<?php

declare(strict_types=1);

namespace App\Services;

use Exception;

class ConsentService
{
	private FileStorage $storage;
	private const CONSENT_VERSION = 'webwizard-mvp-2026-06-12';

	public function __construct()
	{
		$this->storage = new FileStorage();
	}

	/**
	 * Saves user consent for a specific project.
	 */
	public function saveConsent(string $projectId, string $userId, string $consentText): bool
	{
		// Verify project exists and belongs to user
		$projectData = $this->storage->get("projects/{$projectId}.json");
		if (!$projectData) {
			throw new Exception("Project not found.", 404);
		}
		if ($projectData['user_id'] !== $userId) {
			throw new Exception("Unauthorized access to project.", 403);
		}

		$consentData = [
			'project_id' => $projectId,
			'user_id' => $userId,
			'consent_text_version' => self::CONSENT_VERSION,
			'consent_text' => $consentText,
			'accepted' => true,
			'accepted_at' => gmdate('Y-m-d\TH:i:s\Z')
		];

		return $this->storage->put("consent/{$projectId}.json", $consentData);
	}

	/**
	 * Checks if a project has a valid consent record.
	 */
	public function hasConsent(string $projectId): bool
	{
		return $this->storage->exists("consent/{$projectId}.json");
	}

	/**
	 * Returns the current consent version.
	 */
	public function getVersion(): string
	{
		return self::CONSENT_VERSION;
	}
}