// Copyright 2017 Parity Technologies (UK) Ltd.
// This file is part of Substrate Demo.

// Substrate Demo 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.

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

//! Substrate Demo CLI library.

#![warn(missing_docs)]

extern crate ctrlc;
extern crate ed25519;
extern crate env_logger;
extern crate futures;
extern crate tokio_core;
extern crate triehash;
extern crate substrate_client as client;
extern crate substrate_codec as codec;
extern crate substrate_primitives as primitives;
extern crate substrate_rpc;
extern crate substrate_rpc_servers as rpc;
extern crate substrate_runtime_io as runtime_io;
extern crate substrate_state_machine as state_machine;
extern crate demo_executor;
extern crate demo_primitives;
extern crate demo_runtime;

#[macro_use]
extern crate hex_literal;
#[macro_use]
extern crate clap;
#[macro_use]
extern crate error_chain;
#[macro_use]
extern crate log;

pub mod error;

use std::sync::Arc;
use client::genesis;
use codec::Slicable;
use demo_runtime::{GenesisConfig, ConsensusConfig, CouncilConfig, DemocracyConfig,
	SessionConfig, StakingConfig, BuildExternalities};
use futures::{Future, Sink, Stream};


struct DummyPool;
impl substrate_rpc::author::AuthorApi for DummyPool {
	fn submit_extrinsic(&self, _: primitives::block::Extrinsic) -> substrate_rpc::author::error::Result<()> {
		Err(substrate_rpc::author::error::ErrorKind::Unimplemented.into())
	}
}

struct DummySystem;
impl substrate_rpc::system::SystemApi for DummySystem {
	fn system_name(&self) -> substrate_rpc::system::error::Result<String> {
		Ok("substrate-demo".into())
	}
	fn system_version(&self) -> substrate_rpc::system::error::Result<String> {
		Ok(crate_version!().into())
	}
	fn system_chain(&self) -> substrate_rpc::system::error::Result<String> {
		Ok("default".into())
	}
}

/// Parse command line arguments and start the node.
///
/// IANA unassigned port ranges that we could use:
/// 6717-6766		Unassigned
/// 8504-8553		Unassigned
/// 9556-9591		Unassigned
/// 9803-9874		Unassigned
/// 9926-9949		Unassigned
pub fn run<I, T>(args: I) -> error::Result<()> where
	I: IntoIterator<Item = T>,
	T: Into<std::ffi::OsString> + Clone,
{
	let yaml = load_yaml!("./cli.yml");
	let matches = clap::App::from_yaml(yaml).version(crate_version!()).get_matches_from_safe(args)?;

	// TODO [ToDr] Split parameters parsing from actual execution.
	let log_pattern = matches.value_of("log").unwrap_or("");
	init_logger(log_pattern);

	// Create client
	let executor = demo_executor::Executor::new();

	struct GenesisBuilder;

	impl client::GenesisBuilder for GenesisBuilder {
		fn build(self) -> (primitives::Header, Vec<(Vec<u8>, Vec<u8>)>) {
			let god_key = hex!["3d866ec8a9190c8343c2fc593d21d8a6d0c5c4763aaab2349de3a6111d64d124"];
			let genesis_config = GenesisConfig {
				consensus: Some(ConsensusConfig {
					code: vec![],	// TODO
					authorities: vec![god_key.clone()],
				}),
				system: None,
		//		block_time: 5,			// 5 second block time.
				session: Some(SessionConfig {
					validators: vec![god_key.clone()],
					session_length: 720,	// that's 1 hour per session.
				}),
				staking: Some(StakingConfig {
					current_era: 0,
					intentions: vec![],
					transaction_fee: 100,
					balances: vec![(god_key.clone(), 1u64 << 63)].into_iter().collect(),
					validator_count: 12,
					sessions_per_era: 24,	// 24 hours per era.
					bonding_duration: 90,	// 90 days per bond.
				}),
				democracy: Some(DemocracyConfig {
					launch_period: 120 * 24 * 14,	// 2 weeks per public referendum
					voting_period: 120 * 24 * 28,	// 4 weeks to discuss & vote on an active referendum
					minimum_deposit: 1000,	// 1000 as the minimum deposit for a referendum
				}),
				council: Some(CouncilConfig {
					active_council: vec![],
					candidacy_bond: 1000,	// 1000 to become a council candidate
					voter_bond: 100,		// 100 down to vote for a candidate
					present_slash_per_voter: 1,	// slash by 1 per voter for an invalid presentation.
					carry_count: 24,		// carry over the 24 runners-up to the next council election
					presentation_duration: 120 * 24,	// one day for presenting winners.
					approval_voting_period: 7 * 120 * 24,	// one week period between possible council elections.
					term_duration: 180 * 120 * 24,	// 180 day term duration for the council.
					desired_seats: 0, // start with no council: we'll raise this once the stake has been dispersed a bit.
					inactive_grace_period: 1,	// one addition vote should go by before an inactive voter can be reaped.

					cooloff_period: 90 * 120 * 24, // 90 day cooling off period if council member vetoes a proposal.
					voting_period: 7 * 120 * 24, // 7 day voting period for council members.
				}),
			};

			let storage = genesis_config.build_externalities();
			let block = genesis::construct_genesis_block(&storage);
			(primitives::block::Header::decode(&mut block.header.encode().as_ref()).expect("to_vec() always gives a valid serialisation; qed"), storage.into_iter().collect())
		}
	}

	let client = Arc::new(client::new_in_mem(executor, GenesisBuilder)?);
	let mut core = ::tokio_core::reactor::Core::new().expect("Unable to spawn event loop.");

	let _rpc_servers = {
		let handler = || {
			let chain = rpc::apis::chain::Chain::new(client.clone(), core.remote());
			rpc::rpc_handler(client.clone(), chain, DummyPool, DummySystem)
		};
		let http_address = "127.0.0.1:9933".parse().unwrap();
		let ws_address = "127.0.0.1:9944".parse().unwrap();

		(
			rpc::start_http(&http_address, handler())?,
			rpc::start_ws(&ws_address, handler())?
		)
	};

	if let Some(_) = matches.subcommand_matches("validator") {
		info!("Starting validator.");
		let (exit_send, exit) = futures::sync::mpsc::channel(1);
		ctrlc::CtrlC::set_handler(move || {
			exit_send.clone().send(()).wait().expect("Error sending exit notification");
		});
		core.run(exit.into_future()).expect("Error running informant event loop");
		return Ok(())
	}

	println!("No command given.\n");
	let _ = clap::App::from_yaml(yaml).print_long_help();

	Ok(())
}

fn init_logger(pattern: &str) {
	let mut builder = env_logger::LogBuilder::new();
	// Disable info logging by default for some modules:
	builder.filter(Some("hyper"), log::LogLevelFilter::Warn);
	// Enable info for others.
	builder.filter(None, log::LogLevelFilter::Info);

	if let Ok(lvl) = std::env::var("RUST_LOG") {
		builder.parse(&lvl);
	}

	builder.parse(pattern);


	builder.init().expect("Logger initialized only once.");
}