<?php
use ParagonIE\Gossamer\Client\AttestPolicy;
use ParagonIE\Gossamer\Client\PolicyRules\AttestedAt;
use ParagonIE\Gossamer\Client\PolicyRules\AttestedAtOrAbove;
use ParagonIE\Gossamer\Client\PolicyRules\GroupAnd;
use ParagonIE\Gossamer\Client\PolicyRules\GroupOr;
use ParagonIE\Gossamer\Client\PolicyRules\Not;
use ParagonIE\Gossamer\Client\TrustMode\LocalTrust;
use ParagonIE\Gossamer\Db\PDO as PDOAdapter;

// Trust mode (local for simplicity)
$db = new PDOAdapter(new PDO('sqlite:/path/to/database.sql'));
$myTrustMode = new LocalTrust($db);

// Attestation Policy:
$myAttestPolicy = (new AttestPolicy())
    ->addRule(
        new GroupAnd(
            new AttestedAt(
                AttestPolicy::REPRODUCED,
                ['reproduced-bot']
            ),
            new GroupOr(
                new AttestedAtOrAbove(
                    AttestPolicy::SPOT_CHECK,
                    ['paragonie', 'symfony', 'laravel', 'ncc'],
                    2
                ),
                new AttestedAtOrAbove(
                    AttestPolicy::CODE_REVIEW,
                    ['paragonie', 'ncc']
                )
            ),
            new Not(
                new AttestedAt(
                    AttestPolicy::VOTE_AGAINST,
                    ['jedisct1', 'muglug']
                )
            )
        )
    );

// Instantiate via dependency injection:
$gossamer = new GossamerClient(
    $myTrustMode,
    $myAttestPolicy
);

// Get an update record from the transparency log:
$record = $gossamer->getUpdate('symfony/polyfill-php80', 'v1.20.0');

// If it's valid...
if ($record->isFileValid($file)) {
    // Install it!
    my_custom_installer($file);
}