// ECOin - Copyright (c) - 2014/2021 - GPLv3 - epsylon@riseup.net (https://03c8.net)
#ifndef ECOIN_KEY_H
#define ECOIN_KEY_H

#include <stdexcept>
#include <vector>

#include "allocators.h"
#include "serialize.h"
#include "uint256.h"
#include "util.h"

#include <openssl/ec.h> // for EC_KEY definition

class key_error : public std::runtime_error
{
public:
    explicit key_error(const std::string& str) : std::runtime_error(str) {}
};

class CKeyID : public uint160
{
public:
    CKeyID() : uint160(0) { }
    CKeyID(const uint160 &in) : uint160(in) { }
};

class CScriptID : public uint160
{
public:
    CScriptID() : uint160(0) { }
    CScriptID(const uint160 &in) : uint160(in) { }
};

class CPubKey {
private:
    std::vector<unsigned char> vchPubKey;
    friend class CKey;

public:
    CPubKey() { }
    CPubKey(const std::vector<unsigned char> &vchPubKeyIn) : vchPubKey(vchPubKeyIn) { }
    friend bool operator==(const CPubKey &a, const CPubKey &b) { return a.vchPubKey == b.vchPubKey; }
    friend bool operator!=(const CPubKey &a, const CPubKey &b) { return a.vchPubKey != b.vchPubKey; }
    friend bool operator<(const CPubKey &a, const CPubKey &b) { return a.vchPubKey < b.vchPubKey; }

    IMPLEMENT_SERIALIZE(
        READWRITE(vchPubKey);
    )

    CKeyID GetID() const {
        return CKeyID(Hash160(vchPubKey));
    }

    uint256 GetHash() const {
        return Hash(vchPubKey.begin(), vchPubKey.end());
    }

    bool IsValid() const {
        return vchPubKey.size() == 33 || vchPubKey.size() == 65;
    }

    bool IsCompressed() const {
        return vchPubKey.size() == 33;
    }

    std::vector<unsigned char> Raw() const {
        return vchPubKey;
    }
};


typedef std::vector<unsigned char, secure_allocator<unsigned char> > CPrivKey;
typedef std::vector<unsigned char, secure_allocator<unsigned char> > CSecret;
class CKey
{
protected:
    EC_KEY* pkey;
    bool fSet;
    bool fCompressedPubKey;

    void SetCompressedPubKey();

public:

    void Reset();

    CKey();
    CKey(const CKey& b);

    CKey& operator=(const CKey& b);

    ~CKey();

    bool IsNull() const;
    bool IsCompressed() const;

    void MakeNewKey(bool fCompressed);
    bool SetPrivKey(const CPrivKey& vchPrivKey);
    bool SetSecret(const CSecret& vchSecret, bool fCompressed = false);
    CSecret GetSecret(bool &fCompressed) const;
    CPrivKey GetPrivKey() const;
    bool SetPubKey(const CPubKey& vchPubKey);
    CPubKey GetPubKey() const;

    bool Sign(uint256 hash, std::vector<unsigned char>& vchSig);

    bool SignCompact(uint256 hash, std::vector<unsigned char>& vchSig);

    bool SetCompactSignature(uint256 hash, const std::vector<unsigned char>& vchSig);

    bool Verify(uint256 hash, const std::vector<unsigned char>& vchSig);

    bool VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig);

    bool IsValid();
};

#endif