//! Service and ServiceFactory implementation. Specialized wrapper over substrate service.

use sc_client_api::{ExecutorProvider, RemoteBackend};
use sc_executor::native_executor_instance;
pub use sc_executor::NativeExecutor;
use sc_finality_grandpa::SharedVoterState;
use sc_keystore::LocalKeystore;
use sc_service::{error::Error as ServiceError, Configuration, TaskManager};
use sp_consensus_aura::sr25519::AuthorityPair as AuraPair;
use sp_inherents::InherentDataProviders;
use std::{sync::Arc, time::Duration};

use anagolay_runtime::{self, opaque::Block, RuntimeApi};

// Our native executor instance.
native_executor_instance!(
    pub Executor,
    anagolay_runtime::api::dispatch,
    anagolay_runtime::native_version,
    frame_benchmarking::benchmarking::HostFunctions,
);

type FullClient = sc_service::TFullClient<Block, RuntimeApi, Executor>;
type FullBackend = sc_service::TFullBackend<Block>;
type FullSelectChain = sc_consensus::LongestChain<FullBackend, Block>;

pub fn new_partial(
  config: &Configuration,
) -> Result<
  sc_service::PartialComponents<
    FullClient,
    FullBackend,
    FullSelectChain,
    sp_consensus::DefaultImportQueue<Block, FullClient>,
    sc_transaction_pool::FullPool<Block, FullClient>,
    (
      sc_consensus_aura::AuraBlockImport<
        Block,
        FullClient,
        sc_finality_grandpa::GrandpaBlockImport<FullBackend, Block, FullClient, FullSelectChain>,
        AuraPair,
      >,
      sc_finality_grandpa::LinkHalf<Block, FullClient, FullSelectChain>,
    ),
  >,
  ServiceError,
> {
  if config.keystore_remote.is_some() {
    return Err(ServiceError::Other(format!("Remote Keystores are not supported.")));
  }
  let inherent_data_providers = InherentDataProviders::new();

  let (client, backend, keystore_container, task_manager) =
    sc_service::new_full_parts::<Block, RuntimeApi, Executor>(&config)?;
  let client = Arc::new(client);

  let select_chain = sc_consensus::LongestChain::new(backend.clone());

  let transaction_pool = sc_transaction_pool::BasicPool::new_full(
    config.transaction_pool.clone(),
    config.role.is_authority().into(),
    config.prometheus_registry(),
    task_manager.spawn_handle(),
    client.clone(),
  );

  let (grandpa_block_import, grandpa_link) =
    sc_finality_grandpa::block_import(client.clone(), &(client.clone() as Arc<_>), select_chain.clone())?;

  let aura_block_import =
    sc_consensus_aura::AuraBlockImport::<_, _, _, AuraPair>::new(grandpa_block_import.clone(), client.clone());

  let import_queue = sc_consensus_aura::import_queue::<_, _, _, AuraPair, _, _>(
    sc_consensus_aura::slot_duration(&*client)?,
    aura_block_import.clone(),
    Some(Box::new(grandpa_block_import.clone())),
    client.clone(),
    inherent_data_providers.clone(),
    &task_manager.spawn_handle(),
    config.prometheus_registry(),
    sp_consensus::CanAuthorWithNativeVersion::new(client.executor().clone()),
  )?;

  Ok(sc_service::PartialComponents {
    client,
    backend,
    task_manager,
    import_queue,
    keystore_container,
    select_chain,
    transaction_pool,
    inherent_data_providers,
    other: (aura_block_import, grandpa_link),
  })
}

fn remote_keystore(_url: &String) -> Result<Arc<LocalKeystore>, &'static str> {
  // FIXME: here would the concrete keystore be built,
  //        must return a concrete type (NOT `LocalKeystore`) that
  //        implements `CryptoStore` and `SyncCryptoStore`
  Err("Remote Keystore not supported.")
}

/// Builds a new service for a full client.
pub fn new_full(mut config: Configuration) -> Result<TaskManager, ServiceError> {
  let sc_service::PartialComponents {
    client,
    backend,
    mut task_manager,
    import_queue,
    mut keystore_container,
    select_chain,
    transaction_pool,
    inherent_data_providers,
    other: (block_import, grandpa_link),
  } = new_partial(&config)?;

  if let Some(url) = &config.keystore_remote {
    match remote_keystore(url) {
      Ok(k) => keystore_container.set_remote_keystore(k),
      Err(e) => {
        return Err(ServiceError::Other(format!(
          "Error hooking up remote keystore for {}: {}",
          url, e
        )))
      }
    };
  }

  config
    .network
    .extra_sets
    .push(sc_finality_grandpa::grandpa_peers_set_config());

  let (network, network_status_sinks, system_rpc_tx, network_starter) =
    sc_service::build_network(sc_service::BuildNetworkParams {
      config: &config,
      client: client.clone(),
      transaction_pool: transaction_pool.clone(),
      spawn_handle: task_manager.spawn_handle(),
      import_queue,
      on_demand: None,
      block_announce_validator_builder: None,
    })?;

  if config.offchain_worker.enabled {
    sc_service::build_offchain_workers(
      &config,
      backend.clone(),
      task_manager.spawn_handle(),
      client.clone(),
      network.clone(),
    );
  }

  let role = config.role.clone();
  let force_authoring = config.force_authoring;
  let backoff_authoring_blocks: Option<()> = None;
  let name = config.network.node_name.clone();
  let enable_grandpa = !config.disable_grandpa;
  let prometheus_registry = config.prometheus_registry().cloned();

  let rpc_extensions_builder = {
    let client = client.clone();
    let pool = transaction_pool.clone();

    Box::new(move |deny_unsafe, _| {
      let deps = crate::rpc::FullDeps {
        client: client.clone(),
        pool: pool.clone(),
        deny_unsafe,
      };

      crate::rpc::create_full(deps)
    })
  };

  let (_rpc_handlers, telemetry_connection_notifier) = sc_service::spawn_tasks(sc_service::SpawnTasksParams {
    network: network.clone(),
    client: client.clone(),
    keystore: keystore_container.sync_keystore(),
    task_manager: &mut task_manager,
    transaction_pool: transaction_pool.clone(),
    rpc_extensions_builder,
    on_demand: None,
    remote_blockchain: None,
    backend,
    network_status_sinks,
    system_rpc_tx,
    config,
  })?;

  if role.is_authority() {
    let proposer_factory = sc_basic_authorship::ProposerFactory::new(
      task_manager.spawn_handle(),
      client.clone(),
      transaction_pool,
      prometheus_registry.as_ref(),
    );

    let can_author_with = sp_consensus::CanAuthorWithNativeVersion::new(client.executor().clone());

    let aura = sc_consensus_aura::start_aura::<_, _, _, _, _, AuraPair, _, _, _, _>(
      sc_consensus_aura::slot_duration(&*client)?,
      client.clone(),
      select_chain,
      block_import,
      proposer_factory,
      network.clone(),
      inherent_data_providers.clone(),
      force_authoring,
      backoff_authoring_blocks,
      keystore_container.sync_keystore(),
      can_author_with,
    )?;

    // the AURA authoring task is considered essential, i.e. if it
    // fails we take down the service with it.
    task_manager.spawn_essential_handle().spawn_blocking("aura", aura);
  }

  // if the node isn't actively participating in consensus then it doesn't
  // need a keystore, regardless of which protocol we use below.
  let keystore = if role.is_authority() {
    Some(keystore_container.sync_keystore())
  } else {
    None
  };

  let grandpa_config = sc_finality_grandpa::Config {
    // FIXME #1578 make this available through chainspec
    gossip_duration: Duration::from_millis(333),
    justification_period: 512,
    name: Some(name),
    observer_enabled: false,
    keystore,
    is_authority: role.is_network_authority(),
  };

  if enable_grandpa {
    // start the full GRANDPA voter
    // NOTE: non-authorities could run the GRANDPA observer protocol, but at
    // this point the full voter should provide better guarantees of block
    // and vote data availability than the observer. The observer has not
    // been tested extensively yet and having most nodes in a network run it
    // could lead to finality stalls.
    let grandpa_config = sc_finality_grandpa::GrandpaParams {
      config: grandpa_config,
      link: grandpa_link,
      network,
      voting_rule: sc_finality_grandpa::VotingRulesBuilder::default().build(),
      prometheus_registry,
      shared_voter_state: SharedVoterState::empty(),
      telemetry_on_connect: telemetry_connection_notifier.map(|x| x.on_connect_stream()),
    };

    // the GRANDPA voter task is considered infallible, i.e.
    // if it fails we take down the service with it.
    task_manager
      .spawn_essential_handle()
      .spawn_blocking("grandpa-voter", sc_finality_grandpa::run_grandpa_voter(grandpa_config)?);
  }

  network_starter.start_network();
  Ok(task_manager)
}

/// Builds a new service for a light client.
pub fn new_light(mut config: Configuration) -> Result<TaskManager, ServiceError> {
  let (client, backend, keystore_container, mut task_manager, on_demand) =
    sc_service::new_light_parts::<Block, RuntimeApi, Executor>(&config)?;

  config
    .network
    .extra_sets
    .push(sc_finality_grandpa::grandpa_peers_set_config());

  let select_chain = sc_consensus::LongestChain::new(backend.clone());

  let transaction_pool = Arc::new(sc_transaction_pool::BasicPool::new_light(
    config.transaction_pool.clone(),
    config.prometheus_registry(),
    task_manager.spawn_handle(),
    client.clone(),
    on_demand.clone(),
  ));

  let (grandpa_block_import, _) =
    sc_finality_grandpa::block_import(client.clone(), &(client.clone() as Arc<_>), select_chain.clone())?;

  let aura_block_import =
    sc_consensus_aura::AuraBlockImport::<_, _, _, AuraPair>::new(grandpa_block_import.clone(), client.clone());

  let import_queue = sc_consensus_aura::import_queue::<_, _, _, AuraPair, _, _>(
    sc_consensus_aura::slot_duration(&*client)?,
    aura_block_import,
    Some(Box::new(grandpa_block_import)),
    client.clone(),
    InherentDataProviders::new(),
    &task_manager.spawn_handle(),
    config.prometheus_registry(),
    sp_consensus::NeverCanAuthor,
  )?;

  let (network, network_status_sinks, system_rpc_tx, network_starter) =
    sc_service::build_network(sc_service::BuildNetworkParams {
      config: &config,
      client: client.clone(),
      transaction_pool: transaction_pool.clone(),
      spawn_handle: task_manager.spawn_handle(),
      import_queue,
      on_demand: Some(on_demand.clone()),
      block_announce_validator_builder: None,
    })?;

  if config.offchain_worker.enabled {
    sc_service::build_offchain_workers(
      &config,
      backend.clone(),
      task_manager.spawn_handle(),
      client.clone(),
      network.clone(),
    );
  }

  sc_service::spawn_tasks(sc_service::SpawnTasksParams {
    remote_blockchain: Some(backend.remote_blockchain()),
    transaction_pool,
    task_manager: &mut task_manager,
    on_demand: Some(on_demand),
    rpc_extensions_builder: Box::new(|_, _| ()),
    config,
    client,
    keystore: keystore_container.sync_keystore(),
    backend,
    network,
    network_status_sinks,
    system_rpc_tx,
  })?;

  network_starter.start_network();

  Ok(task_manager)
}