// Gupax - GUI Uniting P2Pool And XMRig
//
// Copyright (c) 2022 hinto-janaiyo
//
// This program 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.
//
// This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.

use serde_derive::{Serialize,Deserialize};
use std::time::{Instant,Duration};
use std::collections::HashMap;
use std::error::Error;
use std::thread;
use egui::Color32;
use rand::Rng;
use log::*;

// Community Monerod nodes. All of these have ZMQ on 18083.
// Adding/removing nodes will need changes to pretty
// much all the code in this file, and the code that
// handles the actual Enum selector in the P2Pool tab.
pub const C3POOL: &'static str = "node.c3pool.com:18081";
pub const CAKE: &'static str = "xmr-node.cakewallet.com:18081";
pub const CAKE_EU: &'static str = "xmr-node-eu.cakewallet.com:18081";
pub const CAKE_UK: &'static str = "xmr-node-uk.cakewallet.com:18081";
pub const CAKE_US: &'static str = "xmr-node-usa-east.cakewallet.com:18081";
pub const MONERUJO: &'static str = "nodex.monerujo.io:18081";
pub const RINO: &'static str = "node.community.rino.io:18081";
pub const SELSTA: &'static str = "selsta1.featherwallet.net:18081";
pub const SETH: &'static str = "node.sethforprivacy.com:18089";
pub const SUPPORTXMR: &'static str = "node.supportxmr.com:18081";
pub const SUPPORTXMR_IR: &'static str = "node.supportxmr.ir:18081";
pub const XMRVSBEAST: &'static str = "p2pmd.xmrvsbeast.com:18081";

pub const NODE_IPS: [&'static str; 12] = [
	C3POOL,CAKE,CAKE_EU,CAKE_UK,CAKE_US,MONERUJO,RINO,
	SELSTA,SETH,SUPPORTXMR,SUPPORTXMR_IR,XMRVSBEAST,
];

#[derive(Debug)]
pub struct NodeStruct {
	c3pool: Data, cake: Data, cake_eu: Data, cake_uk: Data, cake_us: Data, monerujo: Data,
	rino: Data, selsta: Data, seth: Data, supportxmr: Data, supportxmr_ir: Data, xmrvsbeast: Data,
}

#[derive(Debug)]
pub struct Data {
	pub ms: u128,
	pub color: Color32,
	pub id: NodeEnum,
	pub ip: &'static str,
}

#[derive(Copy,Clone,Eq,PartialEq,Debug,Deserialize,Serialize)]
pub enum NodeEnum {
	C3pool, Cake, CakeEu, CakeUk, CakeUs, Monerujo, Rino,
	Selsta, Seth, SupportXmr, SupportXmrIr, XmrVsBeast,
}

impl std::fmt::Display for NodeEnum {
	fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
		write!(f, "{:#?}", self)
	}
}

#[derive(Debug)]
pub struct PingResult {
	pub nodes: NodeStruct,
	pub fastest: NodeEnum,
}

use crate::NodeEnum::*;
impl NodeStruct {
	pub fn default() -> Self {
		let ms = 0;
		let color = Color32::GRAY;
		Self {
			c3pool:        Data { ms, color, id: C3pool,       ip: C3POOL, },
			cake:          Data { ms, color, id: Cake,         ip: CAKE, },
			cake_eu:       Data { ms, color, id: CakeEu,       ip: CAKE_EU, },
			cake_uk:       Data { ms, color, id: CakeUk,       ip: CAKE_UK, },
			cake_us:       Data { ms, color, id: CakeUs,       ip: CAKE_US, },
			monerujo:      Data { ms, color, id: Monerujo,     ip: MONERUJO, },
			rino:          Data { ms, color, id: Rino,         ip: RINO, },
			selsta:        Data { ms, color, id: Selsta,       ip: SELSTA, },
			seth:          Data { ms, color, id: Seth,         ip: SETH, },
			supportxmr:    Data { ms, color, id: SupportXmr,   ip: SUPPORTXMR, },
			supportxmr_ir: Data { ms, color, id: SupportXmrIr, ip: SUPPORTXMR_IR, },
			xmrvsbeast:    Data { ms, color, id: XmrVsBeast,   ip: XMRVSBEAST, },
		}
	}

	// This is for pinging the community nodes to
	// find the fastest/slowest one for the user.
	// The process:
	//   - Send [get_info] JSON-RPC requests over HTTP
	//   - To prevent fingerprinting, randomly send [2-4] calls
	//   - Measure each request in milliseconds as [u128]
	//   - Timeout on requests over 5 seconds
	//   - Calculate average time
	//   - Add data to appropriate struct
	//   - Sort fastest to lowest
	//   - Return [PingResult(NodeStruct, NodeEnum)] (data and fastest node)
 	//
	// This is done linearly since per IP since
	// multi-threading might affect performance.
	//
	// <300ms  = GREEN
	// <1000ms = YELLOW
	// >1000ms = RED
	// timeout = BLACK
	// default = GRAY
	pub fn ping() -> PingResult {
		info!("Starting community node pings...");
		// Get node list
		let mut nodes = NodeStruct::default();

		// Create JSON request
		let mut get_info = HashMap::new();
		get_info.insert("jsonrpc", "2.0");
		get_info.insert("id", "0");
		get_info.insert("method", "get_info");

		// Misc Settings
		let mut vec: Vec<(u128, NodeEnum)> = Vec::new();

		// Create HTTP Client
		let timeout_sec = Duration::from_millis(5000);
		let client = reqwest::blocking::ClientBuilder::new();
		let client = reqwest::blocking::ClientBuilder::timeout(client, timeout_sec);
		let client = reqwest::blocking::ClientBuilder::build(client).unwrap();

		for ip in NODE_IPS.iter() {
			// Match IP
			let id = match *ip {
				C3POOL        => C3pool,
				CAKE          => Cake,
				CAKE_EU       => CakeEu,
				CAKE_UK       => CakeUk,
				CAKE_US       => CakeUs,
				MONERUJO      => Monerujo,
				RINO          => Rino,
				SELSTA        => Selsta,
				SETH          => Seth,
				SUPPORTXMR    => SupportXmr,
				SUPPORTXMR_IR => SupportXmrIr,
				_ => XmrVsBeast,
			};
			// Misc
			let mut timeout = false;
			let mut mid = Duration::new(0, 0);
			let max = rand::thread_rng().gen_range(2..4);

			// Start JSON-RPC request
			for i in 1..=max {
				let now = Instant::now();
				let http = "http://".to_owned() + &**ip + "/json_rpc";
				match client.post(http).json(&get_info).send() {
					Ok(_) => mid += now.elapsed(),
					Err(err) => {
						error!("Timeout on [{:#?}: {}] (over 5 seconds) | {}", id, ip, err);
						mid += timeout_sec;
						timeout = true;
					},
				};
			}

			// Calculate average
			let ms = mid.as_millis() / 3;
			vec.push((ms, id));
			info!("{}ms ... {} calls ... {}", ms, max, ip);
			let color: Color32;
			if timeout == true {
				color = Color32::BLACK
			} else if ms >= 1000 {
				color = Color32::LIGHT_RED
			} else if ms >= 300 {
				color = Color32::LIGHT_YELLOW
			} else {
				color = Color32::LIGHT_GREEN
			}
			match id {
				C3pool       => { nodes.c3pool.ms = ms; nodes.c3pool.color = color; },
				Cake         => { nodes.cake.ms = ms; nodes.cake.color = color; },
				CakeEu       => { nodes.cake_eu.ms = ms; nodes.cake_eu.color = color; },
				CakeUk       => { nodes.cake_uk.ms = ms; nodes.cake_uk.color = color; },
				CakeUs       => { nodes.cake_us.ms = ms; nodes.cake_us.color = color; },
				Monerujo     => { nodes.monerujo.ms = ms; nodes.monerujo.color = color; },
				Rino         => { nodes.rino.ms = ms; nodes.rino.color = color; },
				Selsta       => { nodes.selsta.ms = ms; nodes.selsta.color = color; },
				Seth         => { nodes.seth.ms = ms; nodes.seth.color = color; },
				SupportXmr   => { nodes.supportxmr.ms = ms; nodes.supportxmr.color = color; },
				SupportXmrIr => { nodes.supportxmr_ir.ms = ms; nodes.supportxmr_ir.color = color; },
				XmrVsBeast   => { nodes.xmrvsbeast.ms = ms; nodes.xmrvsbeast.color = color; },
			}
		}

		// Calculate fastest out of all nodes
		let mut best_ms: u128 = vec[0].0;
		let mut fastest: NodeEnum = vec[0].1;
		for (ms, id) in vec.iter() {
			if ms < &best_ms {
				fastest = *id;
				best_ms = *ms;
			}
		}
		// These values have weird behavior.
		// The values don't update if not printed beforehand,
		// so the match below on [fastest] gets funky.
		info!("Fastest node ... {:#?} @ {:#?}ms", fastest, best_ms);
		info!("Community node ping ... OK");
		PingResult { nodes, fastest, }
	}
}