QuickDrop/NearbyShare/Data+Extensions.swift

//
//  Data+Extensions.swift
//  QuickDrop
//
//  Created by Grishka on 08.04.2023.
//

import CoreFoundation
import Foundation

extension Data {
    func urlSafeBase64EncodedString() -> String {
        return String(base64EncodedString().replacingOccurrences(of: "=", with: "").map {
            if $0 == "/" {
                return "_"
            } else if $0 == "+" {
                return "-"
            } else {
                return $0
            }
        })
    }

    static func randomData(length: Int) -> Data {
        var data = Data(count: length)
        data.withUnsafeMutableBytes {
            guard SecRandomCopyBytes(kSecRandomDefault, length, $0.baseAddress!) == 0 else { fatalError() }
        }
        return data
    }

    static func dataFromUrlSafeBase64(_ str: String) -> Data? {
        var regularB64 = String(str.map {
            if $0 == "_" {
                return "/"
            } else if $0 == "-" {
                return "+"
            } else {
                return $0
            }
        })
        while (regularB64.count % 4) != 0 {
            regularB64 = regularB64 + "="
        }
        return Data(base64Encoded: regularB64, options: .ignoreUnknownCharacters)
    }
}