testPredict

local nScreenWidth, nScreenHeight = term.getSize()

function limitRead( nLength, cReplaceChar )
    term.setCursorBlink( true )

    nLength = nLength or -1 -- -1 is unlimited
    sReturnString = ""

    xPos, yPos = term.getCursorPos()

    while true do
        predictText(sReturnString)
        term.setCursorPos( xPos, yPos )
        if not cReplaceChar then term.write( sReturnString )
        else term.write( string.rep( cReplaceChar, string.len( sReturnString ) ) ) end

        event, char = os.pullEvent()

        if nLength ~= -1 and string.len( sReturnString ) >= nLength then term.setCursorBlink( false ); return sReturnString end -- Length check

        if event == "char" then sReturnString = sReturnString .. char
        elseif event == "key" and char == 28 then term.setCursorBlink( false ); return sReturnString -- Enter
        elseif event == "key" and char == 14 then -- Backspace
            term.setCursorPos( xPos, yPos )
            term.write( string.rep( " ", string.len( sReturnString ) ) )
            sReturnString = string.sub( sReturnString, 1, string.len( sReturnString )-1 )
            term.setCursorPos( xPos, yPos )

            if not cReplaceChar then term.write( sReturnString )
            else term.write( string.rep( cReplaceChar, string.len( sReturnString ) ) ) end
        end

        term.setCursorPos( xPos, yPos )
        term.write( string.rep( " ", string.len( sReturnString ) ) )
        term.setCursorPos( xPos, yPos )
        if not cReplaceChar then term.write( sReturnString )
        else term.write( string.rep( cReplaceChar, string.len( sReturnString ) ) ) end
    end
end

function predictText(sString)
    local tFiles = fs.list("/")

    if sString:len() > 0 then
        local tOptions = {}
        -- Determine the options predicted.
        for index, fileName in ipairs(tFiles) do
            if fileName:sub(1, sString:len()) == sString then
                table.insert(tOptions, fileName)
            end
        end

        -- Clear the space.
        for line = 4, nScreenHeight - 4 do
            term.setCursorPos(1, line)
            term.write(string.rep(" ", nScreenWidth))
        end

        if #tOptions > 0 then
            -- Print the options.
            for line, fileName in ipairs(tOptions) do
                term.setCursorPos(3, line + 3)
                term.write(fileName)
            end
        else
            term.setCursorPos(3, 4)
            term.write("No results found.")
        end
    else
        for line, fileName in ipairs(tFiles) do
            term.setCursorPos(3, line + 3)
            term.write(fileName)
        end
    end
end

function clearScreen()
    term.clear()
    term.setCursorPos(1, 1)
end

clearScreen()
write("> ")
s = limitRead()