<?php
/**
 * Public Agent Field Sanitizer
 *
 * Cleans one incoming value against the field type declared in a panel schema.
 * Everything the REST endpoint writes to the settings option passes through
 * here, so a panel author never has to write sanitizing code.
 *
 * @package Aisentic\PublicAgent
 */

declare(strict_types=1);

namespace Aisentic\PublicAgent;

defined( 'ABSPATH' ) || exit;

/**
 * Field sanitizer class
 */
class Field_Sanitizer {

	/**
	 * Clean a raw value for its field type.
	 *
	 * @param array $field Normalized field schema.
	 * @param mixed $value Raw value from the request.
	 * @return mixed Cleaned value, or null when the type is unknown.
	 */
	public static function sanitize( array $field, $value ) {
		$type = isset( $field['type'] ) ? (string) $field['type'] : '';

		switch ( $type ) {
			case 'text':
				$text = sanitize_text_field( (string) $value );
				return isset( $field['maxChars'] ) ? mb_substr( $text, 0, (int) $field['maxChars'] ) : $text;

			case 'textarea':
				return sanitize_textarea_field( (string) $value );

			case 'toggle':
				return (bool) $value;

			case 'color':
				$hex = sanitize_hex_color( (string) $value );
				return null === $hex ? '' : $hex;

			case 'image':
				// Only an image from this site's media library; 0 means none.
				$id = absint( $value );
				return $id && wp_attachment_is_image( $id ) ? $id : 0;

			case 'select':
				return self::sanitize_select( $field, $value );

			case 'number':
				return self::sanitize_number( $field, $value );

			case 'prompts':
				return self::sanitize_prompts( $field, $value );
		}

		return null;
	}

	/**
	 * Keep the value only when it is one of the declared options.
	 *
	 * @param array $field Field schema.
	 * @param mixed $value Raw value.
	 * @return string
	 */
	private static function sanitize_select( array $field, $value ): string {
		$options = isset( $field['options'] ) && is_array( $field['options'] )
			? array_map( 'strval', array_keys( $field['options'] ) )
			: [];

		$value = (string) $value;

		if ( in_array( $value, $options, true ) ) {
			return $value;
		}

		return isset( $field['default'] ) ? (string) $field['default'] : '';
	}

	/**
	 * Cast to a whole number and hold it inside the declared range.
	 *
	 * @param array $field Field schema.
	 * @param mixed $value Raw value.
	 * @return int
	 */
	private static function sanitize_number( array $field, $value ): int {
		$number = absint( $value );

		if ( isset( $field['min'] ) && $number < (int) $field['min'] ) {
			$number = (int) $field['min'];
		}

		if ( isset( $field['max'] ) && $number > (int) $field['max'] ) {
			$number = (int) $field['max'];
		}

		return $number;
	}

	/**
	 * Clean a starter prompt list: drop blanks, cut long text, cap the count.
	 *
	 * @param array $field Field schema.
	 * @param mixed $value Raw value.
	 * @return array
	 */
	private static function sanitize_prompts( array $field, $value ): array {
		if ( ! is_array( $value ) ) {
			return [];
		}

		$max_items = isset( $field['max'] ) ? (int) $field['max'] : 8;
		$max_chars = isset( $field['maxChars'] ) ? (int) $field['maxChars'] : 100;
		$list      = [];

		foreach ( $value as $item ) {
			if ( ! is_string( $item ) ) {
				continue;
			}

			$clean = trim( sanitize_text_field( $item ) );

			if ( '' === $clean ) {
				continue;
			}

			if ( mb_strlen( $clean ) > $max_chars ) {
				$clean = mb_substr( $clean, 0, $max_chars );
			}

			$list[] = $clean;

			if ( count( $list ) >= $max_items ) {
				break;
			}
		}

		return $list;
	}
}