const fs = require("fs");
const path = require("path");

function extract(directoryPath) {
    const mail = new RegExp(
        "([a-z0-9_.+-]+)@([a-z0-9.-]+)\\.(([a-zA-Z0-9]|\\.){2,})",
        "g",
    );

    try {
        let emails = [];
        const dirs = fs.readdirSync(directoryPath, { withFileTypes: true });

        for (const dir of dirs) {
            if (dir.isFile()) {
                const data = fs.readFileSync(
                    path.join(directoryPath, dir.name),
                    "utf8",
                );
                const matches = data.match(mail);

                if (matches) {
                    emails = [...emails, ...matches];
                }
            } else if (dir.isDirectory()) {
                emails = [
                    ...emails,
                    ...extract(path.join(directoryPath, dir.name)),
                ];
            }
        }

        return emails;
    } catch {
        throw new Error("The directory does not exist");
    }
}

/*

fzhfeklzjfh@dakljhlzekj.f
fkzjefh@aaa0.fr
dejkzd@djkelh.fr
djhezklf0587dzedez@gmail................
xavier.login@epita.fr
xavier.login@epita.fR

*/

module.exports = {
    extract,
};

console.log(extract("gallery"));