
<?php
final class SitiDeliveryTimeNotice {
	private const OPTION_KEY = 'lb_levertijd_settings';
	private const META_SUPPLIER_OVERRIDE = '_lb_levertijd_supplier_override';

	public static function init(): void {
		add_action('init', [__CLASS__, 'load_textdomain']);
		add_action('admin_menu', [__CLASS__, 'register_settings_page']);
		add_action('admin_init', [__CLASS__, 'maybe_save_settings']);
		add_action('wp_enqueue_scripts', [__CLASS__, 'enqueue_assets']);

		add_action('woocommerce_product_options_general_product_data', [__CLASS__, 'render_product_override_field']);
		add_action('woocommerce_process_product_meta', [__CLASS__, 'save_product_override_field']);

		add_filter('woocommerce_get_availability_text', [__CLASS__, 'filter_availability_text'], 10, 2);
		add_action('woocommerce_after_add_to_cart_form', [__CLASS__, 'render_card_below_cart'], 5);
		add_filter('woocommerce_available_variation', [__CLASS__, 'add_variation_levertijd_data'], 10, 3);
	}

	public static function load_textdomain(): void {
		load_plugin_textdomain(SITI_DELIVERY_TIME_NOTICES_SLUG, false, dirname(plugin_basename(__FILE__)) . '/languages');
	}

	public static function enqueue_assets(): void {
		wp_enqueue_script(
			'lb-levertijden',
			plugins_url('assets/js/levertijden.js', __FILE__),
			['jquery'],
			'1.0.2',
			true
		);
	}

	private static function get_settings(): array {
		$defaults = [
			'default_range' => [
				'min' => 1,
				'max' => 2,
			],
			'suppliers' => [],
		];

		$options = get_option(self::OPTION_KEY, []);
		if (!is_array($options)) {
			$options = [];
		}

		$options = wp_parse_args($options, $defaults);
		$options['default_range'] = self::sanitize_range($options['default_range']);

		if (!is_array($options['suppliers'])) {
			$options['suppliers'] = [];
		} else {
			foreach ($options['suppliers'] as $key => $range) {
				$options['suppliers'][$key] = self::sanitize_range($range);
			}
		}

		$options['suppliers'] = self::ensure_known_suppliers($options['suppliers'], $options['default_range']);

		return $options;
	}

	public static function register_settings_page(): void {
		add_submenu_page(
			'woocommerce',
			__('Levertijden', SITI_DELIVERY_TIME_NOTICES_SLUG),
			__('Levertijden', SITI_DELIVERY_TIME_NOTICES_SLUG),
			'manage_woocommerce',
			'lb-levertijden',
			[__CLASS__, 'render_settings_page']
		);
	}

	public static function maybe_save_settings(): void {
		if (!isset($_POST['lb_levertijden_nonce']) || !wp_verify_nonce(sanitize_text_field(wp_unslash($_POST['lb_levertijden_nonce'])), 'lb_save_levertijden')) {
			return;
		}

		if (!current_user_can('manage_woocommerce')) {
			return;
		}

		$default_min = isset($_POST['lb_default_min']) ? absint($_POST['lb_default_min']) : 1;
		$default_max = isset($_POST['lb_default_max']) ? absint($_POST['lb_default_max']) : $default_min;

		$default_range = self::sanitize_range([
			'min' => $default_min,
			'max' => $default_max,
		]);

		$suppliers = [];
		if (!empty($_POST['lb_suppliers']) && is_array($_POST['lb_suppliers'])) {
			$data = wp_unslash($_POST['lb_suppliers']);
			$keys = $data['key'] ?? [];
			$labels = $data['label'] ?? [];
			$mins = $data['min'] ?? [];
			$maxes = $data['max'] ?? [];
			$count = max(count($keys), count($labels), count($mins), count($maxes));

			for ($i = 0; $i < $count; $i++) {
				$key = sanitize_key($keys[$i] ?? '');
				$label = sanitize_text_field($labels[$i] ?? '');
				$min = absint($mins[$i] ?? 0);
				$max = absint($maxes[$i] ?? 0);

				if ($key === '' || $label === '') {
					continue;
				}

				$range = self::sanitize_range([
					'min' => $min,
					'max' => $max,
					'label' => $label,
				]);

				$range['label'] = $label;
				$suppliers[$key] = $range;
			}
		}

		update_option(
			self::OPTION_KEY,
			[
				'default_range' => $default_range,
				'suppliers'     => $suppliers,
			]
		);

		add_settings_error('lb_levertijden', 'lb_levertijden_saved', __('Levertijden opgeslagen.', SITI_DELIVERY_TIME_NOTICES_SLUG), 'updated');
	}

	public static function render_settings_page(): void {
		$settings = self::get_settings();
		$suppliers = $settings['suppliers'];
		$select_options = self::get_supplier_dropdown_options(array_keys($suppliers));
		settings_errors('lb_levertijden');
		?>
		<div class="wrap">
			<h1><?php esc_html_e('Levertijden configuratie', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></h1>
			<form method="post">
				<?php wp_nonce_field('lb_save_levertijden', 'lb_levertijden_nonce'); ?>

				<h2><?php esc_html_e('Standaard levertijd (voorraad aanwezig)', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></h2>
				<table class="form-table">
					<tr>
						<th scope="row"><?php esc_html_e('Minimale werkdagen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
						<td><input type="number" min="1" name="lb_default_min" value="<?php echo esc_attr($settings['default_range']['min']); ?>" /></td>
					</tr>
					<tr>
						<th scope="row"><?php esc_html_e('Maximale werkdagen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
						<td><input type="number" min="1" name="lb_default_max" value="<?php echo esc_attr($settings['default_range']['max']); ?>" /></td>
					</tr>
				</table>

				<h2><?php esc_html_e('Levertijd per leverancier', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></h2>
				<p><?php esc_html_e('Voeg elke leverancier toe zoals de waarde in het veld _wpci_supplier wordt opgeslagen.', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></p>
				<table class="widefat fixed striped">
					<thead>
						<tr>
							<th><?php esc_html_e('Leverancier sleutel', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
							<th><?php esc_html_e('Label', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
							<th><?php esc_html_e('Min. werkdagen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
							<th><?php esc_html_e('Max. werkdagen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
							<th><?php esc_html_e('Acties', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></th>
						</tr>
					</thead>
					<tbody id="lb-supplier-rows">
						<?php if (!empty($suppliers)) : ?>
							<?php foreach ($suppliers as $key => $range) : ?>
								<?php self::render_supplier_row($key, $range, $select_options); ?>
							<?php endforeach; ?>
						<?php endif; ?>
					</tbody>
				</table>
				<p>
					<button type="button" class="button" id="lb-add-supplier"><?php esc_html_e('Leverancier toevoegen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></button>
				</p>

				<p class="submit">
					<button type="submit" class="button button-primary"><?php esc_html_e('Opslaan', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></button>
				</p>
			</form>
		</div>
		<script>
		(function(){
			const container = document.getElementById('lb-supplier-rows');
			const addButton = document.getElementById('lb-add-supplier');
			if(!container || !addButton){ return; }

			const template = <?php echo wp_json_encode(self::get_supplier_row_template($select_options, $settings['default_range'])); ?>;

			addButton.addEventListener('click', function(){
				const row = document.createElement('tr');
				row.innerHTML = template;
				container.appendChild(row);
			});

			container.addEventListener('click', function(event){
				if(event.target.classList.contains('lb-remove-supplier')){
					event.preventDefault();
					const row = event.target.closest('tr');
					if(row){
						row.remove();
					}
				}
			});
		}());
		</script>
		<?php
	}

	private static function render_supplier_row(string $key, array $range, array $select_options): void {
		$label = $range['label'] ?? $key;
		?>
		<tr>
			<?php echo self::get_supplier_row_inner_html($key, ['label' => $label, 'min' => $range['min'], 'max' => $range['max']], $select_options); ?>
		</tr>
		<?php
	}

	private static function get_supplier_row_inner_html(string $key, array $range, array $select_options): string {
		$label = $range['label'] ?? '';
		ob_start();
		?>
			<td><?php echo self::render_supplier_select($key, $select_options); ?></td>
			<td><input type="text" name="lb_suppliers[label][]" value="<?php echo esc_attr($label); ?>" /></td>
			<td><input type="number" min="1" name="lb_suppliers[min][]" value="<?php echo esc_attr($range['min']); ?>" /></td>
			<td><input type="number" min="1" name="lb_suppliers[max][]" value="<?php echo esc_attr($range['max']); ?>" /></td>
			<td><button type="button" class="button lb-remove-supplier"><?php esc_html_e('Verwijderen', SITI_DELIVERY_TIME_NOTICES_SLUG); ?></button></td>
		<?php
		return ob_get_clean();
	}

	private static function get_supplier_row_template(array $select_options, array $default_range): string {
		$content = self::get_supplier_row_inner_html('', [
			'label' => '',
			'min'   => $default_range['min'] ?? 1,
			'max'   => $default_range['max'] ?? 1,
		], $select_options);

		return $content;
	}

	private static function sanitize_range(array $range): array {
		$min = isset($range['min']) ? absint($range['min']) : 0;
		$max = isset($range['max']) ? absint($range['max']) : 0;

		if ($min === 0 && $max === 0) {
			$min = 1;
			$max = 1;
		}

		if ($max === 0) {
			$max = $min;
		}

		if ($min === 0) {
			$min = $max;
		}

		if ($max < $min) {
			$temp = $min;
			$min = $max;
			$max = $temp;
		}

		return [
			'min' => max(1, $min),
			'max' => max(1, $max),
			'label' => $range['label'] ?? '',
		];
	}

	private static function ensure_known_suppliers(array $current, array $default_range): array {
		$known = self::get_distinct_supplier_sources();
		foreach ($known as $key => $label) {
			if (!isset($current[$key])) {
				$current[$key] = [
					'min'   => $default_range['min'],
					'max'   => $default_range['max'],
					'label' => $label ?: $key,
				];
				continue;
			}

			if (empty($current[$key]['label']) && $label) {
				$current[$key]['label'] = $label;
			}
		}

		ksort($current);

		return $current;
	}

	private static function get_supplier_dropdown_options(array $current_keys = []): array {
		$options = [
			'' => __('Selecteer leverancier', SITI_DELIVERY_TIME_NOTICES_SLUG),
		];

		foreach (self::get_distinct_supplier_sources() as $key => $label) {
			$options[$key] = $label ?: $key;
		}

		foreach ($current_keys as $key) {
			if ($key !== '' && !isset($options[$key])) {
				$options[$key] = $key;
			}
		}

		return $options;
	}

	private static function render_supplier_select(string $selected, array $options): string {
		if ($selected !== '' && !array_key_exists($selected, $options)) {
			$options[$selected] = $selected;
		}

		$html = '<select name="lb_suppliers[key][]">';
		foreach ($options as $value => $label) {
			$html .= sprintf(
				'<option value="%s"%s>%s</option>',
				esc_attr($value),
				selected($selected, (string) $value, false),
				esc_html($label)
			);
		}
		$html .= '</select>';

		return $html;
	}

	private static function get_distinct_supplier_sources(): array {
		static $cache = null;
		if ($cache !== null) {
			return $cache;
		}

		global $wpdb;
		$table = $wpdb->postmeta;
		$rows = $wpdb->get_col(
			$wpdb->prepare(
				"SELECT DISTINCT meta_value FROM {$table} WHERE meta_key = %s AND meta_value <> ''",
				'_wpci_supplier'
			)
		);

		$cache = [];
		if ($rows) {
			foreach ($rows as $raw) {
				foreach (self::normalize_supplier_values($raw) as $value) {
					$key = sanitize_key($value);
					if ($key === '' || isset($cache[$key])) {
						continue;
					}
					$cache[$key] = $value;
				}
			}
		}

		return $cache;
	}

	private static function normalize_supplier_values($raw): array {
		$result = [];
		$value = maybe_unserialize($raw);

		if (is_array($value)) {
			array_walk_recursive($value, function ($item) use (&$result) {
				if (is_scalar($item)) {
					$item = trim((string) $item);
					if ($item !== '') {
						$result[] = $item;
					}
				}
			});
		} elseif (is_scalar($value)) {
			$value = trim((string) $value);
			if ($value !== '') {
				$result[] = $value;
			}
		}

		return $result;
	}

	public static function render_product_override_field(): void {
		$settings = self::get_settings();
		$choices = [
			''          => __('Automatisch (voorraad / leverancier)', SITI_DELIVERY_TIME_NOTICES_SLUG),
			'default'   => __('Altijd standaard levertijd', SITI_DELIVERY_TIME_NOTICES_SLUG),
		];

		foreach ($settings['suppliers'] as $key => $range) {
			$choices[$key] = sprintf(
				'%s (%s)',
				$range['label'] ?: $key,
				self::format_range_text($range)
			);
		}

		global $post;
		$value = get_post_meta($post->ID, self::META_SUPPLIER_OVERRIDE, true);

		echo '<div class="options_group">';
		woocommerce_wp_select([
			'id'          => self::META_SUPPLIER_OVERRIDE,
			'label'       => __('Levertijd leverancier', SITI_DELIVERY_TIME_NOTICES_SLUG),
			'options'     => $choices,
			'value'       => $value,
			'desc_tip'    => false,
			'description' => __('Kies een leverancier om de levertijd van dit product te forceren.', SITI_DELIVERY_TIME_NOTICES_SLUG),
		]);
		echo '</div>';
	}

	public static function save_product_override_field(int $post_id): void {
		if (!isset($_POST[self::META_SUPPLIER_OVERRIDE])) {
			return;
		}

		$value = sanitize_text_field(wp_unslash($_POST[self::META_SUPPLIER_OVERRIDE]));
		update_post_meta($post_id, self::META_SUPPLIER_OVERRIDE, $value);
	}

	public static function filter_availability_text(string $availability, WC_Product $product): string {
		$text = self::get_levertijd_text($product, false);
		if ($text) {
			return sprintf(__('Verwachte levertijd: %s', SITI_DELIVERY_TIME_NOTICES_SLUG), $text);
		}

		return $availability;
	}

	public static function render_card_below_cart(): void {
		if (!is_product()) {
			return;
		}

		global $product;
		if (!$product instanceof WC_Product) {
			return;
		}

		if ($product->is_type('variable')) {
			$text = '';
		} else {
			$text = self::get_levertijd_text($product);
			if (!$text) {
				return;
			}
		}

		echo '<div class="lb-levertijd-card list-group list-group-flush mb-4" data-default-text="' . esc_attr($text) . '" style="' . ($text === '' ? 'display:none;' : '') . '">';
		echo '<div class="list-group-item"><i class="fa fa-truck" aria-hidden="true"></i> <span class="lb-levertijd-text">' . esc_html($text) . '</span></div>';
		echo '</div>';
	}

	public static function add_variation_levertijd_data($variation_data, $product = null, $variation = null) {
		if ($variation instanceof WC_Product_Variation) {
			$text = self::get_levertijd_text($variation);
			$variation_data['lb_levertijd'] = $text;
		}

		return $variation_data;
	}

	private static function get_product_meta_with_parent(WC_Product $product, string $key, bool $allow_array = false) {
		$value = get_post_meta($product->get_id(), $key, true);
		if (($value === '' || ($allow_array && empty($value))) && $product->get_parent_id()) {
			$value = get_post_meta($product->get_parent_id(), $key, true);
		}

		if (!$allow_array && is_array($value)) {
			return '';
		}

		return $value;
	}

	private static function get_levertijd_text(WC_Product $product, bool $with_label = true): string {
		$range = self::resolve_range_for_product($product);
		if (!$range) {
			return '';
		}

		$text = self::format_range_text($range);
		if ($text === '') {
			return '';
		}

		return $with_label ? sprintf(__('Verwachte levertijd: %s', SITI_DELIVERY_TIME_NOTICES_SLUG), $text) : $text;
	}

	private static function resolve_range_for_product(WC_Product $product): ?array {
		$settings = self::get_settings();

		$override = self::get_product_meta_with_parent($product, self::META_SUPPLIER_OVERRIDE);
		if ($override && $override !== 'auto') {
			if ($override === 'default') {
				return $settings['default_range'];
			}

			if (isset($settings['suppliers'][$override])) {
				return $settings['suppliers'][$override];
			}
		}

		if (self::has_local_stock($product)) {
			return $settings['default_range'];
		}

		$supplier = self::get_supplier_key($product);
		if ($supplier && isset($settings['suppliers'][$supplier])) {
			return $settings['suppliers'][$supplier];
		}

		return $settings['default_range'];
	}

	private static function has_local_stock(WC_Product $product): bool {
		$explicit_stock = self::get_product_meta_with_parent($product, '_stock');
		if ($explicit_stock !== '') {
			$qty = function_exists('wc_stock_amount') ? wc_stock_amount($explicit_stock) : (int) $explicit_stock;
			return $qty > 0;
		}

		if ($product->managing_stock()) {
			$qty = $product->get_stock_quantity();
			if ($qty !== null) {
				return $qty > 0;
			}
		}

		return $product->is_in_stock();
	}

	private static function get_supplier_key(WC_Product $product): string {
		$supplier_meta = self::get_product_meta_with_parent($product, '_wpci_supplier', true);
		if ($supplier_meta === '' || $supplier_meta === null) {
			return '';
		}

		$supplier = $supplier_meta;
		if (is_string($supplier) && is_serialized($supplier)) {
			$maybe = maybe_unserialize($supplier);
			if (is_array($maybe)) {
				$supplier = $maybe;
			}
		}

		if (is_array($supplier)) {
			$supplier = reset($supplier);
		}

		return sanitize_key((string) $supplier);
	}

	private static function format_range_text(array $range): string {
		$min = absint($range['min'] ?? 0);
		$max = absint($range['max'] ?? 0);

		if ($min === 0 && $max === 0) {
			return '';
		}

		if ($max === 0) {
			$max = $min;
		}

		if ($min === $max) {
			$text = sprintf(_n('%d werkdag', '%d werkdagen', $min, SITI_DELIVERY_TIME_NOTICES_SLUG), $min);
		} else {
			$text = sprintf(__('van %d tot %d werkdagen', SITI_DELIVERY_TIME_NOTICES_SLUG), $min, $max);
		}

		return $text;
	}
}