// postgres's tools — postgres's own code (novox/hq ADR 0039), importing postgres's own client. They
// return structured data; the mesh serves them through the sdk's tool harness. Both call through
// PostgresClient.query(), the module's one pending execution boundary (see client.ts): the tool
// shapes are fixed and correct, and surface the TODO honestly until that boundary is backed.

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

export function getPostgresTools(postgres: PostgresClient): ToolDefinition[] {
  return [
    {
      name: "postgres_list_databases",
      description: "List the databases on the postgres server, with their on-disk size.",
      input: {},
      run: async () => ({ databases: await postgres.listDatabases() }),
    },
    {
      name: "postgres_query",
      description: "Run a read-only SQL query against a named database (wrapped in a read-only transaction).",
      input: {
        database: { type: "string", description: "the database to query" },
        sql: { type: "string", description: "the SELECT (or other read-only) statement" },
      },
      run: async (args) => {
        const database = String(args.database ?? "");
        const sql = String(args.sql ?? "");
        if (!database) throw new Error("postgres_query: database is required");
        if (!sql) throw new Error("postgres_query: sql is required");
        const result = await postgres.readOnlyQuery(database, sql);
        return { database, command: result.command, rows: result.rows };
      },
    },
  ];
}

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