-- Function to generate a random key of specified length
local function generateKey(length)
    local key = ""
    for i = 1, length do
        key = key .. string.char(math.random(0, 255))
    end
    return key
end

-- XOR encryption/decryption function
local function xorEncryptDecrypt(data, key)
    local result = {}
    for i = 1, #data do
        local keyIndex = (i - 1) % #key + 1
        result[i] = string.char(bit.bxor(string.byte(data, i), string.byte(key, keyIndex)))
    end
    return table.concat(result)
end

-- Function to encrypt or decrypt all files in a directory
local function processFilesInDirectory(directory, key, mode)
    local files = fs.list(directory)
    for _, file in ipairs(files) do
        local filePath = fs.combine(directory, file)
        if not fs.isDir(filePath) then
            -- Read file contents
            local fileHandle = fs.open(filePath, "r")
            local data = fileHandle.readAll()
            fileHandle.close()

            -- Encrypt or decrypt data
            local processedData = xorEncryptDecrypt(data, key)

            -- Write processed data back to the file
            fileHandle = fs.open(filePath, "w")
            fileHandle.write(processedData)
            fileHandle.close()
        end
    end
end

-- Main program
local function main()
    -- Path to the disk
    local diskPath = "/disk"

    print("Would you like to encrypt or decrypt the files? (e/d)")
    local mode = read()

    if mode == "e" then
        -- Encryption mode
        print("Enter the name to save the decryption key as (e.g., decryption_key.txt):")
        local keyFileName = read()

        print("Enter the directory path to save the decryption key:")
        local keyDirectory = read()

        -- Generate a random encryption key
        local key = generateKey(16) -- 16 bytes key

        -- Save the key to a file
        local keyFilePath = fs.combine(keyDirectory, keyFileName)
        local keyFileHandle = fs.open(keyFilePath, "w")
        keyFileHandle.write(key)
        keyFileHandle.close()

        -- Encrypt all files in the disk directory
        processFilesInDirectory(diskPath, key, "encrypt")

        print("Encryption complete. Key saved to " .. keyFilePath)
    elseif mode == "d" then
        -- Decryption mode
        print("Enter the path to the decryption key file:")
        local keyFilePath = read()

        -- Read the decryption key from the file
        local keyFileHandle = fs.open(keyFilePath, "r")
        local key = keyFileHandle.readAll()
        keyFileHandle.close()

        -- Decrypt all files in the disk directory
        processFilesInDirectory(diskPath, key, "decrypt")

        print("Decryption complete.")
    else
        print("Invalid option. Please run the program again and choose 'e' for encrypt or 'd' for decrypt.")
    end
end

-- Run the main program
main()