Put the orange and lemon zests and juice, and the sugar in a small saucepan. Simmer over a medium heat for 6-8 minutes until the liquid has reduced by half.
Set aside half the liquid. Mix the rest with the vinegar, then pour over the grated carrot.
Put a saucepan over a medium heat and add enough oil to cover the base of the pan. When you feel a strong heat rising, add the curry leaves and fry for 30 seconds. Remove from the pan and drain on kitchen paper. Roughly chop and put in an airtight container.
Dice the mango and gently mix into the grated carrot. Season and add the chilli, chopped coriander and curry leaves.
Drop the rice paper wrappers, 1 at a time, into a bowl of warm water. Leave for 30 seconds until soft, remove and shake off the water.
Put a small pile of carrot mixture in the middle of each circle. Bring the lower part of the wrapper up over the vegetables, then fold in the sides. Wrap up tightly, slice in half and repeat with the remaining wrappers. Serve the reserved orange juice as a dipping sauce on the side.