refactor: reduce code from polkadot lib by replacing BN and HexString import from @polkadot/util

[vutuanlinh2k2]

Summary of changes

• Replace BN, HexString types usage from @polkadot/util to internal and viem
• Minor code refactors (remove redundant and duplicate code

Proposed area of change

Put an x in the boxes that apply.

• apps/tangle-dapp
• apps/tangle-cloud
• apps/leaderboard
• libs/tangle-shared-ui
• libs/ui-components

Associated issue(s)

Specify any issues that can be closed from these changes (e.g. Closes #233).

• Closes [TASK] Replace Big Number usages from @polkadot/util across dapps #3074

[claude]

Claude finished @vutuanlinh2k2's task —— View job

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PR Review: BN and HexString Refactor

I've completed a comprehensive review of this refactoring PR. Here's my analysis:

✅ Overall Assessment: Good Refactor

This is a well-executed refactoring that reduces dependency on @polkadot/util while maintaining functionality. The approach is sound and follows the codebase patterns.

📋 Code Quality & Best Practices

✅ Strengths:

• Proper centralization: New BN utilities in libs/tangle-shared-ui/src/bn/ follow the monorepo structure
• Consistent import patterns: All files now import BN from the internal utility
• Clean consolidation: Moved useInputAmount from tangle-dapp to shared library (good DRY principle)
• Type safety maintained: BN types remain consistent throughout

✅ Good utility implementations:

• bnMax/bnMin functions in utils.ts are well-implemented with proper error handling
• formatDecimal utility is clean and well-documented with examples
• Constants file provides commonly used BN values

🔍 Potential Issues Found

⚠️ Incomplete Migration:

Several files still import from @polkadot/util:

• libs/ui-components/src/utils/convertAddressToBytes32.ts:4 - imports u8aToHex
• libs/tangle-shared-ui/src/utils/optimizeTxBatch.ts
• libs/tangle-shared-ui/src/hooks/useOperatorInfo.tsx
• apps/tangle-dapp/src/utils/getSubstrateLockId.ts

Recommendation: Complete the migration by replacing these remaining imports for full consistency.

⚠️ Missing HexString handling:

The PR mentions HexString refactoring but I don't see a clear replacement strategy. Some files may still need HexString functionality.

🏎️ Performance Considerations

✅ Positive impacts:

• Reduced bundle size: Fewer polkadot/util imports mean smaller bundles
• Faster builds: Less dependency on heavy polkadot libraries
• Better tree-shaking: Internal utilities allow better optimization

⚠️ Potential concerns:

• BN operations remain the same performance-wise
• No significant performance regression expected

🛡️ Security Implications

✅ No security concerns:

• BN.js is still the underlying library, just imported differently
• Number precision handling remains intact
• No changes to cryptographic operations

📚 Documentation Updates Needed

❌ Missing documentation:

• New BN utilities (libs/tangle-shared-ui/src/bn/utils.ts) need JSDoc comments
• Constants file could benefit from usage examples
• No CLAUDE.md updates needed as this follows existing patterns

🧪 Testing Considerations

⚠️ Test coverage:

• Large refactor across 100 files should be thoroughly tested
• Consider adding unit tests for the new BN utilities
• Integration tests should verify number handling still works correctly

🔧 Specific Code Comments

libs/tangle-shared-ui/src/bn/utils.ts:3-24

The createCmp function is well-designed but could benefit from JSDoc:

/**
 * Creates a comparison function for BN values
 * @param cmp - Comparison predicate function
 * @returns Function that returns the item matching the comparison
 */
function createCmp<T>(cmp: (a: T, b: T) => boolean): (...items: T[]) => T

apps/tangle-dapp/src/utils/parseChainUnits.ts:25

The TODO comment indicates a known bug that should be addressed:

// TODO: Small bug remains for the special case when the whole part is 0. 
// Example: '0.01' gets parsed as '0.1'!

🎯 Recommendations

1. Complete the migration by replacing remaining @polkadot/util imports
2. Add JSDoc comments to new utility functions
3. Address the parseChainUnits bug mentioned in the TODO
4. Run comprehensive tests to ensure number handling works correctly
5. Consider adding unit tests for the new BN utilities

🚀 Final Verdict

✅ APPROVE - This is a solid refactoring that improves the codebase structure. The minor issues mentioned can be addressed in follow-up PRs or quick fixes.

The refactor successfully reduces external dependencies while maintaining functionality and follows good software engineering practices.

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