Trading contracts

TwoWayConstantProductFactory

• constructor(ISecurityPoolFactory, uint256 feeBps) fixes the core factory and fee; feeBps < 10,000.
• createPair(ISecurityPool) validates the exact canonical pool, deploys with CREATE2, and returns the existing canonical pair on duplicate calls.
• getPair(ISecurityPool) → pair maps exact pool identity to a pair.
• isPair(address) → bool recognizes router-eligible pairs.
• predictPair(ISecurityPool) → address calculates the CREATE2 address.
• securityPoolFactory(), feeBps(), and predeploymentShareSink() expose immutable configuration.

Canonical validation requires the pool's own securityPoolFactory, the factory's (originId, universeId) lookup, and shareToken.canonicalPoolByUniverse(universeId) all to agree.

CREATE2 pair addresses exist counterfactually before code is deployed, when ERC-1155 receiver checks cannot run. Each factory therefore deploys an ownerless PredeploymentShareSink. A pair constructor transfers any canonical INVALID, YES, or NO already present at its future address into that sink before returning. Those quarantined shares are permanently inaccessible; do not send shares to a predicted pair address.

TwoWayConstantProductPair

Immutable accessors expose factory, securityPool, shareToken, universeId, questionId, invalidTokenId, yesTokenId, noTokenId, and feeBps. LP ERC-20 accessors are name, symbol, decimals, totalSupply, balanceOf, allowance, approve, transfer, and transferFrom.

• getReserves() returns recorded YES and NO reserves.
• tradingStatus() returns Open, QuestionEnded, PoolInactive, AwaitingForkContinuation, UniverseForked, QuestionResolved, or Uninitialized.
• initialize(yesAmount, noAmount, minLiquidity, recipient) pulls the first reserves, locks MINIMUM_LIQUIDITY, and mints the remainder once.
• addLiquidity(maxYes, maxNo, minLiquidity, recipient) synchronizes donations, selects the largest proportional amounts, pulls them, and mints LP.
• removeLiquidity(liquidity, minYes, minNo, recipient, deadline) burns caller LP and returns proportional raw shares before the deadline. It has no lifecycle-close guard.
• swapExactInput(yesForNo, amountIn, minAmountOut, recipient) pulls the gross input and sends the floor-rounded output.
• swapExactOutput(yesForNo, amountOut, maxAmountIn, recipient) pulls the ceil-rounded required input and sends the exact output.
• quoteExactInput and quoteExactOutput quote against effective balances including donations.
• sync() records authoritative balances, reverting if balances fell below reserves or INVALID is present.
• onERC1155Received, onERC1155BatchReceived, and supportsInterface implement receiver discovery. Only the canonical ShareToken's exact YES/NO IDs are accepted. Pre-initialization transfers must be initiated by the pair's own pull.

tradingStatus() is a concise action blocker, not an authoritative settlement summary. The first matching condition wins in this order: Uninitialized, UniverseForked, AwaitingForkContinuation, PoolInactive, QuestionResolved, QuestionEnded, then Open. An uninitialized forked pair therefore reports Uninitialized, and a finalized question reports QuestionResolved even after its end time. Read SecurityPoolForker.getQuestionOutcome(pool) when the finalized outcome itself is required.

PredeploymentShareSink

Accepts ERC-1155 transfers and has no withdrawal or administrative method. It exists only to preserve clean pair initialization and the zero-INVALID invariant after counterfactual-address poisoning attempts.

TwoWayConstantProductMath

The internal library provides exact-input and exact-output quotes, ceil rounding through the repository's full-precision Math.mulDiv, proportional deposits, initial odds, and conditional price basis points. Production paths never multiply reserve products. Rounding directions are listed in Units and rounding.