#pragma once

#include <SDL.h>
#include <cmath>
#include <iostream>

struct Telegram {
    // messages can be dispatched immediately or delayed for a specified amount
    // of time. If a delay is necessary this field is stamped with the time
    // the message should be dispatched.
    Uint32 DispatchTime;

    // the entity that sent this telegram
    int Sender;

    // the entity that is to receive this telegram
    int Receiver;

    // the message itself. These are all enumerated in the file
    //"MessageTypes.h"
    int Msg;

    // any additional information that may accompany the message
    void* ExtraInfo;

    Telegram()
        : DispatchTime(0),
          Sender(-1),
          Receiver(-1),
          Msg(-1),
          ExtraInfo(nullptr) {}

    Telegram(Uint32 time,
             int sender,
             int receiver,
             int msg,
             void* info = nullptr)
        : DispatchTime(time),
          Sender(sender),
          Receiver(receiver),
          Msg(msg),
          ExtraInfo(info) {}
};

// these telegrams will be stored in a priority queue. Therefore the >
// operator needs to be overloaded so that the PQ can sort the telegrams
// by time priority. Note how the times must be smaller than
// SmallestDelay apart before two Telegrams are considered unique.
// const double SmallestDelay = 0.25;
const Uint32 SmallestDelay = 250;

inline bool operator==(const Telegram& t1, const Telegram& t2) {
    return (fabs(t1.DispatchTime - t2.DispatchTime) < SmallestDelay)
           && (t1.Sender == t2.Sender) && (t1.Receiver == t2.Receiver)
           && (t1.Msg == t2.Msg);
}

inline bool operator<(const Telegram& t1, const Telegram& t2) {
    if (t1 == t2) {
        return false;
    }

    else {
        return (t1.DispatchTime < t2.DispatchTime);
    }
}

inline std::ostream& operator<<(std::ostream& os, const Telegram& t) {
    os << "time: " << t.DispatchTime << "  Sender: " << t.Sender
       << "   Receiver: " << t.Receiver << "   Msg: " << t.Msg;

    return os;
}

// handy helper function for dereferencing the ExtraInfo field of the Telegram
// to the required type.
template <class T>
inline T DereferenceToType(void* p) {
    return *(T*)(p);
}