import { Type } from "@sinclair/typebox";
import type { ExtensionAPI } from "../_shared/pi-api.js";
import { textResult } from "../_shared/pi-api.js";
import { validateParams } from "../_shared/validation.js";

const HelloParams = Type.Object({
  name: Type.String({ description: "Who to greet", minLength: 1, maxLength: 100 }),
  language: Type.Optional(Type.Union([Type.Literal("en"), Type.Literal("ru")], { default: "en", description: "Greeting language" })),
});

export default function helloTool(pi: ExtensionAPI): void {
  pi.registerTool({
    name: "helloTool",
    description: "Deterministic TypeBox-backed example tool.",
    parameters: HelloParams,
    execute(_toolCallId, params) {
      const valid = validateParams(HelloParams, params);
      if (!valid.ok) return valid.result;
      const greeting = valid.value.language === "ru" ? `Привет, ${valid.value.name}!` : `Hello, ${valid.value.name}!`;
      return textResult(greeting, { greeting, language: valid.value.language ?? "en" });
    },
  });
}