<?php

namespace JVBase\rest\routes;

use JVBase\importers\JaneAppClientImporter;
use JVBase\importers\JaneAppSalesImporter;
use JVBase\rest\Rest;
use JVBase\rest\Route;
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 ImporterRoutes extends Rest
{
	/**
	 * Register REST routes
	 */
	public function registerRoutes(): void
	{
		// Client import endpoint
		Route::for('jane/import-clients')
			->post([$this, 'importClients'])
			->args([
				'options' => 'string', // JSON string of options
			])
			->auth('admin')
			->rateLimit(3, 300)
			->register(); // 3 imports per 5 minutes

		// Sales import endpoint
		Route::for('jane/import-sales')
			->post([$this, 'importSales'])
			->args([
				'options' => 'string', // JSON string of options
			])
			->auth('admin')
			->rateLimit(3, 300)
			->register(); // 3 imports per 5 minutes

		// Get import status
		Route::for(Route::pattern('jane/import-status/{id}'))
			->get([$this, 'getImportStatus'])
			->arg('id', 'string|required')
			->auth('admin')
			->rateLimit(30)
			->register();
	}

	/**
	 * 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
	 */
	public function importClients(WP_REST_Request $request): WP_REST_Response
	{
		// Get uploaded file
		$files = $request->get_file_params();
		if (empty($files['file'])) {
			return $this->error('No file uploaded', 'no_file', 400);
		}

		$file = $files['file'];

		// Validate file type
		if (!$this->isValidCSV($file)) {
			return $this->error('Invalid file type. Please upload a CSV file.', 'invalid_file', 400);
		}

		// Get and parse options
		$options_param = $request->get_param('options');
		$options = !empty($options_param) ? json_decode($options_param, true) : [];

		$default_options = [
			'update_existing' => true,
			'create_users' => true,
			'send_welcome_email' => false
		];
		$options = wp_parse_args($options, $default_options);

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

		if (is_wp_error($results)) {
			$this->logError('Client import failed', [
				'error' => $results->get_error_message(),
				'file' => $file['name']
			]);

			return $this->error(
				$results->get_error_message(),
				'import_failed',
				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 $this->success([
			'import_id' => $import_id,
			'results' => $results,
			'summary' => $this->generateClientImportSummary($results)
		]);
	}

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

		$file = $files['file'];

		// Validate file type
		if (!$this->isValidCSV($file)) {
			return $this->error('Invalid file type. Please upload a CSV file.', 'invalid_file', 400);
		}

		// Get and parse options
		$options_param = $request->get_param('options');
		$options = !empty($options_param) ? json_decode($options_param, true) : [];

		$default_options = [
			'skip_existing' => true
		];
		$options = wp_parse_args($options, $default_options);

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

		if (is_wp_error($results)) {
			$this->logError('Sales import failed', [
				'error' => $results->get_error_message(),
				'file' => $file['name']
			]);

			return $this->error(
				$results->get_error_message(),
				'import_failed',
				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 $this->success([
			'import_id' => $import_id,
			'results' => $results,
			'summary' => $this->generateSalesImportSummary($results)
		]);
	}

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

		if (!$import_data) {
			return $this->notFound('Import not found or expired');
		}

		return $this->success($import_data);
	}

	/**
	 * 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) . '.';
	}
}