use crate::dsn::DsnConfig;
use crate::sync_from_dsn::DsnSyncPieceGetter;
use sc_chain_spec::ChainSpec;
use sc_network::config::{
    MultiaddrWithPeerId, NetworkBackendType, NetworkConfiguration, NodeKeyConfig, SetConfig,
    SyncMode, TransportConfig, DEFAULT_KADEMLIA_REPLICATION_FACTOR,
};
use sc_service::config::{
    IpNetwork, KeystoreConfig, OffchainWorkerConfig, PrometheusConfig, RpcBatchRequestConfig,
};
use sc_service::{
    BasePath, BlocksPruning, Configuration, DatabaseSource, PruningMode, RpcMethods,
    TransactionPoolOptions,
};
use sc_telemetry::TelemetryEndpoints;
use std::collections::HashSet;
use std::fmt;
use std::net::SocketAddr;
use std::num::{NonZeroU32, NonZeroUsize};
use std::ops::Deref;
use std::path::PathBuf;
use std::str::FromStr;
use std::sync::atomic::AtomicBool;
use std::sync::Arc;
use subspace_networking::libp2p::Multiaddr;
use subspace_networking::Node;
use tokio::runtime::Handle;

/// The default max request size in MB, copied from Substrate
pub const RPC_DEFAULT_MAX_REQUEST_SIZE_MB: u32 = 15;
/// The default max response size in MB, copied from Substrate
pub const RPC_DEFAULT_MAX_RESPONSE_SIZE_MB: u32 = 15;

/// Simplified RPC configuration used in Substrate
#[derive(Debug)]
pub struct SubstrateRpcConfiguration {
    /// IP and port (TCP) on which to listen for RPC requests
    pub listen_on: Option<SocketAddr>,
    /// Maximum number of connections for JSON-RPC server
    pub max_connections: u32,
    /// CORS settings for HTTP & WS servers. `None` if all origins are allowed
    pub cors: Option<Vec<String>>,
    /// RPC methods to expose (by default only a safe subset or all of them)
    pub methods: RpcMethods,
    /// RPC rate limiting (calls/minute) for each connection
    pub rate_limit: Option<NonZeroU32>,
    /// Disable RPC rate limiting for certain ip addresses
    pub rate_limit_whitelisted_ips: Vec<IpNetwork>,
    /// Trust proxy headers for rate limiting
    pub rate_limit_trust_proxy_headers: bool,
    /// Maximum allowed subscriptions per rpc connection
    pub max_subscriptions_per_connection: u32,
    /// The number of messages the RPC server is allowed to keep in memory
    pub message_buffer_capacity_per_connection: u32,
    /// Disable RPC batch requests
    pub disable_batch_requests: bool,
    /// Limit the max length per RPC batch request
    pub max_batch_request_len: Option<u32>,
}

/// Simplified network used in Substrate
#[derive(Debug)]
pub struct SubstrateNetworkConfiguration {
    /// Multiaddresses to listen for incoming connections.
    pub listen_on: Vec<sc_network::Multiaddr>,
    /// Multiaddresses to advertise. Detected automatically if empty.
    pub public_addresses: Vec<sc_network::Multiaddr>,
    /// List of initial node addresses
    pub bootstrap_nodes: Vec<MultiaddrWithPeerId>,
    /// The node key configuration, which determines the node's network identity keypair.
    pub node_key: NodeKeyConfig,
    /// Configuration for the default set of nodes used for block syncing and transactions.
    pub default_peers_set: SetConfig,
    /// Name of the node. Sent over the wire for debugging purposes.
    pub node_name: String,
    /// Determines whether we allow keeping non-global (private, shared, loopback..) addresses
    /// in Kademlia DHT.
    pub allow_private_ips: bool,
    /// Sync mode
    pub sync_mode: ChainSyncMode,
    /// Parameter that allows node to forcefully assume it is synced, needed for network
    /// bootstrapping only, as long as two synced nodes remain on the network at any time, this
    /// doesn't need to be used.
    pub force_synced: bool,
}

/// Simplified Substrate configuration that can be converted into [`Configuration`] using
/// [`From`]/[`Into`].
#[derive(Debug)]
pub struct SubstrateConfiguration {
    /// Implementation name
    pub impl_name: String,
    /// Implementation version
    pub impl_version: String,
    /// Farmer node
    pub farmer: bool,
    /// Base path for node data
    pub base_path: PathBuf,
    /// Extrinsic pool configuration
    pub transaction_pool: TransactionPoolOptions,
    /// Network configuration
    pub network: SubstrateNetworkConfiguration,
    /// State pruning settings
    pub state_pruning: PruningMode,
    /// Number of blocks to keep in the db.
    ///
    /// NOTE: only finalized blocks are subject for removal!
    pub blocks_pruning: BlocksPruning,
    /// RPC configuration
    pub rpc_options: SubstrateRpcConfiguration,
    /// IP and port (TCP) to start Prometheus exporter on
    pub prometheus_listen_on: Option<SocketAddr>,
    /// Telemetry service URL. `None` if disabled.
    pub telemetry_endpoints: Option<TelemetryEndpoints>,
    /// Enable authoring even when offline
    pub force_authoring: bool,
    /// Chain specification
    pub chain_spec: Box<dyn ChainSpec>,
    /// Configuration of the output format that the informant uses.
    pub informant_output_format: sc_informant::OutputFormat,
}

impl From<SubstrateConfiguration> for Configuration {
    fn from(configuration: SubstrateConfiguration) -> Self {
        let net_config_path = configuration.base_path.join("network");
        let default_peers_set_num_full = configuration.network.default_peers_set.in_peers
            + configuration.network.default_peers_set.out_peers;
        let client_version = format!("{}/{}", configuration.impl_name, configuration.impl_version);

        Self {
            impl_name: configuration.impl_name,
            impl_version: configuration.impl_version,
            tokio_handle: Handle::current(),
            transaction_pool: configuration.transaction_pool,
            network: NetworkConfiguration {
                net_config_path: Some(net_config_path.clone()),
                listen_addresses: configuration.network.listen_on,
                public_addresses: configuration.network.public_addresses,
                boot_nodes: if !configuration.network.bootstrap_nodes.is_empty() {
                    configuration.network.bootstrap_nodes
                } else {
                    configuration.chain_spec.boot_nodes().to_vec()
                },
                node_key: configuration.network.node_key,
                default_peers_set: configuration.network.default_peers_set,
                default_peers_set_num_full,
                client_version,
                node_name: configuration.network.node_name,
                transport: TransportConfig::Normal {
                    enable_mdns: false,
                    allow_private_ip: configuration.network.allow_private_ips,
                },
                // Substrate's default
                max_parallel_downloads: 5,
                // Substrate's default
                max_blocks_per_request: 64,
                sync_mode: SyncMode::Full,
                pause_sync: Arc::new(AtomicBool::new(false)),
                // Substrate's default
                enable_dht_random_walk: true,
                // Substrate's default
                allow_non_globals_in_dht: configuration.network.allow_private_ips,
                // Substrate's default
                kademlia_disjoint_query_paths: false,
                kademlia_replication_factor: NonZeroUsize::new(DEFAULT_KADEMLIA_REPLICATION_FACTOR)
                    .expect("value is a constant; constant is non-zero; qed"),
                ipfs_server: false,
                yamux_window_size: None,
                network_backend: NetworkBackendType::Libp2p,
                force_synced: configuration.network.force_synced,
            },
            // Not used on consensus chain
            keystore: KeystoreConfig::InMemory,
            database: DatabaseSource::ParityDb {
                path: configuration.base_path.join("db"),
            },
            data_path: configuration.base_path.clone(),
            // Substrate's default
            trie_cache_maximum_size: Some(64 * 1024 * 1024),
            state_pruning: Some(configuration.state_pruning),
            blocks_pruning: configuration.blocks_pruning,
            wasm_method: Default::default(),
            wasm_runtime_overrides: None,
            rpc_addr: configuration.rpc_options.listen_on,
            rpc_methods: configuration.rpc_options.methods,
            rpc_max_connections: configuration.rpc_options.max_connections,
            rpc_cors: configuration.rpc_options.cors,
            rpc_max_request_size: RPC_DEFAULT_MAX_REQUEST_SIZE_MB,
            rpc_max_response_size: RPC_DEFAULT_MAX_RESPONSE_SIZE_MB,
            rpc_id_provider: None,
            rpc_max_subs_per_conn: configuration.rpc_options.max_subscriptions_per_connection,
            // Doesn't matter since we have specified address above
            rpc_port: 0,
            rpc_message_buffer_capacity: configuration
                .rpc_options
                .message_buffer_capacity_per_connection,
            rpc_batch_config: if configuration.rpc_options.disable_batch_requests {
                RpcBatchRequestConfig::Disabled
            } else if let Some(l) = configuration.rpc_options.max_batch_request_len {
                RpcBatchRequestConfig::Limit(l)
            } else {
                RpcBatchRequestConfig::Unlimited
            },
            rpc_rate_limit: configuration.rpc_options.rate_limit,
            rpc_rate_limit_whitelisted_ips: configuration.rpc_options.rate_limit_whitelisted_ips,
            rpc_rate_limit_trust_proxy_headers: configuration
                .rpc_options
                .rate_limit_trust_proxy_headers,
            prometheus_config: configuration
                .prometheus_listen_on
                .map(|prometheus_listen_on| {
                    PrometheusConfig::new_with_default_registry(
                        prometheus_listen_on,
                        configuration.chain_spec.id().to_string(),
                    )
                }),
            telemetry_endpoints: configuration.telemetry_endpoints,
            default_heap_pages: None,
            // Offchain worker is not used
            // indexing is used to store the mmr leaves from Runtime
            offchain_worker: OffchainWorkerConfig {
                enabled: false,
                indexing_enabled: true,
            },
            force_authoring: configuration.force_authoring,
            disable_grandpa: true,
            dev_key_seed: None,
            tracing_targets: None,
            tracing_receiver: Default::default(),
            chain_spec: configuration.chain_spec,
            // Substrate's default
            max_runtime_instances: 8,
            // Substrate's default
            announce_block: true,
            role: if configuration.farmer {
                sc_service::Role::Authority
            } else {
                sc_service::Role::Full
            },
            base_path: BasePath::new(configuration.base_path),
            informant_output_format: configuration.informant_output_format,
            // Substrate's default
            runtime_cache_size: 2,
        }
    }
}

/// Subspace networking instantiation variant
#[derive(Debug)]
#[allow(clippy::large_enum_variant)]
pub enum SubspaceNetworking {
    /// Use existing networking instance
    Reuse {
        /// Node instance
        node: Node,
        /// Bootstrap nodes used (that can be also sent to the farmer over RPC)
        bootstrap_nodes: Vec<Multiaddr>,
    },
    /// Networking must be instantiated internally
    Create {
        /// Configuration to use for DSN instantiation
        config: DsnConfig,
    },
}

/// Subspace-specific service configuration.
#[derive(Debug)]
pub struct SubspaceConfiguration {
    /// Base configuration.
    pub base: Configuration,
    /// Whether slot notifications need to be present even if node is not responsible for block
    /// authoring.
    pub force_new_slot_notifications: bool,
    /// Subspace networking (DSN).
    pub subspace_networking: SubspaceNetworking,
    /// DSN piece getter
    pub dsn_piece_getter: Option<Arc<dyn DsnSyncPieceGetter + Send + Sync + 'static>>,
    /// Is this node a Timekeeper
    pub is_timekeeper: bool,
    /// CPU cores that timekeeper can use
    pub timekeeper_cpu_cores: HashSet<usize>,
    /// Defines blockchain sync mode
    pub sync: ChainSyncMode,
}

/// Syncing mode.
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum ChainSyncMode {
    /// Full sync. Download and verify all blocks from DSN.
    Full,
    /// Download latest state and related blocks only. Run full DSN-sync afterwards.
    Snap,
}

impl FromStr for ChainSyncMode {
    type Err = String;

    fn from_str(input: &str) -> Result<Self, Self::Err> {
        match input {
            "full" => Ok(Self::Full),
            "snap" => Ok(Self::Snap),
            _ => Err("Unsupported sync type: use full or snap".to_string()),
        }
    }
}

impl fmt::Display for ChainSyncMode {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Full => f.write_str("full"),
            Self::Snap => f.write_str("snap"),
        }
    }
}

impl Default for ChainSyncMode {
    fn default() -> Self {
        Self::Full
    }
}

impl Deref for SubspaceConfiguration {
    type Target = Configuration;

    fn deref(&self) -> &Self::Target {
        &self.base
    }
}