feat(#373-#376): Implement calculate_liquidity_value function and com…

contract/src/leaderboard.rs

@@ -1,6 +1,6 @@
 use crate::errors::InsightArenaError;
 use crate::storage_types::{DataKey, LeaderboardSnapshot, Season, UserProfile};
-use soroban_sdk::{Address, Env, Vec};
+use soroban_sdk::{Address, Env};
 
 /// `stake_bonus = floor(stake_xlm / 10)` → `floor(stake_stroops / 10^8 stroops)`.
 const STROOPS_PER_STAKE_POINT: i128 = 100_000_000;

contract/src/lib.rs

@@ -23,6 +23,7 @@ pub mod ttl;
 pub use crate::config::Config;
 pub use crate::errors::InsightArenaError;
 pub use crate::governance::{Proposal, ProposalType};
+pub use crate::liquidity::{calculate_lp_tokens, calculate_liquidity_value, calculate_swap_output};
 pub use crate::market::CreateMarketParams;
 pub use crate::storage_types::{
     CreatorStats, DataKey, InviteCode, LeaderboardEntry, LeaderboardSnapshot, Market, MarketStats,

contract/src/liquidity.rs

@@ -51,7 +51,29 @@ pub fn calculate_swap_output(
 
 // ── Helper Functions ──────────────────────────────────────────────────────────
 
-// TODO: Add helper functions
+/// Calculate liquidity value for LP tokens (for withdrawal)
+#[allow(dead_code)]
+pub fn calculate_liquidity_value(
+    lp_tokens: i128,
+    total_liquidity: i128,
+    total_lp_supply: i128,
+) -> Result<i128, InsightArenaError> {
+    if lp_tokens <= 0 || total_lp_supply <= 0 {
+        return Err(InsightArenaError::InvalidInput);
+    }
+
+    if lp_tokens > total_lp_supply {
+        return Err(InsightArenaError::InsufficientFunds);
+    }
+
+    let value = lp_tokens
+        .checked_mul(total_liquidity)
+        .ok_or(InsightArenaError::Overflow)?
+        .checked_div(total_lp_supply)
+        .ok_or(InsightArenaError::Overflow)?;
+
+    Ok(value)
+}
 
 // ── Liquidity Management ──────────────────────────────────────────────────────