import { MainRouter } from "./routers/main-router";
import * as fs from "node:fs";
import { PackageJson } from "type-fest";
import { Database } from "./database";
import packageJSON from "../package.json";
import { log } from "./log";
import * as socketIO from "socket.io";
import express, { Express } from "express";
import { parse } from "ts-command-line-args";
import https from "https";
import http from "http";
import { Router } from "./router";
import { Socket } from "socket.io";
import { MainSocketHandler } from "./socket-handlers/main-socket-handler";
import { SocketHandler } from "./socket-handler";
import { Settings } from "./settings";
import checkVersion from "./check-version";
import dayjs from "dayjs";
import { R } from "redbean-node";
import { genSecret, isDev } from "./util-common";
import { generatePasswordHash } from "./password-hash";
import { Bean } from "redbean-node/dist/bean";
import { Arguments, Config, DockgeSocket } from "./util-server";
import { DockerSocketHandler } from "./socket-handlers/docker-socket-handler";
import expressStaticGzip from "express-static-gzip";
import path from "path";
import { TerminalSocketHandler } from "./socket-handlers/terminal-socket-handler";
import { Stack } from "./stack";
import { Cron } from "croner";
import gracefulShutdown from "http-graceful-shutdown";
import User from "./models/user";
import childProcess from "child_process";

export class DockgeServer {
    app : Express;
    httpServer : http.Server;
    packageJSON : PackageJson;
    io : socketIO.Server;
    config : Config;
    indexHTML : string = "";

    /**
     * List of express routers
     */
    routerList : Router[] = [
        new MainRouter(),
    ];

    /**
     * List of socket handlers
     */
    socketHandlerList : SocketHandler[] = [
        new MainSocketHandler(),
        new DockerSocketHandler(),
        new TerminalSocketHandler(),
    ];

    /**
     * Show Setup Page
     */
    needSetup = false;

    jwtSecret? : string;

    stacksDir : string = "";

    /**
     *
     */
    constructor() {
        // Catch unexpected errors here
        let unexpectedErrorHandler = (error : unknown) => {
            console.trace(error);
            console.error("If you keep encountering errors, please report to https://github.com/louislam/dockge");
        };
        process.addListener("unhandledRejection", unexpectedErrorHandler);
        process.addListener("uncaughtException", unexpectedErrorHandler);

        if (!process.env.NODE_ENV) {
            process.env.NODE_ENV = "production";
        }

        // Log NODE ENV
        log.info("server", "NODE_ENV: " + process.env.NODE_ENV);

        // Default stacks directory
        let defaultStacksDir;
        if (process.platform === "win32") {
            defaultStacksDir = "./stacks";
        } else {
            defaultStacksDir = "/opt/stacks";
        }

        // Define all possible arguments
        let args = parse<Arguments>({
            sslKey: {
                type: String,
                optional: true,
            },
            sslCert: {
                type: String,
                optional: true,
            },
            sslKeyPassphrase: {
                type: String,
                optional: true,
            },
            port: {
                type: Number,
                optional: true,
            },
            hostname: {
                type: String,
                optional: true,
            },
            dataDir: {
                type: String,
                optional: true,
            },
            stacksDir: {
                type: String,
                optional: true,
            }
        });

        this.config = args as Config;

        // Load from environment variables or default values if args are not set
        this.config.sslKey = args.sslKey || process.env.DOCKGE_SSL_KEY || undefined;
        this.config.sslCert = args.sslCert || process.env.DOCKGE_SSL_CERT || undefined;
        this.config.sslKeyPassphrase = args.sslKeyPassphrase || process.env.DOCKGE_SSL_KEY_PASSPHRASE || undefined;
        this.config.port = args.port || parseInt(process.env.DOCKGE_PORT) || 5001;
        this.config.hostname = args.hostname || process.env.DOCKGE_HOSTNAME || undefined;
        this.config.dataDir = args.dataDir || process.env.DOCKGE_DATA_DIR || "./data/";
        this.config.stacksDir = args.stacksDir || process.env.DOCKGE_STACKS_DIR || defaultStacksDir;
        this.stacksDir = this.config.stacksDir;

        log.debug("server", this.config);

        this.packageJSON = packageJSON as PackageJson;

        try {
            this.indexHTML = fs.readFileSync("./frontend-dist/index.html").toString();
        } catch (e) {
            // "dist/index.html" is not necessary for development
            if (process.env.NODE_ENV !== "development") {
                log.error("server", "Error: Cannot find 'frontend-dist/index.html', did you install correctly?");
                process.exit(1);
            }
        }

        // Create all the necessary directories
        this.initDataDir();

        // Create express
        this.app = express();

        // Create HTTP server
        if (this.config.sslKey && this.config.sslCert) {
            log.info("server", "Server Type: HTTPS");
            this.httpServer = https.createServer({
                key: fs.readFileSync(this.config.sslKey),
                cert: fs.readFileSync(this.config.sslCert),
                passphrase: this.config.sslKeyPassphrase,
            }, this.app);
        } else {
            log.info("server", "Server Type: HTTP");
            this.httpServer = http.createServer(this.app);
        }

        // Binding Routers
        for (const router of this.routerList) {
            this.app.use(router.create(this.app, this));
        }

        // Static files
        this.app.use("/", expressStaticGzip("frontend-dist", {
            enableBrotli: true,
        }));

        // Universal Route Handler, must be at the end of all express routes.
        this.app.get("*", async (_request, response) => {
            response.send(this.indexHTML);
        });

        // Allow all CORS origins in development
        let cors = undefined;
        if (isDev) {
            cors = {
                origin: "*",
            };
        }

        // Create Socket.io
        this.io = new socketIO.Server(this.httpServer, {
            cors,
        });

        this.io.on("connection", async (socket: Socket) => {
            log.info("server", "Socket connected!");

            this.sendInfo(socket, true);

            if (this.needSetup) {
                log.info("server", "Redirect to setup page");
                socket.emit("setup");
            }

            // Create socket handlers
            for (const socketHandler of this.socketHandlerList) {
                socketHandler.create(socket as DockgeSocket, this);
            }

            // ***************************
            // Better do anything after added all socket handlers here
            // ***************************

            log.debug("auth", "check auto login");
            if (await Settings.get("disableAuth")) {
                log.info("auth", "Disabled Auth: auto login to admin");
                this.afterLogin(socket as DockgeSocket, await R.findOne("user"));
                socket.emit("autoLogin");
            } else {
                log.debug("auth", "need auth");
            }

        });

        this.io.on("disconnect", () => {

        });

    }

    async afterLogin(socket : DockgeSocket, user : User) {
        socket.userID = user.id;
        socket.join(user.id.toString());

        this.sendInfo(socket);

        try {
            this.sendStackList();
        } catch (e) {
            log.error("server", e);
        }
    }

    /**
     *
     */
    async serve() {
        // Connect to database
        try {
            await Database.init(this);
        } catch (e) {
            log.error("server", "Failed to prepare your database: " + e.message);
            process.exit(1);
        }

        // First time setup if needed
        let jwtSecretBean = await R.findOne("setting", " `key` = ? ", [
            "jwtSecret",
        ]);

        if (! jwtSecretBean) {
            log.info("server", "JWT secret is not found, generate one.");
            jwtSecretBean = await this.initJWTSecret();
            log.info("server", "Stored JWT secret into database");
        } else {
            log.debug("server", "Load JWT secret from database.");
        }

        this.jwtSecret = jwtSecretBean.value;

        const userCount = (await R.knex("user").count("id as count").first()).count;

        log.debug("server", "User count: " + userCount);

        // If there is no record in user table, it is a new Dockge instance, need to setup
        if (userCount == 0) {
            log.info("server", "No user, need setup");
            this.needSetup = true;
        }

        // Listen
        this.httpServer.listen(5001, this.config.hostname, () => {
            if (this.config.hostname) {
                log.info( "server", `Listening on ${this.config.hostname}:${this.config.port}`);
            } else {
                log.info("server", `Listening on ${this.config.port}`);
            }

            // Run every 5 seconds
            const job = Cron("*/2 * * * * *", {
                protect: true,  // Enabled over-run protection.
            }, () => {
                log.debug("server", "Cron job running");
                this.sendStackList(true);
            });

        });

        gracefulShutdown(this.httpServer, {
            signals: "SIGINT SIGTERM",
            timeout: 30000,                   // timeout: 30 secs
            development: false,               // not in dev mode
            forceExit: true,                  // triggers process.exit() at the end of shutdown process
            onShutdown: this.shutdownFunction,     // shutdown function (async) - e.g. for cleanup DB, ...
            finally: this.finalFunction,            // finally function (sync) - e.g. for logging
        });

    }

    /**
     * Emits the version information to the client.
     * @param socket Socket.io socket instance
     * @param hideVersion Should we hide the version information in the response?
     * @returns
     */
    async sendInfo(socket : Socket, hideVersion = false) {
        let versionProperty;
        let latestVersionProperty;
        let isContainer;

        if (!hideVersion) {
            versionProperty = packageJSON.version;
            latestVersionProperty = checkVersion.latestVersion;
            isContainer = (process.env.DOCKGE_IS_CONTAINER === "1");
        }

        socket.emit("info", {
            version: versionProperty,
            latestVersion: latestVersionProperty,
            isContainer,
            primaryHostname: await Settings.get("primaryHostname"),
            //serverTimezone: await this.getTimezone(),
            //serverTimezoneOffset: this.getTimezoneOffset(),
        });
    }

    /**
     * Get the IP of the client connected to the socket
     * @param {Socket} socket Socket to query
     * @returns IP of client
     */
    async getClientIP(socket : Socket) : Promise<string> {
        let clientIP = socket.client.conn.remoteAddress;

        if (clientIP === undefined) {
            clientIP = "";
        }

        if (await Settings.get("trustProxy")) {
            const forwardedFor = socket.client.conn.request.headers["x-forwarded-for"];

            if (typeof forwardedFor === "string") {
                return forwardedFor.split(",")[0].trim();
            } else if (typeof socket.client.conn.request.headers["x-real-ip"] === "string") {
                return socket.client.conn.request.headers["x-real-ip"];
            }
        }
        return clientIP.replace(/^::ffff:/, "");
    }

    /**
     * Attempt to get the current server timezone
     * If this fails, fall back to environment variables and then make a
     * guess.
     * @returns {Promise<string>} Current timezone
     */
    async getTimezone() {
        // From process.env.TZ
        try {
            if (process.env.TZ) {
                this.checkTimezone(process.env.TZ);
                return process.env.TZ;
            }
        } catch (e) {
            log.warn("timezone", e.message + " in process.env.TZ");
        }

        const timezone = await Settings.get("serverTimezone");

        // From Settings
        try {
            log.debug("timezone", "Using timezone from settings: " + timezone);
            if (timezone) {
                this.checkTimezone(timezone);
                return timezone;
            }
        } catch (e) {
            log.warn("timezone", e.message + " in settings");
        }

        // Guess
        try {
            const guess = dayjs.tz.guess();
            log.debug("timezone", "Guessing timezone: " + guess);
            if (guess) {
                this.checkTimezone(guess);
                return guess;
            } else {
                return "UTC";
            }
        } catch (e) {
            // Guess failed, fall back to UTC
            log.debug("timezone", "Guessed an invalid timezone. Use UTC as fallback");
            return "UTC";
        }
    }

    /**
     * Get the current offset
     * @returns {string} Time offset
     */
    getTimezoneOffset() {
        return dayjs().format("Z");
    }

    /**
     * Throw an error if the timezone is invalid
     * @param {string} timezone Timezone to test
     * @returns {void}
     * @throws The timezone is invalid
     */
    checkTimezone(timezone : string) {
        try {
            dayjs.utc("2013-11-18 11:55").tz(timezone).format();
        } catch (e) {
            throw new Error("Invalid timezone:" + timezone);
        }
    }

    /**
     * Initialize the data directory
     */
    initDataDir() {
        if (! fs.existsSync(this.config.dataDir)) {
            fs.mkdirSync(this.config.dataDir, { recursive: true });
        }

        // Check if a directory
        if (!fs.lstatSync(this.config.dataDir).isDirectory()) {
            throw new Error(`Fatal error: ${this.config.dataDir} is not a directory`);
        }

        // Create data/stacks directory
        if (!fs.existsSync(this.stacksDir)) {
            fs.mkdirSync(this.stacksDir, { recursive: true });
        }

        log.info("server", `Data Dir: ${this.config.dataDir}`);
    }

    /**
     * Init or reset JWT secret
     * @returns  JWT secret
     */
    async initJWTSecret() : Promise<Bean> {
        let jwtSecretBean = await R.findOne("setting", " `key` = ? ", [
            "jwtSecret",
        ]);

        if (!jwtSecretBean) {
            jwtSecretBean = R.dispense("setting");
            jwtSecretBean.key = "jwtSecret";
        }

        jwtSecretBean.value = generatePasswordHash(genSecret());
        await R.store(jwtSecretBean);
        return jwtSecretBean;
    }

    sendStackList(useCache = false) {
        let roomList = this.io.sockets.adapter.rooms.keys();
        let map : Map<string, object> | undefined;

        for (let room of roomList) {
            // Check if the room is a number (user id)
            if (Number(room)) {

                // Get the list only if there is a room
                if (!map) {
                    map = new Map();
                    let stackList = Stack.getStackList(this, useCache);

                    for (let [ stackName, stack ] of stackList) {
                        map.set(stackName, stack.toSimpleJSON());
                    }
                }

                log.debug("server", "Send stack list to room " + room);
                this.io.to(room).emit("stackList", {
                    ok: true,
                    stackList: Object.fromEntries(map),
                });
            }
        }
    }

    sendStackStatusList() {
        let statusList = Stack.getStatusList();

        let roomList = this.io.sockets.adapter.rooms.keys();

        for (let room of roomList) {
            // Check if the room is a number (user id)
            if (Number(room)) {
                log.debug("server", "Send stack status list to room " + room);
                this.io.to(room).emit("stackStatusList", {
                    ok: true,
                    stackStatusList: Object.fromEntries(statusList),
                });
            } else {
                log.debug("server", "Skip sending stack status list to room " + room);
            }
        }
    }

    getDockerNetworkList() : string[] {
        let res = childProcess.spawnSync("docker", [ "network", "ls", "--format", "{{.Name}}" ]);
        let list = res.stdout.toString().split("\n");

        // Remove empty string item
        list = list.filter((item) => {
            return item !== "";
        }).sort((a, b) => {
            return a.localeCompare(b);
        });

        return list;
    }

    get stackDirFullPath() {
        return path.resolve(this.stacksDir);
    }

    /**
     * Shutdown the application
     * Stops all monitors and closes the database connection.
     * @param signal The signal that triggered this function to be called.
     */
    async shutdownFunction(signal : string | undefined) {
        log.info("server", "Shutdown requested");
        log.info("server", "Called signal: " + signal);

        // TODO: Close all terminals?

        await Database.close();
        Settings.stopCacheCleaner();
    }

    /**
     * Final function called before application exits
     */
    finalFunction() {
        log.info("server", "Graceful shutdown successful!");
    }
}