<?php
/**
 * FAQ import / export (CSV + JSON).
 *
 * @package AccordionFaq
 */

namespace AccordionFaq\Admin;

defined( 'ABSPATH' ) || exit;

use AccordionFaq\Setup\PostType;
use AccordionFaq\Setup\Taxonomy;

/**
 * Class ImportExport
 */
class ImportExport {

	/**
	 * Register hooks.
	 *
	 * @return void
	 */
	public function register() {
		add_action( 'admin_post_accordion_faq_export', array( $this, 'export' ) );
		add_action( 'admin_post_accordion_faq_import', array( $this, 'import' ) );
	}

	/**
	 * Export all FAQs.
	 *
	 * @return void
	 */
	public function export() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Permission denied.', 'accordion-faq-plugin' ) );
		}
		check_admin_referer( 'accordion_faq_export' );

		$format = isset( $_GET['format'] ) ? sanitize_key( wp_unslash( $_GET['format'] ) ) : 'csv';

		$faqs = get_posts(
			array(
				'post_type'      => PostType::POST_TYPE,
				'post_status'    => 'any',
				'posts_per_page' => -1,
			)
		);

		$rows = array();
		foreach ( $faqs as $faq ) {
			$cats   = wp_get_post_terms( $faq->ID, Taxonomy::TAXONOMY, array( 'fields' => 'names' ) );
			$rows[] = array(
				'question'   => $faq->post_title,
				'answer'     => $faq->post_content,
				'categories' => is_wp_error( $cats ) ? '' : implode( '|', $cats ),
				'status'     => $faq->post_status,
			);
		}

		if ( 'json' === $format ) {
			header( 'Content-Type: application/json; charset=utf-8' );
			header( 'Content-Disposition: attachment; filename=faqs-' . gmdate( 'Y-m-d' ) . '.json' );
			echo wp_json_encode( $rows, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES );
			exit;
		}

		header( 'Content-Type: text/csv; charset=utf-8' );
		header( 'Content-Disposition: attachment; filename=faqs-' . gmdate( 'Y-m-d' ) . '.csv' );
		$out = fopen( 'php://output', 'w' );
		fputcsv( $out, array( 'question', 'answer', 'categories', 'status' ) );
		foreach ( $rows as $row ) {
			fputcsv( $out, $row );
		}
		fclose( $out ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_fclose
		exit;
	}

	/**
	 * Import FAQs from an uploaded CSV or JSON file.
	 *
	 * @return void
	 */
	public function import() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Permission denied.', 'accordion-faq-plugin' ) );
		}
		check_admin_referer( 'accordion_faq_import' );

		$redirect = admin_url( 'admin.php?page=' . Menu::SLUG . '-tools' );

		if ( empty( $_FILES['afaq_file']['tmp_name'] ) ) {
			wp_safe_redirect( add_query_arg( 'afaq_import', 'nofile', $redirect ) );
			exit;
		}

		$tmp  = sanitize_text_field( wp_unslash( $_FILES['afaq_file']['tmp_name'] ) );
		$name = isset( $_FILES['afaq_file']['name'] ) ? sanitize_file_name( wp_unslash( $_FILES['afaq_file']['name'] ) ) : '';
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
		$contents = file_get_contents( $tmp );
		$imported = 0;

		$rows = array();
		if ( preg_match( '/\.json$/i', $name ) ) {
			$decoded = json_decode( $contents, true );
			$rows    = is_array( $decoded ) ? $decoded : array();
		} else {
			$lines  = preg_split( '/\r\n|\r|\n/', (string) $contents );
			$header = null;
			foreach ( $lines as $line ) {
				if ( '' === trim( $line ) ) {
					continue;
				}
				$cols = str_getcsv( $line );
				if ( null === $header ) {
					$header = array_map( 'strtolower', array_map( 'trim', $cols ) );
					continue;
				}
				$rows[] = array_combine( $header, array_pad( $cols, count( $header ), '' ) );
			}
		}

		$allowed_status = array( 'publish', 'draft', 'pending', 'private' );

		foreach ( $rows as $row ) {
			$question = isset( $row['question'] ) ? sanitize_text_field( $row['question'] ) : '';
			if ( '' === $question ) {
				continue;
			}
			// Respect an exported status column; fall back to publish.
			$status = isset( $row['status'] ) ? sanitize_key( $row['status'] ) : 'publish';
			if ( ! in_array( $status, $allowed_status, true ) ) {
				$status = 'publish';
			}
			$post_id = wp_insert_post(
				array(
					'post_type'    => PostType::POST_TYPE,
					'post_status'  => $status,
					'post_title'   => $question,
					'post_content' => isset( $row['answer'] ) ? wp_kses_post( $row['answer'] ) : '',
				)
			);
			if ( $post_id && ! is_wp_error( $post_id ) ) {
				if ( ! empty( $row['categories'] ) ) {
					$names = array_filter( array_map( 'trim', explode( '|', (string) $row['categories'] ) ) );
					wp_set_object_terms( $post_id, $names, Taxonomy::TAXONOMY );
				}
				$imported++;
			}
		}

		wp_safe_redirect( add_query_arg( 'afaq_import', $imported, $redirect ) );
		exit;
	}
}