/*
 * This file is part of the Flowee project
 * Copyright (C) 2009-2010 Satoshi Nakamoto
 * Copyright (C) 2009-2015 The Bitcoin developers
 * Copyright (C) 2019-2021 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef FLOWEE_POLICY_POLICY_H
#define FLOWEE_POLICY_POLICY_H

#include "consensus/consensus.h"
#include "script/interpreter.h"
#include "script/standard.h"

#include <string>

class Tx;
class UnspentOutputDatabase;

/** The maximum size for transactions we're willing to relay/mine */
static const unsigned int MAX_STANDARD_TX_SIZE = 100000;

/**
 * Standard script verification flags that standard transactions will comply
 * with. However scripts violating these flags may still be present in valid
 * blocks and we must accept those blocks.
 */
static const unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS |
                                                         SCRIPT_VERIFY_DERSIG |
                                                         SCRIPT_VERIFY_STRICTENC |
                                                         SCRIPT_VERIFY_MINIMALDATA |
                                                         SCRIPT_VERIFY_NULLDUMMY |
                                                         SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS |
                                                         SCRIPT_VERIFY_CLEANSTACK |
                                                         SCRIPT_VERIFY_NULLFAIL |
                                                         SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY |
                                                         SCRIPT_VERIFY_CHECKSEQUENCEVERIFY |
                                                         SCRIPT_VERIFY_LOW_S;

/** For convenience, standard but not mandatory verify flags. */
static const unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS;

/** Used as the flags parameter to sequence and nLocktime checks in non-consensus code. */
static const unsigned int STANDARD_LOCKTIME_VERIFY_FLAGS = LOCKTIME_VERIFY_SEQUENCE |
                                                           LOCKTIME_MEDIAN_TIME_PAST;

/// \internal. Only here for unit tests.
bool IsStandard(const CScript &scriptPubKey, Script::TxnOutType &whichType, int &dataUsed);
    /**
     * Check for standard transaction types
     * @return True if all outputs (scriptPubKeys) use only standard transaction forms
     */
bool IsStandardTx(const CTransaction& tx, std::string& reason);

namespace Policy {
    constexpr unsigned int MAX_SIGCHEKCS_PER_TX = 3000;

    std::int32_t blockSizeAcceptLimit();
    uint32_t blockSigCheckAcceptLimit();
    /**
     * Check for standard transaction types
     * @return True if input use standard transaction forms
     */
    bool isInputStandard(const CScript &outputScript, const CScript &inputScript);
    /**
     * Check for standard transaction types
     * @return True if all inputs use only standard transaction forms
     */
    bool areInputsStandard(const Tx &tx, const UnspentOutputDatabase *utxo);
}

#endif