gsender

/*
 * Copyright (C) 2021 Sienci Labs Inc.
 *
 * This file is part of gSender.
 *
 * gSender 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, under version 3 of the License.
 *
 * gSender 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 gSender.  If not, see <https://www.gnu.org/licenses/>.
 *
 * Contact for information regarding this program and its license
 * can be sent through gSender@sienci.com or mailed to the main office
 * of Sienci Labs Inc. in Waterloo, Ontario, Canada.
 *
 */

/* eslint max-classes-per-file: 0 */
import events from "node:events";
import logger from "./logger";
import { checkIfRotaryFile } from "./rotary";

export const SP_TYPE_SEND_RESPONSE = 0;
export const SP_TYPE_CHAR_COUNTING = 1;

const log = logger("controller:Grbl");

const noop = () => {};

class SPSendResponse {
	callback = null;

	constructor(options, callback = noop) {
		if (typeof options === "function") {
			callback = options;
			options = {};
		}
		if (typeof callback === "function") {
			this.callback = callback;
		}
	}

	process() {
		this.callback?.(this);
	}

	clear() {
		// Do nothing
	}

	get type() {
		return SP_TYPE_SEND_RESPONSE;
	}
}

class SPCharCounting {
	callback = null;

	state = {
		bufferSize: 128, // Defaults to 128
		dataLength: 0,
		queue: [],
		line: "",
	};

	constructor(options, callback = noop) {
		if (typeof options === "function") {
			callback = options;
			options = {};
		}

		// bufferSize
		const bufferSize = Number(options.bufferSize);
		if (bufferSize && bufferSize > 0) {
			this.state.bufferSize = bufferSize;
		}

		if (typeof callback === "function") {
			this.callback = callback;
		}
	}

	process(isOk) {
		this.callback?.(this, isOk);
	}

	reset() {
		this.state.bufferSize = 128; // Defaults to 128
		this.state.dataLength = 0;
		this.state.queue = [];
		this.state.line = "";
	}

	clear() {
		this.state.dataLength = 0;
		this.state.queue = [];
		this.state.line = "";
	}

	get type() {
		return SP_TYPE_CHAR_COUNTING;
	}

	get bufferSize() {
		return this.state.bufferSize;
	}

	set bufferSize(bufferSize = 0) {
		bufferSize = Number(bufferSize);
		if (!bufferSize) {
			return;
		}

		// The buffer size cannot be reduced below the size of the data within the buffer.
		this.state.bufferSize = Math.max(bufferSize, this.state.dataLength);
	}

	get dataLength() {
		return this.state.dataLength;
	}

	set dataLength(dataLength) {
		this.state.dataLength = dataLength;
	}

	get queue() {
		return this.state.queue;
	}

	set queue(queue) {
		this.state.queue = queue;
	}

	get line() {
		return this.state.line;
	}

	set line(line) {
		this.state.line = line;
	}
}

class Sender extends events.EventEmitter {
	// streaming protocol
	sp = null;

	state = {
		hold: false,
		holdReason: null,
		name: "",
		gcode: "",
		context: {},
		lines: [],
		total: 0,
		sent: 0,
		received: 0,
		startTime: 0,
		finishTime: 0,
		elapsedTime: 0,
		remainingTime: 0,
		toolChanges: 0,
		estimatedTime: 0,
		estimateData: [],
		ovF: 100,
		countdownQueue: [],
		totalSentToQueue: 0,
		queueDone: true,
		timer: 0,
		countdownIsPaused: false,
		isRotaryFile: false,
	};

	stateChanged = false;

	dataFilter = null;

	countDownID = null;

	checkIntervalID = null;

	// @param {number} [type] Streaming protocol type. 0 for send-response, 1 for character-counting.
	// @param {object} [options] The options object.
	// @param {number} [options.bufferSize] The buffer size used in character-counting streaming protocol. Defaults to 127.
	// @param {function} [options.dataFilter] A function to be used to handle the data. The function accepts two arguments: The data to be sent to the controller, and the context.
	constructor(type = SP_TYPE_SEND_RESPONSE, options = {}) {
		super();

		if (typeof options.dataFilter === "function") {
			this.dataFilter = options.dataFilter;
		}

		// character-counting
		if (type === SP_TYPE_CHAR_COUNTING) {
			this.sp = new SPCharCounting(options, (sp, isOk) => {
				// only remove line length from buffer if ok was sent
				if (sp.queue.length > 0 && isOk) {
					const lineLength = sp.queue.shift();
					sp.dataLength -= lineLength;
				}

				while (!this.state.hold && this.state.sent < this.state.total) {
					// Remove leading and trailing whitespace from both ends of a string.
					// Only load and filter a fresh line when sp.line is empty; if sp.line is
					// already set, it was cached from a previous iteration where the buffer
					// was full — re-running dataFilter would double-remap tool numbers.
					if (!sp.line) {
						sp.line = this.state.lines[this.state.sent].trim();
						if (this.dataFilter) {
							sp.line = this.dataFilter(sp.line, this.state.context) || "";
						}
					}

					// The newline character (\n) consumed the RX buffer space
					if (
						sp.line.length > 0 &&
						sp.dataLength + sp.line.length + 1 >= sp.bufferSize
					) {
						break;
					}

					this.state.sent++;
					this.emit("change");

					if (sp.line.length === 0) {
						this.ack(); // ack empty line
						continue;
					}

					const line = `${sp.line}\n`;
					sp.line = "";
					sp.dataLength += line.length;
					sp.queue.push(line.length);
					this.emit("data", line, this.state.context);
				}
			});
		}

		// send-response
		if (type === SP_TYPE_SEND_RESPONSE) {
			this.sp = new SPSendResponse(options, (_sp) => {
				while (!this.state.hold && this.state.sent < this.state.total) {
					// Remove leading and trailing whitespace from both ends of a string
					let line = this.state.lines[this.state.sent].trim();

					if (this.dataFilter) {
						line = this.dataFilter(line, this.state.context) || "";
					}

					this.state.sent++;
					this.emit("change");

					if (line.length === 0) {
						this.ack(); // ack empty line
						continue;
					}

					this.emit("data", `${line}\n`, this.state.context);
					break;
				}
			});
		}

		this.on("change", () => {
			this.stateChanged = true;
		});
	}

	getContext() {
		return this.state.context;
	}

	toJSON() {
		return {
			sp: this.sp.type,
			hold: this.state.hold,
			holdReason: this.state.holdReason,
			name: this.state.name,
			context: this.state.context,
			size: this.state.gcode.length,
			total: this.state.total,
			sent: this.state.sent,
			received: this.state.received,
			startTime: this.state.startTime,
			finishTime: this.state.finishTime,
			elapsedTime: this.state.elapsedTime,
			timePaused: this.state.timePaused,
			timeRunning: this.state.timeRunning,
			remainingTime: this.state.remainingTime,
			toolChanges: this.state.toolChanges,
			bufferSize: this.state.bufferSize,
			dataLength: this.state.dataLength,
			estimatedTime: this.state.estimatedTime,
			ovF: this.state.ovF,
			isRotaryFile: this.state.isRotaryFile,
			currentLineRunning:
				this.state.totalSentToQueue - this.state.countdownQueue.length,
		};
	}

	hold(reason) {
		if (this.state.hold) {
			return;
		}
		this.state.hold = true;
		this.state.holdReason = reason;
		// this.state.timePaused = new Date().getTime();
		this.emit("hold");
		this.emit("change");
	}

	unhold() {
		if (!this.state.hold) {
			return;
		}
		this.state.hold = false;
		this.state.holdReason = null;
		// this.state.timePaused = new Date().getTime() - this.state.timePaused;
		this.emit("unhold");
		this.emit("change");
	}

	// @return {boolean} Returns true on success, false otherwise.
	load(name, gcode = "", context = {}) {
		if (typeof gcode !== "string" || !gcode) {
			return false;
		}

		let lines = gcode.split("\n");
		lines = lines.filter((line) => line.trim().length > 0);

		if (this.sp) {
			this.sp.clear();
		}
		this.state.hold = false;
		this.state.holdReason = null;
		this.state.name = name;
		this.state.gcode = gcode;
		this.state.context = context;
		this.state.lines = lines;
		this.state.total = this.state.lines.length;
		this.state.sent = 0;
		this.state.received = 0;
		this.state.startTime = 0;
		this.state.finishTime = 0;
		this.state.elapsedTime = 0;
		this.state.timePaused = 0;
		this.state.timeRunning = 0;
		this.state.remainingTime = 0;
		this.state.toolChanges = 0;
		this.state.estimatedTime = 0;
		this.state.estimateData = [];
		this.state.countdownQueue = [];
		this.state.totalSentToQueue = 0;
		this.state.queueDone = true;

		// check if file is rotary
		this.state.isRotaryFile = checkIfRotaryFile(gcode);

		this.emit("load", name, gcode, context);
		log.debug("sender requesting");
		this.emit("requestData");
		this.emit("change");

		return true;
	}

	unload() {
		if (this.sp) {
			this.sp.clear();
		}
		this.state.hold = false;
		this.state.holdReason = null;
		this.state.name = "";
		this.state.gcode = "";
		this.state.context = {};
		this.state.lines = [];
		this.state.total = 0;
		this.state.sent = 0;
		this.state.received = 0;
		this.state.startTime = 0;
		this.state.finishTime = 0;
		this.state.elapsedTime = 0;
		this.state.timePaused = 0;
		this.state.timeRunning = 0;
		this.state.remainingTime = 0;
		this.state.toolChanges = 0;
		this.state.estimatedTime = 0;
		this.state.estimateData = [];
		this.state.countdownQueue = [];
		this.state.totalSentToQueue = 0;
		this.state.queueDone = true;
		this.state.isRotaryFile = false;

		this.emit("unload");
		this.emit("change");
	}

	// Tells the sender an acknowledgement has received.
	// @return {boolean} Returns true on success, false otherwise.
	ack() {
		if (!this.state.gcode) {
			return false;
		}

		if (this.state.received >= this.state.sent) {
			return false;
		}

		this.state.received++;
		this.emit("change");

		return true;
	}

	setStartLine(line = 0) {
		this.state.sent = line;
		this.state.received = line;
	}

	// Tells the sender to send more data.
	// @return {boolean} Returns true on success, false otherwise.
	next(options = {}) {
		const { startFromLine, timePaused, forceEnd, isOk } = options;

		if (!this.state.gcode) {
			return false;
		}

		const now = Date.now();

		const handleStart = () => {
			this.state.startTime = now;
			this.state.finishTime = 0;
			this.state.elapsedTime = 0;
			this.state.timePaused = 0;
			this.state.timeRunning = 0;
			// make sure time is up to date will current ovF
			this.state.remainingTime =
				this.state.estimatedTime / (this.state.ovF / 100);
			this.state.countdownQueue = [];
			this.state.totalSentToQueue = 0;
			this.state.queueDone = true;
			this.state.countdownIsPaused = false;

			// catch up time estimation for start from line
			if (startFromLine) {
				this.state.totalSentToQueue = this.state.received;
				for (let i = 0; i <= this.state.received; i++) {
					this.state.remainingTime -=
						Number(this.state.estimateData[i] || 0) / (this.state.ovF / 100);
				}
			}
			if (!this.isRotaryFile) {
				// used to initially start the countdown, and also in case the queue finishes but lines still need to be sent
				this.checkIntervalID = setInterval(() => {
					if (this.state.countdownQueue.length > 0 && this.state.queueDone) {
						this.state.queueDone = false;
						this.fakeCountdown();
					}
				}, 100);
			}

			this.emit("start", this.state.startTime);
			this.emit("change");
		};
		if (startFromLine) {
			handleStart();
		} else if (this.state.total > 0 && this.state.sent === 0) {
			this.state.received = 0;
			handleStart();
		}

		if (timePaused) {
			this.state.timePaused += timePaused - 1000; // subtracted one second here to account for the time it takes for the sender to hold/unhold
		}

		if (this.sp) {
			this.sp.process(isOk);
		}

		// Elapsed Time
		this.updateElapsedTime();

		if (this.state.received > 0) {
			if (this.state.estimatedTime > 0) {
				// in case smth goes wrong with the estimate, don't want to show negative time
				if (this.state.received < this.state.estimateData.length) {
					// add the lines to the queue from where we left off to the current number received
					for (
						let i = this.state.totalSentToQueue;
						i <= this.state.received;
						i++
					) {
						this.state.countdownQueue.push(
							Number(this.state.estimateData[i] || 0),
						);
						this.state.totalSentToQueue++;
					}
				}
			}
		}

		if (this.state.received >= this.state.total || forceEnd) {
			if (this.state.finishTime === 0) {
				// avoid issue 'end' multiple times
				this.state.finishTime = now;
				this.emit("end", this.state.finishTime);
				this.emit("change");
			}
		}

		return true;
	}

	fakeCountdown() {
		// skip lines that take no time
		while (this.state.timer === 0) {
			if (this.state.countdownQueue.length === 0) {
				this.stopCountdown();
				return;
			}
			this.state.timer =
				this.state.countdownQueue.shift() / (this.state.ovF / 100);
		}
		// if less than 1 sec left, create timeout instead of interval
		if (this.state.timer < 1) {
			this.countDownID = setTimeout(() => {
				if (!this.state.countdownIsPaused) {
					this.state.remainingTime -= this.state.timer;
					this.state.remainingTime = this.state.remainingTime.toFixed(4);
					this.state.timer = 0;
					this.updateElapsedTime();
					this.emit("change");
					this.fakeCountdown();
				} else {
					this.state.queueDone = true;
				}
			}, this.state.timer * 1000);
		} else {
			// if more than one second, make interval
			this.countDownID = setInterval(() => {
				if (!this.state.countdownIsPaused) {
					this.state.timer--;
					this.state.remainingTime--;
					this.updateElapsedTime();

					if (this.state.timer < 1) {
						clearInterval(this.countDownID);
						this.fakeCountdown();
					}
					this.emit("change");
				}
			}, 1000);
		}
	}

	// Rewinds the internal array pointer.
	// @return {boolean} Returns true on success, false otherwise.
	rewind() {
		if (!this.state.gcode) {
			return false;
		}

		if (this.sp) {
			this.sp.clear();
		}
		this.state.hold = false; // clear hold off state
		this.state.holdReason = null;
		this.state.sent = 0;
		this.state.received = 0;
		this.state.toolChanges = 0;
		this.state.countdownQueue = [];
		this.state.totalSentToQueue = 0;
		clearInterval(this.checkIntervalID);
		this.emit("change");

		return true;
	}

	// Checks if there are any state changes. It also clears the stateChanged flag.
	// @return {boolean} Returns true on state changes, false otherwise.
	peek() {
		const stateChanged = this.stateChanged;
		this.stateChanged = false;
		return stateChanged;
	}

	incrementToolChanges() {
		this.state.toolChanges = this.state.toolChanges + 1;
		this.emit("change");
		return this.state.toolChanges;
	}

	setEstimateData(estimates) {
		this.state.estimateData = estimates;
	}

	setEstimatedTime(estimatedTime) {
		this.state.remainingTime = Number(estimatedTime);
		this.state.estimatedTime = Number(estimatedTime);
	}

	setOvF(ovF) {
		if (this.state.ovF !== 100) {
			this.state.remainingTime *= this.state.ovF / 100; // reset to 100%
		}
		this.state.remainingTime /= ovF / 100; // set to new time
		this.state.ovF = ovF;
	}

	resumeCountdown() {
		this.state.countdownIsPaused = false;
	}

	pauseCountdown() {
		this.state.countdownIsPaused = true;
	}

	stopCountdown() {
		clearInterval(this.countDownID);
		this.state.queueDone = true;
		this.state.remainingTime -= this.state.timer;
	}

	isCountdownRunning() {
		return this.state.countdownIsPaused;
	}

	updateElapsedTime() {
		// Elapsed Time
		const now = Date.now();
		this.state.elapsedTime = now - this.state.startTime;
		this.state.timeRunning = this.state.elapsedTime - this.state.timePaused;
	}
}

export default Sender;