Bid Types

In Basta, every bid is either a MaxBid or a NormalBid. These types define how the auction engine responds when bids are placed — either reactively (MaxBid) or directly (NormalBid).

📈 MaxBid

A MaxBid allows a user to define the maximum amount they're willing to pay. The auction engine will automatically place incremental bids on their behalf until:

They win the item

They are outbid by a higher max bid

Or their maximum amount is reached

⚙️ MaxBid Highlights

Bids follow the Bid Increment Table

The winning amount may be lower than the max amount

If outbid, the engine reacts automatically (unless max is reached)

📘 Example: MaxBid Behavior

Bid Increment Table

LowRange	HighRange	Step
0	200000	1000

startingBid: 1000

Bid Flow

User-1 places MaxBid of 5000

User-2 places MaxBid of 3000

System places a reactive bid for User-1 at 4000

Resulting State

UserID	MaxBid Amount	Winning Amount	Active MaxBid	Bid Accepted
User-1	5000	1000	5000	✅
User-2	3000	3000	3000	✅
User-1	—	4000	5000	✅ (reactive)

💬

Explanation

Although User-2 places a valid MaxBid of 3000 they are never the leading bidder.

As soon as their bid is placed, the system automatically places a reactive bid for User-1

at 4000. This means User-2 is immediately outbid, and their MaxBid is recorded as losing.

🧾 NormalBid

A NormalBid is a one-time bid at a specified amount. It must align with the bid increment table and does not react to counter-bids.

📘 Example: NormalBid Behavior

UserID	NormalBid Amount	Winning Amount	Active MaxBid	Bid Accepted
User-1	5000	5000	0	✅
User-2	3000	—	0	❌ (too low)
User-2	8000	8000	0	✅

⚠️ Edge Cases to Know

🟰 Equal MaxBids

If two users place identical MaxBids, the first bidder wins

The second bid is accepted but marked as losing

🔄 MaxBid overtakes NormalBid

If a NormalBid leads and a MaxBid is placed after, the engine will outbid it reactively, assuming the MaxBid is higher

🚫 MaxBid below Reserve

Even if a user is winning, they must meet the item's Reserve or no winner is declared