// Copyright (c) 2019-2020 The Zcash developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or https://www.opensource.org/licenses/mit-license.php .

syntax = "proto3";
package cash.z.wallet.sdk.rpc;
option go_package = "lightwalletd/walletrpc";
option swift_prefix = "";
import "compact_formats.proto";

// A BlockID message contains identifiers to select a block: a height or a
// hash. Specification by hash is not implemented, but may be in the future.
message BlockID {
     uint64 height = 1;
     bytes hash = 2;
}

// BlockRange specifies a series of blocks from start to end inclusive.
// Both BlockIDs must be heights; specification by hash is not yet supported.
message BlockRange {
    BlockID start = 1;
    BlockID end = 2;
    uint64 spamFilterThreshold = 3;
}

// A TxFilter contains the information needed to identify a particular
// transaction: either a block and an index, or a direct transaction hash.
// Currently, only specification by hash is supported.
message TxFilter {
     BlockID block = 1;     // block identifier, height or hash
     uint64 index = 2;      // index within the block
     bytes hash = 3;        // transaction ID (hash, txid)
}

// RawTransaction contains the complete transaction data. It also optionally includes 
// the block height in which the transaction was included, or, when returned
// by GetMempoolStream(), the latest block height.
message RawTransaction {
    bytes data = 1;     // exact data returned by Zcash 'getrawtransaction'
    uint64 height = 2;  // height that the transaction was mined (or -1)
}

// A SendResponse encodes an error code and a string. It is currently used
// only by SendTransaction(). If error code is zero, the operation was
// successful; if non-zero, it and the message specify the failure.
message SendResponse {
    int32 errorCode = 1;
    string errorMessage = 2;
}

// Chainspec is a placeholder to allow specification of a particular chain fork.
message ChainSpec {}

// Empty is for gRPCs that take no arguments, currently only GetLightdInfo.
message Empty {}

// LightdInfo returns various information about this lightwalletd instance
// and the state of the blockchain.
message LightdInfo {
    string version = 1;
    string vendor = 2;
    bool   taddrSupport = 3;            // true
    string chainName = 4;               // either "main" or "test"
    uint64 saplingActivationHeight = 5; // depends on mainnet or testnet
    string consensusBranchId = 6;       // protocol identifier, see consensus/upgrades.cpp
    uint64 blockHeight = 7;             // latest block on the best chain
    string gitCommit = 8;
    string branch = 9;
    string buildDate = 10;
    string buildUser = 11;
    uint64 estimatedHeight = 12;        // less than tip height if zcashd is syncing
    string zcashdBuild = 13;            // example: "v4.1.1-877212414"
    string zcashdSubversion = 14;       // example: "/MagicBean:4.1.1/"
}

// TransparentAddressBlockFilter restricts the results to the given address
// or block range.
message TransparentAddressBlockFilter {
    string address = 1;     // t-address
    BlockRange range = 2;   // start, end heights
}

// Duration is currently used only for testing, so that the Ping rpc
// can simulate a delay, to create many simultaneous connections. Units
// are microseconds.
message Duration {
    int64 intervalUs = 1;
}

// PingResponse is used to indicate concurrency, how many Ping rpcs
// are executing upon entry and upon exit (after the delay).
// This rpc is used for testing only.
message PingResponse {
    int64 entry = 1;
    int64 exit = 2;
}

message Address {
    string address = 1;
}
message AddressList {
    repeated string addresses = 1;
}
message Balance {
    int64 valueZat = 1;
}

message Exclude {
    repeated bytes txid = 1;
}

// The TreeState is derived from the Zcash z_gettreestate rpc.
message TreeState {
    string network = 1;     // "main" or "test"
    uint64 height = 2;      // block height
    string hash = 3;        // block id
    uint32 time = 4;        // Unix epoch time when the block was mined
    string saplingTree = 5; // sapling commitment tree state
    string orchardTree = 6; // orchard commitment tree state
}

// Results are sorted by height, which makes it easy to issue another
// request that picks up from where the previous left off.
message GetAddressUtxosArg {
    repeated string addresses = 1;
    uint64 startHeight = 2;
    uint32 maxEntries = 3; // zero means unlimited
}
message GetAddressUtxosReply {
    string address = 6;
    bytes txid = 1;
    int32 index = 2;
    bytes script = 3;
    int64 valueZat = 4;
    uint64 height = 5;
}
message GetAddressUtxosReplyList {
    repeated GetAddressUtxosReply addressUtxos = 1;
}

service CompactTxStreamer {
    // Return the height of the tip of the best chain
    rpc GetLatestBlock(ChainSpec) returns (BlockID) {}
    // Return the compact block corresponding to the given block identifier
    rpc GetBlock(BlockID) returns (CompactBlock) {}
    // Return a list of consecutive compact blocks
    rpc GetBlockRange(BlockRange) returns (stream CompactBlock) {}

    // Return the requested full (not compact) transaction (as from zcashd)
    rpc GetTransaction(TxFilter) returns (RawTransaction) {}
    // Submit the given transaction to the Zcash network
    rpc SendTransaction(RawTransaction) returns (SendResponse) {}

    // Return the txids corresponding to the given t-address within the given block range
    rpc GetTaddressTxids(TransparentAddressBlockFilter) returns (stream RawTransaction) {}
    rpc GetTaddressBalance(AddressList) returns (Balance) {}
    rpc GetTaddressBalanceStream(stream Address) returns (Balance) {}

    // Return the compact transactions currently in the mempool; the results
    // can be a few seconds out of date. If the Exclude list is empty, return
    // all transactions; otherwise return all *except* those in the Exclude list
    // (if any); this allows the client to avoid receiving transactions that it
    // already has (from an earlier call to this rpc). The transaction IDs in the
    // Exclude list can be shortened to any number of bytes to make the request
    // more bandwidth-efficient; if two or more transactions in the mempool
    // match a shortened txid, they are all sent (none is excluded). Transactions
    // in the exclude list that don't exist in the mempool are ignored.
    rpc GetMempoolTx(Exclude) returns (stream CompactTx) {}

    // Return a stream of current Mempool transactions. This will keep the output stream open while
    // there are mempool transactions. It will close the returned stream when a new block is mined.
    rpc GetMempoolStream(Empty) returns (stream RawTransaction) {}

    // GetTreeState returns the note commitment tree state corresponding to the given block.
    // See section 3.7 of the Zcash protocol specification. It returns several other useful
    // values also (even though they can be obtained using GetBlock).
    // The block can be specified by either height or hash.
    rpc GetTreeState(BlockID) returns (TreeState) {}

    rpc GetAddressUtxos(GetAddressUtxosArg) returns (GetAddressUtxosReplyList) {}
    rpc GetAddressUtxosStream(GetAddressUtxosArg) returns (stream GetAddressUtxosReply) {}

    // Return information about this lightwalletd instance and the blockchain
    rpc GetLightdInfo(Empty) returns (LightdInfo) {}
    // Testing-only, requires lightwalletd --ping-very-insecure (do not enable in production)
    rpc Ping(Duration) returns (PingResponse) {}
}