Add legacy SC: farm staking proxy v1.3

Cargo.toml

@@ -37,6 +37,8 @@ members = [
   "farm-staking/metabonding-staking",
   "farm-staking/metabonding-staking/meta",
 
+  "legacy-contracts/farm-staking-proxy-v1.3",
+  "legacy-contracts/farm-staking-proxy-v1.3/meta",
   "legacy-contracts/simple-lock-legacy",
   "legacy-contracts/simple-lock-legacy/meta",
 

legacy-contracts/farm-staking-proxy-v1.3/Cargo.toml

@@ -0,0 +1,43 @@
+[package]
+name = "farm-staking-legacy"
+version = "0.0.0"
+authors = [ "you",]
+edition = "2018"
+publish = false
+
+[lib]
+path = "src/lib.rs"
+
+[dependencies.config]
+path = "../../common/modules/farm/config"
+
+[dependencies.farm_token]
+path = "../../common/modules/farm/farm_token"
+
+[dependencies.rewards]
+path = "../../common/modules/farm/rewards"
+
+[dependencies.token_send]
+path = "../../common/modules/token_send"
+
+[dependencies.token_merge_helper]
+path = "../../common/modules/token_merge_helper"
+
+[dependencies.common_structs]
+path = "../../common/common_structs"
+
+[dependencies.common_errors]
+path = "../../common/common_errors"
+
+[dev-dependencies.multiversx-sc-scenario]
+version = "=0.48.1"
+
+[dev-dependencies.multiversx-sc-modules]
+version = "=0.48.1"
+
+[dependencies.multiversx-sc]
+version = "=0.48.1"
+features = ["esdt-token-payment-legacy-decode"]
+
+[dev-dependencies]
+num-bigint = "0.4.2"

legacy-contracts/farm-staking-proxy-v1.3/docs/setup.md

@@ -0,0 +1,85 @@
+# Farm Staking setup steps
+
+## Deployment
+
+The init function takes the following arguments:
+- farming_token_id - the farming token ID, which will also be the reward token
+- division_safety_constant - used in some calculations for precision. I suggest something like 10^9.
+- max_apr - a percentage of max APR, which will limit the user's rewards, with two decimals precision (i.e. 10_000 = 100%). Can be more than 100%.
+- min_unbond_epochs - Number of epochs the user has to wait between unstake and unbond.
+```
+#[init]
+fn init(
+    &self,
+    farming_token_id: TokenIdentifier,
+    division_safety_constant: BigUint,
+    max_apr: BigUint,
+    min_unbond_epochs: u64,
+)
+```
+
+## Additional config
+
+### Setup farm token
+
+You have to register/issue the farm token and set its local roles, which is the token used for positions in the staking contract. This is done through the following endpoints:
+
+```
+#[payable("EGLD")]
+#[endpoint(registerFarmToken)]
+fn register_farm_token(
+    &self,
+    #[payment_amount] register_cost: BigUint,
+    token_display_name: ManagedBuffer,
+    token_ticker: ManagedBuffer,
+    num_decimals: usize,
+)
+```
+
+For issue parameters format restrictions, take a look here: https://docs.multiversx.com/tokens/esdt-tokens/#parameters-format
+
+payment_amount should be `0.05 EGLD`.
+
+```
+#[endpoint(setLocalRolesFarmToken)]
+fn set_local_roles_farm_token(&self)
+```
+
+### Set per block rewards
+
+```
+#[endpoint(setPerBlockRewardAmount)]
+fn set_per_block_rewards(&self, per_block_amount: BigUint)
+```
+
+Keep in mind amount has to take into consideration the token's decimals. So if you have a token with 18 decimals, you have to pass 10^18 for "1".
+
+### Add the reward tokens
+
+```
+#[payable("*")]
+#[endpoint(topUpRewards)]
+fn top_up_rewards(
+    &self,
+    #[payment_token] payment_token: TokenIdentifier,
+    #[payment_amount] payment_amount: BigUint,
+)
+```
+
+No args needed, you only need to pay the reward tokens. In the staking farm, rewards are not minted, but added by the owner.
+
+### Final steps
+
+First, you have to enable rewards generation:
+
+```
+#[endpoint(startProduceRewards)]
+fn start_produce_rewards(&self)
+```
+
+Then, you have to the set the state to active:
+
+```
+#[endpoint]
+fn resume(&self)
+```

legacy-contracts/farm-staking-proxy-v1.3/meta/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "farm-staking-legacy-abi"
+
+version = "0.0.0"
+authors = [ "you",]
+edition = "2018"
+publish = false
+
+[dependencies.farm-staking-legacy]
+path = ".."
+
+[dependencies.multiversx-sc-meta]
+version = "0.48.1"
+default-features = false

legacy-contracts/farm-staking-proxy-v1.3/meta/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    multiversx_sc_meta::cli_main::<farm_staking::AbiProvider>();
+}

legacy-contracts/farm-staking-proxy-v1.3/multiversx.json

@@ -0,0 +1,3 @@
+{
+    "language": "rust"
+}

legacy-contracts/farm-staking-proxy-v1.3/src/custom_rewards.rs

@@ -0,0 +1,186 @@
+multiversx_sc::imports!();
+multiversx_sc::derive_imports!();
+
+use common_structs::Nonce;
+use config::MAX_PERCENT;
+
+pub const BLOCKS_IN_YEAR: u64 = 31_536_000 / 6; // seconds_in_year / 6_seconds_per_block
+
+#[multiversx_sc::module]
+pub trait CustomRewardsModule:
+    config::ConfigModule + token_send::TokenSendModule + farm_token::FarmTokenModule
+{
+    fn calculate_extra_rewards_since_last_allocation(&self) -> BigUint {
+        let current_block_nonce = self.blockchain().get_block_nonce();
+        let last_reward_nonce = self.last_reward_block_nonce().get();
+
+        if current_block_nonce > last_reward_nonce {
+            let extra_rewards_unbounded =
+                self.calculate_per_block_rewards(current_block_nonce, last_reward_nonce);
+
+            let farm_token_supply = self.farm_token_supply().get();
+            let extra_rewards_apr_bounded_per_block =
+                self.get_amount_apr_bounded(&farm_token_supply);
+
+            let block_nonce_diff = current_block_nonce - last_reward_nonce;
+            let extra_rewards_apr_bounded = extra_rewards_apr_bounded_per_block * block_nonce_diff;
+
+            self.last_reward_block_nonce().set(&current_block_nonce);
+
+            core::cmp::min(extra_rewards_unbounded, extra_rewards_apr_bounded)
+        } else {
+            BigUint::zero()
+        }
+    }
+
+    fn generate_aggregated_rewards(&self) {
+        let mut extra_rewards = self.calculate_extra_rewards_since_last_allocation();
+        if extra_rewards > 0 {
+            let mut accumulated_rewards = self.accumulated_rewards().get();
+            let total_rewards = &accumulated_rewards + &extra_rewards;
+            let reward_capacity = self.reward_capacity().get();
+            if total_rewards > reward_capacity {
+                let amount_over_capacity = total_rewards - reward_capacity;
+                extra_rewards -= amount_over_capacity;
+            }
+
+            accumulated_rewards += &extra_rewards;
+            self.accumulated_rewards().set(&accumulated_rewards);
+
+            self.update_reward_per_share(&extra_rewards);
+        }
+    }
+
+    #[only_owner]
+    #[payable("*")]
+    #[endpoint(topUpRewards)]
+    fn top_up_rewards(&self) {
+        let (payment_amount, payment_token) = self.call_value().payment_token_pair();
+        let reward_token_id = self.reward_token_id().get();
+        require!(payment_token == reward_token_id, "Invalid token");
+
+        self.reward_capacity().update(|r| *r += payment_amount);
+    }
+
+    #[only_owner]
+    #[endpoint]
+    fn end_produce_rewards(&self) {
+        self.generate_aggregated_rewards();
+        self.produce_rewards_enabled().set(&false);
+    }
+
+    #[only_owner]
+    #[endpoint(setPerBlockRewardAmount)]
+    fn set_per_block_rewards(&self, per_block_amount: BigUint) {
+        require!(per_block_amount != 0, "Amount cannot be zero");
+
+        self.generate_aggregated_rewards();
+        self.per_block_reward_amount().set(&per_block_amount);
+    }
+
+    #[only_owner]
+    #[endpoint(setMaxApr)]
+    fn set_max_apr(&self, max_apr: BigUint) {
+        require!(max_apr != 0, "Max APR cannot be zero");
+
+        self.max_annual_percentage_rewards().set(&max_apr);
+    }
+
+    #[only_owner]
+    #[endpoint(setMinUnbondEpochs)]
+    fn set_min_unbond_epochs(&self, min_unbond_epochs: u64) {
+        self.min_unbond_epochs().set(&min_unbond_epochs);
+    }
+
+    fn calculate_per_block_rewards(
+        &self,
+        current_block_nonce: Nonce,
+        last_reward_block_nonce: Nonce,
+    ) -> BigUint {
+        if current_block_nonce <= last_reward_block_nonce || !self.produces_per_block_rewards() {
+            return BigUint::zero();
+        }
+
+        let per_block_reward = self.per_block_reward_amount().get();
+        let block_nonce_diff = current_block_nonce - last_reward_block_nonce;
+
+        per_block_reward * block_nonce_diff
+    }
+
+    fn update_reward_per_share(&self, reward_increase: &BigUint) {
+        let farm_token_supply = self.farm_token_supply().get();
+        if farm_token_supply > 0 {
+            let increase =
+                self.calculate_reward_per_share_increase(reward_increase, &farm_token_supply);
+            self.reward_per_share().update(|r| *r += increase);
+        }
+    }
+
+    fn calculate_reward_per_share_increase(
+        &self,
+        reward_increase: &BigUint,
+        farm_token_supply: &BigUint,
+    ) -> BigUint {
+        &(reward_increase * &self.division_safety_constant().get()) / farm_token_supply
+    }
+
+    fn calculate_reward(
+        &self,
+        amount: &BigUint,
+        current_reward_per_share: &BigUint,
+        initial_reward_per_share: &BigUint,
+    ) -> BigUint {
+        if current_reward_per_share > initial_reward_per_share {
+            let reward_per_share_diff = current_reward_per_share - initial_reward_per_share;
+            amount * &reward_per_share_diff / self.division_safety_constant().get()
+        } else {
+            BigUint::zero()
+        }
+    }
+
+    fn get_amount_apr_bounded(&self, amount: &BigUint) -> BigUint {
+        let max_apr = self.max_annual_percentage_rewards().get();
+        amount * &max_apr / MAX_PERCENT / BLOCKS_IN_YEAR
+    }
+
+    #[only_owner]
+    #[endpoint(startProduceRewards)]
+    fn start_produce_rewards(&self) {
+        require!(
+            self.per_block_reward_amount().get() != 0,
+            "Cannot produce zero reward amount"
+        );
+        require!(
+            !self.produce_rewards_enabled().get(),
+            "Producing rewards is already enabled"
+        );
+        let current_nonce = self.blockchain().get_block_nonce();
+        self.produce_rewards_enabled().set(&true);
+        self.last_reward_block_nonce().set(&current_nonce);
+    }
+
+    #[inline(always)]
+    fn produces_per_block_rewards(&self) -> bool {
+        self.produce_rewards_enabled().get()
+    }
+
+    #[view(getRewardPerShare)]
+    #[storage_mapper("reward_per_share")]
+    fn reward_per_share(&self) -> SingleValueMapper<BigUint>;
+
+    #[view(getAccumulatedRewards)]
+    #[storage_mapper("accumulatedRewards")]
+    fn accumulated_rewards(&self) -> SingleValueMapper<BigUint>;
+
+    #[view(getRewardCapacity)]
+    #[storage_mapper("reward_capacity")]
+    fn reward_capacity(&self) -> SingleValueMapper<BigUint>;
+
+    #[view(getAnnualPercentageRewards)]
+    #[storage_mapper("annualPercentageRewards")]
+    fn max_annual_percentage_rewards(&self) -> SingleValueMapper<BigUint>;
+
+    #[view(getMinUnbondEpochs)]
+    #[storage_mapper("minUnbondEpochs")]
+    fn min_unbond_epochs(&self) -> SingleValueMapper<u64>;
+}