[NEST Users] Iaf - psc - delta neurons data

Dear developers/users of nest, I am using the iaf-psc-delta neurons in my network and I need to access the information on the amount of excitatory and inhibitory input that each neuron is receiving in time in order to study balance.(so not just I-e but also the inputs that it is getting from other neurons in the randomly connected network). Can you please help me with this? It would also help if I knew where to find the indices of all the neurons that are presynaptic to a given neuron (a connectivity matrix). I would then be able to calculate the input current myself. Looking forward to hearing from you! Kind regards, Parva