// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2011 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file license.txt or http://www.opensource.org/licenses/mit-license.php.
#ifndef H_BITCOIN_SCRIPT
#define H_BITCOIN_SCRIPT

#include "base58.h"
#include "keystore.h"

#include <string>
#include <vector>

#include <boost/foreach.hpp>

class CTransaction;







inline std::string ValueString(const std::vector<unsigned char>& vch)
{
    if (vch.size() <= 4)
        return strprintf("%d", CBigNum(vch).getint());
    else
        return HexStr(vch);
}

inline std::string StackString(const std::vector<std::vector<unsigned char> >& vStack)
{
    std::string str;
    BOOST_FOREACH(const std::vector<unsigned char>& vch, vStack)
    {
        if (!str.empty())
            str += " ";
        str += ValueString(vch);
    }
    return str;
}









class CScript : public std::vector<unsigned char>
{
protected:
    CScript& push_int64(int64 n)
    {
        if (n == -1 || (n >= 1 && n <= 16))
        {
            push_back(n + (OP_1 - 1));
        }
        else
        {
            CBigNum bn(n);
            *this << bn.getvch();
        }
        return *this;
    }

    CScript& push_uint64(uint64 n)
    {
        if (n >= 1 && n <= 16)
        {
            push_back(n + (OP_1 - 1));
        }
        else
        {
            CBigNum bn(n);
            *this << bn.getvch();
        }
        return *this;
    }

public:
    CScript() { }
    CScript(const CScript& b) : std::vector<unsigned char>(b.begin(), b.end()) { }
    CScript(const_iterator pbegin, const_iterator pend) : std::vector<unsigned char>(pbegin, pend) { }
#ifndef _MSC_VER
    CScript(const unsigned char* pbegin, const unsigned char* pend) : std::vector<unsigned char>(pbegin, pend) { }
#endif

    CScript& operator+=(const CScript& b)
    {
        insert(end(), b.begin(), b.end());
        return *this;
    }

    friend CScript operator+(const CScript& a, const CScript& b)
    {
        CScript ret = a;
        ret += b;
        return ret;
    }


    explicit CScript(char b)           { operator<<(b); }
    explicit CScript(short b)          { operator<<(b); }
    explicit CScript(int b)            { operator<<(b); }
    explicit CScript(long b)           { operator<<(b); }
    explicit CScript(int64 b)          { operator<<(b); }
    explicit CScript(unsigned char b)  { operator<<(b); }
    explicit CScript(unsigned int b)   { operator<<(b); }
    explicit CScript(unsigned short b) { operator<<(b); }
    explicit CScript(unsigned long b)  { operator<<(b); }
    explicit CScript(uint64 b)         { operator<<(b); }

    explicit CScript(opcodetype b)     { operator<<(b); }
    explicit CScript(const uint256& b) { operator<<(b); }
    explicit CScript(const CBigNum& b) { operator<<(b); }
    explicit CScript(const std::vector<unsigned char>& b) { operator<<(b); }


    CScript& operator<<(char b)           { return push_int64(b); }
    CScript& operator<<(short b)          { return push_int64(b); }
    CScript& operator<<(int b)            { return push_int64(b); }
    CScript& operator<<(long b)           { return push_int64(b); }
    CScript& operator<<(int64 b)          { return push_int64(b); }
    CScript& operator<<(unsigned char b)  { return push_uint64(b); }
    CScript& operator<<(unsigned int b)   { return push_uint64(b); }
    CScript& operator<<(unsigned short b) { return push_uint64(b); }
    CScript& operator<<(unsigned long b)  { return push_uint64(b); }
    CScript& operator<<(uint64 b)         { return push_uint64(b); }

    CScript& operator<<(opcodetype opcode)
    {
        if (opcode < 0 || opcode > 0xff)
            throw std::runtime_error("CScript::operator<<() : invalid opcode");
        insert(end(), (unsigned char)opcode);
        return *this;
    }

    CScript& operator<<(const uint160& b)
    {
        insert(end(), sizeof(b));
        insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b));
        return *this;
    }

    CScript& operator<<(const uint256& b)
    {
        insert(end(), sizeof(b));
        insert(end(), (unsigned char*)&b, (unsigned char*)&b + sizeof(b));
        return *this;
    }

    CScript& operator<<(const CBigNum& b)
    {
        *this << b.getvch();
        return *this;
    }

    CScript& operator<<(const std::vector<unsigned char>& b)
    {
        if (b.size() < OP_PUSHDATA1)
        {
            insert(end(), (unsigned char)b.size());
        }
        else if (b.size() <= 0xff)
        {
            insert(end(), OP_PUSHDATA1);
            insert(end(), (unsigned char)b.size());
        }
        else if (b.size() <= 0xffff)
        {
            insert(end(), OP_PUSHDATA2);
            unsigned short nSize = b.size();
            insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
        }
        else
        {
            insert(end(), OP_PUSHDATA4);
            unsigned int nSize = b.size();
            insert(end(), (unsigned char*)&nSize, (unsigned char*)&nSize + sizeof(nSize));
        }
        insert(end(), b.begin(), b.end());
        return *this;
    }

    CScript& operator<<(const CScript& b)
    {
        // I'm not sure if this should push the script or concatenate scripts.
        // If there's ever a use for pushing a script onto a script, delete this member fn
        assert(!"warning: pushing a CScript onto a CScript with << is probably not intended, use + to concatenate");
        return *this;
    }


    bool GetOp(iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet)
    {
         // Wrapper so it can be called with either iterator or const_iterator
         const_iterator pc2 = pc;
         bool fRet = GetOp2(pc2, opcodeRet, &vchRet);
         pc = begin() + (pc2 - begin());
         return fRet;
    }

    bool GetOp(iterator& pc, opcodetype& opcodeRet)
    {
         const_iterator pc2 = pc;
         bool fRet = GetOp2(pc2, opcodeRet, NULL);
         pc = begin() + (pc2 - begin());
         return fRet;
    }

    bool GetOp(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>& vchRet) const
    {
        return GetOp2(pc, opcodeRet, &vchRet);
    }

    bool GetOp(const_iterator& pc, opcodetype& opcodeRet) const
    {
        return GetOp2(pc, opcodeRet, NULL);
    }

    bool GetOp2(const_iterator& pc, opcodetype& opcodeRet, std::vector<unsigned char>* pvchRet) const
    {
        opcodeRet = OP_INVALIDOPCODE;
        if (pvchRet)
            pvchRet->clear();
        if (pc >= end())
            return false;

        // Read instruction
        if (end() - pc < 1)
            return false;
        unsigned int opcode = *pc++;

        // Immediate operand
        if (opcode <= OP_PUSHDATA4)
        {
            unsigned int nSize;
            if (opcode < OP_PUSHDATA1)
            {
                nSize = opcode;
            }
            else if (opcode == OP_PUSHDATA1)
            {
                if (end() - pc < 1)
                    return false;
                nSize = *pc++;
            }
            else if (opcode == OP_PUSHDATA2)
            {
                if (end() - pc < 2)
                    return false;
                nSize = 0;
                memcpy(&nSize, &pc[0], 2);
                pc += 2;
            }
            else if (opcode == OP_PUSHDATA4)
            {
                if (end() - pc < 4)
                    return false;
                memcpy(&nSize, &pc[0], 4);
                pc += 4;
            }
            if (end() - pc < nSize)
                return false;
            if (pvchRet)
                pvchRet->assign(pc, pc + nSize);
            pc += nSize;
        }

        opcodeRet = (opcodetype)opcode;
        return true;
    }


    void FindAndDelete(const CScript& b)
    {
        if (b.empty())
            return;
        iterator pc = begin();
        opcodetype opcode;
        do
        {
            while (end() - pc >= b.size() && memcmp(&pc[0], &b[0], b.size()) == 0)
                erase(pc, pc + b.size());
        }
        while (GetOp(pc, opcode));
    }


    int GetSigOpCount() const
    {
        int n = 0;
        const_iterator pc = begin();
        while (pc < end())
        {
            opcodetype opcode;
            if (!GetOp(pc, opcode))
                break;
            if (opcode == OP_CHECKSIG || opcode == OP_CHECKSIGVERIFY)
                n++;
            else if (opcode == OP_CHECKMULTISIG || opcode == OP_CHECKMULTISIGVERIFY)
                n += 20;
        }
        return n;
    }


    bool IsPushOnly() const
    {
        if (size() > 200)
            return false;
        const_iterator pc = begin();
        while (pc < end())
        {
            opcodetype opcode;
            if (!GetOp(pc, opcode))
                return false;
            if (opcode > OP_16)
                return false;
        }
        return true;
    }


    NewcoinAddress GetBitcoinAddress() const
    {
        opcodetype opcode;
        std::vector<unsigned char> vch;
        CScript::const_iterator pc = begin();
        if (!GetOp(pc, opcode, vch) || opcode != OP_DUP) return 0;
        if (!GetOp(pc, opcode, vch) || opcode != OP_HASH160) return 0;
        if (!GetOp(pc, opcode, vch) || vch.size() != sizeof(uint160)) return 0;
        uint160 hash160 = uint160(vch);
        if (!GetOp(pc, opcode, vch) || opcode != OP_EQUALVERIFY) return 0;
        if (!GetOp(pc, opcode, vch) || opcode != OP_CHECKSIG) return 0;
        if (pc != end()) return 0;
        return NewcoinAddress(hash160);
    }

    void SetBitcoinAddress(const NewcoinAddress& address)
    {
        this->clear();
        *this << OP_DUP << OP_HASH160 << address.GetHash160()) << OP_EQUALVERIFY << OP_CHECKSIG;
    }

    void SetBitcoinAddress(const std::vector<unsigned char>& vchPubKey)
    {
        SetBitcoinAddress(NewcoinAddress(vchPubKey));
    }


    void PrintHex() const
    {
        printf("CScript(%s)\n", HexStr(begin(), end(), true).c_str());
    }

    std::string ToString() const
    {
        std::string str;
        opcodetype opcode;
        std::vector<unsigned char> vch;
        const_iterator pc = begin();
        while (pc < end())
        {
            if (!str.empty())
                str += " ";
            if (!GetOp(pc, opcode, vch))
            {
                str += "[error]";
                return str;
            }
            if (0 <= opcode && opcode <= OP_PUSHDATA4)
                str += ValueString(vch);
            else
                str += GetOpName(opcode);
        }
        return str;
    }

    void print() const
    {
        printf("%s\n", ToString().c_str());
    }
};







bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType);

bool IsStandard(const CScript& scriptPubKey);
bool IsMine(const CKeyStore& keystore, const CScript& scriptPubKey);
bool ExtractAddress(const CScript& scriptPubKey, const CKeyStore* pkeystore, NewcoinAddress& addressRet);
bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL, CScript scriptPrereq=CScript());
bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, int nHashType=0);

#endif