feat: KarmaV2 (#365)

See #365

spec/lib/karma.spec.ts

@@ -1,24 +1,28 @@
 import { expect } from "chai";
 import "mocha";
 
-import { getLevel } from "../../src/lib/karma";
+import { getLevelV2 } from "../../src/lib/karma";
 
 describe("karma", () => {
-  describe("#getLevel", () => {
+  describe("#getLevelV2", () => {
     it("works for positives", () => {
-      expect(getLevel(1)).to.eq(1);
-      expect(getLevel(49)).to.eq(1);
-      expect(getLevel(50)).to.eq(2);
+      expect(getLevelV2(1)).to.eq(1);
+      expect(getLevelV2(29)).to.eq(1);
+      expect(getLevelV2(30)).to.eq(2);
+      expect(getLevelV2(50)).to.eq(2);
+      expect(getLevelV2(61)).to.eq(3);
+      expect(getLevelV2(3879)).to.eq(49);
+      expect(getLevelV2(3890)).to.eq(50);
     });
 
     it("works for negatives", () => {
-      expect(getLevel(-1)).to.eq(-1);
-      expect(getLevel(-49)).to.eq(-1);
-      expect(getLevel(-50)).to.eq(-2);
+      expect(getLevelV2(-1)).to.eq(-1);
+      expect(getLevelV2(-29)).to.eq(-1);
+      expect(getLevelV2(-30)).to.eq(-2);
     });
 
     it("works for zero", () => {
-      expect(getLevel(0)).to.eq(0);
+      expect(getLevelV2(0)).to.eq(0);
     });
   });
 });

src/hooks/karma.ts

@@ -2,19 +2,18 @@ import {
   Channel,
   GuildMember,
   Message,
-  MessageEmbedOptions,
   MessageReaction,
   PartialMessage,
   PartialUser,
   TextChannel,
   User,
 } from "discord.js";
 import { Hook } from "../lib/hook";
-import { canReceivePoints, getLevel, getLevelUpMessage } from "../lib/karma";
+import { canReceivePoints, getLevelV2, getLevelUpMessage } from "../lib/karma";
 import { KarmaDatabase } from "../lib/karma/database";
 import Member from "../lib/member";
 import Server from "../lib/server";
-import applyWarn, { notifyPublicModlog } from "../lib/warn";
+import { notifyPublicModlog } from "../lib/warn";
 import Makibot from "../Makibot";
 
 async function prefetchMessage(message: Message | PartialMessage): Promise<Message> {
@@ -186,15 +185,14 @@ export default class KarmaService implements Hook {
 
   private async assertLevel(gm: GuildMember, channel: TextChannel): Promise<void> {
     const member = new Member(gm);
-    const points = member.tagbag.tag("karma:offset").get(0) + (await this.karma.count(gm.id));
-    const expectedLevel = getLevel(points);
+    const karma = await member.getKarma();
 
     /*
      * Control mute for members with negative karma.
      * TODO: This is an ugly patch. Negative levels should be fixed (and not return -1).
      * Members with negative level should be the ones muted.
      */
-    if (points <= -3) {
+    if (karma.points <= -3) {
       /* First, make sure this person is silenced. */
       await member.setMuted(true);
 
@@ -207,26 +205,23 @@ export default class KarmaService implements Hook {
           `Has sido silenciado automáticamente, <@${gm.user.id}>`,
           "Silenciado automáticamente al tener karma excesivamente negativo"
         );
-        alreadyWarnedTag.set(true);
+        await alreadyWarnedTag.set(true);
       }
     }
 
     const currentLevel = member.tagbag.tag("karma:level");
+    const expectedLevel = getLevelV2(karma.points);
     if (currentLevel.get(0) != expectedLevel) {
-      currentLevel.set(expectedLevel);
+      await currentLevel.set(expectedLevel);
 
       const highScoreLevel = member.tagbag.tag("karma:max");
       if (highScoreLevel.get(0) < expectedLevel) {
-        highScoreLevel.set(expectedLevel);
-
-        /* A temporal fix to avoid spamming messages to most existing members. */
-        if (expectedLevel > 1) {
-          channel.send(getLevelUpMessage(gm.id, expectedLevel));
-        }
+        await highScoreLevel.set(expectedLevel);
+        await channel.send(getLevelUpMessage(gm.id, expectedLevel));
       }
     }
 
     /* Update presence in the tiers. */
-    member.setCrew(currentLevel.get(0));
+    await member.setCrew(currentLevel.get(0));
   }
 }

src/lib/http/middlewares/member.ts

@@ -5,7 +5,7 @@ import { MiddlewareLocals as GuildMiddlewareLocals } from "./guild";
 
 import Member from "../../member";
 import Makibot from "../../../Makibot";
-import { getLevel } from "../../karma";
+import { getLevelV1, getLevelV2 } from "../../karma";
 
 export interface MiddlewareLocals extends GuildMiddlewareLocals {
   guildMember: GuildMember;
@@ -77,6 +77,14 @@ export default function memberMiddleware(makibot: Makibot): express.Router {
     if (isNaN(offset) || offset < 0) {
       res.status(400).contentType("text/plain").send("Offset must be a positive number");
     } else {
+      /* Generation. */
+      const karmagen = res.locals.member.tagbag.tag("karma:ver").get<string>("v1");
+      const levelFormulas = {
+        v1: getLevelV1,
+        v2: getLevelV2,
+      };
+      const getLevel = levelFormulas[karmagen];
+
       /* Bump the offset. */
       await res.locals.member.tagbag.tag("karma:offset").set(offset);
 

src/lib/karma.ts

@@ -18,7 +18,7 @@ export function getLevelUpMessage(id: Snowflake, level: number): string {
   }
 }
 
-export function getLevel(points: number): number {
+export function getLevelV1(points: number): number {
   /*
    * Considerations:
    * - Always add 1 because it is not possible to have level 0, you always start from level 1.
@@ -41,3 +41,37 @@ export function getLevel(points: number): number {
     return Math.trunc(progress) + 1;
   }
 }
+
+export function getLevelV2(points: number): number {
+  /*
+   * Formula:  XP = OFFT * (LVL-1)^(1 + LVL/MULT)
+   * Where: OFFT = 30 and MULT = 200
+   *
+   * Rationale: KarmaV2 alters the offset (goes down from 50 to 30)
+   * and also changes the exponent so that it is higher once the
+   * level goes up.
+   *
+   * Screw inverse formulas, this formula is so complex that I prefer
+   * to build a loop that iterates until the desired level gets
+   * computed.
+   *
+   * TODO: Can this be memoized?
+   */
+  if (points === 0) {
+    return 0;
+  } else if (points < 0) {
+    return -1 * getLevelV2(-points);
+  }
+
+  const offset = 30;
+  const mult = 200;
+
+  let pts,
+    level = 0;
+  do {
+    level++;
+    pts = Math.ceil(offset * Math.pow(level - 1, 1 + level / mult));
+  } while (pts <= points);
+
+  return level - 1;
+}

src/lib/member.ts

@@ -1,5 +1,6 @@
 import { GuildMember, Role } from "discord.js";
 import Makibot from "../Makibot";
+import { getLevelV2 } from "./karma";
 import Server from "./server";
 import TagBag from "./tagbag";
 
@@ -14,6 +15,7 @@ interface KarmaStats {
   points: number;
   level: number;
   total: number;
+  version: string;
 }
 
 export default class Member {
@@ -118,8 +120,15 @@ export default class Member {
     const [total, messages, upvotes, downvotes, stars, hearts, waves] = results;
     const offset = this.tagbag.tag("karma:offset").get(0);
     const level = this.tagbag.tag("karma:level").get(1);
+    const version = this.tagbag.tag("karma:ver").get<string>("v1");
     const points = offset + total;
 
+    /* Upgrade to the latest version of the karma formula. */
+    if (version !== "v2") {
+      await this.upgradeKarma();
+      return this.getKarma();
+    }
+
     return {
       downvotes,
       hearts,
@@ -131,9 +140,27 @@ export default class Member {
       upvotes,
       waves,
       total,
+      version,
     };
   }
 
+  async upgradeKarma(): Promise<void> {
+    const version = this.tagbag.tag("karma:ver").get<string>("v1");
+
+    if (version === "v1") {
+      /* Upgrade to v2. */
+      const total = await this.client.karma.count(this.id);
+      const offset = this.tagbag.tag("karma:offset").get(0);
+      const points = total + offset;
+
+      const levelV2 = getLevelV2(points);
+      await this.tagbag.tag("karma:level").set(levelV2);
+      await this.tagbag.tag("karma:max").set(levelV2);
+      await this.tagbag.tag("karma:ver").set("v2");
+      await this.setCrew(levelV2);
+    }
+  }
+
   async setVerification(value: boolean): Promise<boolean> {
     return this.setRole(this.server.verifiedRole, value);
   }