const {
    LoggingDebugSession,
    InitializedEvent,
    TerminatedEvent,
    OutputEvent,
    StoppedEvent,
    ThreadEvent,
    Thread,
    Scope,
    Variable
    } = require('vscode-debugadapter');

const { spawn } = require('child_process');

class MyLuaDebugSession extends LoggingDebugSession {

constructor() {
        super();

        // Redirigir console.log a la Debug Console
        console.log = (...args) => { this.sendEvent(new OutputEvent(args.join(" ") + "\n")); };
        console.log("Debug Adapter iniciado");
        this._stackFrames = [];
        this.setDebuggerLinesStartAt1(true);
        this.setDebuggerColumnsStartAt1(true);
        this._pendingLocals = null;
        this._pendingUpvalues = null;
        this._pendingGlobals = null;
        this._refTable = new Map();   // ref → { luaRef }
        this._nextRef = 1000;         // IDs únicos para tablas
    }

    //initializeRequest(response, args) {
    //    this.sendEvent(new InitializedEvent());
//
    //    response.body = {
    //        supportsConfigurationDoneRequest: true
    //    };
//
    //    this.sendResponse(response);
    //}

    initializeRequest(response, args) {
        console.log("[ADAPTER] initializeRequest");
        this.sendEvent(new InitializedEvent());

        response.body = {
            supportsConfigurationDoneRequest: true,
            supportsEvaluateForHovers: true,
            supportsStepBack: false,
            supportsSetVariable: false,
            supportsRestartFrame: false,
            supportsGotoTargetsRequest: false,
            supportsStepInTargetsRequest: false,
            supportsCompletionsRequest: false,
            supportsRestartRequest: false,
            supportsExceptionInfoRequest: false,
            supportsDelayedStackTraceLoading: false,
            supportsLoadedSourcesRequest: false,
            supportsLogPoints: false,
            supportsTerminateRequest: true,
            supportsTerminateDebuggee: true,
            supportsFunctionBreakpoints: false,
            supportsConditionalBreakpoints: false,
            supportsHitConditionalBreakpoints: false,
            supportsConfigurationDoneRequest: true,
            supportsSetExpression: false,
            supportsClipboardContext: false,
            supportsValueFormattingOptions: false,
            supportsExceptionOptions: false,
            supportsExceptionFilterOptions: false,
            supportsSingleThreadExecutionRequests: true
        };

        this.sendResponse(response);
    }

    pendingStackTrace(frames) {
        this._stackFrames = frames;
    }

    handleLine(line) {
        console.log("[ADAPTER] RAW LINE:", JSON.stringify(line));

        if (!line.startsWith("@@DEBUG@@")) {
            console.log("[ADAPTER] Ignorando línea no-debug");
            return;
        }

        const jsonStr = line.substring(9);
        console.log("[ADAPTER] JSON A PARSEAR:", jsonStr);
    
        let json;
        try {
            json = JSON.parse(jsonStr);
        } catch (e) {
            console.log("[ADAPTER] ERROR PARSEANDO JSON:", e.message);
            return;
        }

        console.log("[ADAPTER] JSON OK:", json);
        console.log("[ADAPTER] TYPE:", json.type);

        if (json.type === "luaError") {
            const e = new OutputEvent(json.message + "\n", "stderr");
            e.body.source = { path: json.file };
            e.body.line = json.line;
            this.sendEvent(e);
            return;
        }

        if (json.type === "break") {
            this.currentFile = json.file;
            this.currentLine = json.line;

            this.sendEvent(new StoppedEvent("breakpoint", 1));
            return;
        }
        if (json.type === "step") {
            this.sendEvent(new StoppedEvent("step", 1));
            return;
        }

        if (json.type === "pause") {
            this.sendEvent(new StoppedEvent("pause", 1));
            return;
        }

        if (json.type === "stackTrace") {
            console.log("[ADAPTER] STACKTRACE PAYLOAD:", JSON.stringify(json.payload));
            console.log("[ADAPTER] BEFORE HANDLING STACKTRACE");
            this.pendingStackTrace(json.payload.frames);
            console.log("[ADAPTER] AFTER HANDLING STACKTRACE");
            return;
        }

        if (json.type === "variables") {
            console.log("[ADAPTER] VARIABLES PAYLOAD:", JSON.stringify(json.payload));

            // 1. Convertimos las variables del motor a formato DAP
            const vars = json.payload.variables.map(v => {
                if (v.type === "table" && v.ref > 0) {
                    const id = this._nextRef++;
                    this._refTable.set(id, v.ref);
                    return {
                        name: v.name,
                        value: v.value,
                        type: v.type,
                        variablesReference: id
                    };
                }

                return {
                    name: v.name,
                    value: v.value,
                    type: v.type,
                    variablesReference: 0
                };
            });

            // 2. Seleccionamos el pendingResponse correcto según el kind
            let response = null;

            if (json.payload.kind === "locals") {
                response = this._pendingLocals;
                this._pendingLocals = null;

            } else if (json.payload.kind === "upvalues") {
                response = this._pendingUpvalues;
                this._pendingUpvalues = null;

            } else if (json.payload.kind === "globals") {
                response = this._pendingGlobals;
                this._pendingGlobals = null;

            } else if (json.payload.kind === "expand") {
                response = this._pendingExpand;
                this._pendingExpand = null;

            } else {
                console.log("[ADAPTER] VARIABLES: kind desconocido:", json.payload.kind);
                return;
            }

            if (!response) {
                console.log("[ADAPTER] VARIABLES: no pending response para kind", json.payload.kind);
                return;
            }

            // 3. Enviamos la respuesta a VSCode
            response.body = { variables: vars };
            this.sendResponse(response);
            return;
        }

        // salida normal
        this.sendEvent(new OutputEvent(line + "\n", "stdout"));
    }

    launchRequest(response, args) {
        console.log("[ADAPTER] launchRequest");

        const program = args.program;
        const cwd = args.cwd || process.cwd();

        this.process = spawn(program, [], {
            cwd: cwd,
            stdio: ['pipe', 'pipe', 'pipe']
        });

        this.sendEvent(new ThreadEvent("started", 1));

        this.stdoutBuffer = "";

        this.process.stdout.on('data', data => {
            this.stdoutBuffer += data.toString();

            let idx;
            while ((idx = this.stdoutBuffer.indexOf("\n")) >= 0) {
                const line = this.stdoutBuffer.slice(0, idx).trim();
                this.stdoutBuffer = this.stdoutBuffer.slice(idx + 1);

                this.handleLine(line);
            }
        });

        this.process.stderr.on('data', data => {
            this.sendEvent(new OutputEvent(data.toString(), "stderr"));
        });

        this.process.on('exit', () => {
            this.sendEvent(new TerminatedEvent());
        });

        this.sendResponse(response);
    }

    sendDebugCommand(obj) {
        if (!this.process || !this.process.stdin) return;
        const msg = "@@DEBUGCMD@@" + JSON.stringify(obj) + "\n";
        console.log("ENVIANDO CMD:", msg);
        this.process.stdin.write(msg);
    }

    nextRequest(response, args) {
        this.sendDebugCommand({ cmd: "stepOver" });
        this.sendResponse(response);
    }

    stepInRequest(response, args) {
        this.sendDebugCommand({ cmd: "stepInto" });
        this.sendResponse(response);
    }

    stepOutRequest(response, args) {
        this.sendDebugCommand({ cmd: "stepOut" });
        this.sendResponse(response);
    }

    setBreakPointsRequest(response, args) {
        const path = args.source.path;          // archivo donde se han puesto breakpoints
        const clientBreakpoints = args.breakpoints || [];

        // Extraemos solo las líneas
        const lines = clientBreakpoints.map(bp => bp.line);

        // Guardamos internamente los breakpoints
        if (!this.breakpoints)
            this.breakpoints = {};

        this.breakpoints[path] = lines;

        // Enviamos los breakpoints a tu aplicación por stdin
        const msg = {
            cmd: "setBreakpoints",
            file: path,
            lines: lines
        };

        this.sendDebugCommand(msg);
        //this.process.stdin.write(
        //    "@@DEBUGCMD@@" + JSON.stringify(msg) + "\n"
        //);

        // VSCode necesita una respuesta con los breakpoints "verificados"
        response.body = {
            breakpoints: lines.map(line => ({
                verified: true,
                line: line
            }))
        };

        this.sendResponse(response);
    }

    continueRequest(response, args) {
        const msg = {
            cmd: "continue"
        };

        this.sendDebugCommand(msg);
        //this.process.stdin.write(
        //    "@@DEBUGCMD@@" + JSON.stringify(msg) + "\n"
        //);

        this.sendResponse(response);
    }

    pauseRequest(response, args) {
        this.sendDebugCommand({ cmd: "pause" });
        this.sendResponse(response);
    }

    stackTraceRequest(response, args) {
        // Pedimos al motor el stack trace
        this.sendDebugCommand({ cmd: "stackTrace" });

        // IMPORTANTE: el motor responde async, así que esperamos
        // a que llegue el mensaje @@DEBUG@@ con type=stackTrace

        const check = () => {
            if (this._stackFrames.length > 0) {
                const frames = this._stackFrames;
                this._stackFrames = [];

                response.body = {
                    stackFrames: frames.map((f, i) => ({
                        id: i + 1,
                        name: f.name,
                        source: { path: f.file },
                        line: f.line,
                        column: 1
                    })),
                    totalFrames: frames.length
                };

                this.sendResponse(response);
            } else {
                setTimeout(check, 5);
            }
        };

        check();
    }

    disconnectRequest(response, args) {
        const msg = { cmd: "continue" }; // por si estaba pausado
        this.sendDebugCommand(msg);
        //this.process.stdin.write("@@DEBUGCMD@@" + JSON.stringify(msg) + "\n");

        this.process.kill();
        this.sendResponse(response);
    }

    threadsRequest(response) {
        // VSCode exige al menos un thread
        response.body = {
            threads: [
                new Thread(1, "Main Thread")
            ]
        };
        this.sendResponse(response);
    }

    stackTraceRequest(response, args) {
        console.log("[ADAPTER] stackTraceRequest");

        // Pedimos el stack trace al motor
        this.sendDebugCommand({ cmd: "stackTrace" });

        // Esperamos la respuesta del motor
        const check = () => {
            if (this._stackFrames && this._stackFrames.length > 0) {
                const frames = this._stackFrames;
                this._stackFrames = [];

                response.body = {
                    stackFrames: frames.map((f, i) => ({
                        id: i + 1,
                        name: f.name,
                        source: { path: f.file },
                        line: f.line,
                        column: 1
                    })),
                    totalFrames: frames.length
                };

                this.sendResponse(response);
            } else {
                setTimeout(check, 5);
            }
        };

        check();
    }

    // Aún no tiene en cuenta el frame
    scopesRequest(response, args) {
        console.log("[ADAPTER] scopesRequest, frameId =", args.frameId);

        response.body = {
            scopes: [
                new Scope("Locals", 1, false),
                new Scope("Upvalues", 2, false),
                new Scope("Globals", 3, true)
            ]
        };

        this.sendResponse(response);
    }

    variablesRequest(response, args) {
        console.log("[ADAPTER] variablesRequest ref =", args.variablesReference);

        if (args.variablesReference === 1) {
            this._pendingLocals = response;
            this.sendDebugCommand({ cmd: "locals" });
            return;
        }

        if (args.variablesReference === 2) {
            this._pendingUpvalues = response;
            this.sendDebugCommand({ cmd: "upvalues" });
            return;
        }

        if (args.variablesReference === 3) {
            this._pendingGlobals = response;
            this.sendDebugCommand({ cmd: "globals" });
            return;
        }

        // Expansión de tablas
        if (args.variablesReference >= 1000) {
            const luaRef = this._refTable.get(args.variablesReference);

            if (!luaRef) {
                console.log("[ADAPTER] No existe luaRef para", args.variablesReference);
                response.body = { variables: [] };
                this.sendResponse(response);
                return;
            }

            this._pendingExpand = response;
            this.sendDebugCommand({ cmd: "expand", ref: luaRef });
            return;
        }

        // de momento, resto vacío
        response.body = { variables: [] };
        this.sendResponse(response);
    }

    configurationDoneRequest(response, args) {
        console.log("[ADAPTER] configurationDoneRequest");
        this.sendResponse(response);
    }

}

new MyLuaDebugSession().start(process.stdin, process.stdout);