<?php
/**
 * Prweb_Pds_Debug_Log — rolling debug log for PDS API calls.
 *
 * Writes the most recent 10 request/response pairs to
 * `<uploads>/prweb-private/api_debug.json` with secrets scrubbed. Pulled
 * out of Prweb_Pds_Client so the transport class stays under the 500-line cap.
 *
 * The directory name carries the brand prefix because the uploads folder is
 * shared with every other plugin on the install — the same reason option keys
 * and script handles do. It shipped as `webapp-private` until ORL-229; the
 * migration in includes/migrations/ renames it forward and uninstall.php
 * removes every spelling.
 *
 * @package Prweb
 */

declare(strict_types=1);

defined( 'ABSPATH' ) || exit;

class Prweb_Pds_Debug_Log {

    /** Suffix appended to the brand's storage prefix, e.g. `prweb-private`. */
    private const LOG_DIR_SUFFIX = '-private';
    private const LOG_FILE       = 'api_debug.json';
    private const KEEP_ENTRIES = 10;

    private const SECRET_KEYS = [
        'ownerPassword', 'sellerPassword', 'buyerPassword',
        'ownerCredentials', 'sellerCredentials', 'buyerCredentials',
        'userCredentials', 'senderCredentials', 'funderCredentials',
        'prvKey', 'privateKey', 'prv_key',
        'access_token', 'refresh_token', 'code', 'code_verifier', 'client_secret',
    ];

    /**
     * Directory name under `<uploads>`, current spelling.
     * Derived from the generated storage prefix so a future prefix move takes
     * this with it rather than leaving a stale folder in every publisher's
     * uploads. ORL-213 missed it precisely because it is filesystem state.
     */
    public static function log_dir_name(): string {
        return rtrim( Prweb_Brand::OPTION_PREFIX, '_' ) . self::LOG_DIR_SUFFIX;
    }

    /** Every spelling this directory has shipped under, current first. */
    public static function log_dir_candidates(): array {
        $names = [ self::log_dir_name() ];
        foreach ( Prweb_Brand::LEGACY_OPTION_PREFIXES as $legacy ) {
            $names[] = rtrim( $legacy, '_' ) . self::LOG_DIR_SUFFIX;
        }
        return array_values( array_unique( $names ) );
    }

    public static function record( string $endpoint, array $args, mixed $response ): void {
        $upload   = wp_upload_dir();
        $log_dir  = trailingslashit( $upload['basedir'] ) . self::log_dir_name();
        $log_file = $log_dir . '/' . self::LOG_FILE;

        if ( ! file_exists( $log_dir ) ) {
            wp_mkdir_p( $log_dir );
            @file_put_contents( $log_dir . '/.htaccess', "Require all denied\n" );
            @file_put_contents( $log_dir . '/index.php', "<?php // silence is golden\n" );
        }

        $entry = [
            'timestamp' => gmdate( 'Y-m-d H:i:s' ),
            'endpoint'  => $endpoint,
            'method'    => $args['method'],
            'headers'   => self::redact_headers( $args['headers'] ?? [] ),
            'request'   => self::redact( $args['body'] ?? null ),
            'response'  => self::redact( $response ),
        ];
        $log = [];
        if ( file_exists( $log_file ) ) {
            $log = json_decode( (string) file_get_contents( $log_file ), true );
            if ( ! is_array( $log ) ) {
                $log = [];
            }
        }
        array_unshift( $log, $entry );
        $log = array_slice( $log, 0, self::KEEP_ENTRIES );
        @file_put_contents( $log_file, json_encode( $log, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES ) );
    }

    /** Redact secret-looking fields recursively so debug logs are safe to share. */
    public static function redact( mixed $data ): mixed {
        if ( is_string( $data ) ) {
            $decoded = json_decode( $data, true );
            if ( is_array( $decoded ) ) {
                return self::redact_array( $decoded );
            }
            return $data;
        }
        if ( is_array( $data ) ) {
            return self::redact_array( $data );
        }
        if ( is_object( $data ) ) {
            return self::redact_array( (array) $data );
        }
        return $data;
    }

    private static function redact_array( array $data ): array {
        foreach ( $data as $k => $v ) {
            if ( is_string( $k ) && strcasecmp( $k, 'Authorization' ) === 0 && is_string( $v ) ) {
                $data[ $k ] = '[REDACTED]';
                continue;
            }
            if ( in_array( $k, self::SECRET_KEYS, true ) && is_string( $v ) ) {
                $data[ $k ] = '«redacted»';
            } elseif ( is_array( $v ) ) {
                $data[ $k ] = self::redact_array( $v );
            } elseif ( is_object( $v ) ) {
                $data[ $k ] = self::redact_array( (array) $v );
            }
        }
        return $data;
    }

    /** Header redaction: scrub Authorization (any case) before logging. */
    public static function redact_headers( array $headers ): array {
        foreach ( $headers as $k => $v ) {
            if ( is_string( $k ) && strcasecmp( $k, 'Authorization' ) === 0 && is_string( $v ) ) {
                $headers[ $k ] = '[REDACTED]';
            }
        }
        return $headers;
    }
}