<?php
/**
 * Core Operational File Streaming and Download Asset Suite
 *
 * @package af-translate
 */

if ( ! defined( 'ABSPATH' ) ) { 
    exit; 
}

class AF_Translate_File_Streaming {

    /**
     * Map operational plugin hooks to core admin post download gateways.
     */
    public static function init_hooks() {
        add_action( 'admin_post_af_translate_download_pot', array( __CLASS__, 'process_pot_export' ) );
        add_action( 'admin_post_af_translate_download_po_bundle', array( __CLASS__, 'process_po_zip_bundle_export' ) );
    }

    /**
     * Streams standalone textual POT catalog templates straight to the user browser.
     * Generates a template on the fly inside the sandbox if the extension lacks one.
     */
    public static function process_pot_export() {
        // 1. Authenticate Administrative Operational Capability Clearance
        if ( ! current_user_can( 'manage_options' ) ) { 
            wp_die( esc_html__( 'Forbidden operational capability clearance context.', 'af-translate' ) ); 
        }
        
        check_admin_referer( 'af_translate_download_pot_nonce' );

        $component = isset( $_GET['component'] ) ? sanitize_key( wp_unslash( $_GET['component'] ) ) : '';
        $type      = isset( $_GET['type'] ) ? sanitize_key( wp_unslash( $_GET['type'] ) ) : 'theme';
        $summary   = AF_Translate_Analyzer::get_component_summary( $component, $type );

        $pot_file_path = ! empty( $summary['pot_file'] ) ? $summary['pot_file'] : '';

        // --- ON-THE-FLY GENERATION FALLBACK MATRIX ---
        if ( empty( $pot_file_path ) || ! file_exists( $pot_file_path ) ) {
            $sub_folder  = ( 'plugin' === $type ) ? 'plugins' : 'themes';
            $upload_dir  = wp_upload_dir();
            $sandbox_dir = trailingslashit( $upload_dir['basedir'] ) . "af-translate/{$sub_folder}";

            if ( ! is_dir( $sandbox_dir ) ) {
                wp_mkdir_p( $sandbox_dir );
                file_put_contents( $sandbox_dir . '/index.php', '' ); // 0-byte directory protect
            }

            // Define target path for our generated POT inside our safe upload sandbox space
            $pot_file_path = $sandbox_dir . '/' . $component . '.pot';

            // Check if we haven't generated it yet in this request loop
            if ( ! file_exists( $pot_file_path ) ) {
                // die('here we go');
                if ( class_exists( 'AF_Translate_POT_Generator' ) ) {
                    // Call your extraction engine to parse the extension code files and create the .pot file
                    $generated = AF_Translate_POT_Generator::generate_master_pot( $component, $type, $pot_file_path );
                    if ( ! $generated ) {
                        wp_die( esc_html__( 'Critical Error: Code execution engine failed to build translation map template.', 'af-translate' ) );
                    }
                } else {
                    wp_die( esc_html__( 'Configuration baseline failure: Translation parsing engine is unavailable.', 'af-translate' ) );
                }
            }
        }

        // Resilient Path Security Interceptor Cross-Check
        $is_pot_safe = false;
        if ( class_exists( 'AF_Translate_Path_Validator' ) ) {
            $is_pot_safe = AF_Translate_Path_Validator::validate_containment( $pot_file_path, false );
        }

        if ( ! $is_pot_safe ) {
            wp_die( esc_html__( 'Security Guardrail: Path containment validation failure.', 'af-translate' ) );
        }

        // 3. Purge Active Output Buffer Layers to Prevent File Corruption
        while ( ob_get_level() ) {
            ob_end_clean();
        }

        // 4. Emit Safe Stream Headers
        header( 'Content-Type: text/plain; charset=utf-8' );
        header( 'Content-Disposition: attachment; filename="' . basename( $pot_file_path ) . '"' );
        header( 'Pragma: no-cache' );
        header( 'Expires: 0' );
        
        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_readfile -- Direct file stream passthru required for memory-efficient browser download proxying.
        readfile( $pot_file_path );
        exit;
    }

    /**
     * Bundles matching PO/MO elements together on the fly inside a secure compressed ZIP wrapper.
     */
    public static function process_po_zip_bundle_export() {
        // 1. Authenticate Administrative Operational Capability Clearance
        if ( ! current_user_can( 'manage_options' ) ) { 
            wp_die( esc_html__( 'Forbidden operational capability clearance context.', 'af-translate' ) ); 
        }
        
        check_admin_referer( 'af_translate_download_po_nonce' );

        $filename  = isset( $_GET['filename'] ) ? sanitize_text_field( wp_unslash( $_GET['filename'] ) ) : ''; // e.g. "ar.po" or "covernews-ar.po"
        $component = isset( $_GET['component'] ) ? sanitize_key( wp_unslash( $_GET['component'] ) ) : '';     // e.g. "covernews"
        $type      = isset( $_GET['type'] ) ? sanitize_key( wp_unslash( $_GET['type'] ) ) : 'theme';          // e.g. "theme"

        // --- STEP 2: SANDBOX-FIRST RESOLUTION CASCADE ---
        $sub_folder  = ( 'plugin' === $type ) ? 'plugins' : 'themes';
        $upload_dir  = wp_upload_dir();
        $sandbox_dir = trailingslashit( $upload_dir['basedir'] ) . "af-translate/{$sub_folder}";

        // Parse clean language keys to test unified structural names
        $pure_name             = basename( $filename, '.po' );
        $locale                = str_replace( $component . '-', '', $pure_name );
        $standardized_filename = $component . '-' . $locale . '.po';

        $candidates = array();

        // Priority 1 & 2: Look inside our custom sandboxed uploads directory first!
        $candidates[] = $sandbox_dir . '/' . $standardized_filename;
        $candidates[] = $sandbox_dir . '/' . $filename;

        // Priority 3+: Fall back to structural vendor plugin/theme directories
        if ( class_exists( 'AF_Translate_Analyzer' ) ) {
            $dirs = AF_Translate_Analyzer::locate_translation_dirs( $component, $type );
            if ( ! empty( $dirs ) && is_array( $dirs ) ) {
                foreach ( $dirs as $path ) {
                    $candidates[] = trailingslashit( $path ) . $filename;
                }
            }
        }

        // Loop execution matrix to extract the primary live candidate instance
        $po_target = '';
        foreach ( $candidates as $candidate ) {
            $canonical_candidate = class_exists( 'AF_Translate_Path_Validator' ) 
                ? AF_Translate_Path_Validator::resolve_canonical_path( $candidate ) 
                : $candidate;

            if ( ! empty( $canonical_candidate ) && file_exists( $canonical_candidate ) ) {
                $po_target = $canonical_candidate;
                break;
            }
        }

        if ( empty( $po_target ) ) {
            wp_die( esc_html__( 'Target translation asset mapping entry context missing.', 'af-translate' ) );
        }

        // Verify absolute system path encapsulation integrity matches safe boundaries
        $is_po_safe = false;
        if ( class_exists( 'AF_Translate_Path_Validator' ) ) {
            $is_po_safe = AF_Translate_Path_Validator::validate_containment( $po_target, false );
        } elseif ( class_exists( 'AF_Translate_Project_Config' ) ) {
            $is_po_safe = AF_Translate_Project_Config::validate_file_path_containment( $po_target );
        }

        if ( ! $is_po_safe ) {
            wp_die( esc_html__( 'Security Guardrail: Path containment validation failure.', 'af-translate' ) );
        }

        // Dynamically compute the binary partner file target based on the selected directory structure
        $mo_target = str_replace( '.po', '.mo', $po_target );
        $zip_name  = str_replace( '.po', '-translation-bundle.zip', $filename );

        // 3. Initialize the Zip Archive Class Object Context Engine
        $zip      = new ZipArchive();
        $tmp_file = wp_tempnam( $zip_name );

        if ( empty( $tmp_file ) || true !== $zip->open( $tmp_file, ZipArchive::CREATE | ZipArchive::OVERWRITE ) ) {
            wp_die( esc_html__( 'Could not open temporary engine file matrix layer safely.', 'af-translate' ) );
        }

        $zip->addFile( $po_target, basename( $po_target ) );
        
        // Match and inject compiled binary machine code pairs automatically
        if ( file_exists( $mo_target ) ) {
            $is_mo_safe = false;
            if ( class_exists( 'AF_Translate_Path_Validator' ) ) {
                $is_mo_safe = AF_Translate_Path_Validator::validate_containment( $mo_target, false );
            } elseif ( class_exists( 'AF_Translate_Project_Config' ) ) {
                $is_mo_safe = AF_Translate_Project_Config::validate_file_path_containment( $mo_target );
            }

            if ( $is_mo_safe ) {
                $zip->addFile( $mo_target, basename( $mo_target ) );
            }
        }
        
        $zip->close();

        // 4. CRITICAL: Purge Active Output Buffer Layers to Secure ZIP Integrity
        while ( ob_get_level() ) {
            ob_end_clean();
        }

        // 5. Emit Stream Transmission Payload Control Headers
        header( 'Content-Type: application/zip' );
        header( 'Content-Disposition: attachment; filename="' . basename( $zip_name ) . '"' );
        header( 'Content-Length: ' . filesize( $tmp_file ) );
        header( 'Pragma: no-cache' );
        header( 'Expires: 0' );

        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_readfile -- Direct file stream passthru required for memory-efficient browser download proxying.
        readfile( $tmp_file );

        wp_delete_file( $tmp_file ); 
        exit;
    }
}