use std::sync::Arc;

use jsonrpsee::RpcModule;
use primitives::{
    AccountId, Balance, Block, BlockNumber, Hash, Nonce,
};
use sc_client_api::AuxStore;
use grandpa::FinalityProofProvider;
pub use sc_rpc::{DenyUnsafe, SubscriptionTaskExecutor};
use sp_api::ProvideRuntimeApi;
use block_builder_api::BlockBuilder;
use sp_blockchain::{Error as BlockChainError, HeaderBackend, HeaderMetadata};
use consensus_common::SelectChain;
use babe_primitives::BabeApi;
use sp_keystore::KeystorePtr;
use tx_pool_api::TransactionPool;

/// A type representing all RPC extensions.
pub type RpcExtension = RpcModule<()>;

/// Extra dependencies for BABE.
pub struct BabeDeps {
    /// A handle to the BABE worker for issuing requests.
    pub babe_worker_handle: babe::BabeWorkerHandle<Block>,
    /// The keystore that manages the keys of the node.
    pub keystore: KeystorePtr,
}

/// Extra dependencies for GRANDPA.
pub struct GrandpaDeps<B> {
    /// Voting round info.
    pub shared_voter_state: grandpa::SharedVoterState,
    /// Authority set info.
    pub shared_authority_set: grandpa::SharedAuthoritySet<Hash, BlockNumber>,
    /// Receives notifications about justification events from GRANDPA,
    pub justification_stream: grandpa::GrandpaJustificationStream<Block>,
    /// Subscription manager to keep track of pubsub subscribers.
    pub subscription_executor: sc_rpc::SubscriptionTaskExecutor,
    /// Finality proof provider.
    pub finality_provider: Arc<FinalityProofProvider<B, Block>>,
}

/// Full client dependencies
pub struct FullDeps<C, P, SC, B> {
    /// The client instance to use.
    pub client: Arc<C>,
    /// Transaction pool instance.
    pub pool: Arc<P>,
    /// The [`SelectChain`] Strategy
    pub select_chain: SC,
    /// A copy of the chain spec.
    pub chain_spec: Box<dyn sc_chain_spec::ChainSpec>,
    /// Whether to deny unsafe calls.
    pub deny_unsafe: DenyUnsafe,
    /// BABE specific dependencies
    pub babe: BabeDeps,
    /// GRANDPA specific dependencies
    pub grandpa: GrandpaDeps<B>,
    /// Backend used by the node.
    pub backend: Arc<B>,
}

pub fn create_full_rpc<C, P, SC, B>(
    FullDeps { client, pool, select_chain, chain_spec, deny_unsafe, babe, grandpa, backend } : FullDeps<C, P, SC, B>,
) -> Result<RpcExtension, Box<dyn std::error::Error + Send + Sync>>
where
    C: ProvideRuntimeApi<Block>
        + HeaderBackend<Block>
        + AuxStore
        + HeaderMetadata<Block, Error = BlockChainError>
        + Send
        + Sync
        + 'static,
    C::Api: frame_rpc_system::AccountNonceApi<Block, AccountId, Nonce>,
    C::Api: pallet_transaction_payment_rpc::TransactionPaymentRuntimeApi<Block, Balance>,
    C::Api: BlockBuilder<Block>,
    C::Api: BabeApi<Block>,
    P: TransactionPool + Sync + Send + 'static,
    SC: SelectChain<Block> + 'static,
    B: sc_client_api::Backend<Block> + Send + Sync + 'static,
    B::State: sc_client_api::StateBackend<sp_runtime::traits::HashingFor<Block>>,
{
    use frame_rpc_system::{System, SystemApiServer};
    use pallet_transaction_payment_rpc::{
        TransactionPayment, TransactionPaymentApiServer,
    };
    use babe_rpc::{Babe, BabeApiServer};
    use grandpa_rpc::{Grandpa, GrandpaApiServer};
    use sc_rpc_spec_v2::chain_spec::{ChainSpec, ChainSpecApiServer};
    use sc_sync_state_rpc::{SyncState, SyncStateApiServer};
    use substrate_state_trie_migration_rpc::{
        StateMigration, StateMigrationApiServer,
    };

    let mut io = RpcModule::new(());
    let BabeDeps { babe_worker_handle, keystore } = babe;
    let GrandpaDeps {
        shared_voter_state,
        shared_authority_set,
        justification_stream,
        subscription_executor,
        finality_provider,
    } = grandpa;

    let chain_name = chain_spec.name().to_string();
    let genesis_hash = client.hash(0).ok().flatten().expect("Genesis block exists; qed;");
    let properties = chain_spec.properties();


    io.merge(ChainSpec::new(chain_name, genesis_hash, properties).into_rpc())?;
    io.merge(StateMigration::new(client.clone(), backend.clone(), deny_unsafe).into_rpc())?;
    io.merge(System::new(client.clone(), pool.clone(), deny_unsafe).into_rpc())?;
    io.merge(TransactionPayment::new(client.clone()).into_rpc())?;

    io.merge(
        Babe::new(
            client.clone(),
            babe_worker_handle.clone(),
            keystore,
            select_chain,
            deny_unsafe,
        ).into_rpc()
    )?;

    io.merge(
        Grandpa::new(
            subscription_executor,
            shared_authority_set.clone(),
            shared_voter_state,
            justification_stream,
            finality_provider,
        ).into_rpc(),
    )?;

    io.merge(
        SyncState::new(
            chain_spec,
            client.clone(),
            shared_authority_set,
            babe_worker_handle
        )?.into_rpc(),
    )?;

    Ok(io)
}