<?php
define('EASYPOST_ENDPOINT_CONFIG', '{"endpoint_version":"2026.06.05","token_id":"ep_69c5f8ba92e842d5978f0c3a89b15344","token_verifier":"v1:7e86fcf84bbdff4e4659f175159df708:25e64f24f10f8bedd44b56a6f8183f3e607bc32a7f3e74931d71b695e9b08465","ota_release_public_key_pem":"-----BEGIN PUBLIC KEY-----\\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA0JTcpyvncP1Izz2SsnLq\\nGm3iObZi5YEydCeQPv0kX5pN3WwEzt/j1fsyd3EVHbLlXUmdQbWvCBIX1wq/RO4q\\n4UuLpks++nnz7pNTyZqrU+gPUlQb4uDBJsE6nePRyddoMGbT8yF4yzLt/fp86oSG\\ncd/TqnUIplM4dmQVtzqaUiGSUFLReUO0tMHvYGTRl/jCM/pJmIMNLEFmAb/x6wT4\\nihEIXD39Uj2/BG/zJFiIc6FNvqRp1DRm50lhPJW7LkDin+LkvSebbIubeYEe3vc9\\n7qX0zD2zpTFv04itmPld0eOa7kXHNsr+jUnTmuovzdIzBJjcgSWT/nqI+bRAXfL6\\nUwIDAQAB\\n-----END PUBLIC KEY-----"}');

function easypost_endpoint_config() {
    return json_decode(EASYPOST_ENDPOINT_CONFIG, true);
}

function easypost_endpoint_json($status, $payload) {
    http_response_code($status);
    header('Content-Type: application/json; charset=utf-8');
    echo json_encode($payload);
    exit;
}

function easypost_endpoint_header($name) {
    $key = strtolower($name);
    foreach ($_SERVER as $server_key => $value) {
        if (strpos($server_key, 'HTTP_') !== 0) {
            continue;
        }
        $normalized = strtolower(str_replace('_', '-', substr($server_key, 5)));
        if ($normalized === $key) {
            return (string) $value;
        }
    }
    return '';
}

function easypost_endpoint_wp_load_path() {
    $candidates = array(
        __DIR__ . '/wp-load.php',
        __DIR__ . '/../wp-load.php',
        __DIR__ . '/../../wp-load.php',
        __DIR__ . '/../../../wp-load.php',
        __DIR__ . '/../../../../wp-load.php',
        __DIR__ . '/../../../../../wp-load.php',
    );
    foreach ($candidates as $candidate) {
        if ($candidate && is_readable($candidate)) {
            return $candidate;
        }
    }
    return false;
}

function easypost_endpoint_bootstrap_wordpress() {
    $wp_load = easypost_endpoint_wp_load_path();
    if (!$wp_load) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'wp_load_not_found'));
    }
    require_once $wp_load;
}

function easypost_endpoint_verifier_secret($verifier) {
    $parts = explode(':', (string) $verifier, 3);
    if (count($parts) !== 3 || $parts[0] !== 'v1' || $parts[2] === '') {
        return false;
    }
    return $parts[2];
}

function easypost_endpoint_verify_auth($body) {
    $config = easypost_endpoint_config();
    $token_id = easypost_endpoint_header('x-easypost-token-id');
    $timestamp = easypost_endpoint_header('x-easypost-timestamp');
    $request_id = easypost_endpoint_header('x-easypost-request-id');
    $body_sha256 = easypost_endpoint_header('x-easypost-body-sha256');
    $signature = easypost_endpoint_header('x-easypost-signature');

    if ($token_id === '' || $timestamp === '' || $request_id === '' || $body_sha256 === '' || $signature === '') {
        easypost_endpoint_json(401, array('ok' => false, 'error' => 'missing_auth_headers'));
    }
    if (!hash_equals((string) $config['token_id'], $token_id)) {
        easypost_endpoint_json(401, array('ok' => false, 'error' => 'unknown_token'));
    }
    $request_time = strtotime($timestamp);
    if (!$request_time || abs(time() - $request_time) > 300) {
        easypost_endpoint_json(401, array('ok' => false, 'error' => 'timestamp_stale'));
    }
    $computed_body_sha256 = hash('sha256', $body);
    if (!hash_equals($computed_body_sha256, $body_sha256)) {
        easypost_endpoint_json(401, array('ok' => false, 'error' => 'body_sha256_mismatch'));
    }

    $replay_key = 'easypost_endpoint_req_' . hash('sha256', $token_id . ':' . $request_id);
    if (function_exists('get_transient') && get_transient($replay_key)) {
        easypost_endpoint_json(409, array('ok' => false, 'error' => 'duplicate_request_id'));
    }

    $secret = easypost_endpoint_verifier_secret($config['token_verifier']);
    if (!$secret) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'invalid_token_verifier'));
    }

    $path = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : '/wp-content/easypost/easypost.php';
    $signature_input = implode("\n", array(
        strtoupper($_SERVER['REQUEST_METHOD']),
        $path,
        $timestamp,
        $request_id,
        $token_id,
        $computed_body_sha256,
    ));
    $expected = hash_hmac('sha256', $signature_input, $secret);
    if (!hash_equals($expected, $signature)) {
        easypost_endpoint_json(401, array('ok' => false, 'error' => 'signature_mismatch'));
    }

    if (function_exists('set_transient')) {
        set_transient($replay_key, '1', 300);
    }
}

function easypost_endpoint_payload($body) {
    $payload = json_decode($body, true);
    if (!is_array($payload)) {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'invalid_json'));
    }
    return $payload;
}

function easypost_endpoint_health() {
    easypost_endpoint_bootstrap_wordpress();
    $config = easypost_endpoint_config();
    easypost_endpoint_json(200, array(
        'ok' => true,
        'endpointVersion' => $config['endpoint_version'],
        'tokenId' => $config['token_id'],
        'canBootstrapWordPress' => true,
        'canInsertPosts' => function_exists('wp_insert_post'),
        'siteUrl' => function_exists('site_url') ? site_url() : null,
        'phpVersion' => PHP_VERSION,
        'serverTime' => gmdate('c'),
    ));
}

function easypost_endpoint_create_post($payload) {
    easypost_endpoint_bootstrap_wordpress();
    if (!function_exists('wp_insert_post')) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'capability_failed'));
    }
    $status = 'publish';
    $post_type = !empty($payload['post_type']) ? sanitize_key($payload['post_type']) : (!empty($payload['postType']) ? sanitize_key($payload['postType']) : 'post');
    $content = isset($payload['contentHtml']) ? $payload['contentHtml'] : (isset($payload['content']) ? $payload['content'] : '');
    $postarr = array(
        'post_title' => isset($payload['title']) ? wp_strip_all_tags($payload['title']) : '',
        'post_name' => isset($payload['slug']) ? sanitize_title($payload['slug']) : '',
        'post_content' => $content,
        'post_status' => $status,
        'post_type' => $post_type,
    );
    if (!empty($payload['date'])) {
        $postarr['post_date'] = $payload['date'];
    } elseif (!empty($payload['publicationDate'])) {
        $postarr['post_date'] = $payload['publicationDate'];
    }
    $post_id = wp_insert_post($postarr, true);
    if (is_wp_error($post_id)) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'insert_failed', 'message' => $post_id->get_error_message()));
    }
    easypost_endpoint_json(201, array(
        'ok' => true,
        'id' => (int) $post_id,
        'postId' => (int) $post_id,
        'link' => get_permalink($post_id),
        'postUrl' => get_permalink($post_id),
        'slug' => get_post_field('post_name', $post_id),
        'status' => get_post_status($post_id),
        'created' => true,
    ));
}

function easypost_endpoint_verify_release_signature($payload, $computed_sha256) {
    $config = easypost_endpoint_config();
    if (empty($config['ota_release_public_key_pem']) || !is_string($config['ota_release_public_key_pem'])) {
        easypost_endpoint_json(501, array('ok' => false, 'error' => 'ota_release_public_key_missing'));
    }
    if (!function_exists('openssl_verify')) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'openssl_unavailable'));
    }
    if (!isset($payload['signature']) || !is_string($payload['signature']) || trim($payload['signature']) === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'release_signature_required'));
    }

    $signature = base64_decode($payload['signature'], true);
    if ($signature === false || $signature === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'release_signature_invalid'));
    }

    $signed_payload = $payload['version'] . "\n" . $computed_sha256;
    $verified = openssl_verify($signed_payload, $signature, $config['ota_release_public_key_pem'], OPENSSL_ALGO_SHA256);
    if ($verified !== 1) {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'release_signature_invalid'));
    }
}

function easypost_endpoint_update_endpoint($payload) {
    if (!isset($payload['version']) || !is_string($payload['version']) || trim($payload['version']) === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'version_required'));
    }
    if (!isset($payload['sha256']) || !is_string($payload['sha256']) || trim($payload['sha256']) === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'sha256_required'));
    }
    if (!preg_match('/\A[a-f0-9]{64}\z/', $payload['sha256'])) {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'sha256_invalid'));
    }
    if (!isset($payload['phpBase64']) || !is_string($payload['phpBase64']) || trim($payload['phpBase64']) === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'php_base64_required'));
    }

    $decoded_php = base64_decode($payload['phpBase64'], true);
    if ($decoded_php === false || $decoded_php === '') {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'php_base64_invalid'));
    }
    $computed_sha256 = hash('sha256', $decoded_php);
    if (!hash_equals($payload['sha256'], $computed_sha256)) {
        easypost_endpoint_json(400, array('ok' => false, 'error' => 'sha256_mismatch'));
    }
    easypost_endpoint_verify_release_signature($payload, $computed_sha256);

    $tmp_path = tempnam(__DIR__, 'easypost-update-');
    if (!$tmp_path) {
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'temporary_write_failed'));
    }
    $bytes = file_put_contents($tmp_path, $decoded_php, LOCK_EX);
    if ($bytes === false || $bytes !== strlen($decoded_php)) {
        @unlink($tmp_path);
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'temporary_write_failed'));
    }
    @chmod($tmp_path, fileperms(__FILE__) & 0777);
    if (!rename($tmp_path, __FILE__)) {
        @unlink($tmp_path);
        easypost_endpoint_json(500, array('ok' => false, 'error' => 'rename_failed'));
    }

    easypost_endpoint_json(200, array(
        'ok' => true,
        'endpointVersion' => $payload['version'],
    ));
}

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    easypost_endpoint_json(405, array('ok' => false, 'error' => 'method_not_allowed'));
}

$body = file_get_contents('php://input');
easypost_endpoint_bootstrap_wordpress();
easypost_endpoint_verify_auth($body);
$action = isset($_GET['action']) ? $_GET['action'] : 'health';
if ($action === 'health') {
    easypost_endpoint_health();
}
$payload = easypost_endpoint_payload($body);
if ($action === 'create_post') {
    easypost_endpoint_create_post($payload);
}
if ($action === 'rotate_token') {
    easypost_endpoint_json(501, array('ok' => false, 'error' => 'rotate_token_not_implemented'));
}
if ($action === 'update_endpoint') {
    easypost_endpoint_update_endpoint($payload);
}
easypost_endpoint_json(404, array('ok' => false, 'error' => 'unknown_action'));