// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.

// Parity 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 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.  If not, see <http://www.gnu.org/licenses/>.

extern crate ansi_term;
use self::ansi_term::Colour::{White, Yellow, Green, Cyan, Blue};
use self::ansi_term::Style;

use std::sync::{Arc};
use std::sync::atomic::{AtomicUsize, AtomicBool, Ordering as AtomicOrdering};
use std::time::{Instant, Duration};
use io::{TimerToken, IoContext, IoHandler};
use isatty::{stdout_isatty};
use ethsync::{SyncProvider, ManageNetwork};
use util::{RwLock, Mutex, H256, Colour, Bytes};
use ethcore::client::*;
use ethcore::service::ClientIoMessage;
use ethcore::snapshot::service::Service as SnapshotService;
use ethcore::snapshot::{RestorationStatus, SnapshotService as SS};
use number_prefix::{binary_prefix, Standalone, Prefixed};
use parity_rpc::{is_major_importing};
use parity_rpc::informant::RpcStats;

pub struct Informant {
	report: RwLock<Option<ClientReport>>,
	last_tick: RwLock<Instant>,
	with_color: bool,
	client: Arc<Client>,
	snapshot: Option<Arc<SnapshotService>>,
	sync: Option<Arc<SyncProvider>>,
	net: Option<Arc<ManageNetwork>>,
	rpc_stats: Option<Arc<RpcStats>>,
	last_import: Mutex<Instant>,
	skipped: AtomicUsize,
	skipped_txs: AtomicUsize,
	in_shutdown: AtomicBool,
}

/// Format byte counts to standard denominations.
pub fn format_bytes(b: usize) -> String {
	match binary_prefix(b as f64) {
		Standalone(bytes)   => format!("{} bytes", bytes),
		Prefixed(prefix, n) => format!("{:.0} {}B", n, prefix),
	}
}

/// Something that can be converted to milliseconds.
pub trait MillisecondDuration {
	/// Get the value in milliseconds.
	fn as_milliseconds(&self) -> u64;
}

impl MillisecondDuration for Duration {
	fn as_milliseconds(&self) -> u64 {
		self.as_secs() * 1000 + self.subsec_nanos() as u64 / 1_000_000
	}
}

impl Informant {
	/// Make a new instance potentially `with_color` output.
	pub fn new(
		client: Arc<Client>,
		sync: Option<Arc<SyncProvider>>,
		net: Option<Arc<ManageNetwork>>,
		snapshot: Option<Arc<SnapshotService>>,
		rpc_stats: Option<Arc<RpcStats>>,
		with_color: bool,
	) -> Self {
		Informant {
			report: RwLock::new(None),
			last_tick: RwLock::new(Instant::now()),
			with_color: with_color,
			client: client,
			snapshot: snapshot,
			sync: sync,
			net: net,
			rpc_stats: rpc_stats,
			last_import: Mutex::new(Instant::now()),
			skipped: AtomicUsize::new(0),
			skipped_txs: AtomicUsize::new(0),
			in_shutdown: AtomicBool::new(false),
		}
	}

	/// Signal that we're shutting down; no more output necessary.
	pub fn shutdown(&self) {
		self.in_shutdown.store(true, ::std::sync::atomic::Ordering::SeqCst);
	}

	#[cfg_attr(feature="dev", allow(match_bool))]
	pub fn tick(&self) {
		let elapsed = self.last_tick.read().elapsed();
		if elapsed < Duration::from_secs(5) {
			return;
		}

		let chain_info = self.client.chain_info();
		let queue_info = self.client.queue_info();
		let cache_info = self.client.blockchain_cache_info();
		let network_config = self.net.as_ref().map(|n| n.network_config());
		let sync_status = self.sync.as_ref().map(|s| s.status());
		let rpc_stats = self.rpc_stats.as_ref();

		let importing = is_major_importing(sync_status.map(|s| s.state), self.client.queue_info());
		let (snapshot_sync, snapshot_current, snapshot_total) = self.snapshot.as_ref().map_or((false, 0, 0), |s|
			match s.status() {
				RestorationStatus::Ongoing { state_chunks, block_chunks, state_chunks_done, block_chunks_done } =>
					(true, state_chunks_done + block_chunks_done, state_chunks + block_chunks),
				_ => (false, 0, 0),
			}
		);

		if !importing && !snapshot_sync && elapsed < Duration::from_secs(30) {
			return;
		}

		*self.last_tick.write() = Instant::now();

		let mut write_report = self.report.write();
		let report = self.client.report();

		let paint = |c: Style, t: String| match self.with_color && stdout_isatty() {
			true => format!("{}", c.paint(t)),
			false => t,
		};

		info!(target: "import", "{}  {}  {}  {}",
			match importing {
				true => match snapshot_sync {
					false => format!("Syncing {} {}  {}  {}+{} Qed",
						paint(White.bold(), format!("{:>8}", format!("#{}", chain_info.best_block_number))),
						paint(White.bold(), format!("{}", chain_info.best_block_hash)),
						{
							let last_report = match *write_report { Some(ref last_report) => last_report.clone(), _ => ClientReport::default() };
							format!("{} blk/s {} tx/s {} Mgas/s",
									paint(Yellow.bold(), format!("{:4}", ((report.blocks_imported - last_report.blocks_imported) * 1000) as u64 / elapsed.as_milliseconds())),
									paint(Yellow.bold(), format!("{:4}", ((report.transactions_applied - last_report.transactions_applied) * 1000) as u64 / elapsed.as_milliseconds())),
									paint(Yellow.bold(), format!("{:3}", ((report.gas_processed - last_report.gas_processed) / From::from(elapsed.as_milliseconds() * 1000)).low_u64()))
								   )
						},
						paint(Green.bold(), format!("{:5}", queue_info.unverified_queue_size)),
						paint(Green.bold(), format!("{:5}", queue_info.verified_queue_size))
					),
					true => format!("Syncing snapshot {}/{}", snapshot_current, snapshot_total),
				},
				false => String::new(),
			},
			match (&sync_status, &network_config) {
				(&Some(ref sync_info), &Some(ref net_config)) => format!("{}{}/{}/{} peers",
					match importing {
						true => format!("{}   ", paint(Green.bold(), format!("{:>8}", format!("#{}", sync_info.last_imported_block_number.unwrap_or(chain_info.best_block_number))))),
						false => match sync_info.last_imported_old_block_number {
							Some(number) => format!("{}   ", paint(Yellow.bold(), format!("{:>8}", format!("#{}", number)))),
							None => String::new(),
						}
					},
					paint(Cyan.bold(), format!("{:2}", sync_info.num_active_peers)),
					paint(Cyan.bold(), format!("{:2}", sync_info.num_peers)),
					paint(Cyan.bold(), format!("{:2}", sync_info.current_max_peers(net_config.min_peers, net_config.max_peers))),
				),
				_ => String::new(),
			},
			format!("{} db {} chain {} queue{}",
				paint(Blue.bold(), format!("{:>8}", format_bytes(report.state_db_mem))),
				paint(Blue.bold(), format!("{:>8}", format_bytes(cache_info.total()))),
				paint(Blue.bold(), format!("{:>8}", format_bytes(queue_info.mem_used))),
				match sync_status {
					Some(ref sync_info) => format!(" {} sync", paint(Blue.bold(), format!("{:>8}", format_bytes(sync_info.mem_used)))),
					_ => String::new(),
				}
			),
			match rpc_stats {
				Some(ref rpc_stats) => format!(
					"RPC: {} conn, {} req/s, {} µs",
					paint(Blue.bold(), format!("{:2}", rpc_stats.sessions())),
					paint(Blue.bold(), format!("{:2}", rpc_stats.requests_rate())),
					paint(Blue.bold(), format!("{:3}", rpc_stats.approximated_roundtrip())),
				),
				_ => String::new(),
			},
		);

		*write_report = Some(report);
	}
}

impl ChainNotify for Informant {
	fn new_blocks(&self, imported: Vec<H256>, _invalid: Vec<H256>, _enacted: Vec<H256>, _retracted: Vec<H256>, _sealed: Vec<H256>, _proposed: Vec<Bytes>, duration: u64) {
		let mut last_import = self.last_import.lock();
		let sync_state = self.sync.as_ref().map(|s| s.status().state);
		let importing = is_major_importing(sync_state, self.client.queue_info());
		let ripe = Instant::now() > *last_import + Duration::from_secs(1) && !importing;
		let txs_imported = imported.iter()
			.take(imported.len().saturating_sub(if ripe { 1 } else { 0 }))
			.filter_map(|h| self.client.block(BlockId::Hash(*h)))
			.map(|b| b.transactions_count())
			.sum();

		if ripe {
			if let Some(block) = imported.last().and_then(|h| self.client.block(BlockId::Hash(*h))) {
				let header_view = block.header_view();
				let size = block.rlp().as_raw().len();
				let (skipped, skipped_txs) = (self.skipped.load(AtomicOrdering::Relaxed) + imported.len() - 1, self.skipped_txs.load(AtomicOrdering::Relaxed) + txs_imported);
				info!(target: "import", "Imported {} {} ({} txs, {} Mgas, {} ms, {} KiB){}",
					Colour::White.bold().paint(format!("#{}", header_view.number())),
					Colour::White.bold().paint(format!("{}", header_view.hash())),
					Colour::Yellow.bold().paint(format!("{}", block.transactions_count())),
					Colour::Yellow.bold().paint(format!("{:.2}", header_view.gas_used().low_u64() as f32 / 1000000f32)),
					Colour::Purple.bold().paint(format!("{:.2}", duration as f32 / 1000000f32)),
					Colour::Blue.bold().paint(format!("{:.2}", size as f32 / 1024f32)),
					if skipped > 0 {
						format!(" + another {} block(s) containing {} tx(s)",
							Colour::Red.bold().paint(format!("{}", skipped)),
							Colour::Red.bold().paint(format!("{}", skipped_txs))
						)
					} else {
						String::new()
					}
				);
				self.skipped.store(0, AtomicOrdering::Relaxed);
				self.skipped_txs.store(0, AtomicOrdering::Relaxed);
				*last_import = Instant::now();
			}
		} else {
			self.skipped.fetch_add(imported.len(), AtomicOrdering::Relaxed);
			self.skipped_txs.fetch_add(txs_imported, AtomicOrdering::Relaxed);
		}
	}
}

const INFO_TIMER: TimerToken = 0;

impl IoHandler<ClientIoMessage> for Informant {
	fn initialize(&self, io: &IoContext<ClientIoMessage>) {
		io.register_timer(INFO_TIMER, 5000).expect("Error registering timer");
	}

	fn timeout(&self, _io: &IoContext<ClientIoMessage>, timer: TimerToken) {
		if timer == INFO_TIMER && !self.in_shutdown.load(AtomicOrdering::SeqCst) {
			self.tick();
		}
	}
}