lib.rs

use avalanche-types::{
    core::{
        codec::{Codec, Decode, Encode},
        Executable, Execution,
    },
    crypto::{KeyPair, PrivateKey, PublicKey},
    zkp::{BulletproofGroth16, Proof},
};
use std::collections::HashMap;

#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct MyTransaction {
    pub sender: PublicKey,
    pub recipient: PublicKey,
    pub amount: u64,
    pub proof: Proof<BulletproofGroth16>,
}

impl Codec for MyTransaction {
    fn encode(&self) -> Vec<u8> {
        let mut encoded = self.sender.encode();
        encoded.extend(self.recipient.encode());
        encoded.extend(self.amount.encode());
        encoded.extend(self.proof.encode());
        encoded
    }

    fn decode(bytes: &[u8]) -> Result<Self, String> {
        let mut cursor = 0;
        let sender = PublicKey::decode(&bytes[cursor..])?;
        cursor += sender.encode().len();
        let recipient = PublicKey::decode(&bytes[cursor..])?;
        cursor += recipient.encode().len();
        let amount = u64::decode(&bytes[cursor..])?;
        cursor += amount.encode().len();
        let proof = Proof::<BulletproofGroth16>::decode(&bytes[cursor..])?;
        Ok(MyTransaction {
            sender,
            recipient,
            amount,
            proof,
        })
    }
}

impl Executable for MyTransaction {
    fn execute(&self, execution: &mut Execution) -> Result<(), String> {
        // Verify the proof before executing the transaction
        if !self.proof.verify() {
            return Err("invalid proof".to_string());
        }
        let sender = execution.get_account(&self.sender)?;
        let recipient = execution.get_account(&self.recipient)?;
        if sender.balance < self.amount {
            return Err("insufficient balance".to_string());
        }
        sender.balance -= self.amount;
        recipient.balance += self.amount;
        Ok(())
    }
}

#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct SmartContractTransaction {
    pub sender: PublicKey,
    pub contract_address: PublicKey,
    pub data: Vec<u8>,
    pub proof: Proof<BulletproofGroth16>,
}

impl Codec for SmartContractTransaction {
    fn encode(&self) -> Vec<u8> {
        let mut encoded = self.sender.encode();
        encoded.extend(self.contract_address.encode());
        encoded.extend(self.data.encode());
        encoded.extend(self.proof.encode());
        encoded
    }

    fn decode(bytes: &[u8]) -> Result<Self, String> {
        let mut cursor = 0;
        let sender = PublicKey::decode(&bytes[cursor..])?;
        cursor += sender.encode().len();
        let contract_address = PublicKey::decode(&bytes[cursor..])?;
        cursor += contract_address.encode().len();
        let data = Vec::<u8>::decode(&bytes[cursor..])?;
        cursor += data.encode().len();
        let proof = Proof::<BulletproofGroth16>::decode(&bytes[cursor..])?;
        Ok(SmartContractTransaction {
            sender,
            contract_address,
            data,
            proof,
        })
    }
}

impl Executable for SmartContractTransaction {
    fn execute(&self, execution: &mut Execution) -> Result<(), String> {
        // Verify the proof before executing the transaction
        if !self.proof.verify() {
            return Err("invalid proof".to_string());
        }
        let contract = execution.get_account(&self.contract_address)?;
        // Execute the smart contract
        let result = contract.execute(&self.data)?;
        Ok(())
    }
}

#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct MultiAssetTransaction {
    pub sender: PublicKey,
    pub recipient: PublicKey,
    pub assets: Vec<AssetTransfer>,
    pub proof: Proof<BulletproofGroth16>,
}

#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct AssetTransfer {
    pub asset_id: Vec<u8>,
    pub amount: u64,
}

impl Codec for AssetTransfer {
    fn encode(&self) -> Vec<u8> {
        let mut encoded = self.asset_id.encode();
        encoded.extend(self.amount.encode());
        encoded
    }

    fn decode(bytes: &[u8]) -> Result<Self, String> {
        let
        impl Codec for MultiAssetTransaction {
            fn encode(&self) -> Vec<u8> {
                let mut encoded = self.sender.encode();
                encoded.extend(self.recipient.encode());
                encoded.extend(self.assets.encode());
                encoded.extend(self.proof.encode());
                encoded
            }
        
            fn decode(bytes: &[u8]) -> Result<Self, String> {
                let mut cursor = 0;
                let sender = PublicKey::decode(&bytes[cursor..])?;
                cursor += sender.encode().len();
                let recipient = PublicKey::decode(&bytes[cursor..])?;
                cursor += recipient.encode().len();
                let assets = Vec::<AssetTransfer>::decode(&bytes[cursor..])?;
                cursor += assets.encode().len();
                let proof = Proof::<BulletproofGroth16>::decode(&bytes[cursor..])?;
                Ok(MultiAssetTransaction {
                    sender,
                    recipient,
                    assets,
                    proof,
                })
            }
        }
        
        impl Executable for MultiAssetTransaction {
            fn execute(&self, execution: &mut Execution) -> Result<(), String> {
                // Verify the proof before executing the transaction
                if !self.proof.verify() {
                    return Err("invalid proof".to_string());
                    let sender = execution.get_account(&self.sender)?;
                    let recipient = execution.get_account(&self.recipient)?;
                    for asset in self.assets.iter() {
                        let asset_balance = sender.get_asset_balance(&asset.asset_id)?;
                        if asset_balance < asset.amount {
                            return Err("insufficient asset balance".to_string());
                        }
                        sender.set_asset_balance(&asset.asset_id, asset_balance - asset.amount)?;
                        recipient.add_asset_balance(&asset.asset_id, asset.amount)?;
                    }
                    Ok(())
                }
            }
            
            struct MyVirtualMachine {
                accounts: HashMap<PublicKey, Account>,
            }
            
            impl MyVirtualMachine {
                fn new() -> Self {
                    MyVirtualMachine {
                        accounts: HashMap::new(),
                    }
                }
            
                fn create_account(&mut self, keypair: KeyPair) -> PublicKey {
                    let pubkey = keypair.public;
                    let account = Account {
                        keypair,
                        balance: 0,
                        assets: HashMap::new(),
                    };
                    self.accounts.insert(pubkey, account);
                    pubkey
                }
            
                fn get_account(&mut self, pubkey: &PublicKey) -> Result<&mut Account, String> {
                    self.accounts
                        .get_mut(pubkey)
                        .ok_or_else(|| "account not found".to_string())
                }
            }
            
            impl Execution for MyVirtualMachine {
                fn get_account(&mut self, pubkey: &PublicKey) -> Result<&mut Account, String> {
                    self.get_account(pubkey)
                }
            }
            
            struct Account {
                keypair: KeyPair,
                balance: u64,
                assets: HashMap<Vec<u8>, u64>,
            }
            
            impl Account {
                fn get_asset_balance(&self, asset_id: &[u8]) -> Result<u64, String> {
                    self.assets
                        .get(asset_id)
                        .copied()
                        .ok_or_else(|| "asset not found".to_string())
                }
            
                fn set_asset_balance(&mut self, asset_id: &[u8], balance: u64) -> Result<(), String> {
                    self.assets.insert(asset_id.to_vec(), balance);
                    Ok(())
                }
            
                fn add_asset_balance(&mut self, asset_id: &[u8], amount: u64) -> Result<(), String> {
                    let balance = self.get_asset_balance(asset_id)?;
                    self.set_asset_balance(asset_id, balance + amount)?;
                    Ok(())
                }
            }
            
            #[derive(Clone, Debug, Default, Eq, PartialEq)]
            struct DecentralizedGovernanceTransaction {
                pub proposer: PublicKey,
                pub proposal: Vec<u8>,
                pub proof: Proof<BulletproofGroth16>,
            }
            
            impl Codec for DecentralizedGovernanceTransaction {
                fn encode(&self) -> Vec<u8> {
                    let mut encoded = self.proposer.encode();
                    encoded.extend(self.proposal.encode());
                    encoded.extend(self.proof.encode());
                    encoded
                }
            
                fn decode(bytes: &[u8]) -> Result<Self, String> {
                    let mut cursor = 0;
                    let proposer = PublicKey::decode(&bytes[cursor..])?;
                    cursor += proposer.encode().len();
                    let proposal = Vec::<u8>::decode(&bytes[cursor..])?;
                    cursor += proposal.encode().len();
                    let proof = Proof::<BulletproofGroth16>::decode(&bytes[cursor..])?;
                    Ok(DecentralizedGovernanceTransaction {
                        proposer,
                        proposal,
                        proof,
                    })
                }
            }
            
            impl Executable for DecentralizedGovernanceTransaction {
                fn execute(&self, execution: &mut Execution) -> Result<(), String> {
                    // Verify the proof before executing the transaction
                    if !self.proof.verify() {
                        return Err("invalid proof".to_string());
                    }
                    // Check if the proposer has the required stake to propose a change
                    let proposer = execution.get_account(&self.proposer)?;
                    if proposer.stake < MIN_STAKE_TO_PROPOSE {
                        return Err("insufficient stake".to_string());
                    }
                    // Add the proposal to the list of pending proposals
                    let mut pending_proposals = execution.get_pending_proposals()?;
                    pending_proposals.push(self.proposal.clone());
                    execution.set_pending_proposals(pending_proposals)?;
                    Ok(())
                }
            }
            
            #