// Copyright 2021 The Grin Developers
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/// Grin server commands processing
use std::process::exit;
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread;
use std::time::Duration;

use clap::ArgMatches;

use crate::config::GlobalConfig;
use crate::p2p::Seeding;
use crate::servers;
use crate::tui::ui;
use futures::channel::oneshot;
use grin_p2p::msg::PeerAddrs;
use grin_p2p::PeerAddr;
use grin_servers::common::types::ServerInitStatus;
use grin_servers::Server;
use grin_util::logger::LogEntry;
use grin_util::StopState;
use std::sync::mpsc;

/// wrap below to allow UI to clean up on stop
pub fn start_server(
	config: servers::ServerConfig,
	logs_rx: Option<mpsc::Receiver<LogEntry>>,
	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
) {
	exit(start_server_tui(config, logs_rx, api_chan));
}

fn start_server_tui(
	config: servers::ServerConfig,
	logs_rx: Option<mpsc::Receiver<LogEntry>>,
	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
) -> i32 {
	if config.run_tui.unwrap_or(false) {
		warn!("Starting GRIN in UI mode...");
		// Run the UI controller.
		let (serv_tx, serv_rx) = mpsc::channel::<ServerInitStatus>();
		let mut controller = ui::Controller::new(logs_rx, serv_rx).unwrap_or_else(|e| {
			panic!("Error loading UI controller: {}", e);
		});
		let serv_tx_clone = serv_tx.clone();
		let stop_state = Arc::new(StopState::new());
		let stop_state_clone = stop_state.clone();
		thread::spawn(move || {
			match Server::start(
				config,
				Some(stop_state_clone.clone()),
				Some(serv_tx_clone.clone()),
				api_chan,
			) {
				Ok(s) => {
					if stop_state_clone.is_stopped() {
						s.stop();
						return;
					}
					let _ = serv_tx_clone.send(ServerInitStatus::FinishedLoading(s));
				}
				Err(e) => {
					let _ = serv_tx_clone.send(ServerInitStatus::ErrorLoading(e));
				}
			}
		});
		let exit_code = controller.run();
		stop_state.stop();
		exit_code
	} else {
		warn!("Starting GRIN w/o UI...");
		match Server::start(config, None, None, api_chan) {
			Ok(s) => {
				let running = Arc::new(AtomicBool::new(true));
				let r = running.clone();
				ctrlc::set_handler(move || {
					r.store(false, Ordering::SeqCst);
				})
				.expect("Error setting handler for both SIGINT (Ctrl+C) and SIGTERM (kill)");
				while running.load(Ordering::SeqCst) {
					thread::sleep(Duration::from_secs(1));
				}
				warn!("Received SIGINT (Ctrl+C) or SIGTERM (kill).");
				s.stop();
				0
			}
			Err(e) => {
				error!("Error starting GRIN: {:?}", e);
				1
			}
		}
	}
}

/// Handles the server part of the command line, mostly running, starting and
/// stopping the Grin blockchain server. Processes all the command line
/// arguments to build a proper configuration and runs Grin with that
/// configuration.
pub fn server_command(
	server_args: Option<&ArgMatches<'_>>,
	global_config: GlobalConfig,
	logs_rx: Option<mpsc::Receiver<LogEntry>>,
	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
) -> i32 {
	// just get defaults from the global config
	let mut server_config = global_config.members.as_ref().unwrap().server.clone();

	if let Some(a) = server_args {
		if let Some(port) = a.value_of("port") {
			server_config.p2p_config.port = port.parse().unwrap();
		}

		if let Some(api_port) = a.value_of("api_port") {
			let default_ip = "0.0.0.0";
			server_config.api_http_addr = format!("{}:{}", default_ip, api_port);
		}

		if let Some(wallet_url) = a.value_of("wallet_url") {
			server_config
				.stratum_mining_config
				.as_mut()
				.unwrap()
				.wallet_listener_url = wallet_url.to_string();
		}

		if let Some(seeds) = a.values_of("seed") {
			let peers = seeds.filter_map(|s| s.parse().ok()).map(PeerAddr).collect();
			server_config.p2p_config.seeding_type = Seeding::List;
			server_config.p2p_config.seeds = Some(PeerAddrs { peers });
		}
	}

	if let Some(a) = server_args {
		match a.subcommand() {
			("run", _) => {
				start_server(server_config, logs_rx, api_chan);
			}
			("", _) => {
				println!("Subcommand required, use 'grin help server' for details");
			}
			(cmd, _) => {
				println!(":: {:?}", server_args);
				panic!(
					"Unknown server command '{}', use 'grin help server' for details",
					cmd
				);
			}
		}
	} else {
		start_server(server_config, logs_rx, api_chan);
	}
	0
}