Prediction market trade modal with mint / swap / merge / redeem functionality

[mzparacha]

Link to Issue

Closes: #13375

Description of Changes

Screen.Recording.2026-02-24.at.11.49.22.PM.mov

Summary

Implements the Prediction Market Trade Modal for minting, swapping, merging, and redeeming PASS/FAIL outcome tokens, aligned with the Futarchy protocol contracts (BinaryVault, FutarchyRouter, UniswapV3Strategy) and the reference logic in app.js / FutarchyGovernor.

Contract integration (predictionMarketTrade.ts)

• Mint: Approve collateral to vault → vault.mint(marketId, amount, collateralAddress).
• Swap: router.getStrategy(marketId) → approve sell token (PASS or FAIL) to strategy → strategy.executeSwap(buyPass, amountIn, minOut). Correct token selection: sell FAIL when buying PASS, sell PASS when buying FAIL.
• Merge: Approve both PASS and FAIL to vault → vault.merge(marketId, amount).
• Redeem: Approve winning token to vault → vault.redeem(marketId, amount) (after market is resolved).
• Helpers: getPredictionMarketBalancesFromChain, getCollateralBalanceAndSymbol, getVaultCollateralBalance, parseTokenAmount, applySlippage, formatTokenDisplay (used in UI).

Modal UI (PredictionMarketTradeModal.tsx + SCSS)

• Header: Title, market prompt, collateral row (symbol, your balance, total minted, market end time).
• Collapsible details: Click-to-expand section with copyable addresses: Vault, Collateral, Router, PASS token, FAIL token, Strategy, Governor (when present), and “Balances for” (wallet). Each row has a copy button; section has a clear border.
• PASS/FAIL balance cards: Display balances (from API or on-chain fallback), with short token address (e.g. 0x6A76…43eA) and copy button on the same line as “PASS BALANCE” / “FAIL BALANCE”; compact styling.
• Tabs: Mint, Swap, Merge, Redeem. Redeem is always clickable; when market is not resolved, in-tab message explains that redemption is available after resolution.
• Mint tab: Amount input, collateral symbol and balance (ERC20 e.g. WETH/USDC), “Available” and MAX using collateral balance; info banner (equal PASS + FAIL received). No protocol-fee summary (contract does not charge a fee).
• Swap tab: “You Sell” / “You Buy” panels with balances and amount; direction toggle; slippage presets (Auto, 0.5%, 1%, 2%, 5%, No min) and custom; “Min. Received” summary. Uses collateral decimals for PASS/FAIL amounts (fixes USDC 6-decimal display). Banner when sell balance is 0 (mint first).
• Merge tab: Amount to merge, “Available” (min of PASS/FAIL), MAX; summary: tokens to burn, 1:1 collateral, “Collateral to be returned” with correct symbol. Uses collateral decimals.
• Redeem tab: Amount input when market is resolved; winning token and max redeem; summary.
• Footer: Cancel + context-specific primary action (Deposit and Mint / Swap / Merge / Redeem). Buttons disabled when amount invalid or exceeds balance (with correct decimals).

Balance and decimals handling

• PASS/FAIL and collateral use collateral token decimals (e.g. 6 for USDC, 18 for WETH) for parsing and display so “Total minted” and balances show correctly.
• When API has no position, PASS/FAIL balances are fetched on-chain and refetched after mint/swap/merge.

Thread card (ThreadPredictionMarketCard.tsx)

• Shows collateral symbol and user balance, total minted (formatted with correct decimals), and opens the trade modal.

Other

• Market type: end_time, strategy_address, governor_address added where used.
• Removed non-existent protocol fee (0.1%) from UI; removed swap summary rows (Exchange Rate, Network Fee, Available ETH) per product; added “Market ends” date in the collateral section.

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Test Plan

Prerequisites

• Wallet connected on the correct chain (e.g. Base Sepolia).
• Community has a prediction market thread with a deployed market (vault, router, p/f tokens, collateral).
• For mint: user has the market’s collateral token (e.g. WETH or USDC).

1. Open modal and header

• From a thread with a prediction market, click “Trade” (or equivalent) to open the trade modal.
• Header shows market title/prompt, collateral symbol, your collateral balance, and “Total minted” (correct decimals for USDC vs WETH).
• “Market ends” shows the correct date/time when end_time is present.
• Collapsible details: collapsed by default; click to expand; Vault, Collateral, Router, PASS token, FAIL token (and Strategy/Governor if API returns them), “Balances for” (wallet) each have a copy button; copying shows “Copied” and pasted value is the full address.

2. PASS/FAIL balance cards

• PASS and FAIL cards show balances (from API or on-chain).
• Each card shows short address (e.g. 0x6A76…43eA) and copy icon on the same line as “PASS BALANCE” / “FAIL BALANCE”.
• Copy button copies the full token address. After mint/swap/merge, balances update (or refetch).

3. Mint

• Mint tab shows “Available: X.XX <symbol>” and MAX uses collateral balance.
• Enter amount <= balance → primary button enabled; submit mints and shows success; modal closes or refreshes; PASS/FAIL balances increase.
• Enter amount > balance → primary button disabled or submit shows “Insufficient <symbol>” error.
• With 0 collateral balance, MAX disabled and message reflects need to hold collateral (e.g. wrap ETH first for WETH).

4. Swap

• Swap tab: “You Sell” FAIL / “You Buy” PASS (or reverse via toggle). Balances and “Min. Received” use correct decimals.
• Enter amount <= sell balance → Swap enabled; submit executes swap; success and balances update.
• Amount > sell balance → Swap disabled or error on submit.
• With 0 sell balance, banner says to mint first; “No min” or high slippage allows swap when pool rate is poor (e.g. “Slippage exceeded” resolved with 5% or “No min”).
• Slippage presets and custom work; “Min. Received” reflects chosen slippage (or “Any PASS/FAIL” for No min).

5. Merge

• Merge tab: “Available” is min(PASS, FAIL); MAX fills that amount.
• Enter amount <= available → Merge enabled; submit merges and returns collateral; success and balances decrease.
• “Collateral to be returned” uses the correct collateral symbol (e.g. USDC, WETH).

6. Redeem

• When market is not resolved: Redeem tab is clickable; in-tab message says redemption is available after resolution; primary button disabled.
• When market is resolved: Enter amount <= winning token balance → Redeem enabled; submit redeems for collateral; success.

7. Edge cases and copy

• Balances for a new wallet (no API position) load from chain and display correctly.
• All copy buttons in the collapsible section and on PASS/FAIL cards copy the correct full address and show “Copied” (or error toast on failure).

8. Manual contract check (optional)

• On Basescan (or chain explorer): vault address holds collateral; PASS/FAIL token balanceOf(user) matches modal after mint/swap/merge.

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Deployment Plan

• No infra or env changes required. Frontend-only; works with existing chain and API.

Other Considerations

• Follow-up: consider a “quote” or expected output for swap (if strategy exposes a view) to improve UX before “Slippage exceeded”.
• Strategy and Governor addresses in the details section depend on API including strategy_address and governor_address in the market payload.