trx-rs/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/aprs-symbols.test.mjs

// SPDX-FileCopyrightText: 2026 Stan Grams <sjg@haxx.space>
//
// SPDX-License-Identifier: GPL-2.0-or-later

import assert from "node:assert/strict";
import test from "node:test";
import vm from "node:vm";
import { readFile } from "node:fs/promises";
import { bundleEntry } from "./bundle-entry.mjs";

const sharedUrl = new URL("../src/plugins/aprs-shared.ts", import.meta.url);
const stylePath = new URL("../../assets/web/style.css", import.meta.url);

async function loadShared() {
  const source = await bundleEntry(sharedUrl, "trxAprsShared");
  const context = vm.createContext({ Math, String, Number, Array, Date, Set, console });
  new vm.Script(source).runInContext(context);
  return context.trxAprsShared;
}

// The sheets are 16x6 grids of 24px cells covering 0x21..0x7E, so cell index
// is `code - 0x21`.  Getting this wrong shifts every station to a neighbouring
// icon, which is invisible in a screenshot but wrong on every packet.
test("sprite cells are indexed from the first printable symbol code", async () => {
  const { aprsSymbolSprite } = await loadShared();

  const first = aprsSymbolSprite("/", "!");
  assert.equal(first.className, "aprs-symbol-primary");
  assert.equal(first.backgroundPosition, "0px 0px");
  assert.equal(first.label, "Primary APRS symbol /!");
  // '>' is 0x3E -> index 29 -> column 13, row 1.
  assert.equal(aprsSymbolSprite("/", ">").backgroundPosition, "-312px -24px");
  // '~' is 0x7E -> index 93 -> the last cell of the last row.
  assert.equal(aprsSymbolSprite("/", "~").backgroundPosition, "-312px -120px");
});

test("the table identifier selects the primary, alternate, or overlay sheet", async () => {
  const { aprsSymbolSprite } = await loadShared();

  assert.equal(aprsSymbolSprite("/", "_").className, "aprs-symbol-primary");
  assert.equal(aprsSymbolSprite("\\", "_").className, "aprs-symbol-alternate");

  // An alphanumeric table identifier is an overlay character drawn on top of
  // the alternate symbol: overlay cell first, then the symbol cell.
  const overlaid = aprsSymbolSprite("S", ">");
  assert.equal(overlaid.className, "aprs-symbol-overlaid");
  assert.equal(overlaid.backgroundPosition, "-48px -72px, -312px -24px");
  assert.equal(overlaid.label, "Alternate APRS symbol \\> with overlay S");
});

test("codes outside the sprite sheets fall back to the raw character", async () => {
  const { aprsSymbolSprite, renderLocalAprsSymbol } = await loadShared();
  const escape = (value) => value;

  assert.equal(aprsSymbolSprite("/", " "), null);
  assert.equal(aprsSymbolSprite("/", ""), null);
  assert.equal(aprsSymbolSprite("/", "ab"), null);
  assert.equal(aprsSymbolSprite(null, ">"), null);

  assert.equal(renderLocalAprsSymbol({ symbolTable: "/", symbolCode: " " }, escape),
    '<span class="aprs-symbol aprs-symbol-local" title="Primary APRS symbol  "> </span>');
  assert.equal(renderLocalAprsSymbol({}, escape), "");
});

test("rendered symbols carry a sprite class and an inline cell offset", async () => {
  const { renderLocalAprsSymbol } = await loadShared();
  const html = renderLocalAprsSymbol({ symbolTable: "/", symbolCode: ">" }, (value) => value);

  assert.match(html, /class="aprs-symbol aprs-symbol-primary"/);
  assert.match(html, /style="background-position:-312px -24px"/);
  assert.match(html, /aria-label="Primary APRS symbol \/>"/);
  assert.equal(html.includes("http"), false);
});

// The cell offsets are computed in the bundles, so the sheet URLs and the grid
// geometry have to stay in lockstep with them here.
test("the stylesheet serves every sheet locally at the sprite geometry", async () => {
  const css = await readFile(stylePath, "utf8");

  assert.match(css, /\.aprs-symbol\s*\{[^}]*background-size:\s*384px 144px/);
  for (const sheet of ["24-0", "24-1", "24-2", "24-0-2x", "24-1-2x", "24-2-2x"]) {
    assert.ok(css.includes(`url('/vendor/aprs-symbols-${sheet}.png')`), `missing sheet ${sheet}`);
  }
  assert.match(css, /\.aprs-symbol-overlaid\s*\{[^}]*aprs-symbols-24-2\.png'\), url\('\/vendor\/aprs-symbols-24-1\.png'\)/);
});