#include <net/nc.hpp>

#include <net/ipv4.hpp>
#include <net/dhcp.hpp>
#include <net/eth.hpp>
#include <net/arp.hpp>
#include <net/ntp.hpp>
#include <net/dns.hpp>
#include <net/udp.hpp>
#include <debug.h>

#include "../kernel.h"
#include "../DAPI.hpp"
#include "../Fex.hpp"

/* FIXME: The functions MUST have little endian parameters and return values. */

namespace NetworkInterfaceManager
{
    Vector<Events *> RegisteredEvents;

    NetworkInterface::NetworkInterface()
    {
        mem = new Memory::MemMgr(nullptr, TaskManager->GetCurrentProcess()->memDirectory);
        if (DriverManager->GetDrivers().size() > 0)
        {
            foreach (auto Driver in DriverManager->GetDrivers())
                if (((FexExtended *)((uintptr_t)Driver->Address + EXTENDED_SECTION_ADDRESS))->Driver.Type == FexDriverType::FexDriverType_Network)
                    this->FetchNetworkCards(Driver->DriverUID);
        }
        else
            KPrint("\eE85230No network drivers found! Cannot fetch network cards!");

        DbgNetwork();
    }

    NetworkInterface::~NetworkInterface()
    {
        debug("Destructor called");

        // Stop the network stack
        this->StopNetworkStack();

        // Unregister all events
        for (size_t i = 0; i < RegisteredEvents.size(); i++)
            RegisteredEvents.remove(i);

        // Delete all interfaces and their callbacks and free the memory
        delete mem, mem = nullptr;
    }

    void NetworkInterface::FetchNetworkCards(unsigned long DriverUID)
    {
        KernelCallback *cb = (KernelCallback *)mem->RequestPages(TO_PAGES(sizeof(KernelCallback)));
        memset(cb, 0, sizeof(KernelCallback));
        cb->Reason = FetchReason;
        DriverManager->IOCB(DriverUID, (void *)cb);

        DeviceInterface *Iface = (DeviceInterface *)mem->RequestPages(TO_PAGES(sizeof(DeviceInterface)));
        strcpy(Iface->Name, cb->NetworkCallback.Fetch.Name);
        Iface->ID = this->CardIDs++;
        Iface->MAC.FromHex(cb->NetworkCallback.Fetch.MAC);
        Iface->DriverCallBackAddress = cb;
        Iface->DriverID = DriverUID;
        Interfaces.push_back(Iface);

        foreach (auto var in RegisteredEvents)
            var->OnInterfaceAdded(Iface);

        debug("Network Card: %s; MAC: %#lx", Iface->Name, Iface->MAC.ToHex());
    }

#ifdef DEBUG_NETWORK
#define DbgWriteScreen(x, ...) KPrint(x, ##__VA_ARGS__)
#else
#define DbgWriteScreen(x, ...) debug(x, ##__VA_ARGS__)
#endif

    void NetworkInterface::StartNetworkStack()
    {
        TaskManager->GetCurrentThread()->SetPriority(Tasking::TaskPriority::Critical);
        DeviceInterface *DefaultDevice = nullptr;
        foreach (auto inf in Interfaces)
            if (inf && inf->DriverCallBackAddress)
            {
                DefaultDevice = inf;
                break;
            }

        if (!DefaultDevice)
            error("No network device found!");
        else
        {
            DbgWriteScreen("Using %s (%s) as the default network device", DefaultDevice->Name, DefaultDevice->MAC.ToString());
            NetworkEthernet::Ethernet *eth = new NetworkEthernet::Ethernet(DefaultDevice); // Use the first device found as the ethernet device
            NetworkARP::ARP *arp = new NetworkARP::ARP(eth);
            NetworkIPv4::IPv4 *ipv4 = new NetworkIPv4::IPv4(arp, eth);
            NetworkUDP::UDP *udp = new NetworkUDP::UDP(ipv4, DefaultDevice);
            NetworkUDP::Socket *DHCP_Socket = udp->Connect(InternetProtocol() /* Default value is 255.255.255.255 */, 67);
            NetworkDHCP::DHCP *dhcp = new NetworkDHCP::DHCP(DHCP_Socket, DefaultDevice);
            debug("eth: %p; arp: %p; ipv4: %p; udp: %p; dhcp: %p", eth, arp, ipv4, udp, dhcp);
            udp->Bind(DHCP_Socket, dhcp);
            dhcp->Request();

            DefaultDevice->IP.v4.FromHex(dhcp->IP.v4.ToHex());
            ipv4->SubNetworkMaskIP = dhcp->SubNetworkMask;
            ipv4->GatewayIP = dhcp->Gateway;
            arp->Broadcast(dhcp->Gateway);
            TaskManager->Sleep(200);
            DbgWriteScreen("IP: %s", dhcp->IP.v4.ToStringLittleEndian());
            DbgWriteScreen("SubNetwork Mask: %s", dhcp->SubNetworkMask.v4.ToStringLittleEndian());
            DbgWriteScreen("Gateway: %s", dhcp->Gateway.v4.ToStringLittleEndian());
            DbgWriteScreen("DNS: %s", dhcp->DomainNameSystem.v4.ToStringLittleEndian());
            TaskManager->Sleep(200);

            /* TODO: This is a quick workaround we need DNS resolver asap.

            https://tf.nist.gov/tf-cgi/servers.cgi
            https://www.ntppool.org

            - 0.ro.pool.ntp.org ( {86, 127, 71, 168} )
            - time-a-g.nist.gov ( {129, 6, 15, 28} )
            */
            InternetProtocol ip = {.v4 = {.Address = {129, 6, 15, 28}},
                                   .v6 = {.Address = {}}};
            NetworkUDP::Socket *NTP_Socket = udp->Connect(ip, 123);
            NetworkNTP::NTP *ntp = new NetworkNTP::NTP(NTP_Socket);
            udp->Bind(NTP_Socket, ntp);
            int UnixTimestamp = ntp->ReadTime();
            Time::Clock time = Time::ConvertFromUnix(UnixTimestamp);
            DbgWriteScreen("NTP: %d - %d.%d.%d %d:%d:%d", time.Counter,
                           time.Day, time.Month, time.Year,
                           time.Hour, time.Minute, time.Second);
            TaskManager->Sleep(200);

            /* TODO: Store everything in an vector and initialize all network cards */
        }

        TaskManager->GetCurrentThread()->SetPriority(Tasking::TaskPriority::Idle);
        CPU::Halt(true);
    }

    void NetworkInterface::StopNetworkStack()
    {
        fixme("Stop network stack");
    }

    ReadFSFunction(NetRead)
    {
        fixme("Not implemented.");
        return Size;
    }

    WriteFSFunction(NetWrite)
    {
        fixme("Not implemented.");
        return Size;
    }

    void CallStartNetworkStackWrapper() { NIManager->StartNetworkStack(); }

    void NetworkInterface::StartService()
    {
        this->NetSvcThread = TaskManager->CreateThread(TaskManager->GetCurrentProcess(), (Tasking::IP)CallStartNetworkStackWrapper);
        this->NetSvcThread->Rename("Network Service");
    }

    void NetworkInterface::DrvSend(unsigned int DriverID, unsigned char *Data, unsigned short Size)
    {
        foreach (auto inf in this->Interfaces)
            if (inf->DriverID == DriverID)
                NIManager->Send(inf, Data, Size);
    }

    void NetworkInterface::DrvReceive(unsigned int DriverID, unsigned char *Data, unsigned short Size)
    {
        foreach (auto inf in this->Interfaces)
            if (inf->DriverID == DriverID)
                NIManager->Receive(inf, Data, Size);
    }

    void NetworkInterface::Send(DeviceInterface *Interface, uint8_t *Data, uint64_t Length)
    {
        void *DataToBeSent = mem->RequestPages(TO_PAGES(Length));
        memcpy(DataToBeSent, Data, Length);

        KernelCallback *cb = (KernelCallback *)Interface->DriverCallBackAddress;

        memset(cb, 0, sizeof(KernelCallback));
        cb->Reason = SendReason;
        cb->NetworkCallback.Send.Data = (uint8_t *)DataToBeSent;
        cb->NetworkCallback.Send.Length = Length;
        DriverManager->IOCB(Interface->DriverID, (void *)cb);

        mem->FreePages(DataToBeSent, TO_PAGES(Length));
        foreach (auto var in RegisteredEvents)
            var->OnInterfaceSent(Interface, Data, Length);
    }

    void NetworkInterface::Receive(DeviceInterface *Interface, uint8_t *Data, uint64_t Length)
    {
        foreach (auto re in RegisteredEvents)
            re->OnInterfaceReceived(Interface, Data, Length);
    }

    Events::Events(DeviceInterface *Interface) { RegisteredEvents.push_back(this); }

    Events::~Events()
    {
        for (size_t i = 0; i < RegisteredEvents.size(); i++)
            if (RegisteredEvents[i] == this)
            {
                RegisteredEvents.remove(i);
                return;
            }
    }
}