const { z } = require("zod")

const LIMITS = {
    MAX_LINE_LENGTH: 512,
    MAX_MAIL_SIZE: 10 * 1024 * 1024,
    TIMEOUT_MS: 30000
}

function validateEmail(email) {
    const schema = z.string().email().max(255)
    const result = schema.safeParse(email)
    return result.success
}

function isLineSafe(line) {
    if (!line || line.length > LIMITS.MAX_LINE_LENGTH) {
        return false
    }
    
    const dangerousPattern = /[\0\b\v\f]/
    return !dangerousPattern.test(line)
}

function sanitizePath(input) {
    return input.replace(/[^a-zA-Z0-9_\-]/g, "")
}

function createSizeChecker(maxSize = LIMITS.MAX_MAIL_SIZE) {
    let currentSize = 0
    return function(chunkLength) {
        currentSize += chunkLength
        if (currentSize > maxSize) {
            return false
        }
        return true
    }
}

module.exports = {
    isLineSafe,
    sanitizePath,
    validateEmail,
    createSizeChecker
}