Airdropping - super duper PoC (not even an MVP!!!).

airdrop.rs

#[ink::contract]
mod airdrop {

  #[ink(storage)]
  pub struct Contract {
    participants: Mapping<u64, AccountId>,
    last_added: u64,
    last_ditributed: u64,
    ready_to_distribute: bool,
    aidrop_amount: u64,
  }
      
  impl Contract {
      // TODO: AccessControl
      #[ink(message)]
      pub fn add_participant(&mut self, participant: AccountId) {
        assert!(!self.ready_to_distribute);
        self.participants.insert(last_added + 1, participant);
        self.last_added = last_added + 1;
      }
      
      #[ink(message)
      pub fn start_distribution(&mut self) {
        self.ready_to_distribute = true;
      }
      
      #[ink(message)]
      pub fn distribute(&mut self, batch_size: u64) {
        for n in 0..batch_size {
          let recipient = self.participants(last_distributed + n).unwrap();
          // PSP22 token here should be the one that is being airdropped
          // transfer OR mint - depending on the design
          PSP22Ref::transfer(airdrop_token, recipient, aidrop_amount).unwrap();
        }
        self.last_distributed = self.last_distributed + batch_size;
      }
    }
  }