<?php

namespace JVBase\routes;

use JVBase\managers\JaneClientImporter;
use JVBase\managers\JaneSalesImporter;
use WP_REST_Request;
use WP_REST_Response;
use WP_Error;

if (!defined('ABSPATH')) {
	exit;
}

/**
 * JaneApp Import Routes
 *
 * REST API endpoints for importing JaneApp data
 */
class JaneImportRoutes
{
	protected string $namespace;

	public function __construct()
	{
		$this->namespace = BASE . 'v1';
	}

	/**
	 * Register REST routes
	 */
	public function registerRoutes(): void
	{
		// Client import endpoint
		register_rest_route($this->namespace, '/jane/import-clients', [
			'methods' => 'POST',
			'callback' => [$this, 'importClients'],
			'permission_callback' => [$this, 'checkAdminPermission'],
			'args' => [
				'file' => [
					'required' => true,
					'description' => 'CSV file containing client data'
				],
				'options' => [
					'required' => false,
					'default' => [],
					'description' => 'Import options'
				]
			]
		]);

		// Sales import endpoint
		register_rest_route($this->namespace, '/jane/import-sales', [
			'methods' => 'POST',
			'callback' => [$this, 'importSales'],
			'permission_callback' => [$this, 'checkAdminPermission'],
			'args' => [
				'file' => [
					'required' => true,
					'description' => 'CSV file containing sales data'
				],
				'options' => [
					'required' => false,
					'default' => [],
					'description' => 'Import options'
				]
			]
		]);

		// Get import status
		register_rest_route($this->namespace, '/jane/import-status/(?P<id>[\w-]+)', [
			'methods' => 'GET',
			'callback' => [$this, 'getImportStatus'],
			'permission_callback' => [$this, 'checkAdminPermission']
		]);
	}

	/**
	 * Check if user has admin permissions
	 */
	public function checkAdminPermission(): bool
	{
		return current_user_can('manage_options');
	}

	/**
	 * Import clients from CSV
	 *
	 * @param WP_REST_Request $request
	 * @return WP_REST_Response|WP_Error
	 */
	public function importClients(WP_REST_Request $request)
	{
		// Get uploaded file
		$files = $request->get_file_params();
		if (empty($files['file'])) {
			return new WP_Error('no_file', 'No file uploaded', ['status' => 400]);
		}

		$file = $files['file'];

		// Validate file type
		if (!$this->isValidCSV($file)) {
			return new WP_Error('invalid_file', 'Invalid file type. Please upload a CSV file.', ['status' => 400]);
		}

		// Get options
		$options = $request->get_param('options') ?: [];
		$default_options = [
			'update_existing' => true,
			'create_users' => true,
			'send_welcome_email' => false
		];
		$options = wp_parse_args($options, $default_options);

		// Process import
		$importer = new JaneClientImporter();
		$results = $importer->importFromCSV($file['tmp_name'], $options);

		if (is_wp_error($results)) {
			return new WP_Error(
				'import_failed',
				$results->get_error_message(),
				['status' => 500]
			);
		}

		// Store results in transient for status checking
		$import_id = wp_generate_password(12, false);
		set_transient('jane_import_' . $import_id, [
			'type' => 'clients',
			'results' => $results,
			'completed_at' => current_time('mysql')
		], HOUR_IN_SECONDS);

		return new WP_REST_Response([
			'success' => true,
			'import_id' => $import_id,
			'results' => $results,
			'summary' => $this->generateClientImportSummary($results)
		], 200);
	}

	/**
	 * Import sales from CSV
	 *
	 * @param WP_REST_Request $request
	 * @return WP_REST_Response|WP_Error
	 */
	public function importSales(WP_REST_Request $request)
	{
		// Get uploaded file
		$files = $request->get_file_params();
		if (empty($files['file'])) {
			return new WP_Error('no_file', 'No file uploaded', ['status' => 400]);
		}

		$file = $files['file'];

		// Validate file type
		if (!$this->isValidCSV($file)) {
			return new WP_Error('invalid_file', 'Invalid file type. Please upload a CSV file.', ['status' => 400]);
		}

		// Get options
		$options = $request->get_param('options') ?: [];
		$default_options = [
			'skip_existing' => true
		];
		$options = wp_parse_args($options, $default_options);

		// Process import
		$importer = new JaneSalesImporter();
		$results = $importer->importFromCSV($file['tmp_name'], $options);

		if (is_wp_error($results)) {
			return new WP_Error(
				'import_failed',
				$results->get_error_message(),
				['status' => 500]
			);
		}

		// Store results in transient for status checking
		$import_id = wp_generate_password(12, false);
		set_transient('jane_import_' . $import_id, [
			'type' => 'sales',
			'results' => $results,
			'completed_at' => current_time('mysql')
		], HOUR_IN_SECONDS);

		return new WP_REST_Response([
			'success' => true,
			'import_id' => $import_id,
			'results' => $results,
			'summary' => $this->generateSalesImportSummary($results)
		], 200);
	}

	/**
	 * Get import status by ID
	 *
	 * @param WP_REST_Request $request
	 * @return WP_REST_Response|WP_Error
	 */
	public function getImportStatus(WP_REST_Request $request)
	{
		$import_id = $request->get_param('id');
		$import_data = get_transient('jane_import_' . $import_id);

		if (!$import_data) {
			return new WP_Error(
				'import_not_found',
				'Import not found or expired',
				['status' => 404]
			);
		}

		return new WP_REST_Response([
			'success' => true,
			'data' => $import_data
		], 200);
	}

	/**
	 * Validate CSV file
	 *
	 * @param array $file Uploaded file data
	 * @return bool
	 */
	protected function isValidCSV(array $file): bool
	{
		// Check file extension
		$ext = strtolower(pathinfo($file['name'], PATHINFO_EXTENSION));
		if ($ext !== 'csv') {
			return false;
		}

		// Check MIME type
		$allowed_types = ['text/csv', 'text/plain', 'application/csv', 'application/vnd.ms-excel'];
		if (!in_array($file['type'], $allowed_types)) {
			return false;
		}

		// Check if file is actually readable as CSV
		$handle = fopen($file['tmp_name'], 'r');
		if (!$handle) {
			return false;
		}

		$header = fgetcsv($handle);
		fclose($handle);

		return !empty($header);
	}

	/**
	 * Generate human-readable summary of client import
	 *
	 * @param array $results Import results
	 * @return string
	 */
	protected function generateClientImportSummary(array $results): string
	{
		$summary = [];

		if ($results['created'] > 0) {
			$summary[] = "{$results['created']} new users created";
		}

		if ($results['updated'] > 0) {
			$summary[] = "{$results['updated']} existing users updated";
		}

		if ($results['skipped'] > 0) {
			$summary[] = "{$results['skipped']} rows skipped";
		}

		if (count($results['errors']) > 0) {
			$summary[] = count($results['errors']) . " errors encountered";
		}

		if (count($results['unmatched_emails']) > 0) {
			$summary[] = count($results['unmatched_emails']) . " unmatched emails";
		}

		return implode('. ', $summary) . '.';
	}

	/**
	 * Generate human-readable summary of sales import
	 *
	 * @param array $results Import results
	 * @return string
	 */
	protected function generateSalesImportSummary(array $results): string
	{
		$summary = [];

		if ($results['consultations'] > 0) {
			$summary[] = "{$results['consultations']} consultations processed";
		}

		if ($results['treatments'] > 0) {
			$summary[] = "{$results['treatments']} treatments recorded";
		}

		if ($results['skipped'] > 0) {
			$summary[] = "{$results['skipped']} rows skipped";
		}

		if (count($results['errors']) > 0) {
			$summary[] = count($results['errors']) . " errors encountered";
		}

		if (count($results['unmatched_guids']) > 0) {
			$summary[] = count($results['unmatched_guids']) . " unmatched patient GUIDs";
		}

		if (count($results['no_referral']) > 0) {
			$summary[] = count($results['no_referral']) . " users without referral records";
		}

		return implode('. ', $summary) . '.';
	}
}