use {
    super::{
        storage::SerializableAccountStorageEntry,
        utils::{serialize_iter_as_map, serialize_iter_as_seq},
        *,
    },
    crate::{ancestors::AncestorsForSerialization, stakes::StakesCache},
    solana_measure::measure::Measure,
    std::{cell::RefCell, collections::HashSet, sync::RwLock},
};

type AccountsDbFields = super::AccountsDbFields<SerializableAccountStorageEntry>;

#[derive(Default, Clone, PartialEq, Debug, Deserialize, Serialize, AbiExample)]
struct UnusedAccounts {
    unused1: HashSet<Pubkey>,
    unused2: HashSet<Pubkey>,
    unused3: HashMap<Pubkey, u64>,
}

// Deserializable version of Bank which need not be serializable,
// because it's handled by SerializableVersionedBank.
// So, sync fields with it!
#[derive(Clone, Deserialize)]
struct DeserializableVersionedBank {
    blockhash_queue: BlockhashQueue,
    ancestors: AncestorsForSerialization,
    hash: Hash,
    parent_hash: Hash,
    parent_slot: Slot,
    hard_forks: HardForks,
    transaction_count: u64,
    tick_height: u64,
    signature_count: u64,
    capitalization: u64,
    max_tick_height: u64,
    hashes_per_tick: Option<u64>,
    ticks_per_slot: u64,
    ns_per_slot: u128,
    genesis_creation_time: UnixTimestamp,
    slots_per_year: f64,
    accounts_data_len: u64,
    slot: Slot,
    epoch: Epoch,
    block_height: u64,
    collector_id: Pubkey,
    collector_fees: u64,
    fee_calculator: FeeCalculator,
    fee_rate_governor: FeeRateGovernor,
    collected_rent: u64,
    rent_collector: RentCollector,
    epoch_schedule: EpochSchedule,
    inflation: Inflation,
    stakes: Stakes,
    #[allow(dead_code)]
    unused_accounts: UnusedAccounts,
    epoch_stakes: HashMap<Epoch, EpochStakes>,
    is_delta: bool,
}

impl From<DeserializableVersionedBank> for BankFieldsToDeserialize {
    fn from(dvb: DeserializableVersionedBank) -> Self {
        BankFieldsToDeserialize {
            blockhash_queue: dvb.blockhash_queue,
            ancestors: dvb.ancestors,
            hash: dvb.hash,
            parent_hash: dvb.parent_hash,
            parent_slot: dvb.parent_slot,
            hard_forks: dvb.hard_forks,
            transaction_count: dvb.transaction_count,
            tick_height: dvb.tick_height,
            signature_count: dvb.signature_count,
            capitalization: dvb.capitalization,
            max_tick_height: dvb.max_tick_height,
            hashes_per_tick: dvb.hashes_per_tick,
            ticks_per_slot: dvb.ticks_per_slot,
            ns_per_slot: dvb.ns_per_slot,
            genesis_creation_time: dvb.genesis_creation_time,
            slots_per_year: dvb.slots_per_year,
            accounts_data_len: dvb.accounts_data_len,
            slot: dvb.slot,
            epoch: dvb.epoch,
            block_height: dvb.block_height,
            collector_id: dvb.collector_id,
            collector_fees: dvb.collector_fees,
            fee_calculator: dvb.fee_calculator,
            fee_rate_governor: dvb.fee_rate_governor,
            collected_rent: dvb.collected_rent,
            rent_collector: dvb.rent_collector,
            epoch_schedule: dvb.epoch_schedule,
            inflation: dvb.inflation,
            stakes: dvb.stakes,
            epoch_stakes: dvb.epoch_stakes,
            is_delta: dvb.is_delta,
        }
    }
}

// Serializable version of Bank, not Deserializable to avoid cloning by using refs.
// Sync fields with DeserializableVersionedBank!
#[derive(Serialize)]
struct SerializableVersionedBank<'a> {
    blockhash_queue: &'a RwLock<BlockhashQueue>,
    ancestors: &'a AncestorsForSerialization,
    hash: Hash,
    parent_hash: Hash,
    parent_slot: Slot,
    hard_forks: &'a RwLock<HardForks>,
    transaction_count: u64,
    tick_height: u64,
    signature_count: u64,
    capitalization: u64,
    max_tick_height: u64,
    hashes_per_tick: Option<u64>,
    ticks_per_slot: u64,
    ns_per_slot: u128,
    genesis_creation_time: UnixTimestamp,
    slots_per_year: f64,
    accounts_data_len: u64,
    slot: Slot,
    epoch: Epoch,
    block_height: u64,
    collector_id: Pubkey,
    collector_fees: u64,
    fee_calculator: FeeCalculator,
    fee_rate_governor: FeeRateGovernor,
    collected_rent: u64,
    rent_collector: RentCollector,
    epoch_schedule: EpochSchedule,
    inflation: Inflation,
    stakes: &'a StakesCache,
    unused_accounts: UnusedAccounts,
    epoch_stakes: &'a HashMap<Epoch, EpochStakes>,
    is_delta: bool,
}

impl<'a> From<crate::bank::BankFieldsToSerialize<'a>> for SerializableVersionedBank<'a> {
    fn from(rhs: crate::bank::BankFieldsToSerialize<'a>) -> Self {
        Self {
            blockhash_queue: rhs.blockhash_queue,
            ancestors: rhs.ancestors,
            hash: rhs.hash,
            parent_hash: rhs.parent_hash,
            parent_slot: rhs.parent_slot,
            hard_forks: rhs.hard_forks,
            transaction_count: rhs.transaction_count,
            tick_height: rhs.tick_height,
            signature_count: rhs.signature_count,
            capitalization: rhs.capitalization,
            max_tick_height: rhs.max_tick_height,
            hashes_per_tick: rhs.hashes_per_tick,
            ticks_per_slot: rhs.ticks_per_slot,
            ns_per_slot: rhs.ns_per_slot,
            genesis_creation_time: rhs.genesis_creation_time,
            slots_per_year: rhs.slots_per_year,
            accounts_data_len: rhs.accounts_data_len,
            slot: rhs.slot,
            epoch: rhs.epoch,
            block_height: rhs.block_height,
            collector_id: rhs.collector_id,
            collector_fees: rhs.collector_fees,
            fee_calculator: rhs.fee_calculator,
            fee_rate_governor: rhs.fee_rate_governor,
            collected_rent: rhs.collected_rent,
            rent_collector: rhs.rent_collector,
            epoch_schedule: rhs.epoch_schedule,
            inflation: rhs.inflation,
            stakes: rhs.stakes,
            unused_accounts: UnusedAccounts::default(),
            epoch_stakes: rhs.epoch_stakes,
            is_delta: rhs.is_delta,
        }
    }
}

#[cfg(RUSTC_WITH_SPECIALIZATION)]
impl<'a> solana_frozen_abi::abi_example::IgnoreAsHelper for SerializableVersionedBank<'a> {}

pub(super) struct Context {}

impl<'a> TypeContext<'a> for Context {
    type SerializableAccountStorageEntry = SerializableAccountStorageEntry;

    fn serialize_bank_and_storage<S: serde::ser::Serializer>(
        serializer: S,
        serializable_bank: &SerializableBankAndStorage<'a, Self>,
    ) -> std::result::Result<S::Ok, S::Error>
    where
        Self: std::marker::Sized,
    {
        let ancestors = HashMap::from(&serializable_bank.bank.ancestors);
        let fields = serializable_bank.bank.get_fields_to_serialize(&ancestors);
        (
            SerializableVersionedBank::from(fields),
            SerializableAccountsDb::<'a, Self> {
                accounts_db: &*serializable_bank.bank.rc.accounts.accounts_db,
                slot: serializable_bank.bank.rc.slot,
                account_storage_entries: serializable_bank.snapshot_storages,
                phantom: std::marker::PhantomData::default(),
            },
        )
            .serialize(serializer)
    }

    fn serialize_accounts_db_fields<S: serde::ser::Serializer>(
        serializer: S,
        serializable_db: &SerializableAccountsDb<'a, Self>,
    ) -> std::result::Result<S::Ok, S::Error>
    where
        Self: std::marker::Sized,
    {
        // sample write version before serializing storage entries
        let version = serializable_db
            .accounts_db
            .write_version
            .load(Ordering::Acquire);

        // (1st of 3 elements) write the list of account storage entry lists out as a map
        let entry_count = RefCell::<usize>::new(0);
        let entries =
            serialize_iter_as_map(serializable_db.account_storage_entries.iter().map(|x| {
                *entry_count.borrow_mut() += x.len();
                (
                    x.first().unwrap().slot(),
                    serialize_iter_as_seq(
                        x.iter()
                            .map(|x| Self::SerializableAccountStorageEntry::from(x.as_ref())),
                    ),
                )
            }));
        let slot = serializable_db.slot;
        let hash = serializable_db
            .accounts_db
            .bank_hashes
            .read()
            .unwrap()
            .get(&serializable_db.slot)
            .unwrap_or_else(|| panic!("No bank_hashes entry for slot {}", serializable_db.slot))
            .clone();

        // for now, prior_roots is the same as 'roots' and is redundant with the storages we persist in the snapshot
        let prior_roots = serializable_db
            .accounts_db
            .accounts_index
            .roots_tracker
            .read()
            .unwrap()
            .roots
            .get_all();
        let prior_roots_with_hash = Vec::<(Slot, Hash)>::default();

        let mut serialize_account_storage_timer = Measure::start("serialize_account_storage_ms");
        let result = (
            entries,
            version,
            slot,
            hash,
            prior_roots,
            prior_roots_with_hash,
        )
            .serialize(serializer);
        serialize_account_storage_timer.stop();
        datapoint_info!(
            "serialize_account_storage_ms",
            ("duration", serialize_account_storage_timer.as_ms(), i64),
            ("num_entries", *entry_count.borrow(), i64),
        );
        result
    }

    fn deserialize_bank_fields<R>(
        mut stream: &mut BufReader<R>,
    ) -> Result<(BankFieldsToDeserialize, AccountsDbFields), Error>
    where
        R: Read,
    {
        let bank_fields = deserialize_from::<_, DeserializableVersionedBank>(&mut stream)?.into();
        let accounts_db_fields = Self::deserialize_accounts_db_fields(stream)?;
        Ok((bank_fields, accounts_db_fields))
    }

    fn deserialize_accounts_db_fields<R>(
        stream: &mut BufReader<R>,
    ) -> Result<AccountsDbFields, Error>
    where
        R: Read,
    {
        deserialize_from(stream)
    }
}
