Better bots

README.md

@@ -112,7 +112,7 @@ You can debug this application by adding the following configuration to your `la
   "cwd": "${workspaceFolder}",
   "runtimeExecutable": "npm",
   "runtimeArgs": [
-      "run", "start-debug"
+    "run", "start-debug"
   ],
   "port": 1338
 }

backend/player/bot.js

@@ -1,4 +1,70 @@
-const {sample, pull, times} = require("lodash");
+const { sample, pull, times, shuffle } = require("lodash");
+const pileSort = require("pile-sort");
+
+const RARITY_ORDER = ["Mythic", "Rare", "Uncommon", "Common", "Basic"];
+function sortByRarity (cards) {
+  return shuffle(cards).sort((a, b) => {
+    return RARITY_ORDER.indexOf(a.rarity) - RARITY_ORDER.indexOf(b.rarity);
+  });
+}
+
+const decidingPicksNumber = 6;
+function samplePick (pack, pool, myColors) {
+  if (pool.length === decidingPicksNumber) {
+    const colorCount = pool.reduce(
+      (acc, pack) => {
+        pack.colorIdentity.forEach(color => { acc[color] += 1; });
+        return acc;
+      },
+      {
+        W: 0,
+        U: 0,
+        B: 0,
+        R: 0,
+        G: 0
+        // TODO count colourless?
+      }
+    );
+
+    const countColors = Object.keys(colorCount).reduce(
+      (acc, color) => {
+        const count = colorCount[color];
+        if (!acc[count]) {
+          acc[count] = [];
+        }
+        acc[count].push(color);
+        return acc;
+      },
+      {}
+    );
+    const orderedColors = Object.values(countColors)
+      .reduce(
+        (acc, next) => {
+          return [...acc, ...shuffle(next)];
+        },
+        []
+      );
+
+    myColors.clear();
+    orderedColors.slice(0, 2).forEach(color => myColors.add(color));
+  }
+
+  const [cardsInMyColors, cardsNotInMyColors] = pileSort(pack, [
+    card => {
+      return (
+        card.colorIdentity.length === 0 ||
+        card.colorIdentity.some(color => myColors.has(color))
+        // NOTE: this means if you if your colors are WU, you can find your bot
+        // picks a WG card (they match on W and are splashing?)
+      );
+    }
+  ]);
+
+  const orderedPicks = sortByRarity(cardsInMyColors);
+  if (orderedPicks.length) return orderedPicks[0];
+
+  return sortByRarity(cardsNotInMyColors)[0];
+}
 
 const Player = require("./index");
 const logger = require("../logger");
@@ -14,15 +80,18 @@ module.exports = class Bot extends Player {
     this.gameId= gameId;
     this.picksPerPack = picksPerPack;
     this.burnsPerPack = burnsPerPack;
+
+    this.myColors = new Set(["W", "U", "B", "R", "G"]); // bot chooses 2 colors at some point
   }
 
   getPack(pack) {
     const cardsToPick = Math.min(this.picksPerPack, pack.length);
     times(cardsToPick, () => {
-      const randomPick = sample(pack);
-      logger.info(`GameID: ${this.gameId}, Bot, picked: ${randomPick.name}`);
-      this.picks.push(randomPick.name);
-      pull(pack, randomPick);
+      const card = samplePick(pack, this.pool, this.myColors);
+      logger.info(`GameID: ${this.gameId}, Bot, picked: ${card.name}`);
+      this.pool.push(card);
+      this.picks.push(card.name);
+      pull(pack, card);
     });
 
     // burn cards

backend/player/index.js

@@ -24,11 +24,11 @@ class Player extends EventEmitter {
         picks: [],
         burns: []
       },
-      pool: [],
+      pool: [], // cards you have picks from packs
+      picks: [], // string names of picked cards
       cap: {
         packs: {}
       },
-      picks: [],
       draftLog: {
         round : {},
         pack: []

package.json

@@ -74,6 +74,7 @@
     "jsonfile": "^6.1.0",
     "lodash": "^4.17.21",
     "node-schedule": "^2.1.1",
+    "pile-sort": "^1.0.2",
     "prop-types": "^15.8.1",
     "react": "^17.0.2",
     "react-dom": "^17.0.2",