<?php
/**
 * Bulk tools.
 *
 * Three operations under Settings > AUM NexCart > Tools:
 *
 *  1. CSV Export — streams a CSV of every product. Synchronous;
 *     served as an attachment download.
 *
 *  2. CSV Import — uploads a CSV, stores it in a transient, then
 *     processes batches of 10 rows via AJAX with a progress bar.
 *     A failures log is returned at the end.
 *
 *  3. Rebuild Attribute Index — walks every product and rewrites
 *     the filterable shadow meta rows. Useful after changing the
 *     filterable_attributes list in settings.
 *
 * Capability gate: manage_options for all three operations.
 */

defined( 'ABSPATH' ) || exit;

class AumNexCart_Tools {

	const AJAX_IMPORT_BATCH = 'aumnexcart_import_batch';
	const AJAX_REINDEX      = 'aumnexcart_reindex';
	const NONCE_TOOLS       = 'aumnexcart_tools';

	const TRANSIENT_IMPORT  = 'aumnexcart_import_';
	const BATCH_SIZE_IMPORT = 10;
	const BATCH_SIZE_REINDEX = 20;

	/**
	 * Canonical CSV column order. Imports must match this header
	 * exactly (case-sensitive); exports use these in this order.
	 */
	const CSV_COLUMNS = array(
		'title',
		'slug',
		'status',
		'categories',
		'description',
		'price_type',
		'price_min',
		'price_max',
		'price_text',
		'price_currency',
		'attributes',
		'media_urls',
		'contact',
	);

	public function __construct() {
		add_action( 'admin_post_aumnexcart_export_csv', array( $this, 'handle_export' ) );
		add_action( 'admin_post_aumnexcart_import_upload', array( $this, 'handle_upload' ) );

		add_action( 'wp_ajax_' . self::AJAX_IMPORT_BATCH, array( $this, 'ajax_import_batch' ) );
		add_action( 'wp_ajax_' . self::AJAX_REINDEX, array( $this, 'ajax_reindex' ) );
	}

	/* ================================================================
	 * EXPORT
	 * ================================================================ */

	/**
	 * Streams the CSV directly to the browser. Uses php://output so
	 * memory stays bounded even with thousands of products.
	 */
	public function handle_export() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Insufficient permissions.', 'aumnexcart' ) );
		}
		check_admin_referer( self::NONCE_TOOLS );

		$filename = 'aumnexcart-products-' . gmdate( 'Y-m-d' ) . '.csv';

		nocache_headers();
		header( 'Content-Type: text/csv; charset=utf-8' );
		header( 'Content-Disposition: attachment; filename=' . $filename );

		/*
		 * No phpcs:ignore needed on this line: WPCS's AlternativeFunctions sniff keeps
		 * `php://output` on an allowlist, so opening it is never reported as a filesystem call.
		 * The writes below it are reported, and carry their own reason.
		 */
		$out = fopen( 'php://output', 'w' );

		/* BOM for Excel UTF-8 compatibility */
		// phpcs:ignore WordPress.WP.AlternativeFunctions -- this is the CSV download stream, not the filesystem: the handle is php://output, opened after the Content-Disposition header above, so every write goes straight to the browser. WP_Filesystem abstracts disk access (and FTP/SSH credentials) and has no path for an output stream.
		fwrite( $out, "\xEF\xBB\xBF" );
		fputcsv( $out, self::CSV_COLUMNS );

		$paged = 1;
		do {
			$q = new WP_Query(
				array(
					'post_type'      => AumNexCart_Post_Type::POST_TYPE,
					'post_status'    => array( 'publish', 'draft', 'pending', 'private' ),
					'posts_per_page' => 50,
					'paged'          => $paged,
					'no_found_rows'  => true,
					'orderby'        => 'ID',
					'order'          => 'ASC',
				)
			);
			if ( ! $q->have_posts() ) {
				break;
			}
			foreach ( $q->posts as $post ) {
				fputcsv( $out, self::row_for_post( $post ) );
			}
			$paged++;
			if ( count( $q->posts ) < 50 ) {
				break;
			}
		} while ( true );

		// phpcs:ignore WordPress.WP.AlternativeFunctions -- this is the CSV download stream, not the filesystem: the handle is php://output, opened after the Content-Disposition header above, so every write goes straight to the browser. WP_Filesystem abstracts disk access (and FTP/SSH credentials) and has no path for an output stream.
		fclose( $out );
		exit;
	}

	/**
	 * Builds one CSV row from a post.
	 *
	 * @param WP_Post $post
	 * @return array
	 */
	private static function row_for_post( $post ) {
		$cats = wp_get_object_terms( $post->ID, AumNexCart_Post_Type::TAXONOMY, array( 'fields' => 'names' ) );
		if ( is_wp_error( $cats ) ) {
			$cats = array();
		}

		$price = AumNexCart_Meta::get_price( $post->ID );
		$media = AumNexCart_Meta::get_media( $post->ID );
		$urls  = array();
		foreach ( $media as $m ) {
			$urls[] = $m['url'];
		}

		return array(
			$post->post_title,
			$post->post_name,
			$post->post_status,
			implode( '|', $cats ),
			$post->post_content,
			$price['type'],
			$price['min'],
			$price['max'],
			$price['text'],
			$price['currency'],
			wp_json_encode( AumNexCart_Meta::get_attributes( $post->ID ) ),
			implode( '|', $urls ),
			wp_json_encode(
				array_map(
					function ( $r ) {
						return array(
							'type'  => $r['type'],
							'label' => $r['label'],
							'value' => $r['value'],
						);
					},
					AumNexCart_Meta::get_contact( $post->ID )
				)
			),
		);
	}

	/* ================================================================
	 * IMPORT
	 * ================================================================ */

	/**
	 * Receives the uploaded CSV, validates the header, parses all
	 * rows into a transient, and redirects to the Tools tab with
	 * the import token in the URL so JS can begin processing.
	 */
	public function handle_upload() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Insufficient permissions.', 'aumnexcart' ) );
		}
		check_admin_referer( self::NONCE_TOOLS );

		if ( empty( $_FILES['aumnexcart_csv']['tmp_name'] ) ) {
			self::redirect_tools( array( 'import_error' => 'no_file' ) );
		}

		$path = sanitize_text_field( wp_unslash( $_FILES['aumnexcart_csv']['tmp_name'] ) );
		// phpcs:ignore WordPress.WP.AlternativeFunctions -- reading PHP's own upload temp file ($_FILES['tmp_name']) row by row. WP_Filesystem can only hand back the whole file at once (get_contents_array), which would put an arbitrarily large catalogue import in memory, and fgetcsv needs a handle. The path never comes from user input.
		$fh   = fopen( $path, 'r' );
		if ( ! $fh ) {
			self::redirect_tools( array( 'import_error' => 'unreadable' ) );
		}

		$header = fgetcsv( $fh );
		if ( ! $header ) {
			// phpcs:ignore WordPress.WP.AlternativeFunctions -- reading PHP's own upload temp file ($_FILES['tmp_name']) row by row. WP_Filesystem can only hand back the whole file at once (get_contents_array), which would put an arbitrarily large catalogue import in memory, and fgetcsv needs a handle. The path never comes from user input.
			fclose( $fh );
			self::redirect_tools( array( 'import_error' => 'empty' ) );
		}
		/* Strip BOM from first header cell if present */
		if ( isset( $header[0] ) ) {
			$header[0] = preg_replace( '/^\xEF\xBB\xBF/', '', $header[0] );
		}

		$expected = self::CSV_COLUMNS;
		$matches  = array_map( 'strval', array_slice( $header, 0, count( $expected ) ) );
		if ( $matches !== $expected ) {
			// phpcs:ignore WordPress.WP.AlternativeFunctions -- reading PHP's own upload temp file ($_FILES['tmp_name']) row by row. WP_Filesystem can only hand back the whole file at once (get_contents_array), which would put an arbitrarily large catalogue import in memory, and fgetcsv needs a handle. The path never comes from user input.
			fclose( $fh );
			self::redirect_tools( array( 'import_error' => 'bad_header' ) );
		}

		$rows = array();
		while ( ( $row = fgetcsv( $fh ) ) !== false ) {
			if ( count( array_filter( $row, 'strlen' ) ) === 0 ) {
				continue;
			}
			$rows[] = $row;
		}
		// phpcs:ignore WordPress.WP.AlternativeFunctions -- reading PHP's own upload temp file ($_FILES['tmp_name']) row by row. WP_Filesystem can only hand back the whole file at once (get_contents_array), which would put an arbitrarily large catalogue import in memory, and fgetcsv needs a handle. The path never comes from user input.
		fclose( $fh );

		if ( empty( $rows ) ) {
			self::redirect_tools( array( 'import_error' => 'empty' ) );
		}

		$token = wp_generate_password( 12, false );
		set_transient(
			self::TRANSIENT_IMPORT . $token,
			array(
				'rows'      => $rows,
				'total'     => count( $rows ),
				'processed' => 0,
				'failed'    => array(),
				'success'   => 0,
			),
			HOUR_IN_SECONDS
		);

		self::redirect_tools( array( 'import_token' => $token ) );
	}

	/**
	 * Processes one batch of rows. Returns progress info as JSON.
	 */
	public function ajax_import_batch() {
		check_ajax_referer( self::NONCE_TOOLS, 'nonce' );
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied.', 'aumnexcart' ) ) );
		}

		$token = isset( $_POST['token'] ) ? sanitize_text_field( wp_unslash( $_POST['token'] ) ) : '';
		if ( '' === $token ) {
			wp_send_json_error( array( 'message' => __( 'Missing token.', 'aumnexcart' ) ) );
		}

		$state = get_transient( self::TRANSIENT_IMPORT . $token );
		if ( ! is_array( $state ) ) {
			wp_send_json_error( array( 'message' => __( 'Import session expired.', 'aumnexcart' ) ) );
		}

		$processed = (int) $state['processed'];
		$end       = min( $processed + self::BATCH_SIZE_IMPORT, $state['total'] );

		for ( $i = $processed; $i < $end; $i++ ) {
			$row    = $state['rows'][ $i ];
			$result = $this->import_row( $row, $i + 2 ); /* +2: header row + 1-based */
			if ( is_wp_error( $result ) ) {
				$state['failed'][] = array(
					'line'    => $i + 2,
					'message' => $result->get_error_message(),
				);
			} else {
				$state['success']++;
			}
		}

		$state['processed'] = $end;
		$done               = $end >= $state['total'];

		set_transient( self::TRANSIENT_IMPORT . $token, $state, HOUR_IN_SECONDS );

		$response = array(
			'processed' => $state['processed'],
			'total'     => $state['total'],
			'success'   => $state['success'],
			'failed'    => count( $state['failed'] ),
			'done'      => $done,
		);

		if ( $done ) {
			$response['failures'] = $state['failed'];
			delete_transient( self::TRANSIENT_IMPORT . $token );
		}

		wp_send_json_success( $response );
	}

	/**
	 * Imports one CSV row.
	 *
	 * @param array $row
	 * @param int   $line Line number in original file (for error reporting).
	 * @return int|WP_Error Post ID on success.
	 */
	private function import_row( $row, $line ) {
		$cols = array_combine(
			self::CSV_COLUMNS,
			array_pad( array_slice( $row, 0, count( self::CSV_COLUMNS ) ), count( self::CSV_COLUMNS ), '' )
		);

		if ( '' === trim( (string) $cols['title'] ) ) {
			/* translators: %d: line number in the CSV file */
			return new WP_Error( 'no_title', sprintf( __( 'Line %d: missing title.', 'aumnexcart' ), $line ) );
		}

		$status = in_array( $cols['status'], array( 'publish', 'draft', 'pending', 'private' ), true ) ? $cols['status'] : 'publish';

		/*
		 * 🔴 **CSV 的内容不是导入者打出来的，是文件给的。**
		 *
		 * `wp_insert_post()` 只对**没有** `unfiltered_html` 的用户跑 kses，而单站管理员是有的。
		 * 于是一份 CSV 里的 `<script>` 会原样进 `post_content`，再由 `the_content` 渲染出来。
		 *
		 * 「管理员本来就能在编辑器里贴脚本」这个说法在这里不成立：**他没写这个文件**。
		 * 买家导入的是我们或第三方做的 kit，他点「导入」时没读过里面每一行。
		 * 这条路径把「我信任这个管理员」偷换成了「我信任这个文件」。
		 *
		 * `wp_kses_post()` 保留正文该有的东西（段落、链接、强调、列表、图片），
		 * 去掉 `<script>` / `<style>` / `on*` 事件属性。短代码是纯文本，不受影响。
		 * 标题不该带标记，直接 `sanitize_text_field()`。
		 *
		 * 两个方向都验过（真跑 `wp_kses_post()`，不是推的）：
		 *   恶意 —— `<script>` / `onerror=` / `<style>` 全部去掉
		 *   合法 —— 段落、强调、链接、列表、图片、短代码、中日韩文字，一字未动
		 * ⚠️ 唯一一处会变的是裸 `&` → `&amp;`。那是**正确的 HTML 编码**，渲染出来还是 `&` ——
		 *    逐字节比对会把它报成「改坏了」，别据此回退。
		 *
		 * 2026-10-11 .org 审核第二轮提的（T2）。
		 */
		$post_id = wp_insert_post(
			array(
				'post_type'    => AumNexCart_Post_Type::POST_TYPE,
				'post_title'   => sanitize_text_field( $cols['title'] ),
				'post_name'    => $cols['slug'],
				'post_status'  => $status,
				'post_content' => wp_kses_post( $cols['description'] ),
			),
			true
		);
		if ( is_wp_error( $post_id ) ) {
			return $post_id;
		}

		/* Categories — created if missing */
		$cats = array_filter( array_map( 'trim', explode( '|', (string) $cols['categories'] ) ) );
		if ( ! empty( $cats ) ) {
			$term_ids = array();
			foreach ( $cats as $name ) {
				$term = term_exists( $name, AumNexCart_Post_Type::TAXONOMY );
				if ( ! $term ) {
					$term = wp_insert_term( $name, AumNexCart_Post_Type::TAXONOMY );
					if ( is_wp_error( $term ) ) {
						continue;
					}
				}
				$term_ids[] = (int) ( is_array( $term ) ? $term['term_id'] : $term );
			}
			if ( ! empty( $term_ids ) ) {
				wp_set_object_terms( $post_id, $term_ids, AumNexCart_Post_Type::TAXONOMY );
			}
		}

		/* Price */
		AumNexCart_Meta::save_price(
			$post_id,
			array(
				'type'     => $cols['price_type'],
				'min'      => $cols['price_min'],
				'max'      => $cols['price_max'],
				'text'     => $cols['price_text'],
				'currency' => $cols['price_currency'],
			)
		);

		/* Attributes (JSON) */
		$attrs = json_decode( (string) $cols['attributes'], true );
		if ( is_array( $attrs ) ) {
			AumNexCart_Meta::save_attributes( $post_id, $attrs );
		}

		/* Media URLs (remote-only, pipe-separated) */
		$urls = array_filter( array_map( 'trim', explode( '|', (string) $cols['media_urls'] ) ) );
		if ( ! empty( $urls ) ) {
			$items = array();
			foreach ( $urls as $url ) {
				$type    = preg_match( '/\.(mp4|webm|mov|m4v)(\?|$)/i', $url ) ? 'video' : 'image';
				$items[] = array(
					'type'      => $type,
					'source'    => 'remote',
					'url'       => $url,
					'thumb_url' => '',
				);
			}
			AumNexCart_Meta::save_media( $post_id, $items );
		}

		/* Contact (JSON) */
		$contact = json_decode( (string) $cols['contact'], true );
		if ( is_array( $contact ) ) {
			AumNexCart_Meta::save_contact( $post_id, $contact );
		}

		return $post_id;
	}

	/* ================================================================
	 * REINDEX ATTRIBUTES
	 * ================================================================ */

	/**
	 * Rewrites shadow attribute meta for a batch of products. Called
	 * repeatedly by JS until done is reported. The batch position is
	 * passed in via paged param so no server-side state is needed.
	 */
	public function ajax_reindex() {
		check_ajax_referer( self::NONCE_TOOLS, 'nonce' );
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied.', 'aumnexcart' ) ) );
		}

		$paged = isset( $_POST['paged'] ) ? max( 1, absint( $_POST['paged'] ) ) : 1;

		$q = new WP_Query(
			array(
				'post_type'      => AumNexCart_Post_Type::POST_TYPE,
				'post_status'    => 'any',
				'posts_per_page' => self::BATCH_SIZE_REINDEX,
				'paged'          => $paged,
				'fields'         => 'ids',
				'orderby'        => 'ID',
				'order'          => 'ASC',
			)
		);

		foreach ( $q->posts as $post_id ) {
			$rows = AumNexCart_Meta::get_attributes( $post_id );
			AumNexCart_Meta::rebuild_attribute_shadows( $post_id, $rows );
		}

		$total = (int) $q->found_posts;
		$done  = ( $paged * self::BATCH_SIZE_REINDEX ) >= $total;
		$processed = min( $paged * self::BATCH_SIZE_REINDEX, $total );

		if ( $done ) {
			AumNexCart_Filter::invalidate_value_cache();
		}

		wp_send_json_success(
			array(
				'processed' => $processed,
				'total'     => $total,
				'paged'     => $paged,
				'done'      => $done,
			)
		);
	}

	/* ================================================================
	 * UI RENDERING
	 * ================================================================ */

	/**
	 * Renders the Tools tab content. Called from Settings.
	 */
	public static function render_tab() {
		$token = isset( $_GET['import_token'] ) ? sanitize_text_field( wp_unslash( $_GET['import_token'] ) ) : '';
		$err   = isset( $_GET['import_error'] ) ? sanitize_text_field( wp_unslash( $_GET['import_error'] ) ) : '';

		if ( $err ) {
			$messages = array(
				'no_file'    => __( 'No file was uploaded.', 'aumnexcart' ),
				'unreadable' => __( 'Could not read the uploaded file.', 'aumnexcart' ),
				'empty'      => __( 'The CSV file appears to be empty.', 'aumnexcart' ),
				'bad_header' => __( 'The CSV header does not match the expected columns. Export a template first to see the correct format.', 'aumnexcart' ),
			);
			$msg = isset( $messages[ $err ] ) ? $messages[ $err ] : $err;
			echo '<div class="notice notice-error"><p>' . esc_html( $msg ) . '</p></div>';
		}

		$export_url = wp_nonce_url(
			admin_url( 'admin-post.php?action=aumnexcart_export_csv' ),
			self::NONCE_TOOLS
		);
		?>
		<h2><?php esc_html_e( 'Export Products', 'aumnexcart' ); ?></h2>
		<p><?php esc_html_e( 'Download all products as a CSV file. Use this as a template for bulk edits or to back up your catalog.', 'aumnexcart' ); ?></p>
		<p><a class="button" href="<?php echo esc_url( $export_url ); ?>"><?php esc_html_e( 'Download CSV', 'aumnexcart' ); ?></a></p>

		<hr>

		<h2><?php esc_html_e( 'Import Products', 'aumnexcart' ); ?></h2>
		<p><?php esc_html_e( 'Upload a CSV with the same column headers as the export. New products are created; existing ones are not touched. Media URLs must be remote (no local uploads).', 'aumnexcart' ); ?></p>

		<?php if ( $token ) : ?>
			<div id="aumnexcart-import-runner" data-token="<?php echo esc_attr( $token ); ?>" data-nonce="<?php echo esc_attr( wp_create_nonce( self::NONCE_TOOLS ) ); ?>">
				<p><?php esc_html_e( 'Importing…', 'aumnexcart' ); ?></p>
				<div class="aumnexcart-progress-bar"><div class="aumnexcart-progress-fill" style="width:0%"></div></div>
				<p class="aumnexcart-progress-text">0 / 0</p>
				<div class="aumnexcart-import-report" style="display:none;"></div>
			</div>
		<?php else : ?>
			<form method="post" enctype="multipart/form-data" action="<?php echo esc_url( admin_url( 'admin-post.php' ) ); ?>">
				<?php wp_nonce_field( self::NONCE_TOOLS ); ?>
				<input type="hidden" name="action" value="aumnexcart_import_upload">
				<p><input type="file" name="aumnexcart_csv" accept=".csv" required></p>
				<p><button type="submit" class="button button-primary"><?php esc_html_e( 'Upload and Start Import', 'aumnexcart' ); ?></button></p>
			</form>
		<?php endif; ?>

		<hr>

		<h2><?php esc_html_e( 'Rebuild Attribute Filter Index', 'aumnexcart' ); ?></h2>
		<p><?php esc_html_e( 'Run this after changing the filterable attribute keys in Settings > Filter, or if attribute filters are returning incorrect results. It rewrites the shadow meta rows used by filters.', 'aumnexcart' ); ?></p>
		<div id="aumnexcart-reindex-runner" data-nonce="<?php echo esc_attr( wp_create_nonce( self::NONCE_TOOLS ) ); ?>">
			<p><button type="button" class="button" id="aumnexcart-reindex-start"><?php esc_html_e( 'Rebuild Now', 'aumnexcart' ); ?></button></p>
			<div class="aumnexcart-progress-wrap" style="display:none;">
				<div class="aumnexcart-progress-bar"><div class="aumnexcart-progress-fill" style="width:0%"></div></div>
				<p class="aumnexcart-progress-text">0 / 0</p>
			</div>
		</div>
		<?php
	}

	/* ================================================================
	 * INTERNAL HELPERS
	 * ================================================================ */

	private static function redirect_tools( $args = array() ) {
		wp_safe_redirect( AumNexCart_Settings::page_url( 'tools', $args ) );
		exit;
	}
}