmodes.getChannelSlowmode(channel.id);
+      if (existingBotSlowmode) {
+        await disableBotSlowmodeForChannel(pluginData, channel);
+      }
+
+      // Set native slowmode
+      try {
+        await channel.edit({
+          rateLimitPerUser: rateLimitSeconds,
+        });
+      } catch (e) {
+        return sendErrorMessage(
+          pluginData,
+          msg.channel,
+          `Failed to set native slowmode: ${disableInlineCode(e.message)}`,
+        );
+      }
+    } else {
+      // If there is an existing native slowmode, disable that first
+      if (channel.rateLimitPerUser) {
+        await channel.edit({
+          rateLimitPerUser: 0,
+        });
+      }
+
+      await pluginData.state.slowmodes.setChannelSlowmode(channel.id, rateLimitSeconds);
+    }
+
+    const humanizedSlowmodeTime = humanizeDuration(args.time);
+    const slowmodeType = mode === "native" ? "native slowmode" : "bot-maintained slowmode";
+    sendSuccessMessage(
+      pluginData,
+      msg.channel,
+      `Set ${humanizedSlowmodeTime} slowmode for <#${channel.id}> (${slowmodeType})`,
+    );
+  },
+});