<?php
/**
 * Meta read/write helper.
 *
 * Centralizes all meta access so JSON encoding rules, sanitization,
 * default values, and the attributes "shadow meta" pattern are
 * defined in exactly one place. Other classes (meta boxes, frontend
 * hooks, REST handlers, migration tool) call these helpers rather
 * than touching get_post_meta directly.
 *
 * Shadow meta pattern (used by attributes):
 *   _aumnexcart_attributes   : JSON of [{ key, value }] (full canonical data)
 *   _aumnexcart_attr_{slug}  : flat string per filterable key
 *
 * The shadow rows are rewritten on every save based on the
 * "filterable_attributes" setting, so adding/removing a key from
 * the filter list takes effect on the next save (or via bulk
 * re-index, planned in Pack C).
 */

defined( 'ABSPATH' ) || exit;

class AumNexCart_Meta {

	const KEY_MEDIA          = '_aumnexcart_media';
	const KEY_PRICE_TYPE     = '_aumnexcart_price_type';
	const KEY_PRICE_MIN      = '_aumnexcart_price_min';
	const KEY_PRICE_MAX      = '_aumnexcart_price_max';
	const KEY_PRICE_CURRENCY = '_aumnexcart_price_currency';
	const KEY_PRICE_TEXT     = '_aumnexcart_price_text';
	const KEY_ATTRIBUTES     = '_aumnexcart_attributes';
	const KEY_CONTACT        = '_aumnexcart_contact';
	const KEY_ATTR_SHADOW_PREFIX = '_aumnexcart_attr_';

	/* ----------------------------------------------------------------
	 * Media
	 * ---------------------------------------------------------------- */

	/**
	 * Returns the media list for a product as a clean array of items.
	 * Each item has: type (image|video), source (upload|remote),
	 * url, thumb_url, attachment_id (only for uploads).
	 *
	 * @param int $post_id
	 * @return array
	 */
	public static function get_media( $post_id ) {
		$raw = get_post_meta( $post_id, self::KEY_MEDIA, true );
		if ( empty( $raw ) ) {
			return array();
		}
		$decoded = is_array( $raw ) ? $raw : json_decode( $raw, true );
		if ( ! is_array( $decoded ) ) {
			return array();
		}
		$clean = array();
		foreach ( $decoded as $item ) {
			if ( ! is_array( $item ) ) {
				continue;
			}
			/*
			 * ⚠️ 只给了 attachment_id、没给 url 的行**也算数**。
			 *
			 * 原来这里是 `empty($item['url']) -> continue`，于是一行"只知道附件 ID"
			 * 的媒体被静默丢掉。两个地方会踩到：
			 *   · 模板包（kit）里只能写附件引用，**写不出 URL** —— 包在导入之前
			 *     根本不知道买家站的域名是什么；
			 *   · 站点换域名之后，存下来的绝对 URL 全部失效，而 ID 不会。
			 * 存 ID 比存 URL 更对，所以这里补一条：url 为空就从 ID 现算。
			 */
			if ( empty( $item['url'] ) && ! empty( $item['attachment_id'] ) ) {
				$derived = wp_get_attachment_url( absint( $item['attachment_id'] ) );
				if ( $derived ) {
					$item['url'] = $derived;
				}
			}
			if ( empty( $item['url'] ) ) {
				continue;
			}
			$clean[] = array(
				'type'          => isset( $item['type'] ) && 'video' === $item['type'] ? 'video' : 'image',
				'source'        => isset( $item['source'] ) && 'remote' === $item['source'] ? 'remote' : 'upload',
				'url'           => esc_url_raw( $item['url'] ),
				'thumb_url'     => isset( $item['thumb_url'] ) ? esc_url_raw( $item['thumb_url'] ) : '',
				'attachment_id' => isset( $item['attachment_id'] ) ? absint( $item['attachment_id'] ) : 0,
			);
		}
		return $clean;
	}

	/**
	 * Persists the media list. Empty input clears the meta row.
	 *
	 * @param int   $post_id
	 * @param array $items
	 */
	public static function save_media( $post_id, $items ) {
		if ( ! is_array( $items ) ) {
			$items = array();
		}
		$sanitized = array();
		foreach ( $items as $item ) {
			if ( ! is_array( $item ) || empty( $item['url'] ) ) {
				continue;
			}
			$url = esc_url_raw( $item['url'] );
			if ( ! $url ) {
				continue;
			}
			$sanitized[] = array(
				'type'          => isset( $item['type'] ) && 'video' === $item['type'] ? 'video' : 'image',
				'source'        => isset( $item['source'] ) && 'remote' === $item['source'] ? 'remote' : 'upload',
				'url'           => $url,
				'thumb_url'     => isset( $item['thumb_url'] ) ? esc_url_raw( $item['thumb_url'] ) : '',
				'attachment_id' => isset( $item['attachment_id'] ) ? absint( $item['attachment_id'] ) : 0,
			);
		}
		if ( empty( $sanitized ) ) {
			delete_post_meta( $post_id, self::KEY_MEDIA );
		} else {
			update_post_meta( $post_id, self::KEY_MEDIA, wp_json_encode( $sanitized, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES ) );
		}
	}

	/* ----------------------------------------------------------------
	 * Price
	 * ---------------------------------------------------------------- */

	/**
	 * Returns the price block as a normalized array.
	 *
	 * @param int $post_id
	 * @return array { type, min, max, currency, text }
	 */
	public static function get_price( $post_id ) {
		$type = get_post_meta( $post_id, self::KEY_PRICE_TYPE, true );
		if ( ! in_array( $type, array( 'range', 'text', 'hidden' ), true ) ) {
			$type = 'hidden';
		}
		return array(
			'type'     => $type,
			'min'      => get_post_meta( $post_id, self::KEY_PRICE_MIN, true ),
			'max'      => get_post_meta( $post_id, self::KEY_PRICE_MAX, true ),
			'currency' => get_post_meta( $post_id, self::KEY_PRICE_CURRENCY, true ),
			'text'     => get_post_meta( $post_id, self::KEY_PRICE_TEXT, true ),
		);
	}

	/**
	 * Persists the price block. Unused fields for the chosen mode
	 * are cleared to keep the meta table tidy.
	 *
	 * @param int   $post_id
	 * @param array $data { type, min, max, currency, text }
	 */
	public static function save_price( $post_id, $data ) {
		$type = isset( $data['type'] ) && in_array( $data['type'], array( 'range', 'text', 'hidden' ), true )
			? $data['type']
			: 'hidden';

		update_post_meta( $post_id, self::KEY_PRICE_TYPE, $type );

		if ( 'range' === $type ) {
			$min = isset( $data['min'] ) && '' !== $data['min'] ? (float) $data['min'] : '';
			$max = isset( $data['max'] ) && '' !== $data['max'] ? (float) $data['max'] : '';
			update_post_meta( $post_id, self::KEY_PRICE_MIN, $min );
			update_post_meta( $post_id, self::KEY_PRICE_MAX, $max );
			delete_post_meta( $post_id, self::KEY_PRICE_TEXT );
		} elseif ( 'text' === $type ) {
			update_post_meta( $post_id, self::KEY_PRICE_TEXT, isset( $data['text'] ) ? sanitize_text_field( $data['text'] ) : '' );
			delete_post_meta( $post_id, self::KEY_PRICE_MIN );
			delete_post_meta( $post_id, self::KEY_PRICE_MAX );
		} else {
			delete_post_meta( $post_id, self::KEY_PRICE_MIN );
			delete_post_meta( $post_id, self::KEY_PRICE_MAX );
			delete_post_meta( $post_id, self::KEY_PRICE_TEXT );
		}

		if ( isset( $data['currency'] ) && '' !== $data['currency'] ) {
			update_post_meta( $post_id, self::KEY_PRICE_CURRENCY, sanitize_text_field( $data['currency'] ) );
		} else {
			delete_post_meta( $post_id, self::KEY_PRICE_CURRENCY );
		}
	}

	/* ----------------------------------------------------------------
	 * Attributes (with shadow meta for filtering)
	 * ---------------------------------------------------------------- */

	/**
	 * Returns the attributes list.
	 *
	 * @param int $post_id
	 * @return array of [ { key, value } ]
	 */
	public static function get_attributes( $post_id ) {
		$raw = get_post_meta( $post_id, self::KEY_ATTRIBUTES, true );
		if ( empty( $raw ) ) {
			return array();
		}
		$decoded = is_array( $raw ) ? $raw : json_decode( $raw, true );
		if ( ! is_array( $decoded ) ) {
			return array();
		}
		$clean = array();
		foreach ( $decoded as $row ) {
			if ( ! is_array( $row ) ) {
				continue;
			}
			$k = isset( $row['key'] ) ? trim( (string) $row['key'] ) : '';
			$v = isset( $row['value'] ) ? trim( (string) $row['value'] ) : '';
			if ( '' === $k && '' === $v ) {
				continue;
			}
			$clean[] = array( 'key' => $k, 'value' => $v );
		}
		return $clean;
	}

	/**
	 * Persists attributes AND rewrites shadow meta rows for any keys
	 * configured as filterable. Always wipes the previous shadow set
	 * for this post first to avoid stale entries when keys are
	 * renamed or removed.
	 *
	 * @param int   $post_id
	 * @param array $rows of [ { key, value } ]
	 */
	public static function save_attributes( $post_id, $rows ) {
		if ( ! is_array( $rows ) ) {
			$rows = array();
		}
		$sanitized = array();
		foreach ( $rows as $row ) {
			if ( ! is_array( $row ) ) {
				continue;
			}
			$k = isset( $row['key'] ) ? sanitize_text_field( $row['key'] ) : '';
			$v = isset( $row['value'] ) ? sanitize_text_field( $row['value'] ) : '';
			if ( '' === $k && '' === $v ) {
				continue;
			}
			$sanitized[] = array( 'key' => $k, 'value' => $v );
		}

		if ( empty( $sanitized ) ) {
			delete_post_meta( $post_id, self::KEY_ATTRIBUTES );
		} else {
			update_post_meta( $post_id, self::KEY_ATTRIBUTES, wp_json_encode( $sanitized, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES ) );
		}

		self::rebuild_attribute_shadows( $post_id, $sanitized );
	}

	/**
	 * Rebuilds the flat shadow meta rows used for fast filtering on
	 * archive queries. Called on save and also exposed publicly so
	 * a future bulk re-index command can rebuild without saving.
	 *
	 * @param int   $post_id
	 * @param array $rows Pre-sanitized rows.
	 */
	public static function rebuild_attribute_shadows( $post_id, $rows ) {
		global $wpdb;

		$wpdb->query(
			$wpdb->prepare(
				"DELETE FROM {$wpdb->postmeta} WHERE post_id = %d AND meta_key LIKE %s",
				$post_id,
				$wpdb->esc_like( self::KEY_ATTR_SHADOW_PREFIX ) . '%'
			)
		);

		$settings   = AumNexCart_Settings::get_all();
		$filterable = isset( $settings['filterable_attributes'] ) && is_array( $settings['filterable_attributes'] )
			? array_map( 'strtolower', $settings['filterable_attributes'] )
			: array();

		if ( empty( $filterable ) || empty( $rows ) ) {
			return;
		}

		foreach ( $rows as $row ) {
			$slug = self::attribute_key_to_slug( $row['key'] );
			if ( '' === $slug ) {
				continue;
			}
			if ( ! in_array( strtolower( $row['key'] ), $filterable, true ) ) {
				continue;
			}
			add_post_meta( $post_id, self::KEY_ATTR_SHADOW_PREFIX . $slug, $row['value'] );
		}
	}

	/**
	 * Normalizes a user-entered attribute label into a URL-safe slug
	 * suitable for use as a meta key suffix. Returns '' if nothing
	 * usable remains.
	 *
	 * @param string $key
	 * @return string
	 */
	public static function attribute_key_to_slug( $key ) {
		$slug = sanitize_title( $key );
		return $slug ? $slug : '';
	}

	/* ----------------------------------------------------------------
	 * Contact actions
	 * ---------------------------------------------------------------- */

	const ALLOWED_CONTACT_TYPES = array( 'email', 'whatsapp', 'custom' );

	/**
	 * Returns contact actions normalized into [ { type, label, value, href } ].
	 * The href is rendered server-side so templates don't need to know
	 * the per-type formatting (mailto:, wa.me, etc).
	 *
	 * @param int $post_id
	 * @return array
	 */
	public static function get_contact( $post_id ) {
		$raw = get_post_meta( $post_id, self::KEY_CONTACT, true );
		if ( empty( $raw ) ) {
			return array();
		}
		$decoded = is_array( $raw ) ? $raw : json_decode( $raw, true );
		if ( ! is_array( $decoded ) ) {
			return array();
		}
		$clean = array();
		foreach ( $decoded as $row ) {
			$item = self::normalize_contact_row( $row );
			if ( $item ) {
				$clean[] = $item;
			}
		}
		return $clean;
	}

	/**
	 * Persists contact actions, applying type-aware sanitization
	 * before storing.
	 *
	 * @param int   $post_id
	 * @param array $rows
	 */
	public static function save_contact( $post_id, $rows ) {
		if ( ! is_array( $rows ) ) {
			$rows = array();
		}
		$sanitized = array();
		foreach ( $rows as $row ) {
			$item = self::normalize_contact_row( $row, true );
			if ( $item ) {
				unset( $item['href'] );
				$sanitized[] = $item;
			}
		}
		if ( empty( $sanitized ) ) {
			delete_post_meta( $post_id, self::KEY_CONTACT );
		} else {
			update_post_meta( $post_id, self::KEY_CONTACT, wp_json_encode( $sanitized, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES ) );
		}
	}

	/**
	 * Validates and normalizes one contact row. Returns null when the
	 * row is unusable. The $strict flag enforces input-time
	 * sanitization (used on save); when false (read path) we still
	 * sanitize but tolerate slightly looser data.
	 *
	 * @param array $row
	 * @param bool  $strict
	 * @return array|null { type, label, value, href }
	 */
	public static function normalize_contact_row( $row, $strict = false ) {
		if ( ! is_array( $row ) ) {
			return null;
		}
		$type  = isset( $row['type'] ) ? strtolower( trim( (string) $row['type'] ) ) : '';
		$label = isset( $row['label'] ) ? sanitize_text_field( $row['label'] ) : '';
		$value = isset( $row['value'] ) ? trim( (string) $row['value'] ) : '';

		if ( ! in_array( $type, self::ALLOWED_CONTACT_TYPES, true ) ) {
			return null;
		}
		if ( '' === $value ) {
			return null;
		}

		$href = '';

		if ( 'email' === $type ) {
			$email = sanitize_email( $value );
			if ( ! is_email( $email ) ) {
				return null;
			}
			$value = $email;
			$href  = 'mailto:' . rawurlencode( $email );
		} elseif ( 'whatsapp' === $type ) {
			$digits = preg_replace( '/[^0-9]/', '', $value );
			if ( strlen( $digits ) < 6 ) {
				return null;
			}
			$value = $digits;
			$href  = 'https://wa.me/' . $digits;
		} else { // custom
			$url = esc_url_raw( $value, array( 'http', 'https', 'mailto', 'tel' ) );
			if ( ! $url ) {
				return null;
			}
			$lower = strtolower( $url );
			if ( strpos( $lower, 'javascript:' ) === 0 || strpos( $lower, 'data:' ) === 0 ) {
				return null;
			}
			$value = $url;
			$href  = $url;
		}

		if ( '' === $label ) {
			$label = ucfirst( $type );
		}

		return array(
			'type'  => $type,
			'label' => $label,
			'value' => $value,
			'href'  => $href,
		);
	}
}