<?php

declare( strict_types=1 );

namespace AcezSeo\Import;

use AcezSeo\Data\PostMetaRepositoryInterface;
use AcezSeo\Data\TermMetaRepositoryInterface;

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

/**
 * Shared plumbing for importers: the "fill empty only unless overwrite"
 * write policy, and helpers for turning source image URLs into attachment IDs.
 */
abstract class BaseSeoImporter implements SeoImporterInterface
{
	protected PostMetaRepositoryInterface $post_meta;
	protected TermMetaRepositoryInterface $term_meta;

	public function __construct( PostMetaRepositoryInterface $post_meta, TermMetaRepositoryInterface $term_meta )
	{
		$this->post_meta = $post_meta;
		$this->term_meta = $term_meta;
	}

	public function preview( bool $overwrite ): ImportReport
	{
		$report          = $this->run( true, $overwrite );
		$report->dry_run = true;

		return $report;
	}

	public function import( bool $overwrite ): ImportReport
	{
		return $this->run( false, $overwrite );
	}

	abstract protected function run( bool $dry, bool $overwrite ): ImportReport;

	/**
	 * Imports one string field into post meta. Empty source values are
	 * ignored entirely (not even counted); a non-empty existing target value
	 * is only replaced when $overwrite is set.
	 */
	protected function import_post_field( ImportReport $report, bool $dry, bool $overwrite, int $post_id, string $target_key, string $value ): void
	{
		$value = trim( $value );

		if ( '' === $value )
		{
			return;
		}

		$existing = (string) $this->post_meta->get( $post_id, $target_key );

		if ( '' !== $existing && ! $overwrite )
		{
			++$report->skipped_fields;

			return;
		}

		if ( ! $dry )
		{
			$this->post_meta->update( $post_id, $target_key, $value );
		}

		++$report->imported_fields;
		$report->add_post_field( $post_id, $target_key, $value );
	}

	/**
	 * Imports one boolean flag (robots index/follow) into post meta. Unlike
	 * string fields, "already set" means the meta row EXISTS — a stored
	 * `false` is a deliberate choice that must not be overwritten silently.
	 */
	protected function import_post_flag( ImportReport $report, bool $dry, bool $overwrite, int $post_id, string $target_key, bool $value ): void
	{
		if ( $this->post_meta->has( $post_id, $target_key ) && ! $overwrite )
		{
			++$report->skipped_fields;

			return;
		}

		if ( ! $dry )
		{
			$this->post_meta->update( $post_id, $target_key, $value );
		}

		++$report->imported_fields;
		$report->add_post_field( $post_id, $target_key, $value ? __( 'yes', 'acez-seo' ) : __( 'no', 'acez-seo' ) );
	}

	protected function import_term_field( ImportReport $report, bool $dry, bool $overwrite, int $term_id, string $target_key, string $value ): void
	{
		$value = trim( $value );

		if ( '' === $value )
		{
			return;
		}

		$existing = (string) $this->term_meta->get( $term_id, $target_key );

		if ( '' !== $existing && ! $overwrite )
		{
			++$report->skipped_fields;

			return;
		}

		if ( ! $dry )
		{
			$this->term_meta->update( $term_id, $target_key, $value );
		}

		++$report->imported_fields;
		$report->add_term_field( $term_id, $target_key, $value );
	}

	/**
	 * Source plugins mostly store OG images as URLs; we store an attachment
	 * ID. Returns 0 when the URL doesn't belong to this site's media library
	 * (external images can't be mapped — skipped rather than guessed).
	 */
	protected function attachment_id_from_url( string $url ): int
	{
		if ( '' === trim( $url ) )
		{
			return 0;
		}

		return (int) attachment_url_to_postid( $url );
	}

	protected function import_post_og_image( ImportReport $report, bool $dry, bool $overwrite, int $post_id, int $attachment_id ): void
	{
		if ( $attachment_id <= 0 )
		{
			return;
		}

		$existing = (int) $this->post_meta->get( $post_id, \AcezSeo\Data\MetaFields::OG_IMAGE_ID );

		if ( $existing > 0 && ! $overwrite )
		{
			++$report->skipped_fields;

			return;
		}

		if ( ! $dry )
		{
			$this->post_meta->update( $post_id, \AcezSeo\Data\MetaFields::OG_IMAGE_ID, $attachment_id );
		}

		++$report->imported_fields;

		$image_title = (string) get_the_title( $attachment_id );
		$report->add_post_field( $post_id, \AcezSeo\Data\MetaFields::OG_IMAGE_ID, '' !== $image_title ? $image_title : sprintf( '#%d', $attachment_id ) );
	}
}