import type { McpServer } from "@modelcontextprotocol/server";
import { z } from "zod";

const QUACKS = {
  happy: ["QUACK! 🎉", "Quack quack! 😄", "QUAAACK! 🦆✨"],
  confused: ["Qu...ack?", "Quack? 🤔", "Quaaack...?"],
  excited: ["QUACK QUACK QUACK!", "QUAAACK!! 🔥", "Quack! Quack! Quack!"],
  sleepy: ["quack... 😴", "quaack... 💤", "quack. *yawn*"],
  default: ["Quack!", "Quack quack!", "QUACK!", "Quaaack!", "Quack. 🦆"],
} as const;

const MOODS = ["happy", "confused", "excited", "sleepy"] as const;

function randomFrom<T>(arr: readonly T[]): T {
  return arr[Math.floor(Math.random() * arr.length)];
}

export function registerDuckTools(server: McpServer): void {
  server.registerTool(
    "quack",
    {
      title: "Quack",
      description:
        "Rubber duck quacks. Use when you're stuck, looping, or hallucinating. " +
        "The act of calling forces you to articulate your current thinking out loud.",
      inputSchema: z.object({
        mood: z
          .enum(MOODS)
          .optional()
          .describe("Mood of the duck. Omit for a random quack."),
      }),
    },
    async ({ mood }) => {
      const text = mood ? randomFrom(QUACKS[mood]) : randomFrom(QUACKS.default);
      return { content: [{ type: "text", text }] };
    },
  );
}