<?php
/**
 * Builds the advert (a marketplace-neutral Listing) for one WooCommerce product or variation, with
 * errors that block publishing and warnings. Pure PHP: the caller supplies the product data.
 *
 * @package Tidelist
 */

namespace Tidelist\Build;

use Tidelist\Channel\CategoryIndex;
use Tidelist\Channel\ChannelInterface;
use Tidelist\Channel\Limits;
use Tidelist\Channel\Listing;
use Tidelist\Mapping\AttributeMap;
use Tidelist\Mapping\AttributeResolver;
use Tidelist\Media\PhotoPaths;
use Tidelist\Support\Text;

/**
 * Listing builder.
 */
final class ListingBuilder {

	const DEFAULT_TITLE       = '{product_name} – {attribute_summary}';
	const DEFAULT_DESCRIPTION = "{description}\n\n{attributes_table}\n\n{shop_footer}";

	/**
	 * Marketplace the advert is for.
	 *
	 * @var ChannelInterface
	 */
	private $channel;

	/**
	 * Limits of the marketplace.
	 *
	 * @var Limits
	 */
	private $limits;

	/**
	 * Settings.
	 *
	 * @var array
	 */
	private $settings;

	/**
	 * Categories of the marketplace.
	 *
	 * @var CategoryIndex
	 */
	private $tree;

	/**
	 * Attribute rules.
	 *
	 * @var AttributeMap
	 */
	private $attribute_map;

	/**
	 * Final say on the price: callable( float $price, array $item, int $category_id ): float, or null.
	 *
	 * @var callable|null
	 */
	private $price_filter;

	/**
	 * Constructor.
	 *
	 * @param ChannelInterface $channel       Marketplace the advert is for (limits, categories, currency, price rule).
	 * @param array            $settings      Plugin settings.
	 * @param AttributeMap     $attribute_map Attribute rules.
	 * @param callable|null    $price_filter  Final say on the price (the Pro add-on's price rules), or null.
	 */
	public function __construct( ChannelInterface $channel, array $settings, AttributeMap $attribute_map, ?callable $price_filter = null ) {
		$this->channel       = $channel;
		$this->limits        = $channel->limits();
		$this->tree          = $channel->taxonomy()->index();
		$this->settings      = $settings;
		$this->attribute_map = $attribute_map;
		$this->price_filter  = $price_filter;
	}

	/**
	 * Builds the advert.
	 *
	 * @param array    $item   Product data: product_id, variation_id, product_name, sku, description_html, short_description_html,
	 *                         price (shop currency), images (upload-relative paths, in order), attribute_summary (list of texts),
	 *                         attribute_table (label => text), remote_category (marketplace category ID, int or null), ask (attribute code => value).
	 * @param callable $values callable( AttributeRule $rule ): string[] — the product's values for an attribute rule.
	 */
	public function build( array $item, callable $values ): BuildResult {
		$result   = new BuildResult();
		$label    = $this->channel->label();
		$category = (int) ( $item['remote_category'] ?? 0 );
		if ( ! $category ) {
			$result->error( 'no_category', Text::channel( 'Not mapped: this product\'s shop category has no {channel} category. Set it in the category mapping.', $label ) );
		} elseif ( $this->tree->count() > 0 && ! $this->tree->has( $category ) ) {
			$result->error( 'no_category', Text::channel( 'The mapped {channel} category does not exist (any more). Choose another one in the category mapping.', $label ) );
		} elseif ( $this->tree->count() > 0 && ! $this->tree->is_leaf( $category ) ) {
			$result->error( 'category_not_leaf', Text::channel( '{channel} only takes adverts in the last level of its categories. Choose a more specific category.', $label ) );
		}

		$others = array_values( array_filter( array_map( 'intval', (array) ( $item['category_alternatives'] ?? array() ) ) ) );
		if ( $category && $others ) {
			$name = function ( int $id ): string {
				return $this->tree->has( $id ) ? $this->tree->path( $id ) : '#' . $id;
			};
			$result->warn(
				'category_ambiguous',
				Text::channel( 'The shop categories of this product lead to more than one {channel} category, so one was picked. Check that it is the right one.', $label ),
				array( $name( $category ), implode( '; ', array_map( $name, $others ) ) )
			);
		}

		$block = (string) ( $item['listing_block'] ?? '' );
		if ( 'out_of_stock' === $block ) {
			$result->error( 'out_of_stock', 'This product is out of stock, so it cannot be advertised. Put it back in stock in the shop first.' );
		} elseif ( '' !== $block ) {
			$result->error( 'not_for_sale', 'This product is not published in the shop, so it cannot be advertised.' );
		}

		$title       = $this->title( $item, $result );
		$description = $this->description( $item, $result );

		// Price.
		$currency   = $this->channel->currency();
		$shop_price = $this->channel->convert_price( (float) ( $item['price'] ?? 0 ) );
		$price      = $this->channel->adjust_price( $shop_price, $category );
		if ( null !== $this->price_filter ) {
			$price = (float) call_user_func( $this->price_filter, $price, $item, $category );
		}
		if ( $price <= 0 ) {
			$result->error( 'no_price', 'The product has no price.' );
		}

		// Photos.
		$limit  = $category && $this->tree->photos_limit( $category ) > 0 ? $this->tree->photos_limit( $category ) : $this->limits->photos_default;
		$images = $this->images( (array) ( $item['images'] ?? array() ), $limit, $result );
		if ( ! empty( $item['images_from_parent'] ) && $images ) {
			$result->warn( 'photos_from_parent', 'This variation has no own photos; the product photos may show other options.' );
		}

		// Contact.
		$contact = array( 'name' => trim( (string) ( $this->settings['contact_name'] ?? '' ) ) );
		$phone   = preg_replace( '/[^\d+]/', '', (string) ( $this->settings['contact_phone'] ?? '' ) );
		if ( '' !== $phone ) {
			$contact['phone'] = $phone;
		}
		if ( '' === $contact['name'] ) {
			$result->error( 'no_contact', 'Contact name is not set (Settings → Advert contact).' );
		}

		// Attributes.
		$attributes  = array();
		$definitions = array();
		if ( $category ) {
			$definitions = (array) $this->channel->taxonomy()->attributes( $category );
			if ( ! $definitions ) {
				$result->warn( 'no_attribute_data', Text::channel( 'The attributes of this {channel} category could not be read, so none are sent. Connect {channel} and try again.', $label ) );
			}
			$resolved   = AttributeResolver::resolve( $definitions, $this->attribute_map->rules_for( $category ), $values, (array) ( $item['ask'] ?? array() ), $this->channel->managed_attributes(), $label );
			$attributes = $resolved['attributes'];
			foreach ( $resolved['errors'] as $error ) {
				$result->error( $error['code'], $error['text'], (array) ( $error['args'] ?? array() ) );
			}
			foreach ( $resolved['warnings'] as $warning ) {
				$result->warn( $warning['code'], $warning['text'], (array) ( $warning['args'] ?? array() ) );
			}
		}

		$listing = new Listing(
			array(
				'title'       => $title,
				'description' => $description,
				'price'       => $price,
				'currency'    => $currency,
				'category_id' => (string) $category,
				'attributes'  => $attributes,
				'images'      => array_column( $images, 'url' ),
				'contact'     => $contact,
				'external_id' => (string) ( ! empty( $item['variation_id'] ) ? (int) $item['variation_id'] : (int) ( $item['product_id'] ?? 0 ) ),
			)
		);
		$this->channel->complete_listing( $listing, $result, $definitions );
		$result->listing = $listing;
		$result->info    = array(
			'category'   => $category && $this->tree->has( $category ) ? $this->tree->path( $category ) : ( $category ? '#' . $category : '' ),
			'shop_price' => (string) $shop_price,
			'currency'   => $currency,
			'converted'  => (string) ( $result->info['converted'] ?? '' ),
		);
		return $result;
	}

	/**
	 * Advert title from the template, cleaned and cut to the marketplace's length.
	 *
	 * @param array       $item   Product data.
	 * @param BuildResult $result Result (for errors).
	 */
	private function title( array $item, BuildResult $result ): string {
		$template               = trim( (string) ( $this->settings['title_template'] ?? '' ) );
		$template               = '' !== $template ? $template : self::DEFAULT_TITLE;
		$values                 = array(
			'product_name'      => '',
			'attribute_summary' => implode( ', ', array_map( 'strval', (array) ( $item['attribute_summary'] ?? array() ) ) ),
			'sku'               => (string) ( $item['sku'] ?? '' ),
		);
		$name                   = TextRules::clean( trim( (string) ( $item['product_name'] ?? '' ) ), $this->limits->forbids_contacts );
		$probe                  = Template::render( $template, array_merge( $values, array( 'product_name' => 'X' ) ) );
		$room                   = $this->limits->title_max - ( TextRules::length( $probe ) - 1 );
		$values['product_name'] = TextRules::shorten( $name, max( 20, $room ) );
		$title                  = $this->tidy_title( Template::render( $template, $values ) );
		if ( TextRules::length( $title ) > $this->limits->title_max ) {
			$title = TextRules::shorten( $title, $this->limits->title_max );
		}
		$length = TextRules::length( $title );
		if ( $length < $this->limits->title_min || $length > $this->limits->title_max ) {
			$result->error( 'title_length', sprintf( 'Title must be %1$d–%2$d characters (now %3$d). Use a longer product name or add attributes to the title template.', $this->limits->title_min, $this->limits->title_max, $length ) );
		}
		return $title;
	}

	/**
	 * Removes dangling separators left by empty placeholders ("Shirt – ").
	 *
	 * @param string $title Title.
	 */
	private function tidy_title( string $title ): string {
		$title = (string) preg_replace( '/\s+/u', ' ', $title );
		$title = (string) preg_replace( '/(\s[-–—:|,]\s*)+$/u', '', $title );
		$title = (string) preg_replace( '/^(\s*[-–—:|,]\s)+/u', '', $title );
		return trim( $title );
	}

	/**
	 * Advert description from the template (plain text, no contact details).
	 *
	 * @param array       $item   Product data.
	 * @param BuildResult $result Result.
	 */
	private function description( array $item, BuildResult $result ): string {
		$template = trim( (string) ( $this->settings['description_template'] ?? '' ) );
		$template = '' !== $template ? $template : self::DEFAULT_DESCRIPTION;

		$raw         = TextRules::html_to_text( (string) ( $item['description_html'] ?? '' ) );
		$description = TextRules::clean( $raw, $this->limits->forbids_contacts );
		if ( $this->limits->forbids_contacts && TextRules::has_contacts( $raw ) ) {
			$result->warn( 'contacts_removed', Text::channel( 'A web address, e-mail or phone number was removed from the product text ({channel} does not allow them).', $this->channel->label() ) );
		}
		$short = TextRules::clean( TextRules::html_to_text( (string) ( $item['short_description_html'] ?? '' ) ), $this->limits->forbids_contacts );
		$table = array();
		foreach ( (array) ( $item['attribute_table'] ?? array() ) as $label => $text ) {
			if ( '' !== trim( (string) $text ) ) {
				$table[] = trim( (string) $label ) . ': ' . trim( (string) $text );
			}
		}
		$footer = TextRules::clean( (string) ( $this->settings['shop_footer'] ?? '' ), $this->limits->forbids_contacts );

		$values = array(
			'description'       => '',
			'short_description' => $short,
			'attributes_table'  => implode( "\n", $table ),
			'measurements'      => trim( (string) ( $item['measurements'] ?? '' ) ), // Filled by the Pro add-on (filter tidelist_measurements).
			'shop_footer'       => $footer,
			'product_name'      => (string) ( $item['product_name'] ?? '' ),
			'sku'               => (string) ( $item['sku'] ?? '' ),
		);
		if ( '' === $description && '' !== $short && false === strpos( $template, '{short_description}' ) ) {
			$description = $short;
		}
		$base                  = $this->tidy_text( Template::render( $template, $values ) );
		$room                  = $this->limits->description_max - TextRules::length( $base ) - 2;
		$values['description'] = TextRules::shorten( $description, max( 0, $room ) );
		$text                  = $this->tidy_text( Template::render( $template, $values ) );

		$length = TextRules::length( $text );
		if ( $length < $this->limits->description_min || $length > $this->limits->description_max ) {
			$result->error( 'description_length', sprintf( 'Description must be %1$d–%2$d characters (now %3$d). Add product text or a footer text in the settings.', $this->limits->description_min, $this->limits->description_max, $length ) );
		}
		return $text;
	}

	/**
	 * Collapses the empty lines left by empty placeholders.
	 *
	 * @param string $text Text.
	 */
	private function tidy_text( string $text ): string {
		$text = (string) preg_replace( '/[ \t]+\n/u', "\n", $text );
		$text = (string) preg_replace( '/\n{3,}/u', "\n\n", $text );
		return trim( $text );
	}

	/**
	 * Photo list: [{"url": "..."}], deduplicated and limited to the category limit.
	 *
	 * @param array       $paths  Upload-relative file paths.
	 * @param int         $limit  Category photo limit.
	 * @param BuildResult $result Result.
	 */
	private function images( array $paths, int $limit, BuildResult $result ): array {
		$base  = (string) ( $this->settings['image_base_url'] ?? '' );
		$paths = array_values( array_unique( array_filter( array_map( 'strval', $paths ) ) ) );
		if ( ! $paths ) {
			$result->error( 'no_photos', 'The product has no photos.' );
			return array();
		}
		if ( count( $paths ) > $limit ) {
			$result->warn( 'photos_trimmed', sprintf( 'Only the first %1$d of %2$d photos are used (%3$s limit).', $limit, count( $paths ), $this->channel->label() ) );
			$paths = array_slice( $paths, 0, $limit );
		}
		// Photos a marketplace cannot take as they are (for example .webp) are sent as a JPG copy that the plugin makes.
		$converted = array();
		foreach ( $paths as $path ) {
			if ( ! PhotoPaths::is_native( $path ) ) {
				$converted[] = $path;
			}
		}
		$result->info['converted'] = implode( "\n", $converted );
		return array_map(
			static function ( $path ) use ( $base ) {
				return array( 'url' => PhotoPaths::url( $base, $path ) );
			},
			$paths
		);
	}
}