// @ts-check

import fs from "fs";
import path from "path";
import { spawn, ChildProcess } from "child_process";
import { WebSocketServer, WebSocket, RawData } from 'ws';
import http from 'http';
import express from 'express';

const LOG_DIR: string = path.resolve(__dirname, "../models/data");
const LOG_FILE: string = path.join(LOG_DIR, "logs.txt");

let processInstance: ChildProcess | null = null;
let isRunning: boolean = false;
let isAwaitingInput: boolean = false;

const INPUT_PROMPT_STRING = "__NEEDS_INPUT__";

interface ApiType {
    clearLogFile: () => void;
    broadcast: (msg: string | Buffer, wss?: WebSocketServer, isError?: boolean, silent?: boolean) => void;
    parseExocoreRun: (filePath: string) => { exportCommands: string[]; runCommand: string | null };
    executeCommand: (
        command: string,
        cwd: string,
        onCloseCallback: (outcome: number | string | Error) => void,
        wss?: WebSocketServer
    ) => ChildProcess | null;
    runCommandsSequentially: (
        commands: string[],
        cwd: string,
        onSequenceDone: (success: boolean) => void,
        wss?: WebSocketServer,
        index?: number
    ) => void;
    start: (wss?: WebSocketServer, args?: string) => void;
    stop: (wss?: WebSocketServer) => void;
    restart: (wss?: WebSocketServer, args?: string) => void;
    status: () => "running" | "stopped";
}

const api: ApiType = {
    clearLogFile(): void {
        if (!fs.existsSync(LOG_DIR)) {
            fs.mkdirSync(LOG_DIR, { recursive: true });
        }
        fs.writeFileSync(LOG_FILE, "");
    },

    broadcast(msg: string | Buffer, wss?: WebSocketServer, isError: boolean = false, silent: boolean = false): void {
        const data = msg.toString();
        if (!fs.existsSync(LOG_DIR)) {
            fs.mkdirSync(LOG_DIR, { recursive: true });
        }
        if (!data.includes(INPUT_PROMPT_STRING)) {
            fs.appendFileSync(LOG_FILE, `${data}`);
        }

        if (!silent && wss && wss.clients) {
            wss.clients.forEach((client: WebSocket) => {
                if (client.readyState === WebSocket.OPEN) {
                    if (data.includes(INPUT_PROMPT_STRING)) {
                        const cleanData = data.replace(INPUT_PROMPT_STRING, "").trim();
                        isAwaitingInput = true;
                        client.send(JSON.stringify({ type: 'INPUT_REQUIRED', payload: cleanData }));
                    } else {
                        client.send(data);
                    }
                }
            });
        }
        if (isError) {
            console.error(`BROADCAST_ERROR_LOG: ${data.trim()}`);
        }
    },

    parseExocoreRun(filePath: string): { exportCommands: string[]; runCommand: string | null } {
        const raw: string = fs.readFileSync(filePath, "utf8");
        const exportMatch: RegExpMatchArray | null = raw.match(/export\s*=\s*{([\s\S]*?)}/);
        const functionMatch: RegExpMatchArray | null = raw.match(/function\s*=\s*{([\s\S]*?)}/);
        const exportCommands: string[] = [];

        if (exportMatch && exportMatch[1]) {
            const lines: string[] = exportMatch[1].split(";");
            for (let line of lines) {
                const matchResult: RegExpMatchArray | null = line.match(/["'](.+?)["']/);
                if (matchResult && typeof matchResult[1] === 'string' && matchResult[1].trim() !== '') {
                    exportCommands.push(matchResult[1]);
                }
            }
        }

        let runCommand: string | null = null;
        if (functionMatch && functionMatch[1]) {
            const runMatch: RegExpMatchArray | null = functionMatch[1].match(/run\s*=\s*["'](.+?)["']/);
            if (runMatch && typeof runMatch[1] === 'string' && runMatch[1].trim() !== '') {
                runCommand = runMatch[1];
            }
        }
        return { exportCommands, runCommand };
    },

    executeCommand(
        command: string,
        cwd: string,
        onCloseCallback: (outcome: number | string | Error) => void,
        wss?: WebSocketServer
    ): ChildProcess | null {
        let proc: ChildProcess | null = null;
        try {
            proc = spawn(command, {
                cwd,
                shell: true,
                env: { ...process.env, FORCE_COLOR: "1", LANG: "en_US.UTF-8" },
            });
        } catch (rawErr: unknown) {
            let errMsg = "Unknown spawn error";
            if (rawErr instanceof Error) errMsg = rawErr.message;
            else if (typeof rawErr === 'string') errMsg = rawErr;
            api.broadcast(`\x1b[31m❌ Spawn error for command "${command}": ${errMsg}\x1b[0m`, wss, true, false);
            if (typeof onCloseCallback === 'function') {
                if (rawErr instanceof Error) onCloseCallback(rawErr);
                else onCloseCallback(new Error(String(rawErr)));
            }
            return null;
        }

        if (proc.stdout) {
            proc.stdout.on("data", (data: Buffer | string) => api.broadcast(data, wss, false, false));
        }
        if (proc.stderr) {
            proc.stderr.on("data", (data: Buffer | string) => api.broadcast(`\x1b[31m${data.toString()}\x1b[0m`, wss, true, false));
        }

        proc.on("close", (code: number | null, signal: NodeJS.Signals | null) => {
            if (typeof onCloseCallback === 'function') {
                if (code === null) onCloseCallback(signal || 'signaled');
                else onCloseCallback(code);
            }
        });

        proc.on("error", (err: Error) => {
            api.broadcast(`\x1b[31m❌ Command execution error for "${command}": ${err.message}\x1b[0m`, wss, true, false);
            if (typeof onCloseCallback === 'function') onCloseCallback(err);
        });
        return proc;
    },

    runCommandsSequentially(
        commands: string[],
        cwd: string,
        onSequenceDone: (success: boolean) => void,
        wss?: WebSocketServer,
        index: number = 0
    ): void {
        if (index >= commands.length) {
            if (typeof onSequenceDone === 'function') onSequenceDone(true);
            return;
        }
        const cmd = commands[index];

        if (typeof cmd !== 'string' || cmd.trim() === "") {
            api.broadcast(`\x1b[31m❌ Invalid or empty setup command at index ${index}.\x1b[0m`, wss, true, false);
            if (typeof onSequenceDone === 'function') onSequenceDone(false);
            return;
        }

        const proc = api.executeCommand(cmd, cwd, (outcome: number | string | Error) => {
            const benignSignal = (typeof outcome === 'string' && (outcome.toUpperCase() === 'SIGTERM' || outcome.toUpperCase() === 'SIGKILL'));
            if (outcome !== 0 && (typeof outcome === 'number' || outcome instanceof Error || (typeof outcome === 'string' && !benignSignal))) {
                const errorMessage = outcome instanceof Error ? outcome.message : String(outcome);
                api.broadcast(`\x1b[31m❌ Setup command "${cmd}" failed: ${errorMessage}\x1b[0m`, wss, true, false);
                if (typeof onSequenceDone === 'function') onSequenceDone(false);
                return;
            }
            api.runCommandsSequentially(commands, cwd, onSequenceDone, wss, index + 1);
        }, wss
        );

        if (!proc) {
            api.broadcast(`\x1b[31m❌ Failed to initiate setup command "${cmd}".\x1b[0m`, wss, true, false);
            if (typeof onSequenceDone === 'function') onSequenceDone(false);
        }
    },

    start(wss?: WebSocketServer, args?: string): void {
        if (isRunning) {
            api.broadcast("\x1b[33m⚠️ Process is already running.\x1b[0m", wss, true, false);
            return;
        }
        api.clearLogFile();
        api.broadcast(`\x1b[36m[SYSTEM] Starting process...\x1b[0m`, wss, false, true);
        isAwaitingInput = false;

        let projectPath: string | undefined;

        try {
            const configJsonPath: string = path.resolve(process.cwd(), 'config.json');
            if (fs.existsSync(configJsonPath)) {
                const configRaw: string = fs.readFileSync(configJsonPath, 'utf-8');
                if (configRaw.trim() !== "") {
                    const configData: any = JSON.parse(configRaw);
                    if (configData && typeof configData.project === 'string' && configData.project.trim() !== "") {
                        const configJsonDir: string = path.dirname(configJsonPath);
                        const resolvedPath: string = path.resolve(configJsonDir, configData.project);
                        if (fs.existsSync(resolvedPath) && fs.statSync(resolvedPath).isDirectory()) {
                            projectPath = resolvedPath;
                        } else {
                            api.broadcast(`\x1b[31m❌ Error: Project path from config.json is invalid: ${resolvedPath}\x1b[0m`, wss, true, false);
                            return;
                        }
                    } else {
                        api.broadcast(`\x1b[31m❌ Error: 'project' key in config.json is missing or invalid.\x1b[0m`, wss, true, false);
                        return;
                    }
                } else {
                    api.broadcast(`\x1b[31m❌ Error: config.json is empty.\x1b[0m`, wss, true, false);
                    return;
                }
            } else {
                api.broadcast(`\x1b[31m❌ Error: Configuration file not found at ${configJsonPath}.\x1b[0m`, wss, true, false);
                return;
            }
        } catch (rawErr: unknown) {
            api.broadcast(`\x1b[31m❌ Error reading or parsing project configuration.\x1b[0m`, wss, true, false);
            return;
        }

        if (typeof projectPath !== 'string') {
            api.broadcast(`\x1b[31m❌ Project path could not be determined.\x1b[0m`, wss, true, false);
            return;
        }

        const currentProjectPath: string = projectPath;
        const exocoreRunPath: string = path.join(currentProjectPath, "exocore.run");

        if (!fs.existsSync(exocoreRunPath)) {
            api.broadcast(`\x1b[31m❌ Missing exocore.run file in ${currentProjectPath}.\x1b[0m`, wss, true, false);
            return;
        }

        const { exportCommands, runCommand } = api.parseExocoreRun(exocoreRunPath);

        if (!runCommand) {
            api.broadcast("\x1b[31m❌ Missing run command in exocore.run.\x1b[0m", wss, true, false);
            return;
        }

        const currentRunCommand: string = args ? `${runCommand} ${args}` : runCommand;

        api.runCommandsSequentially([...exportCommands], currentProjectPath, (setupSuccess: boolean) => {
            if (!setupSuccess) {
                api.broadcast(`\x1b[31m❌ Setup commands failed. Main process will not start.\x1b[0m`, wss, true, false);
                return;
            }

            api.broadcast(`\x1b[36m[SYSTEM] Executing: ${currentRunCommand}\x1b[0m`, wss, false, true);

            let spawnedProc: ChildProcess | null = null;
            try {
                spawnedProc = spawn(currentRunCommand, {
                    cwd: currentProjectPath,
                    shell: true,
                    detached: true,
                    env: { ...process.env, FORCE_COLOR: "1", LANG: "en_US.UTF-8" },
                });
            } catch (rawErr: unknown) {
                api.broadcast(`\x1b[31m❌ Failed to spawn main process.\x1b[0m`, wss, true, false);
                return;
            }

            if (!spawnedProc || typeof spawnedProc.pid !== 'number') {
                api.broadcast(`\x1b[31m❌ Failed to get process handle.\x1b[0m`, wss, true, false);
                return;
            }

            processInstance = spawnedProc;
            isRunning = true;
            api.broadcast(`\x1b[32m[SYSTEM] Process started with PID: ${processInstance.pid}\x1b[0m`, wss, false, true);

            if (processInstance.stdout) {
                processInstance.stdout.on("data", (data: Buffer | string) => api.broadcast(data, wss, false, false));
            }
            if (processInstance.stderr) {
                processInstance.stderr.on("data", (data: Buffer | string) =>
                    api.broadcast(`\x1b[31m${data.toString()}\x1b[0m`, wss, true, false)
                );
            }

            processInstance.on("close", (code: number | null, signal: NodeJS.Signals | null) => {
                isRunning = false;
                processInstance = null;
                isAwaitingInput = false;
                const exitReason = signal ? `signal ${signal}` : `code ${code}`;
                api.broadcast(`\x1b[33m[SYSTEM] Process exited with ${exitReason}. It will not be restarted automatically.\x1b[0m`, wss, false, false);
            });

            processInstance.on("error", (err: Error) => {
                api.broadcast(`\x1b[31m❌ Error with main process: ${err.message}\x1b[0m`, wss, true, false);
                isRunning = false;
                processInstance = null;
                isAwaitingInput = false;
            });
        }, wss);
    },

    stop(wss?: WebSocketServer): void {
        if (!processInstance || typeof processInstance.pid !== 'number') {
            api.broadcast("\x1b[33m⚠️ No active process to stop.\x1b[0m", wss, true, false);
            if (isRunning) {
                isRunning = false;
                processInstance = null;
            }
            return;
        }

        if (!isRunning) {
            api.broadcast("\x1b[33m⚠️ Process is already stopped.\x1b[0m", wss, true, false);
            return;
        }

        const pidToStop: number = processInstance.pid;
        api.broadcast(`\x1b[36m[SYSTEM] Stopping process group PID: ${pidToStop}...\x1b[0m`, wss, false, true);

        try {
            process.kill(-pidToStop, "SIGTERM");

            setTimeout(() => {
                if (processInstance && processInstance.pid === pidToStop && !processInstance.killed) {
                    api.broadcast(`\x1b[33m[SYSTEM] ⚠️ Process ${pidToStop} unresponsive, sending SIGKILL.\x1b[0m`, wss, true, false);
                    try {
                        process.kill(-pidToStop, "SIGKILL");
                    } catch (rawKillErr: unknown) {
                        const err = rawKillErr as NodeJS.ErrnoException;
                        if (err.code !== 'ESRCH') {
                            api.broadcast(`\x1b[31m[SYSTEM] ❌ Error sending SIGKILL to PID ${pidToStop}: ${err.message}\x1b[0m`, wss, true, false);
                        }
                    } finally {
                        if (processInstance && processInstance.pid === pidToStop) {
                            isRunning = false;
                            processInstance = null;
                        }
                    }
                }
            }, 3000);
        } catch (rawTermErr: unknown) {
            const err = rawTermErr as NodeJS.ErrnoException;
            if (err.code !== 'ESRCH') {
                api.broadcast(`\x1b[31m❌ Error sending SIGTERM: ${err.message}\x1b[0m`, wss, true, false);
            }
            isRunning = false;
            processInstance = null;
        }
    },

    restart(wss?: WebSocketServer, args?: string): void {
        api.broadcast(`\x1b[36m[SYSTEM] Restarting process...\x1b[0m`, wss, false, true);
        api.stop(wss);
        setTimeout(() => {
            api.start(wss, args);
        }, 1000);
    },

    status(): "running" | "stopped" {
        if (isRunning && processInstance && !processInstance.killed) {
            try {
                process.kill(processInstance.pid!, 0);
                return "running";
            } catch (e) {
                isRunning = false;
                processInstance = null;
                return "stopped";
            }
        }
        return "stopped";
    },
};

export interface RouteHandlerParamsSuperset {
    app?: express.Application;
    req: express.Request;
    res: express.Response;
    wss?: WebSocketServer;
    wssConsole?: WebSocketServer;
    Shellwss?: WebSocketServer;
    server?: http.Server;
}

export interface ExpressRouteModule {
    method: "get" | "post" | "put" | "delete" | "patch" | "options" | "head" | "all";
    path: string;
    install: (params: Partial<RouteHandlerParamsSuperset>) => void;
}

type StartStopRestartParams = Pick<RouteHandlerParamsSuperset, 'req' | 'res' | 'wssConsole'>;
type ConsoleStatusParams = Pick<RouteHandlerParamsSuperset, 'res'>;

export const modules: Array<{
    method: "get" | "post";
    path: string;
    install: (params: any) => void;
}> = [
    {
        method: "post",
        path: "/start",
        install: ({ req, res, wssConsole }: StartStopRestartParams) => {
            if (!wssConsole) return res.status(500).send("Console WebSocket server not available.");
            api.start(wssConsole, req.body?.args);
            res.send(`Process start initiated.`);
        },
    },
    {
        method: "post",
        path: "/stop",
        install: ({ res, wssConsole }: StartStopRestartParams) => {
            if (!wssConsole) return res.status(500).send("Console WebSocket server not available.");
            api.stop(wssConsole);
            res.send(`Process stop initiated.`);
        },
    },
    {
        method: "post",
        path: "/restart",
        install: ({ req, res, wssConsole }: StartStopRestartParams) => {
            if (!wssConsole) return res.status(500).send("Console WebSocket server not available.");
            api.restart(wssConsole, req.body?.args);
            res.send(`Process restart initiated.`);
        },
    },
    {
        method: "get",
        path: "/console/status",
        install: ({ res }: ConsoleStatusParams) => {
            res.send(api.status());
        },
    },
];

export function setupConsoleWS(wssConsole: WebSocketServer): void {
    wssConsole.on("connection", (ws: WebSocket) => {
        console.log("Console WebSocket client connected");
        try {
            const logContent: string = fs.existsSync(LOG_FILE) ? fs.readFileSync(LOG_FILE, "utf8") : "\x1b[33mℹ️ No previous logs.\x1b[0m";
            ws.send(logContent);
        } catch (err) {
            ws.send("\x1b[31mError reading past logs.\x1b[0m");
        }

        ws.on("message", (rawMessage: RawData) => {
            try {
                const message = JSON.parse(rawMessage.toString());

                if (message.type === 'STDIN_INPUT' && typeof message.payload === 'string') {
                    if (processInstance && isRunning && isAwaitingInput && processInstance.stdin && processInstance.stdin.writable) {
                        processInstance.stdin.write(message.payload + '\n');
                        isAwaitingInput = false;
                    } else {
                        api.broadcast(`\x1b[33m[SYSTEM-WARN] Process not running or not awaiting input.\x1b[0m`, wssConsole, true, false);
                    }
                }
            } catch (e) {
                console.log(`Received non-command message from client: ${rawMessage.toString()}`);
            }
        });

        ws.on("close", () => console.log("Console WebSocket client disconnected"));
        ws.on("error", (error: Error) => console.error("Console WebSocket client error:", error));
    });
}