// Copyright 2020 MaidSafe.net limited.
//
// This SAFE Network Software is licensed to you under the MIT license <LICENSE-MIT
// http://opensource.org/licenses/MIT> or the Modified BSD license <LICENSE-BSD
// https://opensource.org/licenses/BSD-3-Clause>, at your option. This file may not be copied,
// modified, or distributed except according to those terms. Please review the Licences for the
// specific language governing permissions and limitations relating to use of the SAFE Network
// Software.

use super::{
    common::sk_from_hex,
    helpers::{parse_coins_amount, pk_from_hex, pk_to_hex, xorname_from_pk, KeyPair},
    xorurl::{SafeContentType, SafeDataType},
    Safe, SafeApp,
};
use crate::{
    xorurl::{XorUrl, XorUrlEncoder},
    Error, Result,
};
use rand_core::RngCore;
use safe_nd::{Coins, XorName};
use serde::{Deserialize, Serialize};
use threshold_crypto::{PublicKey, SecretKey};

// We expose a BLS key pair as two hex encoded strings
// TODO: consider supporting other encodings like base32 or just expose Vec<u8>
#[derive(Clone, Serialize, Deserialize)]
pub struct BlsKeyPair {
    pub pk: String,
    pub sk: String,
}

impl Safe {
    // Generate a key pair without creating and/or storing a SafeKey on the network
    pub fn keypair(&self) -> Result<BlsKeyPair> {
        let key_pair = KeyPair::random();
        let (pk, sk) = key_pair.to_hex_key_pair()?;
        Ok(BlsKeyPair { pk, sk })
    }

    // private helper
    async fn create_coin_balance(
        &mut self,
        from_sk: Option<SecretKey>,
        to_pk: PublicKey,
        amount: Coins,
    ) -> Result<XorName> {
        match self.safe_app.create_balance(from_sk, to_pk, amount).await {
            Err(Error::InvalidAmount(_)) => Err(Error::InvalidAmount(format!(
                "The amount '{}' specified for the transfer is invalid",
                amount
            ))),
            Err(Error::NotEnoughBalance(_)) => Err(Error::NotEnoughBalance(
                "Not enough balance at 'source' for the operation".to_string(),
            )),
            Err(other_error) => Err(Error::Unexpected(format!(
                "Unexpected error when attempting to create Key: {}",
                other_error
            ))),
            Ok(xorname) => Ok(xorname),
        }
    }

    // Create a SafeKey on the network and return its XOR-URL.
    pub async fn keys_create(
        &mut self,
        from: Option<&str>,
        preload_amount: Option<&str>,
        pk: Option<&str>,
    ) -> Result<(XorUrl, Option<BlsKeyPair>)> {
        let from_sk = match from {
            Some(sk) => match sk_from_hex(&sk) {
                Ok(sk) => Some(sk),
                Err(_) => return Err(Error::InvalidInput("The source of funds needs to be a secret key. The secret key provided is invalid".to_string())),
            },
            None => None,
        };

        let amount = parse_coins_amount(&preload_amount.unwrap_or_else(|| "0.0"))?;

        let (xorname, key_pair) = match pk {
            Some(pk_str) => {
                let pk = pk_from_hex(&pk_str)?;
                let xorname = self.create_coin_balance(from_sk, pk, amount).await?;
                (xorname, None)
            }
            None => {
                let key_pair = KeyPair::random();
                let (pk, sk) = key_pair.to_hex_key_pair()?;
                let xorname = self
                    .create_coin_balance(from_sk, key_pair.pk, amount)
                    .await?;
                (xorname, Some(BlsKeyPair { pk, sk }))
            }
        };

        let xorurl = XorUrlEncoder::encode_safekey(xorname, self.xorurl_base)?;
        Ok((xorurl, key_pair))
    }

    // Create a SafeKey on the network, allocates testcoins onto it, and return the SafeKey's XOR-URL
    pub async fn keys_create_preload_test_coins(
        &mut self,
        preload_amount: &str,
    ) -> Result<(XorUrl, Option<BlsKeyPair>)> {
        let amount = parse_coins_amount(preload_amount)?;
        let key_pair = KeyPair::random();
        let xorname = self
            .safe_app
            .allocate_test_coins(key_pair.sk.clone(), amount)
            .await?;
        let (pk, sk) = key_pair.to_hex_key_pair()?;
        let key_pair = Some(BlsKeyPair { pk, sk });

        let xorurl = XorUrlEncoder::encode_safekey(xorname, self.xorurl_base)?;
        Ok((xorurl, key_pair))
    }

    // Check SafeKey's balance from the network from a given SecretKey string
    pub async fn keys_balance_from_sk(&self, sk: &str) -> Result<String> {
        let secret_key = sk_from_hex(sk)?;
        let coins = self
            .safe_app
            .get_balance_from_sk(secret_key)
            .await
            .map_err(|_| {
                Error::ContentNotFound("No SafeKey found at specified location".to_string())
            })?;
        Ok(coins.to_string())
    }

    // Check SafeKey's balance from the network from a given XOR/NRS-URL and secret key string.
    // The difference between this and 'keys_balance_from_sk' function is that this will additionally
    // check that the XOR/NRS-URL corresponds to the public key derived from the provided secret key
    pub async fn keys_balance_from_url(&self, url: &str, sk: &str) -> Result<String> {
        self.validate_sk_for_url(sk, url).await?;
        self.keys_balance_from_sk(sk).await
    }

    // Check that the XOR/NRS-URL corresponds to the public key derived from the provided secret key
    pub async fn validate_sk_for_url(&self, sk: &str, url: &str) -> Result<String> {
        let secret_key: SecretKey = sk_from_hex(sk)
            .map_err(|_| Error::InvalidInput("Invalid secret key provided".to_string()))?;
        let (xorurl_encoder, _) = self.parse_and_resolve_url(url).await?;
        let public_key = secret_key.public_key();
        let derived_xorname = xorname_from_pk(public_key);
        if xorurl_encoder.xorname() != derived_xorname {
            Err(Error::InvalidInput(
                "The URL doesn't correspond to the public key derived from the provided secret key"
                    .to_string(),
            ))
        } else {
            Ok(pk_to_hex(&public_key))
        }
    }

    /// # Transfer safecoins from one SafeKey to another, or to a Wallet
    ///
    /// Using a secret key you can send safecoins to a Wallet or to a SafeKey.
    ///
    /// ## Example
    /// ```
    /// # use safe_api::Safe;
    /// let mut safe = Safe::default();
    /// # async_std::task::block_on(async {
    /// #   safe.connect("", Some("fake-credentials")).await.unwrap();
    ///     let (key1_xorurl, key_pair1) = safe.keys_create_preload_test_coins("14").await.unwrap();
    ///     let (key2_xorurl, key_pair2) = safe.keys_create_preload_test_coins("1").await.unwrap();
    ///     let current_balance = safe.keys_balance_from_sk(&key_pair1.clone().unwrap().sk).await.unwrap();
    ///     assert_eq!("14.000000000", current_balance);
    ///
    ///     safe.keys_transfer( "10", Some(&key_pair1.clone().unwrap().sk), &key2_xorurl, None ).await.unwrap();
    ///     let from_balance = safe.keys_balance_from_url( &key1_xorurl, &key_pair1.unwrap().sk ).await.unwrap();
    ///     assert_eq!("4.000000000", from_balance);
    ///     let to_balance = safe.keys_balance_from_url( &key2_xorurl, &key_pair2.unwrap().sk ).await.unwrap();
    ///     assert_eq!("11.000000000", to_balance);
    /// # });
    /// ```
    pub async fn keys_transfer(
        &mut self,
        amount: &str,
        from_sk: Option<&str>,
        to_url: &str,
        tx_id: Option<u64>,
    ) -> Result<u64> {
        // Parse and validate the amount is a valid
        let amount_coins = parse_coins_amount(amount)?;

        // Let's check if the 'to_url' is a valid Wallet or a SafeKey URL
        let (to_xorurl_encoder, _) = self.parse_and_resolve_url(to_url).await?;
        let to_xorname = if to_xorurl_encoder.content_type() == SafeContentType::Wallet {
            let (to_balance, _) = self
                .wallet_get_default_balance(&to_xorurl_encoder.to_string())
                .await?;
            XorUrlEncoder::from_url(&to_balance.xorurl)?.xorname()
        } else if to_xorurl_encoder.content_type() == SafeContentType::Raw
            && to_xorurl_encoder.data_type() == SafeDataType::SafeKey
        {
            to_xorurl_encoder.xorname()
        } else {
            return Err(Error::InvalidInput(format!(
                "The destination URL doesn't target a SafeKey or Wallet, target is: {:?} ({})",
                to_xorurl_encoder.content_type(),
                to_xorurl_encoder.data_type()
            )));
        };

        // Generate a random transfer TX ID
        let tx_id = tx_id.unwrap_or_else(|| rand::thread_rng().next_u64());

        let from = match &from_sk {
            Some(sk) => Some(sk_from_hex(sk)?),
            None => None,
        };

        // Finally, let's make the transfer
        match self
            .safe_app
            .safecoin_transfer_to_xorname(from, to_xorname, tx_id, amount_coins)
            .await
        {
            Err(Error::InvalidAmount(_)) => Err(Error::InvalidAmount(format!(
                "The amount '{}' specified for the transfer is invalid",
                amount
            ))),
            Err(Error::NotEnoughBalance(_)) => {
                let msg = if from_sk.is_some() {
                    "Not enough balance for the transfer at provided source SafeKey".to_string()
                } else {
                    "Not enough balance for the transfer at Account's default SafeKey".to_string()
                };

                Err(Error::NotEnoughBalance(msg))
            }
            Err(other_error) => Err(Error::Unexpected(format!(
                "Unexpected error when attempting to transfer: {}",
                other_error
            ))),
            Ok(tx) => Ok(tx.id),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::api::app::test_helpers::{new_safe_instance, random_nrs_name, unwrap_key_pair};

    #[tokio::test]
    async fn test_keys_create_preload_test_coins() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (xorurl, key_pair) = safe.keys_create_preload_test_coins("12.23").await?;
        assert!(xorurl.starts_with("safe://"));
        assert!(key_pair.is_some());
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_create() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_, from_key_pair) = safe.keys_create_preload_test_coins("23.23").await?;

        let (xorurl, key_pair) = safe
            .keys_create(Some(&unwrap_key_pair(from_key_pair)?.sk), None, None)
            .await?;
        assert!(xorurl.starts_with("safe://"));
        assert!(key_pair.is_some());
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_create_preload() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_, from_key_pair) = safe.keys_create_preload_test_coins("543.2312").await?;

        let preload_amount = "1.800000000";
        let (xorurl, key_pair) = safe
            .keys_create(
                Some(&unwrap_key_pair(from_key_pair)?.sk),
                Some(preload_amount),
                None,
            )
            .await?;
        assert!(xorurl.starts_with("safe://"));
        match key_pair {
            None => Err(Error::Unexpected(
                "Key pair was not generated as it was expected".to_string(),
            )),
            Some(kp) => {
                let balance = safe.keys_balance_from_sk(&kp.sk).await?;
                assert_eq!(balance, preload_amount);
                Ok(())
            }
        }
    }

    #[tokio::test]
    async fn test_keys_create_preload_invalid_amounts() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        match safe.keys_create_preload_test_coins(".45").await {
            Err(err) => assert_eq!(
                err,
                Error::InvalidAmount(
                    "Invalid safecoins amount '.45' (Can\'t parse coin units)".to_string()
                )
            ),
            Ok(_) => {
                return Err(Error::Unexpected(
                    "Key with test-coins was created unexpectedly".to_string(),
                ))
            }
        };

        let (_, kp) = safe.keys_create_preload_test_coins("12").await?;
        let mut key_pair = unwrap_key_pair(kp.clone())?;
        match safe
            .keys_create(Some(&key_pair.sk), Some(".003"), None)
            .await
        {
            Err(err) => assert_eq!(
                err,
                Error::InvalidAmount(
                    "Invalid safecoins amount '.003' (Can\'t parse coin units)".to_string()
                )
            ),
            Ok(_) => {
                return Err(Error::Unexpected(
                    "Key was created unexpectedly".to_string(),
                ))
            }
        };

        // test it fails with corrupted secret key
        key_pair.sk.replace_range(..6, "ababab");
        match safe
            .keys_create(Some(&key_pair.sk), Some(".003"), None)
            .await
        {
            Err(err) => assert_eq!(
                err,
                Error::InvalidAmount(
                    "Invalid safecoins amount '.003' (Can\'t parse coin units)".to_string()
                )
            ),
            Ok(_) => {
                return Err(Error::Unexpected(
                    "Key was created unexpectedly".to_string(),
                ))
            }
        };

        // test it fails to preload with more than available balance in source (which has only 12 coins)
        match safe
            .keys_create(Some(&unwrap_key_pair(kp)?.sk), Some("12.000000001"), None)
            .await
        {
            Err(err) => {
                assert_eq!(
                    err,
                    Error::NotEnoughBalance(
                        "Not enough balance at 'source' for the operation".to_string()
                    )
                );
                Ok(())
            }
            Ok(_) => Err(Error::Unexpected(
                "Key was created unexpectedly".to_string(),
            )),
        }
    }

    #[tokio::test]
    async fn test_keys_create_pk() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_, from_key_pair) = safe.keys_create_preload_test_coins("1.1").await?;
        let pk = pk_to_hex(&SecretKey::random().public_key());
        let (xorurl, key_pair) = safe
            .keys_create(Some(&unwrap_key_pair(from_key_pair)?.sk), None, Some(&pk))
            .await?;
        assert!(xorurl.starts_with("safe://"));
        assert!(key_pair.is_none());
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_test_coins_balance_pk() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let preload_amount = "1.154200000";
        let (_, key_pair) = safe.keys_create_preload_test_coins(preload_amount).await?;
        let current_balance = safe
            .keys_balance_from_sk(&unwrap_key_pair(key_pair)?.sk)
            .await?;
        assert_eq!(preload_amount, current_balance);
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_test_coins_balance_xorurl() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let preload_amount = "0.243000000";
        let (xorurl, key_pair) = safe.keys_create_preload_test_coins(preload_amount).await?;
        let current_balance = safe
            .keys_balance_from_url(&xorurl, &unwrap_key_pair(key_pair)?.sk)
            .await?;
        assert_eq!(preload_amount, current_balance);
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_test_coins_balance_wrong_url() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_xorurl, key_pair) = safe.keys_create_preload_test_coins("0").await?;

        let invalid_xorurl = "safe://this-is-not-a-valid-xor-url";
        let current_balance = safe
            .keys_balance_from_url(&invalid_xorurl, &unwrap_key_pair(key_pair)?.sk)
            .await;
        match current_balance {
            Err(Error::ContentNotFound(msg)) => {
                assert!(msg.contains(&format!("Content not found at {}", invalid_xorurl)));
                Ok(())
            }
            Err(err) => Err(Error::Unexpected(format!(
                "Error returned is not the expected: {:?}",
                err
            ))),
            Ok(balance) => Err(Error::Unexpected(format!(
                "Unexpected balance obtained: {:?}",
                balance
            ))),
        }
    }

    #[tokio::test]
    async fn test_keys_test_coins_balance_wrong_location() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let amount = "35312.000000000";
        let (xorurl, kp) = safe.keys_create_preload_test_coins(amount).await?;
        let key_pair = unwrap_key_pair(kp)?;

        let current_balance = safe.keys_balance_from_url(&xorurl, &key_pair.sk).await?;
        assert_eq!(amount, current_balance);

        // let's use the XOR-URL of another SafeKey
        let (other_kp_xorurl, _) = safe.keys_create_preload_test_coins("0").await?;
        let current_balance = safe
            .keys_balance_from_url(&other_kp_xorurl, &key_pair.sk)
            .await;
        match current_balance {
            Err(Error::InvalidInput(msg)) => {
                assert!(msg.contains(
                "The URL doesn't correspond to the public key derived from the provided secret key"
            ));
                Ok(())
            }
            Err(err) => Err(Error::Unexpected(format!(
                "Error returned is not the expected: {:?}",
                err
            ))),
            Ok(balance) => Err(Error::Unexpected(format!(
                "Unexpected balance obtained: {:?}",
                balance
            ))),
        }
    }

    #[tokio::test]
    async fn test_keys_test_coins_balance_wrong_sk() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_xorurl, kp) = safe.keys_create_preload_test_coins("0").await?;
        let mut sk = unwrap_key_pair(kp)?.sk;
        sk.replace_range(..6, "ababab");
        let current_balance = safe.keys_balance_from_sk(&sk).await;
        match current_balance {
            Err(Error::ContentNotFound(msg)) => {
                assert!(msg.contains("No SafeKey found at specified location"));
                Ok(())
            }
            Err(err) => Err(Error::Unexpected(format!(
                "Error returned is not the expected: {:?}",
                err
            ))),
            Ok(balance) => Err(Error::Unexpected(format!(
                "Unexpected balance obtained: {:?}",
                balance
            ))),
        }
    }

    #[tokio::test]
    async fn test_keys_balance_pk() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let preload_amount = "1743.234";
        let (_, from_kp) = safe.keys_create_preload_test_coins(preload_amount).await?;
        let from_key_pair = unwrap_key_pair(from_kp)?;

        let amount = "1740.000000000";
        let (_, to_key_pair) = safe
            .keys_create(Some(&from_key_pair.sk), Some(amount), None)
            .await?;

        let from_current_balance = safe.keys_balance_from_sk(&from_key_pair.sk).await?;
        assert_eq!(
            "3.233999999", /*== 1743.234 - 1740 - 0.000000001 (creation cost) */
            from_current_balance
        );

        let to_current_balance = safe
            .keys_balance_from_sk(&unwrap_key_pair(to_key_pair)?.sk)
            .await?;
        assert_eq!(amount, to_current_balance);
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_balance_xorname() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let preload_amount = "435.34";
        let (from_xorname, from_kp) = safe.keys_create_preload_test_coins(preload_amount).await?;
        let from_key_pair = unwrap_key_pair(from_kp)?;

        let amount = "35.300000000";
        let (to_xorname, to_key_pair) = safe
            .keys_create(Some(&from_key_pair.sk), Some(amount), None)
            .await?;

        let from_current_balance = safe
            .keys_balance_from_url(&from_xorname, &from_key_pair.sk)
            .await?;
        assert_eq!(
            "400.039999999", /*== 435.34 - 35.3 - 0.000000001 (creation cost)*/
            from_current_balance
        );

        let to_current_balance = safe
            .keys_balance_from_url(&to_xorname, &unwrap_key_pair(to_key_pair)?.sk)
            .await?;
        assert_eq!(amount, to_current_balance);
        Ok(())
    }

    #[tokio::test]
    async fn test_validate_sk_for_url() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (xorurl, kp) = safe.keys_create_preload_test_coins("23.22").await?;
        let key_pair = unwrap_key_pair(kp)?;
        let pk = safe.validate_sk_for_url(&key_pair.sk, &xorurl).await?;
        assert_eq!(pk, key_pair.pk);
        Ok(())
    }

    #[tokio::test]
    async fn test_keys_transfer_from_zero_balance() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_from_safekey_xorurl, key_pair1) = safe.keys_create_preload_test_coins("0.0").await?;
        let (to_safekey_xorurl, _key_pair2) = safe.keys_create_preload_test_coins("0.5").await?;

        // test it fails to transfer with 0 balance at SafeKey in <from> argument
        match safe
            .keys_transfer(
                "0",
                Some(&unwrap_key_pair(key_pair1)?.sk),
                &to_safekey_xorurl,
                None,
            )
            .await
        {
            Err(Error::InvalidAmount(msg)) => {
                assert_eq!(
                    msg,
                    "The amount '0' specified for the transfer is invalid".to_string()
                );
                Ok(())
            }
            Err(err) => Err(Error::Unexpected(format!(
                "Error returned is not the expected: {:?}",
                err
            ))),
            Ok(_) => Err(Error::Unexpected(
                "Transfer succeeded unexpectedly".to_string(),
            )),
        }
    }

    #[tokio::test]
    async fn test_keys_transfer_diff_amounts() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (safekey1_xorurl, kp1) = safe.keys_create_preload_test_coins("0.5").await?;
        let (safekey2_xorurl, kp2) = safe.keys_create_preload_test_coins("100.5").await?;

        // test it fails to transfer more than current balance at SafeKey in <from> argument
        let key_pair1 = unwrap_key_pair(kp1)?;
        match safe
            .keys_transfer("100.6", Some(&key_pair1.sk), &safekey2_xorurl, None)
            .await
        {
            Err(Error::NotEnoughBalance(msg)) => assert_eq!(
                msg,
                "Not enough balance for the transfer at provided source SafeKey".to_string()
            ),
            Err(err) => {
                return Err(Error::Unexpected(format!(
                    "Error returned is not the expected: {:?}",
                    err
                )))
            }
            Ok(_) => {
                return Err(Error::Unexpected(
                    "Transfer succeeded unexpectedly".to_string(),
                ))
            }
        };

        // test it fails to transfer as it's a invalid/non-numeric amount
        match safe
            .keys_transfer(".06", Some(&key_pair1.sk), &safekey2_xorurl, None)
            .await
        {
            Err(Error::InvalidAmount(msg)) => assert_eq!(
                msg,
                "Invalid safecoins amount '.06' (Can\'t parse coin units)"
            ),
            Err(err) => {
                return Err(Error::Unexpected(format!(
                    "Error returned is not the expected: {:?}",
                    err
                )))
            }
            Ok(_) => {
                return Err(Error::Unexpected(
                    "Transfer succeeded unexpectedly".to_string(),
                ))
            }
        };

        // test it fails to transfer less than 1 nano coin
        let key_pair2 = unwrap_key_pair(kp2)?;
        match safe.keys_transfer(
                "0.0000000009",
                Some(&key_pair2.sk),
                &safekey2_xorurl,
                None
            ).await {
                    Err(Error::InvalidAmount(msg)) => assert_eq!(msg, "Invalid safecoins amount '0.0000000009', the minimum possible amount is one nano coin (0.000000001)"),
                    Err(err) => return Err(Error::Unexpected(format!("Error returned is not the expected: {:?}", err))),
                    Ok(_) => return Err(Error::Unexpected("Transfer succeeded unexpectedly".to_string())),
            };

        // test successful transfer
        match safe
            .keys_transfer("100.4", Some(&key_pair2.sk), &safekey1_xorurl, None)
            .await
        {
            Err(msg) => Err(Error::Unexpected(format!(
                "Transfer was expected to succeed: {}",
                msg
            ))),
            Ok(_) => {
                let from_current_balance = safe.keys_balance_from_sk(&key_pair2.sk).await?;
                assert_eq!("0.100000000", from_current_balance);
                let to_current_balance = safe.keys_balance_from_sk(&key_pair1.sk).await?;
                assert_eq!("100.900000000", to_current_balance);
                Ok(())
            }
        }
    }

    #[tokio::test]
    async fn test_keys_transfer_to_wallet() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let to_wallet_xorurl = safe.wallet_create().await?;
        let (_, kp1) = safe.keys_create_preload_test_coins("10.0").await?;
        let key_pair1 = unwrap_key_pair(kp1)?;
        safe.wallet_insert(
            &to_wallet_xorurl,
            Some("my-first-balance"),
            true, // set --default
            &key_pair1.sk,
        )
        .await?;

        let (_safekey_xorurl, kp2) = safe.keys_create_preload_test_coins("4621.45").await?;

        // test successful transfer
        let key_pair2 = unwrap_key_pair(kp2)?;
        match safe
            .keys_transfer(
                "523.87",
                Some(&key_pair2.sk),
                &to_wallet_xorurl.clone(),
                None,
            )
            .await
        {
            Err(msg) => Err(Error::Unexpected(format!(
                "Transfer was expected to succeed: {}",
                msg
            ))),
            Ok(_) => {
                let from_current_balance = safe.keys_balance_from_sk(&key_pair2.sk).await?;
                assert_eq!(
                    "4097.580000000", /* 4621.45 - 523.87 */
                    from_current_balance
                );
                let wallet_current_balance = safe.wallet_balance(&to_wallet_xorurl).await?;
                assert_eq!("533.870000000", wallet_current_balance);
                Ok(())
            }
        }
    }

    #[tokio::test]
    async fn test_keys_transfer_to_nrs_urls() -> Result<()> {
        let mut safe = new_safe_instance().await?;
        let (_from_safekey_xorurl, kp1) = safe.keys_create_preload_test_coins("0.2").await?;
        let (to_safekey_xorurl, kp2) = safe.keys_create_preload_test_coins("0.1").await?;
        let key_pair1 = unwrap_key_pair(kp1)?;
        let key_pair2 = unwrap_key_pair(kp2)?;

        let to_nrsurl = random_nrs_name();
        let _ = safe
            .nrs_map_container_create(&to_nrsurl, &to_safekey_xorurl, false, true, false)
            .await?;

        // test successful transfer
        match safe
            .keys_transfer("0.2", Some(&key_pair1.sk), &to_nrsurl, None)
            .await
        {
            Err(msg) => Err(Error::Unexpected(format!(
                "Transfer was expected to succeed: {}",
                msg
            ))),
            Ok(_) => {
                let from_current_balance = safe.keys_balance_from_sk(&key_pair1.sk).await?;
                assert_eq!("0.000000000" /* 0.2 - 0.2 */, from_current_balance);
                let to_current_balance = safe.keys_balance_from_sk(&key_pair2.sk).await?;
                assert_eq!("0.300000000" /* 0.1 + 0.2 */, to_current_balance);
                Ok(())
            }
        }
    }
}