ThreadSafeDictionary

class ThreadSafeDictionary<Key: Hashable, Value> {
    private var dictionary: [Key: Value] = [:]
    private let concurrentQueue = DispatchQueue(label: "com.concurrentQueue")
    
    func setValue(_ value: Value, key: Key) {
        concurrentQueue.async(flags: .barrier) {
            self.dictionary[key] = value
        }
    }
    
    func value(forKey key: Key) -> Value? {
        var result: Value?
        concurrentQueue.async(flags: .barrier) {
            result = self.dictionary[key]
        }
        return result
    }
    
    func removeValue(forkey key: Key) {
        concurrentQueue.async(flags: .barrier) {
            self.dictionary.removeValue(forKey: key)
        }
    }
    
    func removeAll() {
        concurrentQueue.async(flags: .barrier) {
            self.dictionary.removeAll()
        }
    }
    
    var allKeys: [Key] {
        var keys = [Key]()
        concurrentQueue.sync {
            keys = Array(self.dictionary.keys)
        }
        return keys
    }
    
    var allValues: [Value] {
        var values = [Value]()
        concurrentQueue.sync {
            values = Array(self.dictionary.values)
        }
        return values
    }
    
    func contains(key: Key) -> Bool {
        var result = false
        concurrentQueue.sync {
            result = self.dictionary.keys.contains(key)
        }
        return result
    }
    
    func print() {
        concurrentQueue.sync {
            Swift.print(dictionary)
        }
    }  
}