// ==========================================================================================================
// *** RELAY POLICY FILTER ***
// Place in /policy/policy.cpp, and call from within IsStandardTx() before returning:
//     if (IsBulkDust(tx, reason))
//         return false;   // reject as nonstandard
// ==========================================================================================================

bool IsBulkDust(const CTransaction& tx, std::string& reason)
{
    static constexpr CAmount MIN_OUTPUT_VALUE_SATS = 1000;   // < 1000 sats counts as "tiny"
    static constexpr int     MAX_TINY_OUTPUTS      = 100;    // >= 100 tiny outputs triggers ratio check
    static constexpr double  TINY_RATIO_THRESHOLD  = 0.6;    // >= 60% of all outputs tiny = reject

    int tiny = 0;
    const int total = tx.vout.size();

    // Sanity check — avoid division by zero
    if (total == 0)
        return false;

    // Count any spendable output under 1000 sats as "tiny"
    for (const auto& out : tx.vout) {
        if (out.nValue < MIN_OUTPUT_VALUE_SATS)
            ++tiny;
    }

    // Threshold + ratio check
    if (tiny >= MAX_TINY_OUTPUTS && (static_cast<double>(tiny) / total) >= TINY_RATIO_THRESHOLD)
    {
        reason = strprintf("too-many-tiny-outputs(%d of %d, %.2f%%)", tiny, total, 100.0 * tiny / total);
        return true;  // flag as bulk dust
    }

    return false;
}


// ==========================================================================================================
// *** CONSENSUS (soft-fork, hybrid activation) ***
// Helpers in /consensus/tx_check.cpp; activation/enforcement in /validation.cpp
// Also define deployment in: /consensus/params.h, /chainparams.cpp, /versionbits.*
// ==========================================================================================================

// -----------------------------------------------------------------------
// --- In /consensus/tx_check.cpp (helper only; no params needed) ---
// -----------------------------------------------------------------------

static constexpr CAmount MIN_OUTPUT_VALUE_SATS = 1000;   // < 1000 sats counts as "tiny"
static constexpr int     MAX_TINY_OUTPUTS      = 100;    // >= 100 tiny outputs triggers ratio check
static constexpr double  TINY_RATIO_THRESHOLD  = 0.6;    // >= 60% of all outputs tiny = reject

bool IsBulkDust(const CTransaction& tx)    // expose via tx_check.h if needed
{
    int tiny = 0;
    const int total = tx.vout.size();

    // Sanity check — avoid division by zero
    if (total == 0)
        return false;

    // Count any spendable output under 1000 sats as "tiny"
    for (const auto& out : tx.vout) {
        if (out.nValue < MIN_OUTPUT_VALUE_SATS)
            ++tiny;
    }

    // Threshold + ratio check
    if (tiny >= MAX_TINY_OUTPUTS && ((static_cast<double>(tiny) / total) >= TINY_RATIO_THRESHOLD))
        return true;

    return false;
}


// -----------------------------------------------------------------------
// --- In /validation.cpp (enforcement with hybrid activation) ---
// -----------------------------------------------------------------------

#include <consensus/tx_check.h>
#include <versionbits.h>

// ... inside the appropriate validation path (e.g., after basic tx checks),
// with access to chainparams/params and a tip pointer:

const Consensus::Params& params = chainparams.GetConsensus();

const bool bulk_dust_active =
    DeploymentActiveAtTip(params, Consensus::DEPLOYMENT_BULK_DUST_LIMIT) ||
    (chainActive.Tip() && chainActive.Tip()->nHeight >= params.BulkDustActivationHeight);

if (bulk_dust_active) {
    if (IsBulkDust(tx)) {
        return state.Invalid(TxValidationResult::TX_CONSENSUS, "too-many-tiny-outputs");
    }
}


// -----------------------------------------------------------------------
// --- In /consensus/params.h ---
// -----------------------------------------------------------------------

enum DeploymentPos {
    // ...
    DEPLOYMENT_BULK_DUST_LIMIT,
    MAX_VERSION_BITS_DEPLOYMENTS
};

struct Params {
    // ...
    int BulkDustActivationHeight; // height flag-day fallback
};


// -----------------------------------------------------------------------
// --- In /chainparams.cpp (per-network values; examples only) ---
// -----------------------------------------------------------------------

consensus.vDeployments[Consensus::DEPLOYMENT_BULK_DUST_LIMIT].bit = 12;
consensus.vDeployments[Consensus::DEPLOYMENT_BULK_DUST_LIMIT].nStartTime = 1767225600;  // 2026-01-01 UTC
consensus.vDeployments[Consensus::DEPLOYMENT_BULK_DUST_LIMIT].nTimeout   = 1838160000;  // 2028-04-01 UTC
consensus.vDeployments[Consensus::DEPLOYMENT_BULK_DUST_LIMIT].min_activation_height = 969696;

consensus.BulkDustActivationHeight = 1021021;  // flag-day fallback