`offerId` is updated before it is stored
Summary
The offerId is updated before it is stored.
Vulnerability Details
When creating an offer, the offer id is updated before being stored in offerInfoMap[offerAddr].id and stockInfoMap[stockAddr].id.
https://github.com/Cyfrin/2024-08-tadle/blob/main/src/core/PreMarkets.sol#L83
https://github.com/Cyfrin/2024-08-tadle/blob/main/src/core/PreMarkets.sol#L117
https://github.com/Cyfrin/2024-08-tadle/blob/main/src/core/PreMarkets.sol#L135
So, basically when creating the first offer, offerId = 0, but the id is stored as 1 instead of 0:
offerInfoMap[offerAddr].id = 1stockInfoMap[stockAddr].id = 1
Impact
Wrong storage of id in the mapping.
Tools Used
Recommendations
offerId should be updated at the end of the function createOffer, similar to how it is implemented in the function creatTrade:
https://github.com/Cyfrin/2024-08-tadle/blob/main/src/core/PreMarkets.sol#L253
Lead Judging Commences
finding-PreMarkets-createOffer-offerId-increment-after
I believe this is valid low severity, although there is inconsistency here when using the correct `offerId` for assigning offerIds and generating the unique addresses as seen [here](https://github.com/Cyfrin/2024-08-tadle/blob/04fd8634701697184a3f3a5558b41c109866e5f8/src/core/PreMarkets.sol#L67-L69), this is purely an accounting error for offerIds. If we generate the offerId using current `offerId - 1`, the appropriate listing/taker orders can still be created against those offers.
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