/*
 * Copyright (c)2019 ZeroTier, Inc.
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file in the project's root directory.
 *
 * Change Date: 2026-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2.0 of the Apache License.
 */
/****/

#ifndef ZT_SELFAWARENESS_HPP
#define ZT_SELFAWARENESS_HPP

#include "Address.hpp"
#include "Constants.hpp"
#include "Hashtable.hpp"
#include "InetAddress.hpp"
#include "Mutex.hpp"

namespace ZeroTier {

class RuntimeEnvironment;

/**
 * Tracks changes to this peer's real world addresses
 */
class SelfAwareness {
  public:
    SelfAwareness(const RuntimeEnvironment* renv);

    /**
     * Called when a trusted remote peer informs us of our external network address
     *
     * @param reporter ZeroTier address of reporting peer
     * @param receivedOnLocalAddress Local address on which report was received
     * @param reporterPhysicalAddress Physical address that reporting peer seems to have
     * @param myPhysicalAddress Physical address that peer says we have
     * @param trusted True if this peer is trusted as an authority to inform us of external address changes
     * @param now Current time
     */
    void iam(void* tPtr, const Address& reporter, const int64_t receivedOnLocalSocket, const InetAddress& reporterPhysicalAddress, const InetAddress& myPhysicalAddress, bool trusted, int64_t now);

    /**
     * Return all known external surface addresses reported by peers
     *
     * @return A vector of InetAddress(es)
     */
    std::vector<InetAddress> whoami();

    /**
     * Clean up database periodically
     *
     * @param now Current time
     */
    void clean(int64_t now);

  private:
    struct PhySurfaceKey {
        Address reporter;
        int64_t receivedOnLocalSocket;
        InetAddress reporterPhysicalAddress;
        InetAddress::IpScope scope;

        PhySurfaceKey() : reporter(), scope(InetAddress::IP_SCOPE_NONE)
        {
        }
        PhySurfaceKey(const Address& r, const int64_t rol, const InetAddress& ra, InetAddress::IpScope s) : reporter(r), receivedOnLocalSocket(rol), reporterPhysicalAddress(ra), scope(s)
        {
        }

        inline unsigned long hashCode() const
        {
            return ((unsigned long)reporter.toInt() + (unsigned long)scope);
        }
        inline bool operator==(const PhySurfaceKey& k) const
        {
            return ((reporter == k.reporter) && (receivedOnLocalSocket == k.receivedOnLocalSocket) && (reporterPhysicalAddress == k.reporterPhysicalAddress) && (scope == k.scope));
        }
    };
    struct PhySurfaceEntry {
        InetAddress mySurface;
        uint64_t ts;
        bool trusted;

        PhySurfaceEntry() : mySurface(), ts(0), trusted(false)
        {
        }
        PhySurfaceEntry(const InetAddress& a, const uint64_t t) : mySurface(a), ts(t), trusted(false)
        {
        }
    };

    const RuntimeEnvironment* RR;

    Hashtable<PhySurfaceKey, PhySurfaceEntry> _phy;
    Mutex _phy_m;
};

}   // namespace ZeroTier

#endif