<?php
/**
 * Central settings model, defaults, migration and sanitization.
 *
 * @package AkavaBackToTop
 */

namespace Akava\BackToTop;

use Akava\BackToTop\Support\Sanitizer;

defined( 'ABSPATH' ) || exit;

final class Config {

	const OPTION         = 'akava_btt_options';
	const SETTINGS_GROUP = 'akava_btt_options_group';
	const VERSION_OPTION = 'akava_btt_version';
	const REVIEW_PROMPT_OPTION = 'akava_btt_review_prompt';
	const PRODUCT_URL       = 'https://akava.site/back-to-top';
	const DOCUMENTATION_URL = 'https://akava.site/back-to-top/#documentation';
	const DEVELOPER_URL      = 'https://akava.site/';
	const REVIEW_URL         = 'https://wordpress.org/plugins/akava-back-to-top/#reviews';

	/** @var array|null */
	private static $cache = null;

	/** @var array|null */
	private static $runtime_cache = null;

	/**
	 * Return the complete settings array.
	 *
	 * @return array
	 */
	public static function all() {
		if ( null === self::$cache ) {
			$stored = get_option( self::OPTION, array() );
			$stored = is_array( $stored ) ? self::migrate_legacy( $stored ) : array();
			self::$cache = self::normalize( array_merge( self::defaults(), $stored ), false );
		}

		if ( null === self::$runtime_cache ) {
			/**
			 * Filter runtime settings without changing the stored option.
			 *
			 * Returned values are normalized again so a typo in custom code cannot
			 * create invalid CSS, unsafe output, or an unusable touch target.
			 *
			 * @param array $settings Sanitized plugin settings.
			 */
			$filtered = apply_filters( 'akava_btt_options', self::$cache );
			if ( is_array( $filtered ) ) {
				$filtered = self::apply_runtime_legacy_aliases( $filtered );
				$filtered = array_merge( self::$cache, $filtered );
			} else {
				$filtered = self::$cache;
			}
			self::$runtime_cache = self::normalize( $filtered, false );
		}

		return self::$runtime_cache;
	}

	/**
	 * Read one setting.
	 *
	 * @param string $key Setting key.
	 * @param mixed  $fallback Fallback value.
	 * @return mixed
	 */
	public static function get( $key, $fallback = null ) {
		$settings = self::all();
		return array_key_exists( $key, $settings ) ? $settings[ $key ] : $fallback;
	}

	/**
	 * Clear request-local caches.
	 *
	 * @return void
	 */
	public static function flush_cache() {
		self::$cache         = null;
		self::$runtime_cache = null;
	}

	/**
	 * Product defaults.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			'enabled'                 => true,
			'show_desktop'            => true,
			'show_tablet'             => true,
			'show_mobile'             => true,
			'show_threshold'          => 320,
			'visibility_mode'         => 'threshold',
			'scroll_duration'         => 460,
			'hide_on_short_pages'     => true,
			'show_progress'           => true,
			'progress_scope'          => 'auto',
			'progress_selector'       => '',
			'return_point_enabled'     => false,
			'return_label'             => '',
			'smart_dock_enabled'       => true,
			'smart_dock_gap'           => 12,
			'smart_dock_opposite_side' => true,
			'smart_dock_selectors'     => '',
			'desktop_position'        => 'bottom-end',
			'tablet_position'         => 'bottom-end',
			'mobile_position'         => 'bottom-end',
			'desktop_offset_inline'   => 24,
			'tablet_offset_inline'    => 20,
			'mobile_offset_inline'    => 16,
			'desktop_offset_block'    => 24,
			'tablet_offset_block'     => 20,
			'mobile_offset_block'     => 16,
			'desktop_button_size'     => 54,
			'tablet_button_size'      => 52,
			'mobile_button_size'      => 48,
			'desktop_icon_size'       => 24,
			'tablet_icon_size'        => 23,
			'mobile_icon_size'        => 22,
			'z_index'                 => 9990,
			'button_style'            => 'gradient',
			'button_shape'            => 'circle',
			'color_source'            => 'custom',
			'bg_color_start'          => '#2563eb',
			'bg_color_end'            => '#1d4ed8',
			'icon_color'              => '#ffffff',
			'progress_color'          => '#93c5fd',
			'border_color'            => '#ffffff',
			'border_width'            => 0,
			'shadow_enabled'          => true,
			'hover_animation'         => true,
			'icon_type'               => 'chevron',
			'custom_icon_id'          => 0,
			'show_tooltip'            => true,
			'button_label'            => '',
			'mobile_breakpoint'       => 782,
			'tablet_breakpoint'       => 1024,
			'delete_on_uninstall'     => false,
		);
	}

	/**
	 * Sanitize settings before storage.
	 *
	 * @param mixed $input Raw settings.
	 * @return array
	 */
	public static function sanitize( $input ) {
		$input = is_array( $input ) ? self::migrate_legacy( $input ) : array();
		$clean = self::normalize( $input, true );
		self::flush_cache();
		return $clean;
	}

	/**
	 * Normalize settings at both write and read boundaries.
	 *
	 * @param mixed $input Raw settings.
	 * @param bool  $report_errors Whether to register admin settings notices.
	 * @return array
	 */
	private static function normalize( $input, $report_errors ) {
		$input     = is_array( $input ) ? $input : array();
		$defaults  = self::defaults();
		$clean     = array();
		$positions = array( 'top-start', 'top-end', 'bottom-start', 'bottom-end' );
		$devices   = array( 'desktop', 'tablet', 'mobile' );

		$clean['enabled']             = Sanitizer::boolean( $input['enabled'] ?? false );
		$clean['show_desktop']        = Sanitizer::boolean( $input['show_desktop'] ?? false );
		$clean['show_tablet']         = Sanitizer::boolean( $input['show_tablet'] ?? false );
		$clean['show_mobile']         = Sanitizer::boolean( $input['show_mobile'] ?? false );
		$clean['show_threshold']      = Sanitizer::integer( $input['show_threshold'] ?? null, 0, 5000, $defaults['show_threshold'] );
		$clean['visibility_mode']     = Sanitizer::choice( $input['visibility_mode'] ?? '', array( 'threshold', 'scroll-up' ), $defaults['visibility_mode'] );
		$clean['scroll_duration']     = Sanitizer::integer( $input['scroll_duration'] ?? null, 0, 1500, $defaults['scroll_duration'] );
		$clean['hide_on_short_pages']      = Sanitizer::boolean( $input['hide_on_short_pages'] ?? false );
		$clean['show_progress']            = Sanitizer::boolean( $input['show_progress'] ?? false );
		$clean['progress_scope']           = Sanitizer::choice( $input['progress_scope'] ?? '', array( 'auto', 'page', 'custom' ), $defaults['progress_scope'] );
		$clean['progress_selector']        = Sanitizer::selector( $input['progress_selector'] ?? '' );
		$clean['return_point_enabled']     = Sanitizer::boolean( $input['return_point_enabled'] ?? false );
		$clean['return_label']             = Sanitizer::label( $input['return_label'] ?? '', '', 64 );
		$clean['smart_dock_enabled']       = Sanitizer::boolean( $input['smart_dock_enabled'] ?? false );
		$clean['smart_dock_gap']           = Sanitizer::integer( $input['smart_dock_gap'] ?? null, 4, 48, $defaults['smart_dock_gap'] );
		$clean['smart_dock_opposite_side'] = Sanitizer::boolean( $input['smart_dock_opposite_side'] ?? false );
		$clean['smart_dock_selectors']     = Sanitizer::selector_lines( $input['smart_dock_selectors'] ?? '' );

		foreach ( $devices as $device ) {
			$clean[ $device . '_position' ]      = Sanitizer::choice( $input[ $device . '_position' ] ?? '', $positions, $defaults[ $device . '_position' ] );
			$clean[ $device . '_offset_inline' ] = Sanitizer::integer( $input[ $device . '_offset_inline' ] ?? null, 0, 240, $defaults[ $device . '_offset_inline' ] );
			$clean[ $device . '_offset_block' ]  = Sanitizer::integer( $input[ $device . '_offset_block' ] ?? null, 0, 240, $defaults[ $device . '_offset_block' ] );
			$clean[ $device . '_button_size' ]   = Sanitizer::integer( $input[ $device . '_button_size' ] ?? null, 44, 96, $defaults[ $device . '_button_size' ] );
			$clean[ $device . '_icon_size' ]     = Sanitizer::integer( $input[ $device . '_icon_size' ] ?? null, 14, 44, $defaults[ $device . '_icon_size' ] );
			$clean[ $device . '_icon_size' ]     = min( $clean[ $device . '_icon_size' ], max( 14, $clean[ $device . '_button_size' ] - 12 ) );
		}

		$clean['z_index']             = Sanitizer::integer( $input['z_index'] ?? null, 1, 2147483000, $defaults['z_index'] );
		$clean['button_style']        = Sanitizer::choice( $input['button_style'] ?? '', array( 'gradient', 'solid', 'glass', 'outline' ), $defaults['button_style'] );
		$clean['button_shape']        = Sanitizer::choice( $input['button_shape'] ?? '', array( 'circle', 'square', 'rounded' ), $defaults['button_shape'] );
		$clean['color_source']        = Sanitizer::choice( $input['color_source'] ?? '', array( 'custom', 'theme' ), $defaults['color_source'] );
		$clean['bg_color_start']      = Sanitizer::color( $input['bg_color_start'] ?? '', $defaults['bg_color_start'] );
		$clean['bg_color_end']        = Sanitizer::color( $input['bg_color_end'] ?? '', $defaults['bg_color_end'] );
		$clean['icon_color']          = Sanitizer::color( $input['icon_color'] ?? '', $defaults['icon_color'] );
		$clean['progress_color']      = Sanitizer::color( $input['progress_color'] ?? '', $defaults['progress_color'] );
		$clean['border_color']        = Sanitizer::color( $input['border_color'] ?? '', $defaults['border_color'] );
		$clean['border_width']        = Sanitizer::integer( $input['border_width'] ?? null, 0, 8, $defaults['border_width'] );
		$clean['shadow_enabled']      = Sanitizer::boolean( $input['shadow_enabled'] ?? false );
		$clean['hover_animation']     = Sanitizer::boolean( $input['hover_animation'] ?? false );
		$clean['icon_type']           = Sanitizer::choice( $input['icon_type'] ?? '', array( 'chevron', 'arrow', 'double', 'minimal', 'bar-arrow', 'caret', 'triangle', 'north', 'rocket', 'page-top', 'custom' ), $defaults['icon_type'] );
		$clean['custom_icon_id']      = Sanitizer::image_attachment_id( $input['custom_icon_id'] ?? 0 );
		$clean['show_tooltip']        = Sanitizer::boolean( $input['show_tooltip'] ?? false );
		$clean['button_label']        = Sanitizer::label( $input['button_label'] ?? '', '', 80 );
		$clean['mobile_breakpoint']   = Sanitizer::integer( $input['mobile_breakpoint'] ?? null, 320, 1024, $defaults['mobile_breakpoint'] );
		$clean['tablet_breakpoint']   = Sanitizer::integer( $input['tablet_breakpoint'] ?? null, 600, 1600, $defaults['tablet_breakpoint'] );
		$clean['delete_on_uninstall'] = Sanitizer::boolean( $input['delete_on_uninstall'] ?? false );

		if ( $clean['tablet_breakpoint'] <= $clean['mobile_breakpoint'] ) {
			$clean['tablet_breakpoint'] = min( 1600, max( $defaults['tablet_breakpoint'], $clean['mobile_breakpoint'] + 1 ) );
			if ( $report_errors && function_exists( 'add_settings_error' ) ) {
				add_settings_error(
					self::OPTION,
					'akava_btt_invalid_breakpoints',
					__( 'The tablet breakpoint must be larger than the mobile breakpoint, so it was adjusted automatically.', 'akava-back-to-top' ),
					'warning'
				);
			}
		}

		if ( 'custom' === $clean['progress_scope'] && '' === $clean['progress_selector'] ) {
			$clean['progress_scope'] = 'auto';
			if ( $report_errors && function_exists( 'add_settings_error' ) ) {
				add_settings_error(
					self::OPTION,
					'akava_btt_missing_progress_selector',
					__( 'ContentProgress was switched to automatic detection because the custom content selector is empty.', 'akava-back-to-top' ),
					'warning'
				);
			}
		}

		if ( $clean['return_point_enabled'] && '' === $clean['return_label'] ) {
			$clean['return_point_enabled'] = false;
			if ( $report_errors && function_exists( 'add_settings_error' ) ) {
				add_settings_error(
					self::OPTION,
					'akava_btt_missing_return_label',
					__( 'ReturnPoint was disabled because its accessible return label is empty. Add the label in the language of your site, then enable the feature again.', 'akava-back-to-top' ),
					'warning'
				);
			}
		}

		if ( 'custom' === $clean['icon_type'] && ! $clean['custom_icon_id'] ) {
			$clean['icon_type'] = $defaults['icon_type'];
			if ( $report_errors && function_exists( 'add_settings_error' ) ) {
				add_settings_error(
					self::OPTION,
					'akava_btt_invalid_custom_icon',
					__( 'The custom icon was not a valid WordPress image attachment, so the default icon was restored.', 'akava-back-to-top' ),
					'warning'
				);
			}
		}

		return $clean;
	}

	/**
	 * Honor 2.0 filter keys when custom code still supplies the old schema.
	 *
	 * Stored options no longer contain these keys after normalization, so their
	 * presence here indicates an intentional runtime override.
	 *
	 * @param array $settings Filtered settings.
	 * @return array
	 */
	private static function apply_runtime_legacy_aliases( array $settings ) {
		if ( array_key_exists( 'position', $settings ) ) {
			foreach ( array( 'desktop', 'tablet', 'mobile' ) as $device ) {
				$settings[ $device . '_position' ] = $settings['position'];
			}
		}
		if ( array_key_exists( 'offset_inline', $settings ) ) {
			foreach ( array( 'desktop', 'tablet', 'mobile' ) as $device ) {
				$settings[ $device . '_offset_inline' ] = $settings['offset_inline'];
			}
		}
		if ( array_key_exists( 'offset_block', $settings ) ) {
			foreach ( array( 'desktop', 'tablet', 'mobile' ) as $device ) {
				$settings[ $device . '_offset_block' ] = $settings['offset_block'];
			}
		}
		if ( array_key_exists( 'button_size', $settings ) ) {
			$settings['desktop_button_size'] = $settings['button_size'];
			$settings['tablet_button_size']  = $settings['button_size'];
		}
		if ( array_key_exists( 'button_size_mobile', $settings ) ) {
			$settings['mobile_button_size'] = $settings['button_size_mobile'];
		}
		if ( array_key_exists( 'icon_size', $settings ) ) {
			foreach ( array( 'desktop', 'tablet', 'mobile' ) as $device ) {
				$settings[ $device . '_icon_size' ] = $settings['icon_size'];
			}
		}
		if ( array_key_exists( 'display_mode', $settings ) ) {
			$mode = Sanitizer::choice( $settings['display_mode'], array( 'all', 'desktop', 'mobile' ), 'all' );
			$settings['show_desktop'] = in_array( $mode, array( 'all', 'desktop' ), true );
			$settings['show_tablet']  = 'all' === $mode;
			$settings['show_mobile']  = in_array( $mode, array( 'all', 'mobile' ), true );
		}

		return $settings;
	}

	/**
	 * Convert 1.x and 2.0 settings without moving existing buttons unexpectedly.
	 *
	 * @param array $stored Stored settings.
	 * @return array
	 */
	public static function migrate_legacy( array $stored ) {
		// Existing installations keep whole-page progress until the owner opts in.
		$installed_version = (string) get_option( self::VERSION_OPTION, '' );
		if ( ! array_key_exists( 'progress_scope', $stored ) && '' !== $installed_version && version_compare( $installed_version, '2.3.0', '<' ) ) {
			$stored['progress_scope'] = 'page';
		}
		if ( isset( $stored['offset_x'] ) && ! isset( $stored['offset_inline'] ) ) {
			$stored['offset_inline'] = $stored['offset_x'];
		}
		if ( isset( $stored['offset_y'] ) && ! isset( $stored['offset_block'] ) ) {
			$stored['offset_block'] = $stored['offset_y'];
		}

		$is_rtl       = self::site_uses_rtl();
		$position_map = $is_rtl
			? array(
				'top-left'     => 'top-end',
				'top-right'    => 'top-start',
				'bottom-left'  => 'bottom-end',
				'bottom-right' => 'bottom-start',
			)
			: array(
				'top-left'     => 'top-start',
				'top-right'    => 'top-end',
				'bottom-left'  => 'bottom-start',
				'bottom-right' => 'bottom-end',
			);

		if ( isset( $stored['position'], $position_map[ $stored['position'] ] ) ) {
			$stored['position'] = $position_map[ $stored['position'] ];
		}

		if ( isset( $stored['display_mode'] ) && ! isset( $stored['show_desktop'], $stored['show_tablet'], $stored['show_mobile'] ) ) {
			$stored['show_desktop'] = in_array( $stored['display_mode'], array( 'all', 'desktop' ), true );
			$stored['show_tablet']  = 'all' === $stored['display_mode'];
			$stored['show_mobile']  = in_array( $stored['display_mode'], array( 'all', 'mobile' ), true );
		}

		$legacy_position = isset( $stored['position'] ) ? $stored['position'] : null;
		$legacy_inline   = isset( $stored['offset_inline'] ) ? $stored['offset_inline'] : null;
		$legacy_block    = isset( $stored['offset_block'] ) ? $stored['offset_block'] : null;
		$legacy_size     = isset( $stored['button_size'] ) ? $stored['button_size'] : null;
		$legacy_mobile   = isset( $stored['button_size_mobile'] ) ? $stored['button_size_mobile'] : $legacy_size;
		$legacy_icon     = isset( $stored['icon_size'] ) ? $stored['icon_size'] : null;

		foreach ( array( 'desktop', 'tablet', 'mobile' ) as $device ) {
			if ( null !== $legacy_position && ! isset( $stored[ $device . '_position' ] ) ) {
				$stored[ $device . '_position' ] = $legacy_position;
			}
			if ( null !== $legacy_inline && ! isset( $stored[ $device . '_offset_inline' ] ) ) {
				$stored[ $device . '_offset_inline' ] = $legacy_inline;
			}
			if ( null !== $legacy_block && ! isset( $stored[ $device . '_offset_block' ] ) ) {
				$stored[ $device . '_offset_block' ] = $legacy_block;
			}
			if ( null !== $legacy_icon && ! isset( $stored[ $device . '_icon_size' ] ) ) {
				$stored[ $device . '_icon_size' ] = $legacy_icon;
			}
		}

		if ( null !== $legacy_size ) {
			$stored['desktop_button_size'] = $stored['desktop_button_size'] ?? $legacy_size;
			$stored['tablet_button_size']  = $stored['tablet_button_size'] ?? $legacy_size;
		}
		if ( null !== $legacy_mobile ) {
			$stored['mobile_button_size'] = $stored['mobile_button_size'] ?? $legacy_mobile;
		}

		if ( isset( $stored['custom_icon_url'] ) && ! isset( $stored['custom_icon_id'] ) ) {
			$stored['custom_icon_id'] = attachment_url_to_postid( esc_url_raw( $stored['custom_icon_url'] ) );
		}

		return $stored;
	}

	/**
	 * Determine the public site's direction, not the current admin locale.
	 *
	 * @return bool
	 */
	private static function site_uses_rtl() {
		if ( ! function_exists( 'is_rtl' ) ) {
			return false;
		}

		$site_locale = (string) get_option( 'WPLANG', '' );
		$site_locale = '' !== $site_locale ? $site_locale : 'en_US';

		if ( function_exists( 'switch_to_locale' ) && function_exists( 'restore_previous_locale' ) ) {
			$switched = switch_to_locale( $site_locale );
			$is_rtl   = is_rtl();
			if ( $switched ) {
				restore_previous_locale();
			}
			return $is_rtl;
		}

		return is_rtl();
	}
}