// mongodb's tools — mongodb's own code (novox/hq ADR 0044), importing mongodb's own client. They
// return structured data; the mesh serves them through the sdk's tool harness. Both call through
// MongoClient.evalJs(), the module's one execution boundary (see client.ts).

import { registerModuleTools, type ToolDefinition } from "@novox/mesh-sdk/tools";
import { MongoClient } from "../client.js";

export function getMongoTools(mongo: MongoClient): ToolDefinition[] {
  return [
    {
      name: "mongodb_list_databases",
      description: "List the databases on the mongodb server, with their on-disk size.",
      input: {},
      run: async () => ({ databases: await mongo.listDatabases() }),
    },
    {
      name: "mongodb_query",
      description: "Run a read-only find against a collection in a named database and return the matching documents.",
      input: {
        database: { type: "string", description: "the database to query" },
        collection: { type: "string", description: "the collection to read from" },
        filter: { type: "object", description: "the MongoDB query filter (defaults to {} — all documents)" },
        limit: { type: "number", description: "maximum documents to return (default 100, capped at 1000)" },
      },
      run: async (args) => {
        const database = String(args.database ?? "");
        const collection = String(args.collection ?? "");
        if (!database) throw new Error("mongodb_query: database is required");
        if (!collection) throw new Error("mongodb_query: collection is required");
        const filter = isObject(args.filter) ? args.filter : {};
        const limit = Number(args.limit ?? 100) || 100;
        const documents = await mongo.find(database, collection, filter, limit);
        return { database, collection, documents };
      },
    },
  ];
}

function isObject(v: unknown): v is Record<string, unknown> {
  return typeof v === "object" && v !== null && !Array.isArray(v);
}

// The tools exist only when the server can be reached from the environment; without it, mongodb
// contributes none rather than failing the whole tool runtime.
registerModuleTools("mongodb", (env) => {
  try {
    return getMongoTools(MongoClient.fromEnv(env));
  } catch {
    return [];
  }
});