/**
 * Verifies every published Zener trial against its commitment.
 *
 *   npx tsx analysis/verify-zener.ts                    # against the live data
 *   npx tsx analysis/verify-zener.ts trials.csv         # or a saved file
 *
 * This is the script the fairness claim rests on. EXP-003 shows each
 * participant a SHA-256 hash before they guess, and reveals the card and nonce
 * afterwards. If hash(card + ":" + nonce) equals the commitment, that card
 * cannot have been chosen after the guess — the server would have had to find
 * a second pair colliding under SHA-256.
 *
 * Nothing here trusts us: it recomputes every hash from the published file. A
 * single mismatch would mean a trial's card was altered after the fact, and
 * this prints it rather than summarising it away.
 */

import { createHash } from "node:crypto";
import { readFile } from "node:fs/promises";

const DATA_URL = "https://occultresearch.org/api/data/psychic-self-test";

type Trial = {
  entryDate: string;
  participantKey: string;
  commitment: string;
  nonce: string;
  card: string;
  guess: string;
  isHit: boolean;
};

function parseCsv(text: string): Trial[] {
  const rows: Trial[] = [];

  for (const line of text.split(/\r?\n/)) {
    if (!line || line.startsWith("#") || line.startsWith("entry_date")) continue;

    const cells: string[] = [];
    let cell = "";
    let inQuotes = false;

    for (let i = 0; i < line.length; i++) {
      const ch = line[i];
      if (inQuotes) {
        if (ch === '"' && line[i + 1] === '"') {
          cell += '"';
          i++;
        } else if (ch === '"') inQuotes = false;
        else cell += ch;
      } else if (ch === '"') inQuotes = true;
      else if (ch === ",") {
        cells.push(cell);
        cell = "";
      } else cell += ch;
    }
    cells.push(cell);

    if (cells.length < 7) continue;
    rows.push({
      entryDate: cells[0],
      participantKey: cells[1],
      commitment: cells[2],
      nonce: cells[3],
      card: cells[4],
      guess: cells[5],
      isHit: cells[6] === "1",
    });
  }

  return rows;
}

const sha256 = (input: string) => createHash("sha256").update(input, "utf8").digest("hex");

async function main() {
  const source = process.argv[2];
  const text = source
    ? await readFile(source, "utf8")
    : await fetch(DATA_URL).then((r) => {
        if (!r.ok) throw new Error(`open data unavailable: HTTP ${r.status}`);
        return r.text();
      });

  const trials = parseCsv(text);

  console.log("\nEXP-003 — commitment verification");
  console.log("Protocol: protocols/EXP-003.md §4\n");

  if (trials.length === 0) {
    console.log("No trials published yet.\n");
    return;
  }

  const failures: Trial[] = [];
  const scoringErrors: Trial[] = [];
  const cardCounts = new Map<string, number>();

  for (const trial of trials) {
    if (sha256(`${trial.card}:${trial.nonce}`) !== trial.commitment) failures.push(trial);
    // The recorded outcome must also match the revealed card and guess.
    if ((trial.card === trial.guess) !== trial.isHit) scoringErrors.push(trial);
    cardCounts.set(trial.card, (cardCounts.get(trial.card) ?? 0) + 1);
  }

  const hits = trials.filter((t) => t.isHit).length;
  console.log(`Trials verified        ${trials.length.toLocaleString("en-US")}`);
  console.log(`Commitment mismatches  ${failures.length}`);
  console.log(`Scoring mismatches     ${scoringErrors.length}`);
  console.log(`Observed hit rate      ${((hits / trials.length) * 100).toFixed(2)}%  (chance 20.00%)`);

  // §8: a biased generator would look exactly like an effect, so the card
  // distribution is part of the verification rather than a footnote.
  console.log("\nDealt-card frequencies (each should sit near 20%)");
  for (const [card, count] of [...cardCounts.entries()].sort()) {
    const share = (count / trials.length) * 100;
    console.log(`  ${card.padEnd(8)} ${String(count).padStart(7)}  ${share.toFixed(2)}%`);
  }

  if (failures.length > 0) {
    console.log("\nMISMATCHED COMMITMENTS — each of these is a broken fairness claim:");
    for (const trial of failures.slice(0, 20)) {
      console.log(`  ${trial.entryDate} ${trial.participantKey} card=${trial.card} commitment=${trial.commitment}`);
    }
    if (failures.length > 20) console.log(`  … and ${failures.length - 20} more`);
    process.exit(1);
  }

  console.log("\n  → Every commitment matches. No card in this file could have been");
  console.log("    chosen after the guess it was scored against.\n");
}

main().catch((error) => {
  console.error(error instanceof Error ? error.message : error);
  process.exit(1);
});