<?php
declare(strict_types=1);

namespace Unsupervised\Schedular\Payment;

use Unsupervised\Schedular\Auth\RoleManager;

class PaymentReportController {

	public const EXPORT_ACTION = 'usc_export_payments';

	public function __construct( private PaymentRepository $payments ) {}

	/**
	 * Render the monthly payments report with HST aggregation. Studio admins see
	 * all instructors; instructors are scoped to their own payments.
	 */
	public function renderPage(): void {
		if ( ! current_user_can( RoleManager::CAP_VIEW_ALL_PAYMENTS ) && ! current_user_can( RoleManager::CAP_VIEW_OWN_PAYMENTS ) ) {
			wp_die( esc_html__( 'You do not have permission to view payment reports.', 'unsupervised-schedular' ) );
		}

		// phpcs:disable WordPress.Security.NonceVerification.Recommended -- read-only report filters, no state change.
		$month        = $this->sanitizeMonth( isset( $_GET['month'] ) ? sanitize_text_field( wp_unslash( $_GET['month'] ) ) : '' );
		$instructorId = isset( $_GET['instructor_id'] ) ? absint( $_GET['instructor_id'] ) : 0;
		// phpcs:enable WordPress.Security.NonceVerification.Recommended

		$instructorId = $this->scopeInstructor( $instructorId );

		$report    = $this->buildReport( $month, $instructorId );
		$canExport = current_user_can( RoleManager::CAP_EXPORT_PAYMENTS );
		$canFilter = current_user_can( RoleManager::CAP_VIEW_ALL_PAYMENTS );
		$exportUrl = wp_nonce_url(
			admin_url( 'admin-post.php?action=' . self::EXPORT_ACTION . '&month=' . rawurlencode( $month ) . '&instructor_id=' . $instructorId ),
			self::EXPORT_ACTION
		);

		$instructors = $canFilter
			? get_users(
				[
					'role'   => RoleManager::INSTRUCTOR,
					'fields' => [ 'ID', 'display_name' ],
				]
			)
			: [];

		include USC_PLUGIN_DIR . 'templates/admin/payment-report.php';
	}

	/**
	 * Stream the report as a CSV download (admin_post handler).
	 */
	public function export(): void {
		if ( ! current_user_can( RoleManager::CAP_EXPORT_PAYMENTS ) ) {
			wp_die( esc_html__( 'You do not have permission to export payments.', 'unsupervised-schedular' ) );
		}

		check_admin_referer( self::EXPORT_ACTION );

		// phpcs:disable WordPress.Security.NonceVerification.Recommended -- nonce checked above.
		$month        = $this->sanitizeMonth( isset( $_GET['month'] ) ? sanitize_text_field( wp_unslash( $_GET['month'] ) ) : '' );
		$instructorId = isset( $_GET['instructor_id'] ) ? absint( $_GET['instructor_id'] ) : 0;
		// phpcs:enable WordPress.Security.NonceVerification.Recommended

		$instructorId = $this->scopeInstructor( $instructorId );
		$report       = $this->buildReport( $month, $instructorId );

		$filename = 'payments-' . $month . '.csv';
		header( 'Content-Type: text/csv; charset=utf-8' );
		header( 'Content-Disposition: attachment; filename="' . $filename . '"' );

		echo $report->toCsv(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- CSV body, not HTML.

		exit;
	}

	/**
	 * Restrict the requested instructor to the current user when they may only
	 * see their own payments.
	 */
	private function scopeInstructor( int $instructorId ): int {
		if ( ! current_user_can( RoleManager::CAP_VIEW_ALL_PAYMENTS ) ) {
			return get_current_user_id();
		}

		return $instructorId;
	}

	/**
	 * Build a report of paid payments for the given `Y-m` month, optionally for
	 * one instructor.
	 */
	private function buildReport( string $month, int $instructorId ): PaymentReport {
		$start = $month . '-01 00:00:00';
		$end   = gmdate( 'Y-m-d H:i:s', strtotime( $month . '-01 00:00:00 +1 month' ) );

		$rows = array_map(
			static function ( Payment $payment ): array {
				$student    = get_userdata( $payment->studentId );
				$instructor = get_userdata( $payment->instructorId );

				return [
					'date'       => substr( (string) $payment->paidAt, 0, 10 ),
					'student'    => $student ? $student->display_name : (string) $payment->studentId,
					'instructor' => $instructor ? $instructor->display_name : (string) $payment->instructorId,
					'method'     => $payment->method,
					'status'     => $payment->status,
					'amount'     => (float) $payment->amount,
					'tax_rate'   => (float) $payment->taxRate,
					'tax_amount' => (float) $payment->taxAmount,
					'total'      => $payment->total(),
				];
			},
			$this->payments->findPaidBetween( $start, $end, $instructorId )
		);

		return new PaymentReport( $rows );
	}

	/**
	 * Validate a `Y-m` month string, defaulting to the current month.
	 */
	private function sanitizeMonth( string $month ): string {
		if ( 1 === preg_match( '/^\d{4}-\d{2}$/', $month ) ) {
			return $month;
		}

		return gmdate( 'Y-m' );
	}
}