Mecenas CashScript Contract for recurring payments. More info: https://www.reddit.com/r/btc/comments/cuzi1o/mecenas_recurring_payment_smart_contract_since_we/. More info about CashScript: https://developer.bitcoin.com/cashscript/docs/language

Mecenas.cash

contract Mecenas(bytes20 pkh, bytes20 pkh2, int pledge) {
  function protege(pubkey pk, sig s, bytes ver, bytes hPhSo, bytes scriptCode, bytes value, bytes nSequence, bytes hashOutput, bytes tail ) {
    require(ver.length == 4);
    require(hPhSo.length == 100);
    require(value.length == 8);
    require(nSequence.length == 4);
    require(nSequence.length == 32);
    require(tail.length == 8);
    require(checkSig(s, pk));
    bytes preimage = ver + hPhSo + scriptCode + value + nSequence + hashOutput + tail;
    require(checkDataSig(datasig(s), sha256(preimage), pk));
    int fee = 1000;
    // num2bin?
    bytes amount2 = bytes(pledge);
    bytes amount1 = bytes(int(value) - pledge - fee);

    bytes opDup = 0x76;
    bytes opEqual = 0x87;
    bytes opHash160 = 0xa9;
    bytes pushHash = 0x14;
    bytes newVarInt1 = 0x17;
    bytes newVarInt2 = 0x19;
    bytes opEqualverify = 0x88;
    bytes opChecksig = 0xac;

    // original spedn
    // bin [_, rawscr] = scriptCode @ 3;
    // is this split correctly?
    bytes rawscr = scriptCode.split(3)[0];

    // how to check for 30 days?
    require(tx.time >= 30);
    require(int(ver) >= 2);

    bytes out1 = amount1 + newVarInt1 + opHash160 + pushHash + hash160(rawscr) + opEqual;
    bytes out2 = amount2 + newVarInt2 + opDup + opHash160 + pushHash + pkh + opEqualverify + opChecksig;
    require(hash256(out1 + out2) == sha256(hashOutput)); 
    } 

  function mecenas(pubkey pk, sig s) {
    require(hash160(pk) == pkh2);
    require(checkSig(s, pk));
  }
}