// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License version 2 as
// published by the Free Software Foundation.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.

// Run: node desktop/modules/appearance/test_transitions.js
// TransitionPick.js is a QML library, so its .pragma line is stripped before
// node evaluates it.

const fs = require("fs");
const assert = require("assert");

const src = fs.readFileSync(__dirname + "/TransitionPick.js", "utf8").replace(/^\.pragma library$/m, "");
const T = new Function(src + "\nreturn { choose, clean };")();

// A named pick is returned as it is, whatever the pool holds.
assert.strictEqual(T.choose("melt", [], "melt"), "melt");

// Random stays in the pool and never plays the same one twice running.
const pool = ["ink", "melt", "blinds"];
let last = "";
const seen = {};
for (let i = 0; i < 500; i++) {
    const n = T.choose("random", pool, last);
    assert.ok(pool.indexOf(n) >= 0, `${n} is not in the pool`);
    assert.notStrictEqual(n, last, `${n} twice running`);
    seen[n] = true;
    last = n;
}
assert.strictEqual(Object.keys(seen).length, 3);

// A pool of one has to repeat, and an empty one falls back.
assert.strictEqual(T.choose("random", ["ink"], "ink"), "ink");
assert.strictEqual(T.choose("random", [], "ink"), "burn");

// Saved values: missing, wrong and unknown all land on something playable,
// and the pool comes back in the list's order.
const names = ["burn", "ink", "melt"];
assert.deepStrictEqual(T.clean(null, names), { pick: "burn", pool: names });
assert.deepStrictEqual(T.clean({ pick: "gone", pool: "x" }, names), { pick: "burn", pool: names });
assert.deepStrictEqual(T.clean({ pick: "random", pool: ["melt", "gone", "burn"] }, names),
    { pick: "random", pool: ["burn", "melt"] });
assert.deepStrictEqual(T.clean({ pick: "ink", pool: [] }, names), { pick: "ink", pool: [] });

console.log("ok");