// main.js
const { app, BrowserWindow } = require('electron');
const fs = require("fs");
const path = require("path");
const chokidar = require("chokidar");
const axios = require("axios");

let OUT_DIR;   // endgültiger Eingangsordner (wird in app.whenReady gesetzt)
let IMG_DIR;   // Ausgabeordner für latest.png

let win;
function createWindow() {
    win = new BrowserWindow({
        width: 1000,
        height: 800,
        webPreferences: { nodeIntegration: true, contextIsolation: false }
    });
    win.loadFile(path.join(__dirname, "index.html"));
}

app.whenReady().then(() => {
    // Versuche zuerst C:\ZIR_Output (praktisch für Windows Local Port)
    const preferedRoot = "C:\\ZIR_Output";
    let dataDir = app.getPath("userData"); // fallback

    try {
        // Versuch: C:\ZIR_Output anlegen (falls möglich)
        if (!fs.existsSync(preferedRoot)) {
            fs.mkdirSync(preferedRoot, { recursive: true });
        }
        OUT_DIR = preferedRoot;
    } catch (e) {
        // Falls es schiefgeht (Rechte), fallback in userData
        OUT_DIR = path.join(dataDir, "ZIR_Input");
    }

    // IMG_DIR im userData (schützt vor Schreibrechten)
    IMG_DIR = path.join(dataDir, "zpl_out");

    // Ordner anlegen, falls nicht existierend
    try { if (!fs.existsSync(OUT_DIR)) fs.mkdirSync(OUT_DIR, { recursive: true }); } catch(e) {}
    try { if (!fs.existsSync(IMG_DIR)) fs.mkdirSync(IMG_DIR, { recursive: true }); } catch(e) {}

    console.log("ZIR Input (Eingangsordner):", OUT_DIR);
    console.log("ZIR Output (PNG-Ordner):", IMG_DIR);

    createWindow();

    const watcher = chokidar.watch(OUT_DIR, { ignoreInitial: true, awaitWriteFinish: {stabilityThreshold: 500, pollInterval: 100} });
    watcher.on("add", file => {
        if (!file.toLowerCase().endsWith(".zpl")) return;
        processFile(file);
    });
    watcher.on("change", file => {
        if (!file.toLowerCase().endsWith(".zpl")) return;
        processFile(file);
    });

    app.on('activate', () => { if (BrowserWindow.getAllWindows().length === 0) createWindow(); });
});

app.on('window-all-closed', () => { if (process.platform !== 'darwin') app.quit(); });

/* --- Helferfunktionen --- */

function extractZPL(raw) {
    const start = raw.indexOf("^XA");
    const end = raw.lastIndexOf("^XZ");
    if (start >= 0 && end >= 0 && end > start) return raw.slice(start, end + 3);
    if (start >= 0) return raw.slice(start) + (raw.includes("^XZ") ? "" : "^XZ");
    return "^XA\n" + raw + "\n^XZ";
}

function cleanControlChars(s) {
    return s.replace(/[\x00-\x1F]/g, '');
}

function parsePWLL(zpl) {
    const pwMatch = zpl.match(/\^PW\s*?(\d+)/i) || zpl.match(/\^PW(\d+)/i);
    const llMatch = zpl.match(/\^LL\s*?(\d+)/i) || zpl.match(/\^LL(\d+)/i);
    const pw = pwMatch ? parseInt(pwMatch[1], 10) : null;
    const ll = llMatch ? parseInt(llMatch[1], 10) : null;
    return { pw, ll };
}

function parseMaxFO(zpl) {
    let maxX = 0, maxY = 0;
    const re = /\^FO\s*?(\d+)\s*,\s*(\d+)/g;
    let m;
    while ((m = re.exec(zpl)) !== null) {
        const x = parseInt(m[1], 10);
        const y = parseInt(m[2], 10);
        if (!isNaN(x) && x > maxX) maxX = x;
        if (!isNaN(y) && y > maxY) maxY = y;
    }
    return { maxX, maxY };
}

function dotsToInches(dots, dpi) {
    if (!dots || !dpi) return null;
    return dots / dpi;
}

function fmtInches(v) {
    return (Math.round(v * 100) / 100).toString();
}

async function tryLabelaryRender(zpl, printerKey, widthInches, heightInches) {
    const url = `http://api.labelary.com/v1/printers/${printerKey}/labels/${widthInches}x${heightInches}/0/`;
    try {
        const resp = await axios.post(url, zpl, {
            headers: { "Accept": "image/png" },
            responseType: "arraybuffer",
            timeout: 15000
        });
        return { ok: true, buffer: resp.data };
    } catch (err) {
        const status = err.response ? err.response.status : null;
        return { ok: false, status, error: err.message };
    }
}

/* --- Größen & Druckeroptionen --- */

const STANDARD_SIZES = [
    { w: 8.27, h: 11.69, name: "A4" },
    { w: 8.5,  h: 11,    name: "Letter" },
    { w: 4,    h: 6,     name: "4x6" },
    { w: 3,    h: 2,     name: "3x2" },
    { w: 4,    h: 3,     name: "4x3" },
    { w: 2,    h: 6,     name: "2x6" },
    { w: 1,    h: 1,     name: "1x1" }
];

const PRINTER_OPTIONS = [
    { key: "8dpmm", dpi: 203 },
    { key: "12dpmm", dpi: 305 }
];

/* --- Hauptverarbeitung --- */
let busy = false;
async function processFile(filePath) {
    if (busy) {
        setTimeout(() => processFile(filePath), 400);
        return;
    }
    busy = true;

    try {
        console.log("Verarbeite:", filePath);
        let raw = fs.readFileSync(filePath, "utf-8");
        raw = cleanControlChars(raw);
        let zpl = extractZPL(raw);

        const { pw, ll } = parsePWLL(zpl);
        const { maxX, maxY } = parseMaxFO(zpl);
        console.log("Parsed PW/LL:", pw, ll, "maxFO:", maxX, maxY);

        // sizesToTry aufbauen (Priorität: PW/LL -> geschätzte große Formate -> Standardgrößen)
        const sizesToTry = [];

        if (pw && ll) {
            for (const p of PRINTER_OPTIONS) {
                const wIn = dotsToInches(pw, p.dpi);
                const hIn = dotsToInches(ll, p.dpi);
                if (wIn && hIn) {
                    sizesToTry.push({ w: wIn, h: hIn, printer: p });
                    sizesToTry.push({ w: hIn, h: wIn, printer: p, rotated: true });
                }
            }
        }

        const estDefaultDPI = 203;
        const estWIn = maxX ? dotsToInches(maxX + 100, estDefaultDPI) : null; // margin
        const estHIn = maxY ? dotsToInches(maxY + 100, estDefaultDPI) : null;

        if (estWIn && estHIn) {
            if (estWIn > 6 || estHIn > 8 || estWIn > 8 || estHIn > 6) {
                for (const p of PRINTER_OPTIONS) {
                    sizesToTry.push({ w: 8.27, h: 11.69, printer: p, name: "A4" });
                    sizesToTry.push({ w: 11.69, h: 8.27, printer: p, name: "A4_rot" });
                    sizesToTry.push({ w: 8.5, h: 11, printer: p, name: "Letter" });
                    sizesToTry.push({ w: 11, h: 8.5, printer: p, name: "Letter_rot" });
                }
            }
        }

        for (const p of PRINTER_OPTIONS) {
            for (const s of STANDARD_SIZES) {
                const exists = sizesToTry.some(x => Math.abs(x.w - s.w) < 0.01 && Math.abs(x.h - s.h) < 0.01 && x.printer.key === p.key);
                if (!exists) sizesToTry.push({ w: s.w, h: s.h, printer: p, name: s.name || `${s.w}x${s.h}` });
            }
        }

        // Duplikate entfernen & Reihenfolge behalten
        const uniqSizes = [];
        const seen = new Set();
        for (const s of sizesToTry) {
            const key = `${s.printer.key}-${Math.round(s.w*100)}/${Math.round(s.h*100)}`;
            if (!seen.has(key)) { seen.add(key); uniqSizes.push(s); }
        }

        // Versuche rendern
        let renderResult = null;
        for (const s of uniqSizes) {
            const wStr = fmtInches(s.w);
            const hStr = fmtInches(s.h);
            console.log(`Versuche rendern: printer=${s.printer.key} size=${wStr}x${hStr} (${s.name || ""})`);
            renderResult = await tryLabelaryRender(zpl, s.printer.key, wStr, hStr);
            if (renderResult.ok) { console.log(`Erfolg mit ${s.printer.key} ${wStr}x${hStr}`); break; }
            else { console.log(`Fehler (${renderResult.status}) mit ${s.printer.key} ${wStr}x${hStr}`); }
        }

        if (!renderResult || !renderResult.ok) {
            console.error("Alle Render-Versuche fehlgeschlagen, Abbruch.");
            busy = false;
            return;
        }

        // PNG speichern (latest.png) — alte PNGs löschen
        const pngBuffer = renderResult.buffer;
        try {
            fs.readdirSync(IMG_DIR).forEach(f => {
                const fileToDelete = path.join(IMG_DIR, f);
                try { if (fs.lstatSync(fileToDelete).isFile()) fs.unlinkSync(fileToDelete); } catch(e){}
            });
        } catch(e){}

        const outFile = path.join(IMG_DIR, "latest.png");
        fs.writeFileSync(outFile, pngBuffer);
        console.log("PNG erstellt:", outFile);

        // verarbeitete ZPL-Datei löschen (optional)
        try { fs.unlinkSync(filePath); } catch(e){ console.warn("Konnte ZPL nicht löschen:", e.message); }

        // Fenster benachrichtigen
        win.webContents.send("show-png", outFile);

    } catch (err) {
        console.error("Fehler beim Rendern:", err && err.message ? err.message : err);
    } finally {
        busy = false;
    }
}