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mod constants;
mod entry_points;
mod error;
mod runtime_provider;
mod storage_provider;
mod system_provider;
use num_rational::Ratio;
use num_traits::CheckedMul;
use crate::{account::AccountHash, system::CallStackElement, Key, Phase, PublicKey, URef, U512};
pub use crate::system::mint::{
constants::*, entry_points::mint_entry_points, error::Error, runtime_provider::RuntimeProvider,
storage_provider::StorageProvider, system_provider::SystemProvider,
};
pub trait Mint: RuntimeProvider + StorageProvider + SystemProvider {
fn mint(&mut self, initial_balance: U512) -> Result<URef, Error> {
let caller = self.get_caller();
let is_empty_purse = initial_balance.is_zero();
if !is_empty_purse && caller != PublicKey::System.to_account_hash() {
return Err(Error::InvalidNonEmptyPurseCreation);
}
let purse_uref: URef = self.new_uref(())?;
self.write_balance(purse_uref, initial_balance)?;
if !is_empty_purse {
let total_supply_uref = match self.get_key(TOTAL_SUPPLY_KEY) {
None => {
return Err(Error::TotalSupplyNotFound);
}
Some(Key::URef(uref)) => uref,
Some(_) => return Err(Error::MissingKey),
};
self.add(total_supply_uref, initial_balance)?;
}
Ok(purse_uref)
}
fn reduce_total_supply(&mut self, amount: U512) -> Result<(), Error> {
let caller = self.get_caller();
if caller != PublicKey::System.to_account_hash() {
return Err(Error::InvalidTotalSupplyReductionAttempt);
}
if amount.is_zero() {
return Ok(());
}
let total_supply_uref = match self.get_key(TOTAL_SUPPLY_KEY) {
Some(Key::URef(uref)) => uref,
Some(_) => return Err(Error::MissingKey),
None => return Err(Error::MissingKey),
};
let total_supply: U512 = self
.read(total_supply_uref)?
.ok_or(Error::TotalSupplyNotFound)?;
let reduced_total_supply = total_supply
.checked_sub(amount)
.ok_or(Error::ArithmeticOverflow)?;
self.write(total_supply_uref, reduced_total_supply)?;
Ok(())
}
fn balance(&mut self, purse: URef) -> Result<Option<U512>, Error> {
match self.read_balance(purse)? {
some @ Some(_) => Ok(some),
None => Err(Error::PurseNotFound),
}
}
fn transfer(
&mut self,
maybe_to: Option<AccountHash>,
source: URef,
target: URef,
amount: U512,
id: Option<u64>,
) -> Result<(), Error> {
if let (Phase::Session, Some(&CallStackElement::StoredSession { .. })) =
(self.get_phase(), self.get_immediate_caller())
{
return Err(Error::InvalidContext);
}
if !source.is_readable() {
return Err(Error::InvalidAccessRights);
}
if !source.is_writeable() || !target.is_addable() {
return Err(Error::InvalidAccessRights);
}
let source_balance: U512 = match self.read_balance(source)? {
Some(source_balance) => source_balance,
None => return Err(Error::SourceNotFound),
};
if amount > source_balance {
return Err(Error::InsufficientFunds);
}
if self.read_balance(target)?.is_none() {
return Err(Error::DestNotFound);
}
if self.get_main_purse().addr() == source.addr() {
if amount > self.get_approved_spending_limit() {
return Err(Error::UnapprovedSpendingAmount);
}
self.sub_approved_spending_limit(amount);
}
self.write_balance(source, source_balance - amount)?;
self.add_balance(target, amount)?;
self.record_transfer(maybe_to, source, target, amount, id)?;
Ok(())
}
fn read_base_round_reward(&mut self) -> Result<U512, Error> {
let total_supply_uref = match self.get_key(TOTAL_SUPPLY_KEY) {
Some(Key::URef(uref)) => uref,
Some(_) => return Err(Error::MissingKey),
None => return Err(Error::MissingKey),
};
let total_supply: U512 = self
.read(total_supply_uref)?
.ok_or(Error::TotalSupplyNotFound)?;
let round_seigniorage_rate_uref = match self.get_key(ROUND_SEIGNIORAGE_RATE_KEY) {
Some(Key::URef(uref)) => uref,
Some(_) => return Err(Error::MissingKey),
None => return Err(Error::MissingKey),
};
let round_seigniorage_rate: Ratio<U512> = self
.read(round_seigniorage_rate_uref)?
.ok_or(Error::TotalSupplyNotFound)?;
round_seigniorage_rate
.checked_mul(&Ratio::from(total_supply))
.map(|ratio| ratio.to_integer())
.ok_or(Error::ArithmeticOverflow)
}
fn mint_into_existing_purse(
&mut self,
existing_purse: URef,
amount: U512,
) -> Result<(), Error> {
let caller = self.get_caller();
if caller != PublicKey::System.to_account_hash() {
return Err(Error::InvalidContext);
}
if amount.is_zero() {
return Ok(());
}
if self.read_balance(existing_purse)?.is_none() {
return Err(Error::PurseNotFound);
}
self.add_balance(existing_purse, amount)?;
let total_supply_uref = match self.get_key(TOTAL_SUPPLY_KEY) {
None => {
return Err(Error::TotalSupplyNotFound);
}
Some(Key::URef(uref)) => uref,
Some(_) => return Err(Error::MissingKey),
};
self.add(total_supply_uref, amount)?;
Ok(())
}
}