Files
simple-rust-tests/__crypto/simple_contract/src/credit.rs
2021-01-01 23:42:15 +08:00

83 lines
2.6 KiB
Rust

use std::collections::HashMap;
use serde::{Serialize, Deserialize};
use rust_util::XResult;
use crate::tx::Transaction;
#[derive(Debug, Serialize, Deserialize)]
pub struct CreditContract {
pub name: String,
pub credit_limit: u32,
pub issue_amount: u32,
pub admin: String,
pub credit: HashMap<String, u32>,
}
impl CreditContract {
pub fn new(tx: &Transaction, name: &str, credit_limit: u32) -> XResult<Self> {
let c = Self {
name: name.into(),
credit_limit,
issue_amount: 0,
admin: tx.sender.clone(),
credit: HashMap::new(),
};
Ok(c)
}
pub fn issue(&mut self, tx: &Transaction, receiver: &str, credit: u32) -> XResult<()> {
if &self.admin != &tx.sender {
return simple_error!("Current user is not admin, {} vs {:?}", self.admin, tx.sender);
}
if credit == 0 {
return simple_error!("Cannot issue 0 credit!");
}
if self.issue_amount + credit > self.credit_limit {
return simple_error!(
"Issue too much credit, current: {}, issue: {}, limit: {}, left: {}",
self.issue_amount,
credit,
self.credit_limit,
self.credit_limit - self.issue_amount
);
}
match self.credit.get_mut(receiver) {
None => { self.credit.insert(receiver.to_owned(), credit); },
Some(cr) => *cr += credit,
}
self.issue_amount += credit;
Ok(())
}
pub fn transfer(&mut self, tx: &Transaction, receiver: &str, credit: u32) -> XResult<()> {
if credit == 0 {
return simple_error!("Cannot transfer 0 credit!");
}
match self.credit.get_mut(&tx.sender) {
None => return simple_error!("Have not enough credit: {:?}", tx.sender),
Some(cr) => {
if *cr >= credit {
*cr -= credit;
match self.credit.get_mut(receiver) {
None => { self.credit.insert(receiver.to_owned(), credit); },
Some(receiver_credit) => *receiver_credit += credit,
}
} else {
return simple_error!("Have not enough credit: {:?}", tx.sender);
}
},
}
Ok(())
}
pub fn query(&self, _tx: &Transaction, account: &str) -> u32 {
match self.credit.get(account) {
None => 0,
Some(receiver_credit) => *receiver_credit,
}
}
pub fn query_all(&self, _tx: &Transaction) -> &HashMap<String, u32> {
&self.credit
}
}