<?php
/**
 * Device condition (responsive, CSS-based).
 *
 * @package BlockSieve
 */

namespace BlockSieve\Conditions\Definitions;

use BlockSieve\Conditions\AbstractCondition;
use BlockSieve\Conditions\Context\Context;

/**
 * Targets a block to specific device classes using responsive CSS.
 *
 * Unlike the other conditions, device targeting is **not** evaluated with
 * user-agent detection. The value lists the devices on which the block should
 * remain visible; `RenderService` wraps a block carrying this condition with
 * responsive utility classes (`blocksieve-hide-on-*`) that `assets/css/front.css`
 * hides through media queries.
 *
 * `evaluate()` therefore always passes server-side — the actual hiding is done
 * client-side by CSS. This keeps the engine model uniform while honouring the
 * "no user-agent detection, use CSS media queries" requirement.
 */
final class DeviceCondition extends AbstractCondition {

	/**
	 * Devices recognised by the editor.
	 */
	public const DEVICES = array( 'desktop', 'tablet', 'mobile' );

	/**
	 * Gets the unique condition identifier.
	 *
	 * @return string
	 */
	public function id(): string {
		return 'device';
	}

	/**
	 * Gets the translated human label.
	 *
	 * @return string
	 */
	public function label(): string {
		return __( 'Device', 'blocksieve' );
	}

	/**
	 * Gets the translated description shown in the UI.
	 *
	 * @return string
	 */
	public function description(): string {
		return __( 'Show the block only on selected devices (responsive, CSS-based).', 'blocksieve' );
	}

	/**
	 * Gets the category used to group this condition in the UI.
	 *
	 * @return string
	 */
	public function category(): string {
		return 'device';
	}

	/**
	 * Gets the list of supported operator identifiers.
	 *
	 * @return string[]
	 */
	public function operators(): array {
		return array( 'is' );
	}

	/**
	 * Gets the JSON-schema-like description of the value field for the UI.
	 *
	 * @return array
	 */
	public function value_schema(): array {
		return array(
			'type'       => 'object',
			'properties' => array(
				'devices' => array(
					'type'  => 'array',
					'items' => array(
						'type' => 'string',
						'enum' => self::DEVICES,
					),
				),
			),
		);
	}

	/**
	 * Gets the default value for a newly created condition of this type.
	 *
	 * @return mixed
	 */
	public function default_value() {
		return array(
			'devices' => self::DEVICES,
		);
	}

	/**
	 * Validates a value against this condition's schema.
	 *
	 * @param mixed $value Value to validate.
	 * @return bool
	 */
	public function is_valid_value( $value ): bool {
		// Legacy single-device string, still honoured by RenderService.
		if ( is_string( $value ) ) {
			return in_array( $value, self::DEVICES, true );
		}

		if ( ! is_array( $value ) || ! isset( $value['devices'] ) || ! is_array( $value['devices'] ) ) {
			return false;
		}

		foreach ( $value['devices'] as $device ) {
			if ( ! in_array( $device, self::DEVICES, true ) ) {
				return false;
			}
		}

		return true;
	}

	/**
	 * Evaluates the condition against the given context.
	 *
	 * @param Context $context  Request context value object.
	 * @param string  $operator Operator identifier.
	 * @param mixed   $value    Configured value.
	 * @return bool
	 */
	public function evaluate( Context $context, string $operator, $value ): bool {
		// Responsive hiding is performed client-side via CSS (see RenderService
		// + front.css). Server-side evaluation never hides on device, so this
		// condition always passes and only contributes its wrapper classes.
		return true;
	}
}