<?php

/**
 * the platform — STANDALONE eligible-pool verifier (no framework, no deps).
 *
 * For the LIVE-RNG draw, the eligible pool is committed at close: an anonymised
 * manifest of {number, ref} (ref = opaque, non-reversible holder reference — no PII)
 * whose hash is published BEFORE the draw. After the draw the full manifest is
 * published, so anyone can:
 *   (a) recompute the commitment from the manifest and confirm it matches what was
 *       published at close — proving the pool didn't change; and
 *   (b) confirm the winning number was one of the eligible entries.
 *
 * Commitment = SHA256 of the manifest rows sorted by number ascending, each rendered
 * "number:ref", joined by newlines (identical to App\Services\PoolCommitmentService).
 *
 * Usage:
 *   php verify-pool.php <manifest.json> [expected_commitment] [winning_number]
 *
 *   <manifest.json>        JSON array: [{"number":1,"ref":"..."}, ...]
 *   [expected_commitment]  the pool_commitment published at close (optional — compares)
 *   [winning_number]       the published winning number (optional — confirms it's in the pool)
 */

if ($argc < 2 || $argc > 4) {
    fwrite(STDERR, "Usage: php verify-pool.php <manifest.json> [expected_commitment] [winning_number]\n");
    exit(2);
}

$path = $argv[1];
if (! is_file($path)) {
    fwrite(STDERR, "Manifest file not found: {$path}\n");
    exit(2);
}

$manifest = json_decode((string) file_get_contents($path), true);
if (! is_array($manifest) || $manifest === []) {
    fwrite(STDERR, "Manifest is not a non-empty JSON array.\n");
    exit(2);
}

// Canonical commitment: rows sorted by number asc, "number:ref" lines joined by \n.
usort($manifest, static fn ($a, $b) => ((int) $a['number']) <=> ((int) $b['number']));

$lines = [];
$numbers = [];
foreach ($manifest as $row) {
    if (! isset($row['number'], $row['ref'])) {
        fwrite(STDERR, "Every manifest row must have 'number' and 'ref'.\n");
        exit(2);
    }
    $n = (int) $row['number'];
    $lines[] = $n.':'.$row['ref'];
    $numbers[$n] = true;
}

$commitment = hash('sha256', implode("\n", $lines));

echo 'eligible_count: '.count($manifest)."\n";
echo 'pool_commitment (recomputed): '.$commitment."\n";

$exit = 0;

if ($argc >= 3) {
    $expected = $argv[2];
    $match = hash_equals($expected, $commitment);
    echo 'expected_commitment: '.$expected."\n";
    echo 'COMMITMENT_MATCH: '.($match ? 'yes' : 'NO — pool has been altered')."\n";
    if (! $match) {
        $exit = 1;
    }
}

if ($argc === 4) {
    $winning = (int) $argv[3];
    $inPool = isset($numbers[$winning]);
    echo 'winning_number: '.$winning."\n";
    echo 'WINNING_NUMBER_IN_POOL: '.($inPool ? 'yes' : 'NO')."\n";
    if (! $inPool) {
        $exit = 1;
    }
}

exit($exit);