/*****************************************************************************
#                                                                            #
#    KVMD - The main PiKVM daemon.                                           #
#                                                                            #
#    Copyright (C) 2018-2024  Maxim Devaev <mdevaev@gmail.com>               #
#                                                                            #
#    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 strict";


import {ROOT_PREFIX} from "../vars.js";
import {tools, $} from "../tools.js";
import {wm} from "../wm.js";

import {Recorder} from "./recorder.js";
import {Hid} from "./hid.js";
import {Paste} from "./paste.js";
import {Atx} from "./atx.js";
import {Msd} from "./msd.js";
import {Streamer} from "./stream.js";
import {Gpio} from "./gpio.js";
import {Ocr} from "./ocr.js";
import {Switch} from "./switch.js";


export function Session() {
	// var self = this;

	/************************************************************************/

	var __ws = null;

	var __ping_timer = null;
	var __missed_heartbeats = 0;

	var __streamer = new Streamer();
	var __recorder = new Recorder();
	var __hid = new Hid(__streamer.getGeometry, __recorder);
	var __paste = new Paste(__recorder);
	var __atx = new Atx(__recorder);
	var __msd = new Msd();
	var __gpio = new Gpio(__recorder);
	var __ocr = new Ocr(__streamer.getGeometry);
	var __switch = new Switch();

	var __info_health_state = null;
	var __info_fan_state = null;

	var __init__ = function() {
		__streamer.ensureDeps(() => __startSession());
	};

	/************************************************************************/

	var __setInfoState = function(state) {
		for (let key of Object.keys(state)) {
			switch (key) {
				case "meta": __setInfoStateMeta(state.meta); break;
				case "health": __setInfoStateHealth(state.health); break;
				case "fan": __setInfoStateFan(state.fan); break;
				case "system": __setInfoStateSystem(state.system); break;
				case "extras": __setInfoStateExtras(state.extras); break;
			}
		}
	};

	var __setInfoStateMeta = function(state) {
		if (state !== null) {
			$("kvmd-meta-json").innerText = JSON.stringify(state, undefined, 4);

			if (state.server && state.server.host) {
				$("kvmd-meta-server-host").innerText = `Server: ${state.server.host}`;
				document.title = `PiKVM Session: ${state.server.host}`;
			} else {
				$("kvmd-meta-server-host").innerText = "";
				document.title = "PiKVM Session";
			}

			for (let place of ["left", "right"]) {
				if (state.tips && state.tips[place]) {
					$(`kvmd-meta-tips-${place}`).innerText = state.tips[place];
				}
			}

			// Don't use this option, it may be removed in any time
			if (state.web && state.web.confirm_session_exit === false) {
				window.onbeforeunload = null; // See main.js
			}
		}
	};

	var __setInfoStateHealth = function(state) {
		if (state.throttling !== null) {
			let flags = state.throttling.parsed_flags;
			let ignore_past = state.throttling.ignore_past;
			let undervoltage = (flags.undervoltage.now || (flags.undervoltage.past && !ignore_past));
			let freq_capped = (flags.freq_capped.now || (flags.freq_capped.past && !ignore_past));

			tools.hidden.setVisible($("hw-health-dropdown"), (undervoltage || freq_capped));
			$("hw-health-undervoltage-led").className = (undervoltage ? (flags.undervoltage.now ? "led-red" : "led-yellow") : "hidden");
			$("hw-health-overheating-led").className = (freq_capped ? (flags.freq_capped.now ? "led-red" : "led-yellow") : "hidden");
			tools.hidden.setVisible($("hw-health-message-undervoltage"), undervoltage);
			tools.hidden.setVisible($("hw-health-message-overheating"), freq_capped);
		}
		__info_health_state = state;
		__renderAboutInfoHardware();
	};

	var __setInfoStateFan = function(state) {
		let failed = false;
		let failed_past = false;
		if (state.monitored) {
			if (state.state === null) {
				failed = true;
			} else {
				if (!state.state.fan.ok) {
					failed = true;
				} else if (state.state.fan.last_fail_ts >= 0) {
					failed = true;
					failed_past = true;
				}
			}
		}
		tools.hidden.setVisible($("fan-health-dropdown"), failed);
		$("fan-health-led").className = (failed ? (failed_past ? "led-yellow" : "led-red") : "hidden");

		__info_fan_state = state;
		__renderAboutInfoHardware();
	};

	var __renderAboutInfoHardware = function() {
		let parts = [];
		if (__info_health_state !== null) {
			parts = [
				"Resources:" + __formatMisc(__info_health_state),
				"Temperature:" + __formatTemp(__info_health_state.temp),
				"Throttling:" + __formatThrottling(__info_health_state.throttling),
			];
		}
		if (__info_fan_state !== null) {
			parts.push("Fan:" + __formatFan(__info_fan_state));
		}
		$("about-hardware").innerHTML = parts.join("<hr>");
	};

	var __formatMisc = function(state) {
		return __formatUl([
			["CPU", `${state.cpu.percent}%`],
			["MEM", `${state.mem.percent}%`],
		]);
	};

	var __formatFan = function(state) {
		if (!state.monitored) {
			return __formatUl([["Status", "Not monitored"]]);
		} else if (state.state === null) {
			return __formatUl([["Status", __red("Not available")]]);
		} else {
			state = state.state;
			let pairs = [
				["Status", (state.fan.ok ? __green("Ok") : __red("Failed"))],
				["Desired speed", `${state.fan.speed}%`],
				["PWM", `${state.fan.pwm}`],
			];
			if (state.hall.available) {
				pairs.push(["RPM", __colored(state.fan.ok, state.hall.rpm)]);
			}
			return __formatUl(pairs);
		}
	};

	var __formatTemp = function(temp) {
		let pairs = [];
		for (let field of Object.keys(temp).sort()) {
			pairs.push([field.toUpperCase(), `${temp[field]}&deg;C`]);
		}
		return __formatUl(pairs);
	};

	var __formatThrottling = function(throttling) {
		if (throttling !== null) {
			let pairs = [];
			for (let field of Object.keys(throttling.parsed_flags).sort()) {
				let flags = throttling.parsed_flags[field];
				let key = tools.upperFirst(field).replace("_", " ");
				let value = (flags["now"] ? __red("RIGHT NOW") : __green("No"));
				if (!throttling.ignore_past) {
					value += "; " + (flags["past"] ? __red("In the past") : __green("Never"));
				}
				pairs.push([key, value]);
			}
			return __formatUl(pairs);
		} else {
			return "NO DATA";
		}
	};

	var __setInfoStateSystem = function(state) {
		$("about-version").innerHTML = `
			Base: ${__commented(state.platform.base)}<br>
			Serial: ${__commented(state.platform.serial)}<br>
			<hr>
			KVMD: ${__commented(state.kvmd.version)}<br>
			<hr>
			Streamer: ${__commented(state.streamer.version + " (" + state.streamer.app + ")")}<br>
			${__formatStreamerFeatures(state.streamer.features)}<br>
			<hr>
			${state.kernel.system} kernel:<br>
			${__formatUname(state.kernel)}
		`;
		$("kvmd-version-kvmd").innerText = state.kvmd.version;
		$("kvmd-version-streamer").innerText = state.streamer.version;
	};

	var __formatStreamerFeatures = function(features) {
		let pairs = [];
		for (let field of Object.keys(features).sort()) {
			pairs.push([field, (features[field] ? "Yes" : "No")]);
		}
		return __formatUl(pairs);
	};

	var __formatUname = function(kernel) {
		let pairs = [];
		for (let field of Object.keys(kernel).sort()) {
			if (field !== "system") {
				pairs.push([tools.upperFirst(field), kernel[field]]);
			}
		}
		return __formatUl(pairs);
	};

	var __formatUl = function(pairs) {
		let html = "";
		for (let pair of pairs) {
			html += `<li>${pair[0]}: ${__commented(pair[1])}</li>`;
		}
		return `<ul>${html}</ul>`;
	};

	var __green = (html) => __colored(true, html);
	var __red = (html) => __colored(false, html);
	var __colored = (ok, html) => `<font color="${ok ? "green" : "red"}">${html}</font>`;
	var __commented = (html) => `<span class="code-comment">${html}</span>`;

	var __setInfoStateExtras = function(state) {
		let show_hook = null;
		let close_hook = null;
		let has_webterm = (state.webterm && (state.webterm.enabled || state.webterm.started));
		if (has_webterm) {
			let loc = window.location;
			let base = `${loc.protocol}//${loc.host}${loc.pathname}${ROOT_PREFIX}`;
			// Tailing slash after state.webterm.path is added to avoid Nginx 301 redirect
			// when the location doesn't have tailing slash: "foo -> foo/".
			// Reverse proxy over PiKVM can be misconfigured to handle this.
			let url = base + state.webterm.path + "/?disableLeaveAlert=true";
			show_hook = function() {
				tools.info("Terminal opened: ", url);
				$("webterm-iframe").src = url;
			};
			close_hook = function() {
				tools.info("Terminal closed");
				$("webterm-iframe").src = "";
			};
		}
		tools.feature.setEnabled($("system-tool-webterm"), has_webterm);
		$("webterm-window").show_hook = show_hook;
		$("webterm-window").close_hook = close_hook;
	};

	var __startSession = function() {
		$("link-led").className = "led-yellow";
		$("link-led").title = "Connecting...";

		tools.httpGet("api/auth/check", null, function(http) {
			if (http.status === 200) {
				__ws = new WebSocket(tools.makeWsUrl("api/ws"));
				__ws.sendHidEvent = (event) => __sendHidEvent(__ws, event.event_type, event.event);
				__ws.binaryType = "arraybuffer";
				__ws.onopen = __wsOpenHandler;
				__ws.onmessage = async (event) => {
					if (typeof event.data === "string") {
						event = JSON.parse(event.data);
						__wsJsonHandler(event.event_type, event.event);
					} else { // Binary
						__wsBinHandler(event.data);
					}
				};
				__ws.onerror = __wsErrorHandler;
				__ws.onclose = __wsCloseHandler;
			} else if (http.status === 401 || http.status === 403) {
				window.onbeforeunload = () => null;
				wm.error("Unexpected logout occured, please login again").then(function() {
					tools.currentOpen("login");
				});
			} else {
				__wsCloseHandler(null);
			}
		});
	};

	var __ascii_encoder = new TextEncoder("ascii");

	var __sendHidEvent = function(ws, event_type, event) {
		if (event_type === "key") {
			let data = __ascii_encoder.encode("\x01\x00" + event.key);
			data[1] = (event.state ? 1 : 0);
			if (event.finish === true) { // Optional
				data[1] |= 0x02;
			}
			ws.send(data);

		} else if (event_type === "mouse_button") {
			let data = __ascii_encoder.encode("\x02\x00" + event.button);
			data[1] = (event.state ? 1 : 0);
			ws.send(data);

		} else if (event_type === "mouse_move") {
			let data = new Uint8Array([
				3,
				(event.to.x >> 8) & 0xFF, event.to.x & 0xFF,
				(event.to.y >> 8) & 0xFF, event.to.y & 0xFF,
			]);
			ws.send(data);

		} else if (event_type === "mouse_relative" || event_type === "mouse_wheel") {
			let data;
			if (Array.isArray(event.delta)) {
				data = new Int8Array(2 + event.delta.length * 2);
				let index = 0;
				for (let delta of event.delta) {
					data[index + 2] = delta["x"];
					data[index + 3] = delta["y"];
					index += 2;
				}
			} else {
				data = new Int8Array([0, 0, event.delta.x, event.delta.y]);
			}
			data[0] = (event_type === "mouse_relative" ? 4 : 5);
			data[1] = (event.squash ? 1 : 0);
			ws.send(data);
		}
	};

	var __wsOpenHandler = function(event) {
		tools.debug("Session: socket opened:", event);
		$("link-led").className = "led-green";
		$("link-led").title = "Connected";
		__recorder.setSocket(__ws);
		__hid.setSocket(__ws);
		__missed_heartbeats = 0;
		__ping_timer = setInterval(__pingServer, 1000);
	};

	var __wsBinHandler = function(data) {
		data = new Uint8Array(data);
		if (data[0] === 255) { // Pong
			__missed_heartbeats = 0;
		}
	};

	var __wsJsonHandler = function(event_type, event) {
		switch (event_type) {
			case "info": __setInfoState(event); break;
			case "gpio": __gpio.setState(event); break;
			case "hid": __hid.setState(event); break;
			case "hid_keymaps": __paste.setState(event); break;
			case "atx": __atx.setState(event); break;
			case "streamer": __streamer.setState(event); break;
			case "ocr": __ocr.setState(event); break;

			case "msd":
				if (event.online === false) {
					__switch.setMsdConnected(false);
				} else if (event.drive !== undefined) {
					__switch.setMsdConnected(event.drive.connected);
				}
				__msd.setState(event);
				break;

			case "switch":
				if (event.model) {
					__atx.setHasSwitch(event.model.ports.length > 0);
				}
				__switch.setState(event);
				break;
		}
	};

	var __wsErrorHandler = function(event) {
		tools.error("Session: socket error:", event);
		if (__ws) {
			__ws.onclose = null;
			__ws.close();
			__wsCloseHandler(null);
		}
	};

	var __wsCloseHandler = function(event) {
		tools.debug("Session: socket closed:", event);

		$("link-led").className = "led-gray";

		if (__ping_timer) {
			clearInterval(__ping_timer);
			__ping_timer = null;
		}

		__gpio.setState(null);
		__hid.setSocket(null); // auto setState(null);
		__paste.setState(null);
		__atx.setState(null);
		__msd.setState(null);
		__streamer.setState(null);
		__ocr.setState(null);
		__recorder.setSocket(null);
		__switch.setState(null);
		__ws = null;

		setTimeout(function() {
			$("link-led").className = "led-yellow";
			setTimeout(__startSession, 500);
		}, 500);
	};

	var __pingServer = function() {
		try {
			__missed_heartbeats += 1;
			if (__missed_heartbeats >= 15) {
				throw new Error("Too many missed heartbeats");
			}
			__ws.send(new Uint8Array([0]));
		} catch (ex) {
			__wsErrorHandler(ex.message);
		}
	};

	__init__();
}