// Any browser console or node 18+ — no library, none of our code.
// Recompute a round's outcome hash and compare it to the one we showed.
const clientSeed = "your-client-seed";
const serverSeed = "the-revealed-server-seed";
const nonce = 1234;

const data = new TextEncoder().encode(`${clientSeed}:${serverSeed}:${nonce}`);
crypto.subtle.digest("SHA-256", data).then((buf) => {
    const hash = Array.from(new Uint8Array(buf))
        .map((b) => b.toString(16).padStart(2, "0"))
        .join("");
    console.log("outcome hash:", hash);
});

// A matching hash proves the round came from these exact inputs.
// The roll derived from it needs the seedrandom package (not built into
// consoles), so that half runs in node:
//   npm i seedrandom
//   node -e "console.log(require('seedrandom')('PASTE_OUTCOME_HASH')())"

// Any browser console or node 18+ — no library, none of our code.
const key = "the-revealed-key";
const salt = "the-revealed-salt";
const blockHash = "the-eos-block-hash";

const sha256hex = async (text) => {
    const buf = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(text));
    return Array.from(new Uint8Array(buf))
        .map((b) => b.toString(16).padStart(2, "0"))
        .join("");
};

// The commitment shown during the countdown:
sha256hex(`${key}:${salt}`).then((h) => console.log("commitment:", h));
// The outcome hash the battle's rolls are seeded from:
sha256hex(`${key}:${salt}:${blockHash}`).then((h) => console.log("outcome:", h));

// The rolls themselves need seedrandom (node):
//   npm i seedrandom
//   node -e "const r=require('seedrandom')('PASTE_OUTCOME_HASH'); for (let i=0;i<5;i++) console.log(r())"

// Any browser console or node 18+ — no library at all for this one.
// Hashing THIS round's revealed hash must reproduce the hash that was
// already published for the round BEFORE it — one link of the chain.
const roundHash = "this-rounds-revealed-hash";

crypto.subtle.digest("SHA-256", new TextEncoder().encode(roundHash)).then((buf) => {
    const prev = Array.from(new Uint8Array(buf))
        .map((b) => b.toString(16).padStart(2, "0"))
        .join("");
    console.log("previous round's hash:", prev);
});

// The multiplier is pure arithmetic on the hash — also no library:
//   const max = 2n ** 52n;
//   const n = (BigInt("0x" + roundHash) % max) + 1n;
//   console.log("multiplier:", Number((100n * max) / n) / 100);