//! Zebra supported RPC methods.
//!
//! Based on the [`zcashd` RPC methods](https://zcash.github.io/rpc/)
//! as used by `lightwalletd.`
//!
//! Some parts of the `zcashd` RPC documentation are outdated.
//! So this implementation follows the `lightwalletd` client implementation.

use jsonrpc_core::{self, Result};
use jsonrpc_derive::rpc;

use zebra_network::constants::USER_AGENT;

#[cfg(test)]
mod tests;

#[rpc(server)]
/// RPC method signatures.
pub trait Rpc {
    /// getinfo
    ///
    /// Returns software information from the RPC server running Zebra.
    ///
    /// zcashd reference: <https://zcash.github.io/rpc/getinfo.html>
    ///
    /// Result:
    /// {
    ///      "build": String, // Full application version
    ///      "subversion", String, // Zebra user agent
    /// }
    ///
    /// Note 1: We only expose 2 fields as they are the only ones needed for
    /// lightwalletd: <https://github.com/zcash/lightwalletd/blob/v0.4.9/common/common.go#L91-L95>
    ///
    /// Note 2: <https://zcash.github.io/rpc/getinfo.html> is outdated so it does not
    /// show the fields we are exposing. However, this fields are part of the output
    /// as shown in the following zcashd code:
    /// <https://github.com/zcash/zcash/blob/v4.6.0-1/src/rpc/misc.cpp#L86-L87>
    /// Zcash open ticket to add this fields to the docs: <https://github.com/zcash/zcash/issues/5606>
    #[rpc(name = "getinfo")]
    fn get_info(&self) -> Result<GetInfo>;

    /// getblockchaininfo
    ///
    /// TODO: explain what the method does
    ///       link to the zcashd RPC reference
    ///       list the arguments and fields that lightwalletd uses
    ///       note any other lightwalletd changes
    #[rpc(name = "getblockchaininfo")]
    fn get_blockchain_info(&self) -> Result<GetBlockChainInfo>;
}

/// RPC method implementations.

pub struct RpcImpl {
    /// Zebra's application version.
    pub app_version: String,
}
impl Rpc for RpcImpl {
    fn get_info(&self) -> Result<GetInfo> {
        let response = GetInfo {
            build: self.app_version.clone(),
            subversion: USER_AGENT.into(),
        };

        Ok(response)
    }

    fn get_blockchain_info(&self) -> Result<GetBlockChainInfo> {
        // TODO: dummy output data, fix in the context of #3143
        let response = GetBlockChainInfo {
            chain: "TODO: main".to_string(),
        };

        Ok(response)
    }
}

#[derive(serde::Serialize, serde::Deserialize)]
/// Response to a `getinfo` RPC request.
pub struct GetInfo {
    build: String,
    subversion: String,
}

#[derive(serde::Serialize, serde::Deserialize)]
/// Response to a `getblockchaininfo` RPC request.
pub struct GetBlockChainInfo {
    chain: String,
    // TODO: add other fields used by lightwalletd (#3143)
}