<?php
/**
 * Email Renderer
 * 
 * Renders email templates with content
 * 
 * @package WooNooW\Core\Notifications
 */

namespace WooNooW\Core\Notifications;

class EmailRenderer {
	
	/**
	 * Instance
	 */
	private static $instance = null;
	
	/**
	 * Get instance
	 */
	public static function instance() {
		if (null === self::$instance) {
			self::$instance = new self();
		}
		return self::$instance;
	}
	
	/**
	 * Render email
	 * 
	 * @param string $event_id Event ID (order_placed, order_processing, etc.)
	 * @param string $recipient_type Recipient type (staff, customer)
	 * @param mixed $data Order, Product, or Customer object
	 * @param array $extra_data Additional data
	 * @return array|null ['to', 'subject', 'body']
	 */
	public function render($event_id, $recipient_type, $data, $extra_data = []) {
		// Get template settings
		$template_settings = $this->get_template_settings($event_id, $recipient_type);
		
		if (!$template_settings) {
			return null;
		}
		
		// Get recipient email
		$to = $this->get_recipient_email($recipient_type, $data);
		
		if (!$to) {
			return null;
		}
		
		// Get variables
		$variables = $this->get_variables($event_id, $data, $extra_data);
		
		// Replace variables in subject and content
		$subject = $this->replace_variables($template_settings['subject'], $variables);
		$content = $this->replace_variables($template_settings['body'], $variables);
		
		// Get HTML template design
		$design_template = $this->get_design_template($template_settings['design'] ?? 'modern');
		
		// Render final HTML
		$html = $this->render_html($design_template, $content, $subject, $variables);
		
		return [
			'to' => $to,
			'subject' => $subject,
			'body' => $html,
		];
	}
	
	/**
	 * Get template settings
	 * 
	 * @param string $event_id
	 * @param string $recipient_type
	 * @return array|null
	 */
	private function get_template_settings($event_id, $recipient_type) {
		// Get saved template
		$template = TemplateProvider::get_template($event_id, 'email');
		
		if (!$template) {
			return null;
		}
		
		// Get design template preference
		$settings = get_option('woonoow_notification_settings', []);
		$design = $settings['email_design_template'] ?? 'modern';
		
		return [
			'subject' => $template['subject'] ?? '',
			'body' => $template['body'] ?? '',
			'design' => $design,
		];
	}
	
	/**
	 * Get recipient email
	 * 
	 * @param string $recipient_type
	 * @param mixed $data
	 * @return string|null
	 */
	private function get_recipient_email($recipient_type, $data) {
		if ($recipient_type === 'staff') {
			return get_option('admin_email');
		}
		
		// Customer
		if ($data instanceof \WC_Order) {
			return $data->get_billing_email();
		}
		
		if ($data instanceof \WC_Customer) {
			return $data->get_email();
		}
		
		return null;
	}
	
	/**
	 * Get variables for template
	 * 
	 * @param string $event_id
	 * @param mixed $data
	 * @param array $extra_data
	 * @return array
	 */
	private function get_variables($event_id, $data, $extra_data = []) {
		$variables = [
			'store_name' => get_bloginfo('name'),
			'store_url' => home_url(),
			'site_title' => get_bloginfo('name'),
		];
		
		// Order variables
		if ($data instanceof \WC_Order) {
			$variables = array_merge($variables, [
				'order_number' => $data->get_order_number(),
				'order_id' => $data->get_id(),
				'order_date' => $data->get_date_created()->date('F j, Y'),
				'order_total' => $data->get_formatted_order_total(),
				'order_subtotal' => wc_price($data->get_subtotal()),
				'order_tax' => wc_price($data->get_total_tax()),
				'order_shipping' => wc_price($data->get_shipping_total()),
				'order_discount' => wc_price($data->get_discount_total()),
				'order_status' => wc_get_order_status_name($data->get_status()),
				'order_url' => $data->get_view_order_url(),
				'payment_method' => $data->get_payment_method_title(),
				'shipping_method' => $data->get_shipping_method(),
				'customer_name' => $data->get_formatted_billing_full_name(),
				'customer_first_name' => $data->get_billing_first_name(),
				'customer_last_name' => $data->get_billing_last_name(),
				'customer_email' => $data->get_billing_email(),
				'customer_phone' => $data->get_billing_phone(),
				'billing_address' => $data->get_formatted_billing_address(),
				'shipping_address' => $data->get_formatted_shipping_address(),
			]);
			
			// Order items
			$items_html = '';
			foreach ($data->get_items() as $item) {
				$product = $item->get_product();
				$items_html .= sprintf(
					'<tr><td>%s × %d</td><td>%s</td></tr>',
					$item->get_name(),
					$item->get_quantity(),
					wc_price($item->get_total())
				);
			}
			$variables['order_items'] = $items_html;
		}
		
		// Product variables
		if ($data instanceof \WC_Product) {
			$variables = array_merge($variables, [
				'product_id' => $data->get_id(),
				'product_name' => $data->get_name(),
				'product_sku' => $data->get_sku(),
				'product_price' => wc_price($data->get_price()),
				'product_url' => get_permalink($data->get_id()),
				'stock_quantity' => $data->get_stock_quantity(),
				'stock_status' => $data->get_stock_status(),
			]);
		}
		
		// Customer variables
		if ($data instanceof \WC_Customer) {
			$variables = array_merge($variables, [
				'customer_id' => $data->get_id(),
				'customer_name' => $data->get_display_name(),
				'customer_first_name' => $data->get_first_name(),
				'customer_last_name' => $data->get_last_name(),
				'customer_email' => $data->get_email(),
				'customer_username' => $data->get_username(),
			]);
		}
		
		// Merge extra data
		$variables = array_merge($variables, $extra_data);
		
		return apply_filters('woonoow_email_variables', $variables, $event_id, $data);
	}
	
	/**
	 * Replace variables in text
	 * 
	 * @param string $text
	 * @param array $variables
	 * @return string
	 */
	private function replace_variables($text, $variables) {
		foreach ($variables as $key => $value) {
			$text = str_replace('{' . $key . '}', $value, $text);
		}
		
		return $text;
	}
	
	/**
	 * Get design template path
	 * 
	 * @param string $design Template name (modern, classic, minimal)
	 * @return string
	 */
	private function get_design_template($design) {
		$template_path = WOONOOW_PATH . 'templates/emails/' . $design . '.html';
		
		// Allow filtering template path
		$template_path = apply_filters('woonoow_email_template', $template_path, $design);
		
		// Fallback to modern if template doesn't exist
		if (!file_exists($template_path)) {
			$template_path = WOONOOW_PATH . 'templates/emails/modern.html';
		}
		
		return $template_path;
	}
	
	/**
	 * Render HTML email
	 * 
	 * @param string $template_path Path to HTML template
	 * @param string $content Email content (HTML)
	 * @param string $subject Email subject
	 * @param array $variables All variables
	 * @return string
	 */
	private function render_html($template_path, $content, $subject, $variables) {
		if (!file_exists($template_path)) {
			// Fallback to plain HTML
			return $content;
		}
		
		// Load template
		$html = file_get_contents($template_path);
		
		// Replace placeholders
		$html = str_replace('{{email_heading}}', $subject, $html);
		$html = str_replace('{{email_content}}', $content, $html);
		$html = str_replace('{{store_name}}', $variables['store_name'], $html);
		$html = str_replace('{{store_url}}', $variables['store_url'], $html);
		$html = str_replace('{{current_year}}', date('Y'), $html);
		
		// Replace all other variables
		foreach ($variables as $key => $value) {
			$html = str_replace('{{' . $key . '}}', $value, $html);
		}
		
		return $html;
	}
}