Feature Request: Conditional Close on chart / at certain price not just at market

Please could you implement the ability to put a conditional close as a line on the charts - just like you can put buy stops, sell stops etc. Or a
conditional close at a certain price not at just at market. Should be simple enough. Just like adding a take profit or a stop loss but for only part of the trade.

So if I bought 1million GBPUSD at 1.6000 and my stop was at 1.5950. If the price moved to 1.6100 and I wanted to guarantee 1/2 million at 1.6080 I
would place a conditional close at 1.6080. therefore if the price dropped 20 pips it would close 1/2 my original position. If the price continued up
it wouldn't. so it's like a stop loss but only a partial stop loss.

If the same trade reached 1.6150 and I wanted to bank 1/2 of my position there then it would close 1/2 of it at 1.6150 and leave the rest on. So that would be like a partial take profit.

The reason I ask for this is that sometimes I close half of my position when It makes a nice amount of profit.... but I would rather have a
conditional close line underneath it (for a long) instead and let the whole of it run for more profit - with the guarantee of a conditional stop for half of it if
it did turn round.

It could also be viewed as being the opposite of merging two trades together - so splitting them and then you could add a different stop loss or take profit to each part.

Currently the conditional close is only at market and if you could choose the figure that if the price went above or below (for stop loss and take profit options)instead that would be of immense help to many i'm sure.

I know there are ways around this - opening multiple positions at the start, opening new positions to close etc but these are awkward and costly. The above simple solution would be greatly appreciated.