Return min and max stake values in tBTC precision

To avoid confusion of mixing precisions in the contract, we decidwed to
use tBTC precision consistently across the contract and its' API.
It will be dApp/SDK responsibility to convert to satoshi precision in
staking flow.

core/contracts/AcreBitcoinDepositor.sol

@@ -466,16 +466,16 @@ contract AcreBitcoinDepositor is AbstractTBTCDepositor, Ownable2Step {
         tbtcToken.safeTransfer(staker, amount);
     }
 
-    /// @notice Minimum stake amount in satoshi precision.
+    /// @notice Minimum stake amount (in tBTC token precision).
     /// @dev This function should be used by dApp to check the minimum amount
     ///      for the stake request.
     /// @dev It is not enforced in the `initializeStakeRequest` function, as
     ///      it is intended to be used in the dApp staking form.
-    function minStakeInSatoshi() external view returns (uint256) {
-        return minStakeAmount / SATOSHI_MULTIPLIER;
+    function minStake() external view returns (uint256) {
+        return minStakeAmount;
     }
 
-    /// @notice Maximum stake amount in satoshi precision.
+    /// @notice Maximum stake amount (in tBTC token precision).
     /// @dev It takes into consideration the maximum total assets soft limit (soft
     ///      cap), that is expected to be set below the stBTC maximum total assets
     ///      limit (hard cap).
@@ -486,7 +486,7 @@ contract AcreBitcoinDepositor is AbstractTBTCDepositor, Ownable2Step {
     ///      submission of Bitcoin funding transaction and stake request
     ///      initialization.
     /// @return Maximum allowed stake amount.
-    function maxStakeInSatoshi() external view returns (uint256) {
+    function maxStake() external view returns (uint256) {
         uint256 currentTotalAssets = stbtc.totalAssets();
 
         if (currentTotalAssets >= maxTotalAssetsSoftLimit) {
@@ -500,9 +500,7 @@ contract AcreBitcoinDepositor is AbstractTBTCDepositor, Ownable2Step {
         }
         availableLimit -= queuedStakesBalance;
 
-        uint256 result = Math.min(availableLimit, maxSingleStakeAmount);
-
-        return result / SATOSHI_MULTIPLIER;
+        return Math.min(availableLimit, maxSingleStakeAmount);
     }
 
     /// @notice Updates the minimum stake amount.

core/test/AcreBitcoinDepositor.test.ts

@@ -31,8 +31,6 @@ const { lastBlockTime } = helpers.time
 const { getNamedSigners, getUnnamedSigners } = helpers.signers
 
 describe("AcreBitcoinDepositor", () => {
-  const satoshiMultiplier = 10n ** 10n
-
   const defaultDepositDustThreshold = 1000000 // 1000000 satoshi = 0.01 BTC
   const defaultDepositTreasuryFeeDivisor = 2000 // 1/2000 = 0.05% = 0.0005
   const defaultDepositTxMaxFee = 1000 // 1000 satoshi = 0.00001 BTC
@@ -1409,7 +1407,7 @@ describe("AcreBitcoinDepositor", () => {
     })
   })
 
-  describe("maxStakeInSatoshi", () => {
+  describe("maxStake", () => {
     beforeAfterSnapshotWrapper()
 
     const maxTotalAssetsSoftLimit = to1ePrecision(100000000, 10) // 100000000 satoshi = 1 BTC
@@ -1431,7 +1429,7 @@ describe("AcreBitcoinDepositor", () => {
       })
 
       it("should return 0", async () => {
-        expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(0)
+        expect(await bitcoinDepositor.maxStake()).to.be.equal(0)
       })
     })
 
@@ -1458,7 +1456,7 @@ describe("AcreBitcoinDepositor", () => {
         })
 
         it("should return 0", async () => {
-          expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(0)
+          expect(await bitcoinDepositor.maxStake()).to.be.equal(0)
         })
       })
 
@@ -1484,15 +1482,15 @@ describe("AcreBitcoinDepositor", () => {
           })
 
           it("should return zero", async () => {
-            expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(0)
+            expect(await bitcoinDepositor.maxStake()).to.be.equal(0)
           })
         })
 
         describe("max single stake amount is less than the available limit", () => {
           beforeAfterSnapshotWrapper()
 
           const maxSingleStakeAmount = to1ePrecision(20000000, 10) // 20000000 satoshi = 0.2 BTC
-          const expectedResult = toSatoshi(maxSingleStakeAmount)
+          const expectedResult = maxSingleStakeAmount
 
           before(async () => {
             await bitcoinDepositor
@@ -1501,7 +1499,7 @@ describe("AcreBitcoinDepositor", () => {
           })
 
           it("should return max single stake amount", async () => {
-            expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(
+            expect(await bitcoinDepositor.maxStake()).to.be.equal(
               expectedResult,
             )
           })
@@ -1511,7 +1509,7 @@ describe("AcreBitcoinDepositor", () => {
           beforeAfterSnapshotWrapper()
 
           const maxSingleStakeAmount = to1ePrecision(35000000, 10) // 35000000 satoshi = 0.35 BTC
-          const expectedResult = toSatoshi(availableSoftLimitMinusQueue)
+          const expectedResult = availableSoftLimitMinusQueue
 
           before(async () => {
             await bitcoinDepositor
@@ -1520,57 +1518,12 @@ describe("AcreBitcoinDepositor", () => {
           })
 
           it("should return available limit", async () => {
-            expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(
+            expect(await bitcoinDepositor.maxStake()).to.be.equal(
               expectedResult,
             )
           })
         })
       })
-
-      describe("when available limit is equal to the satoshi multiplier", () => {
-        beforeAfterSnapshotWrapper()
-
-        before(async () => {
-          await tbtc.mint(
-            await stbtc.getAddress(),
-            availableSoftLimit - satoshiMultiplier,
-          )
-        })
-
-        it("should return 1", async () => {
-          expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(1)
-        })
-      })
-
-      describe("when available limit is less than the satoshi multiplier", () => {
-        beforeAfterSnapshotWrapper()
-
-        before(async () => {
-          await tbtc.mint(
-            await stbtc.getAddress(),
-            availableSoftLimit - satoshiMultiplier + 1n,
-          )
-        })
-
-        it("should return 0", async () => {
-          expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(0)
-        })
-      })
-
-      describe("when available limit is greater than the satoshi multiplier", () => {
-        beforeAfterSnapshotWrapper()
-
-        before(async () => {
-          await tbtc.mint(
-            await stbtc.getAddress(),
-            availableSoftLimit - satoshiMultiplier - 1n,
-          )
-        })
-
-        it("should return 1", async () => {
-          expect(await bitcoinDepositor.maxStakeInSatoshi()).to.be.equal(1)
-        })
-      })
     })
   })
 
@@ -1968,8 +1921,4 @@ describe("AcreBitcoinDepositor", () => {
       await tbtcVault.finalizeOptimisticMintingRequest(depositKey)
     }
   }
-
-  function toSatoshi(tbtcAmount: bigint) {
-    return tbtcAmount / satoshiMultiplier
-  }
 })