-- Email Client (client.lua)
local modem = peripheral.find("modem")  -- Auto-detect modem
if not modem then
    print("No modem found!")
    return
end
rednet.open("front")  -- Open the modem on the "front" side

-- Function to send email to the server
local function sendEmail()
    print("Enter recipient ID (Server ID should be 'server'):")
    local recipientID = read()
    if recipientID ~= "server" then
        print("Error: Invalid recipient ID")
        return
    end
    print("Enter email subject:")
    local subject = read()
    print("Enter email message:")
    local message = read()

    -- Ensure valid recipient ID, subject, and message
    if recipientID == "" or subject == "" or message == "" then
        print("All fields must be filled out!")
        return
    end

    -- Debugging: Check what is being sent
    print("Sending email to server...")
    print("Recipient ID: " .. recipientID)
    print("Subject: " .. subject)
    print("Message: " .. message)

    -- Send email to server via Rednet
    rednet.send(recipientID, { "sendEmail", os.getComputerID(), subject, message })
    print("Email sent to " .. recipientID)
end

-- Function to retrieve emails from the server
local function retrieveEmails()
    print("Retrieving emails...")
    rednet.send("server", { "retrieveEmails", os.getComputerID() })

    -- Wait for response from server
    while true do
        local senderID, msg = rednet.receive()  -- Receive message from the server
        if msg[1] == "emailContent" then
            print("Emails retrieved:")
            print(msg[2])
            break
        end
    end
end

-- Main menu to either send or retrieve emails
while true do
    print("1. Send Email")
    print("2. Retrieve Emails")
    local choice = tonumber(read())

    if choice == 1 then
        sendEmail()
    elseif choice == 2 then
        retrieveEmails()
    else
        print("Invalid choice")
    end
end