ESP3D/embedded/config/buildassets.js

let path = require("path");
const fs = require("fs");
const { createReadStream, createWriteStream } = require("fs");
const { createGzip } = require("zlib");
const chalk = require("chalk");

let distPath = path.normalize(__dirname + "/../dist/");
let srcPath = path.normalize(__dirname + "/../assets/");
let headerPath = path.normalize(
    __dirname + "/../../esp3d/src/modules/http/favicon.h"
);

const convertToC = (filepath) => {
    console.log(chalk.yellow("Converting bin to text file"));
    //Cleaning files
    if (fs.existsSync(distPath + "out.tmp")) fs.rmSync(distPath + "out.tmp");
    if (fs.existsSync(distPath + "favicon.h"))
        fs.rmSync(distPath + "favicon.h");

    const data = new Uint8Array(fs.readFileSync(filepath, { flag: "r" }));
    console.log("data size is ", data.length);
    let out = "#define favicon_size  " + data.length + "\n";
    out += "const unsigned char favicon[" + data.length + "] PROGMEM = {\n   ";
    let nb = 0;
    data.forEach((byte, index) => {
        out +=
            " 0x" +
            (byte.toString(16).length == 1 ? "0" : "") +
            byte.toString(16);
        if (index < data.length - 1) out += ",";
        if (nb == 15) {
            out += "\n   ";
            nb = 0;
        } else {
            nb++;
        }
    });

    out += "\n};\n";
    fs.writeFileSync(distPath + "out.tmp", out);

    //Check conversion
    if (fs.existsSync(distPath + "out.tmp")) {
        console.log(chalk.green("[ok]"));
    } else {
        console.log(chalk.red("[error]Conversion failed"));
        return;
    }

    //Format header file
    console.log(chalk.yellow("Building header"));
    fs.writeFileSync(
        distPath + "favicon.h",
        fs.readFileSync(srcPath + "header.txt")
    );
    let bin2cfile = fs.readFileSync(distPath + "out.tmp").toString();
    fs.appendFileSync(distPath + "favicon.h", bin2cfile);
    fs.appendFileSync(
        distPath + "favicon.h",
        fs.readFileSync(srcPath + "footer.txt")
    );

    //Check format result
    if (fs.existsSync(distPath + "favicon.h")) {
        console.log(chalk.green("[ok]"));
    } else {
        console.log(chalk.red("[error]Conversion failed"));
        return;
    }

    //Move file to src
    console.log(chalk.yellow("Overwriting header in sources"));
    fs.writeFileSync(headerPath, fs.readFileSync(distPath + "favicon.h"));
    if (fs.existsSync(headerPath)) {
        console.log(chalk.green("[ok]"));
    } else {
        console.log(chalk.red("[error]Overwriting failed"));
        return;
    }
};

// Create a gzip function for reusable purpose
const compressFile = (filePath, targetPath) => {
    const stream = createReadStream(filePath);
    stream
        .pipe(createGzip(targetPath))
        .pipe(createWriteStream(targetPath))
        .on("finish", () => {
            console.log(`Successfully compressed  at ${targetPath}`);
            convertToC(targetPath);
        });
};

compressFile(srcPath + "favicon.ico", distPath + "favicon.ico.gz");