// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity Ethereum.

// Parity Ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Parity Ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Parity Ethereum.  If not, see <http://www.gnu.org/licenses/>.

//! Single account in the system.

use bytes::{Bytes, ToPretty};
use error::Error;
use ethereum_types::{Address, H256, U256};
use ethtrie::{Result as TrieResult, SecTrieDB, TrieDB, TrieFactory};
use hash::{keccak, KECCAK_EMPTY, KECCAK_NULL_RLP};
use hash_db::HashDB;
use keccak_hasher::KeccakHasher;
use kvdb::DBValue;
use lru_cache::LruCache;
use pod_account::*;
use rlp::{encode, RlpStream};
use std::{
    collections::{BTreeMap, HashMap},
    fmt,
    sync::Arc,
};
use trie::{Recorder, Trie};
use types::basic_account::BasicAccount;

use std::cell::{Cell, RefCell};

const STORAGE_CACHE_ITEMS: usize = 8192;

/// Boolean type for clean/dirty status.
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub enum Filth {
    /// Data has not been changed.
    Clean,
    /// Data has been changed.
    Dirty,
}

/// Single account in the system.
/// Keeps track of changes to the code and storage.
/// The changes are applied in `commit_storage` and `commit_code`
pub struct Account {
    // Balance of the account.
    balance: U256,
    // Nonce of the account.
    nonce: U256,
    // Trie-backed storage.
    storage_root: H256,
    // LRU Cache of the trie-backed storage.
    // This is limited to `STORAGE_CACHE_ITEMS` recent queries
    storage_cache: RefCell<LruCache<H256, H256>>,
    // LRU Cache of the trie-backed storage for original value.
    // This is only used when the initial storage root is different compared to
    // what is in the database. That is, it is only used for new contracts.
    original_storage_cache: Option<(H256, RefCell<LruCache<H256, H256>>)>,
    // Modified storage. Accumulates changes to storage made in `set_storage`
    // Takes precedence over `storage_cache`.
    storage_changes: HashMap<H256, H256>,
    // Code hash of the account.
    code_hash: H256,
    // Size of the account code.
    code_size: Option<usize>,
    // Code cache of the account.
    code_cache: Arc<Bytes>,
    // Account code new or has been modified.
    code_filth: Filth,
    // Cached address hash.
    address_hash: Cell<Option<H256>>,
}

impl From<BasicAccount> for Account {
    fn from(basic: BasicAccount) -> Self {
        Account {
            balance: basic.balance,
            nonce: basic.nonce,
            storage_root: basic.storage_root,
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: None,
            storage_changes: HashMap::new(),
            code_hash: basic.code_hash,
            code_size: None,
            code_cache: Arc::new(vec![]),
            code_filth: Filth::Clean,
            address_hash: Cell::new(None),
        }
    }
}

impl Account {
    #[cfg(test)]
    /// General constructor.
    pub fn new(balance: U256, nonce: U256, storage: HashMap<H256, H256>, code: Bytes) -> Account {
        Account {
            balance: balance,
            nonce: nonce,
            storage_root: KECCAK_NULL_RLP,
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: None,
            storage_changes: storage,
            code_hash: keccak(&code),
            code_size: Some(code.len()),
            code_cache: Arc::new(code),
            code_filth: Filth::Dirty,
            address_hash: Cell::new(None),
        }
    }

    fn empty_storage_cache() -> RefCell<LruCache<H256, H256>> {
        RefCell::new(LruCache::new(STORAGE_CACHE_ITEMS))
    }

    /// General constructor.
    pub fn from_pod(pod: PodAccount) -> Account {
        Account {
            balance: pod.balance,
            nonce: pod.nonce,
            storage_root: KECCAK_NULL_RLP,
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: None,
            storage_changes: pod.storage.into_iter().collect(),
            code_hash: pod.code.as_ref().map_or(KECCAK_EMPTY, |c| keccak(c)),
            code_filth: Filth::Dirty,
            code_size: Some(pod.code.as_ref().map_or(0, |c| c.len())),
            code_cache: Arc::new(pod.code.map_or_else(
                || {
                    warn!("POD account with unknown code is being created! Assuming no code.");
                    vec![]
                },
                |c| c,
            )),
            address_hash: Cell::new(None),
        }
    }

    /// Create a new account with the given balance.
    pub fn new_basic(balance: U256, nonce: U256) -> Account {
        Account {
            balance: balance,
            nonce: nonce,
            storage_root: KECCAK_NULL_RLP,
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: None,
            storage_changes: HashMap::new(),
            code_hash: KECCAK_EMPTY,
            code_cache: Arc::new(vec![]),
            code_size: Some(0),
            code_filth: Filth::Clean,
            address_hash: Cell::new(None),
        }
    }

    /// Create a new account from RLP.
    pub fn from_rlp(rlp: &[u8]) -> Result<Account, Error> {
        ::rlp::decode::<BasicAccount>(rlp)
            .map(|ba| ba.into())
            .map_err(|e| e.into())
    }

    /// Create a new contract account.
    /// NOTE: make sure you use `init_code` on this before `commit`ing.
    pub fn new_contract(balance: U256, nonce: U256, original_storage_root: H256) -> Account {
        Account {
            balance: balance,
            nonce: nonce,
            storage_root: KECCAK_NULL_RLP,
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: if original_storage_root == KECCAK_NULL_RLP {
                None
            } else {
                Some((original_storage_root, Self::empty_storage_cache()))
            },
            storage_changes: HashMap::new(),
            code_hash: KECCAK_EMPTY,
            code_cache: Arc::new(vec![]),
            code_size: None,
            code_filth: Filth::Clean,
            address_hash: Cell::new(None),
        }
    }

    /// Set this account's code to the given code.
    /// NOTE: Account should have been created with `new_contract()`
    pub fn init_code(&mut self, code: Bytes) {
        self.code_hash = keccak(&code);
        self.code_cache = Arc::new(code);
        self.code_size = Some(self.code_cache.len());
        self.code_filth = Filth::Dirty;
    }

    /// Reset this account's code to the given code.
    pub fn reset_code(&mut self, code: Bytes) {
        self.init_code(code);
    }

    /// Reset this account's code and storage to given values.
    pub fn reset_code_and_storage(&mut self, code: Arc<Bytes>, storage: HashMap<H256, H256>) {
        self.code_hash = keccak(&*code);
        self.code_cache = code;
        self.code_size = Some(self.code_cache.len());
        self.code_filth = Filth::Dirty;
        self.storage_cache = Self::empty_storage_cache();
        self.storage_changes = storage;
        if self.storage_root != KECCAK_NULL_RLP {
            self.original_storage_cache = Some((self.storage_root, Self::empty_storage_cache()));
        }
        self.storage_root = KECCAK_NULL_RLP;
    }

    /// Set (and cache) the contents of the trie's storage at `key` to `value`.
    pub fn set_storage(&mut self, key: H256, value: H256) {
        self.storage_changes.insert(key, value);
    }

    /// Get (and cache) the contents of the trie's storage at `key`.
    /// Takes modified storage into account.
    pub fn storage_at(&self, db: &HashDB<KeccakHasher, DBValue>, key: &H256) -> TrieResult<H256> {
        if let Some(value) = self.cached_storage_at(key) {
            return Ok(value);
        }
        Self::get_and_cache_storage(
            &self.storage_root,
            &mut self.storage_cache.borrow_mut(),
            db,
            key,
        )
    }

    /// Get (and cache) the contents of the trie's storage at `key`.
    /// Does not take modified storage into account.
    pub fn original_storage_at(
        &self,
        db: &HashDB<KeccakHasher, DBValue>,
        key: &H256,
    ) -> TrieResult<H256> {
        if let Some(value) = self.cached_original_storage_at(key) {
            return Ok(value);
        }
        match &self.original_storage_cache {
            Some((ref original_storage_root, ref original_storage_cache)) => {
                Self::get_and_cache_storage(
                    original_storage_root,
                    &mut original_storage_cache.borrow_mut(),
                    db,
                    key,
                )
            }
            None => Self::get_and_cache_storage(
                &self.storage_root,
                &mut self.storage_cache.borrow_mut(),
                db,
                key,
            ),
        }
    }

    fn get_and_cache_storage(
        storage_root: &H256,
        storage_cache: &mut LruCache<H256, H256>,
        db: &HashDB<KeccakHasher, DBValue>,
        key: &H256,
    ) -> TrieResult<H256> {
        let db = SecTrieDB::new(&db, storage_root)?;
        let panicky_decoder =
            |bytes: &[u8]| ::rlp::decode(&bytes).expect("decoding db value failed");
        let item: U256 = db
            .get_with(key, panicky_decoder)?
            .unwrap_or_else(U256::zero);
        let value: H256 = item.into();
        storage_cache.insert(key.clone(), value.clone());
        Ok(value)
    }

    /// Get cached storage value if any. Returns `None` if the
    /// key is not in the cache.
    pub fn cached_storage_at(&self, key: &H256) -> Option<H256> {
        if let Some(value) = self.storage_changes.get(key) {
            return Some(value.clone());
        }
        self.cached_moved_original_storage_at(key)
    }

    /// Get cached original storage value after last state commitment. Returns `None` if the key is not in the cache.
    pub fn cached_original_storage_at(&self, key: &H256) -> Option<H256> {
        match &self.original_storage_cache {
            Some((_, ref original_storage_cache)) => {
                if let Some(value) = original_storage_cache.borrow_mut().get_mut(key) {
                    Some(value.clone())
                } else {
                    None
                }
            }
            None => self.cached_moved_original_storage_at(key),
        }
    }

    /// Get cached original storage value since last contract creation on this address. Returns `None` if the key is not in the cache.
    fn cached_moved_original_storage_at(&self, key: &H256) -> Option<H256> {
        // If storage root is empty RLP, then early return zero value. Practically, this makes it so that if
        // `original_storage_cache` is used, then `storage_cache` will always remain empty.
        if self.storage_root == KECCAK_NULL_RLP {
            return Some(H256::new());
        }

        if let Some(value) = self.storage_cache.borrow_mut().get_mut(key) {
            Some(value.clone())
        } else {
            None
        }
    }

    /// return the balance associated with this account.
    pub fn balance(&self) -> &U256 {
        &self.balance
    }

    /// return the nonce associated with this account.
    pub fn nonce(&self) -> &U256 {
        &self.nonce
    }

    /// return the code hash associated with this account.
    pub fn code_hash(&self) -> H256 {
        self.code_hash.clone()
    }

    /// return and cache `keccak(address)`, `address` must be the address of this
    /// account.
    pub fn address_hash(&self, address: &Address) -> H256 {
        let hash = self.address_hash.get();
        hash.unwrap_or_else(|| {
            let hash = keccak(address);
            self.address_hash.set(Some(hash.clone()));
            hash
        })
    }

    /// returns the account's code. If `None` then the code cache isn't available -
    /// get someone who knows to call `note_code`.
    pub fn code(&self) -> Option<Arc<Bytes>> {
        if self.code_hash != KECCAK_EMPTY && self.code_cache.is_empty() {
            return None;
        }
        Some(self.code_cache.clone())
    }

    /// returns the account's code size. If `None` then the code cache or code size cache isn't available -
    /// get someone who knows to call `note_code`.
    pub fn code_size(&self) -> Option<usize> {
        self.code_size.clone()
    }

    #[cfg(test)]
    /// Provide a byte array which hashes to the `code_hash`. returns the hash as a result.
    pub fn note_code(&mut self, code: Bytes) -> Result<(), H256> {
        let h = keccak(&code);
        if self.code_hash == h {
            self.code_cache = Arc::new(code);
            self.code_size = Some(self.code_cache.len());
            Ok(())
        } else {
            Err(h)
        }
    }

    /// Is `code_cache` valid; such that code is going to return Some?
    pub fn is_cached(&self) -> bool {
        !self.code_cache.is_empty()
            || (self.code_cache.is_empty() && self.code_hash == KECCAK_EMPTY)
    }

    /// Provide a database to get `code_hash`. Should not be called if it is a contract without code. Returns the cached code, if successful.
    #[must_use]
    pub fn cache_code(&mut self, db: &HashDB<KeccakHasher, DBValue>) -> Option<Arc<Bytes>> {
        // TODO: fill out self.code_cache;
        trace!(
            "Account::cache_code: ic={}; self.code_hash={:?}, self.code_cache={}",
            self.is_cached(),
            self.code_hash,
            self.code_cache.pretty()
        );

        if self.is_cached() {
            return Some(self.code_cache.clone());
        }

        match db.get(&self.code_hash) {
            Some(x) => {
                self.code_size = Some(x.len());
                self.code_cache = Arc::new(x.into_vec());
                Some(self.code_cache.clone())
            }
            _ => {
                warn!("Failed reverse get of {}", self.code_hash);
                None
            }
        }
    }

    /// Provide code to cache. For correctness, should be the correct code for the account.
    pub fn cache_given_code(&mut self, code: Arc<Bytes>) {
        trace!(
            "Account::cache_given_code: ic={}; self.code_hash={:?}, self.code_cache={}",
            self.is_cached(),
            self.code_hash,
            self.code_cache.pretty()
        );

        self.code_size = Some(code.len());
        self.code_cache = code;
    }

    /// Provide a database to get `code_size`. Should not be called if it is a contract without code. Returns whether
    /// the cache succeeds.
    #[must_use]
    pub fn cache_code_size(&mut self, db: &HashDB<KeccakHasher, DBValue>) -> bool {
        // TODO: fill out self.code_cache;
        trace!(
            "Account::cache_code_size: ic={}; self.code_hash={:?}, self.code_cache={}",
            self.is_cached(),
            self.code_hash,
            self.code_cache.pretty()
        );
        self.code_size.is_some()
            || if self.code_hash != KECCAK_EMPTY {
                match db.get(&self.code_hash) {
                    Some(x) => {
                        self.code_size = Some(x.len());
                        true
                    }
                    _ => {
                        warn!("Failed reverse get of {}", self.code_hash);
                        false
                    }
                }
            } else {
                // If the code hash is empty hash, then the code size is zero.
                self.code_size = Some(0);
                true
            }
    }

    /// Determine whether there are any un-`commit()`-ed storage-setting operations.
    pub fn storage_is_clean(&self) -> bool {
        self.storage_changes.is_empty()
    }

    /// Check if account has zero nonce, balance, no code and no storage.
    ///
    /// NOTE: Will panic if `!self.storage_is_clean()`
    pub fn is_empty(&self) -> bool {
        assert!(
            self.storage_is_clean(),
            "Account::is_empty() may only legally be called when storage is clean."
        );
        self.is_null() && self.storage_root == KECCAK_NULL_RLP
    }

    /// Check if account has zero nonce, balance, no code.
    pub fn is_null(&self) -> bool {
        self.balance.is_zero() && self.nonce.is_zero() && self.code_hash == KECCAK_EMPTY
    }

    /// Check if account is basic (Has no code).
    pub fn is_basic(&self) -> bool {
        self.code_hash == KECCAK_EMPTY
    }

    /// Return the storage root associated with this account or None if it has been altered via the overlay.
    pub fn storage_root(&self) -> Option<H256> {
        if self.storage_is_clean() {
            Some(self.storage_root)
        } else {
            None
        }
    }

    /// Return the original storage root of this account.
    pub fn original_storage_root(&self) -> H256 {
        if let Some((original_storage_root, _)) = self.original_storage_cache {
            original_storage_root
        } else {
            self.storage_root
        }
    }

    /// Whether the base storage root of this account is unchanged.
    pub fn is_base_storage_root_unchanged(&self) -> bool {
        self.original_storage_cache.is_none()
    }

    /// Storage root where the account changes are based upon.
    pub fn base_storage_root(&self) -> H256 {
        self.storage_root
    }

    /// Return the storage overlay.
    pub fn storage_changes(&self) -> &HashMap<H256, H256> {
        &self.storage_changes
    }

    /// Increment the nonce of the account by one.
    pub fn inc_nonce(&mut self) {
        self.nonce = self.nonce.saturating_add(U256::from(1u8));
    }

    /// Increase account balance.
    pub fn add_balance(&mut self, x: &U256) {
        self.balance = self.balance.saturating_add(*x);
    }

    /// Decrease account balance.
    /// Panics if balance is less than `x`
    pub fn sub_balance(&mut self, x: &U256) {
        assert!(self.balance >= *x);
        self.balance = self.balance - *x;
    }

    /// Commit the `storage_changes` to the backing DB and update `storage_root`.
    pub fn commit_storage(
        &mut self,
        trie_factory: &TrieFactory,
        db: &mut HashDB<KeccakHasher, DBValue>,
    ) -> TrieResult<()> {
        let mut t = trie_factory.from_existing(db, &mut self.storage_root)?;
        for (k, v) in self.storage_changes.drain() {
            // cast key and value to trait type,
            // so we can call overloaded `to_bytes` method
            match v.is_zero() {
                true => t.remove(&k)?,
                false => t.insert(&k, &encode(&U256::from(&*v)))?,
            };

            self.storage_cache.borrow_mut().insert(k, v);
        }
        self.original_storage_cache = None;
        Ok(())
    }

    /// Commit any unsaved code. `code_hash` will always return the hash of the `code_cache` after this.
    pub fn commit_code(&mut self, db: &mut HashDB<KeccakHasher, DBValue>) {
        trace!(
            "Commiting code of {:?} - {:?}, {:?}",
            self,
            self.code_filth == Filth::Dirty,
            self.code_cache.is_empty()
        );
        match (self.code_filth == Filth::Dirty, self.code_cache.is_empty()) {
            (true, true) => {
                self.code_size = Some(0);
                self.code_filth = Filth::Clean;
            }
            (true, false) => {
                db.emplace(
                    self.code_hash.clone(),
                    DBValue::from_slice(&*self.code_cache),
                );
                self.code_size = Some(self.code_cache.len());
                self.code_filth = Filth::Clean;
            }
            (false, _) => {}
        }
    }

    /// Export to RLP.
    pub fn rlp(&self) -> Bytes {
        let mut stream = RlpStream::new_list(4);
        stream.append(&self.nonce);
        stream.append(&self.balance);
        stream.append(&self.storage_root);
        stream.append(&self.code_hash);
        stream.out()
    }

    /// Clone basic account data
    pub fn clone_basic(&self) -> Account {
        Account {
            balance: self.balance.clone(),
            nonce: self.nonce.clone(),
            storage_root: self.storage_root.clone(),
            storage_cache: Self::empty_storage_cache(),
            original_storage_cache: self
                .original_storage_cache
                .as_ref()
                .map(|(r, _)| (*r, Self::empty_storage_cache())),
            storage_changes: HashMap::new(),
            code_hash: self.code_hash.clone(),
            code_size: self.code_size.clone(),
            code_cache: self.code_cache.clone(),
            code_filth: self.code_filth,
            address_hash: self.address_hash.clone(),
        }
    }

    /// Clone account data and dirty storage keys
    pub fn clone_dirty(&self) -> Account {
        let mut account = self.clone_basic();
        account.storage_changes = self.storage_changes.clone();
        account
    }

    /// Clone account data, dirty storage keys and cached storage keys.
    pub fn clone_all(&self) -> Account {
        let mut account = self.clone_dirty();
        account.storage_cache = self.storage_cache.clone();
        account.original_storage_cache = self.original_storage_cache.clone();
        account
    }

    /// Replace self with the data from other account merging storage cache.
    /// Basic account data and all modifications are overwritten
    /// with new values.
    pub fn overwrite_with(&mut self, other: Account) {
        self.balance = other.balance;
        self.nonce = other.nonce;
        self.code_hash = other.code_hash;
        self.code_filth = other.code_filth;
        self.code_cache = other.code_cache;
        self.code_size = other.code_size;
        self.address_hash = other.address_hash;
        if self.storage_root == other.storage_root {
            let mut cache = self.storage_cache.borrow_mut();
            for (k, v) in other.storage_cache.into_inner() {
                cache.insert(k, v);
            }
        } else {
            self.storage_cache = other.storage_cache;
        }
        self.original_storage_cache = other.original_storage_cache;
        self.storage_root = other.storage_root;
        self.storage_changes = other.storage_changes;
    }
}

// light client storage proof.
impl Account {
    /// Prove a storage key's existence or nonexistence in the account's storage
    /// trie.
    /// `storage_key` is the hash of the desired storage key, meaning
    /// this will only work correctly under a secure trie.
    pub fn prove_storage(
        &self,
        db: &HashDB<KeccakHasher, DBValue>,
        storage_key: H256,
    ) -> TrieResult<(Vec<Bytes>, H256)> {
        let mut recorder = Recorder::new();

        let trie = TrieDB::new(&db, &self.storage_root)?;
        let item: U256 = {
            let panicky_decoder =
                |bytes: &[u8]| ::rlp::decode(bytes).expect("decoding db value failed");
            let query = (&mut recorder, panicky_decoder);
            trie.get_with(&storage_key, query)?
                .unwrap_or_else(U256::zero)
        };

        Ok((
            recorder.drain().into_iter().map(|r| r.data).collect(),
            item.into(),
        ))
    }
}

impl fmt::Debug for Account {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.debug_struct("Account")
            .field("balance", &self.balance)
            .field("nonce", &self.nonce)
            .field("code", &self.code())
            .field(
                "storage",
                &self.storage_changes.iter().collect::<BTreeMap<_, _>>(),
            )
            .finish()
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use account_db::*;
    use bytes::Bytes;
    use ethereum_types::{Address, H256};
    use journaldb::new_memory_db;
    use rlp_compress::{compress, decompress, snapshot_swapper};

    #[test]
    fn account_compress() {
        let raw = Account::new_basic(2.into(), 4.into()).rlp();
        let compact_vec = compress(&raw, snapshot_swapper());
        assert!(raw.len() > compact_vec.len());
        let again_raw = decompress(&compact_vec, snapshot_swapper());
        assert_eq!(raw, again_raw.into_vec());
    }

    #[test]
    fn storage_at() {
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());
        let rlp = {
            let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
            a.set_storage(0x00u64.into(), 0x1234u64.into());
            a.commit_storage(&Default::default(), &mut db).unwrap();
            a.init_code(vec![]);
            a.commit_code(&mut db);
            a.rlp()
        };

        let a = Account::from_rlp(&rlp).expect("decoding db value failed");
        assert_eq!(
            a.storage_root().unwrap(),
            "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2".into()
        );
        assert_eq!(
            a.storage_at(&db.immutable(), &0x00u64.into()).unwrap(),
            0x1234u64.into()
        );
        assert_eq!(
            a.storage_at(&db.immutable(), &0x01u64.into()).unwrap(),
            H256::default()
        );
    }

    #[test]
    fn note_code() {
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());

        let rlp = {
            let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
            a.init_code(vec![0x55, 0x44, 0xffu8]);
            a.commit_code(&mut db);
            a.rlp()
        };

        let mut a = Account::from_rlp(&rlp).expect("decoding db value failed");
        assert!(a.cache_code(&db.immutable()).is_some());

        let mut a = Account::from_rlp(&rlp).expect("decoding db value failed");
        assert_eq!(a.note_code(vec![0x55, 0x44, 0xffu8]), Ok(()));
    }

    #[test]
    fn commit_storage() {
        let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());
        a.set_storage(0.into(), 0x1234.into());
        assert_eq!(a.storage_root(), None);
        a.commit_storage(&Default::default(), &mut db).unwrap();
        assert_eq!(
            a.storage_root().unwrap(),
            "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2".into()
        );
    }

    #[test]
    fn commit_remove_commit_storage() {
        let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());
        a.set_storage(0.into(), 0x1234.into());
        a.commit_storage(&Default::default(), &mut db).unwrap();
        a.set_storage(1.into(), 0x1234.into());
        a.commit_storage(&Default::default(), &mut db).unwrap();
        a.set_storage(1.into(), 0.into());
        a.commit_storage(&Default::default(), &mut db).unwrap();
        assert_eq!(
            a.storage_root().unwrap(),
            "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2".into()
        );
    }

    #[test]
    fn commit_code() {
        let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());
        a.init_code(vec![0x55, 0x44, 0xffu8]);
        assert_eq!(a.code_filth, Filth::Dirty);
        assert_eq!(a.code_size(), Some(3));
        a.commit_code(&mut db);
        assert_eq!(
            a.code_hash(),
            "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb".into()
        );
    }

    #[test]
    fn reset_code() {
        let mut a = Account::new_contract(69.into(), 0.into(), KECCAK_NULL_RLP);
        let mut db = new_memory_db();
        let mut db = AccountDBMut::new(&mut db, &Address::new());
        a.init_code(vec![0x55, 0x44, 0xffu8]);
        assert_eq!(a.code_filth, Filth::Dirty);
        a.commit_code(&mut db);
        assert_eq!(a.code_filth, Filth::Clean);
        assert_eq!(
            a.code_hash(),
            "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb".into()
        );
        a.reset_code(vec![0x55]);
        assert_eq!(a.code_filth, Filth::Dirty);
        a.commit_code(&mut db);
        assert_eq!(
            a.code_hash(),
            "37bf2238b11b68cdc8382cece82651b59d3c3988873b6e0f33d79694aa45f1be".into()
        );
    }

    #[test]
    fn rlpio() {
        let a = Account::new(69u8.into(), 0u8.into(), HashMap::new(), Bytes::new());
        let b = Account::from_rlp(&a.rlp()).unwrap();
        assert_eq!(a.balance(), b.balance());
        assert_eq!(a.nonce(), b.nonce());
        assert_eq!(a.code_hash(), b.code_hash());
        assert_eq!(a.storage_root(), b.storage_root());
    }

    #[test]
    fn new_account() {
        let a = Account::new(69u8.into(), 0u8.into(), HashMap::new(), Bytes::new());
        assert_eq!(a.rlp().to_hex(), "f8448045a056e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421a0c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470");
        assert_eq!(*a.balance(), 69u8.into());
        assert_eq!(*a.nonce(), 0u8.into());
        assert_eq!(a.code_hash(), KECCAK_EMPTY);
        assert_eq!(a.storage_root().unwrap(), KECCAK_NULL_RLP);
    }
}