import { describe, expect, it } from "vitest";
import { query } from "./clickhouse.js";
import { NeedMoreData, Cursor } from "../src/readers/core.js";
import { readPoint } from "../src/readers/geo.js";

async function reader(expr: string): Promise<Cursor> {
  return new Cursor(await query(`SELECT ${expr} FORMAT RowBinary`));
}

describe("readPoint", () => {
  it("decodes a Point as [x, y]", async () => {
    const r = await reader("CAST((1.5, 2.5) AS Point)");
    expect(readPoint(r)).toEqual([1.5, 2.5]);
    expect(r.pos).toBe(16); // two Float64
  });

  describe("advance() edge cases", () => {
    it("throws NeedMoreData for every incomplete prefix (0 .. full.length-1)", async () => {
      const full = await query(
        "SELECT CAST((1.5, 2.5) AS Point) FORMAT RowBinary",
      );
      for (let len = 0; len < full.length; len++) {
        const r = new Cursor(full.subarray(0, len));
        let thrown: unknown;
        try {
          readPoint(r);
        } catch (e) {
          thrown = e;
        }
        expect(thrown, `prefix length ${len} of ${full.length}`).toBe(
          NeedMoreData,
        );
      }
    });
  });
});