State

Lets an object change its behavior when its internal state changes, by delegating behavior to a state object rather than branching on a status field everywhere.

Why we need this / what value this brings

Replaces scattered if status == X branching with one object per state, each knowing only its own valid transitions and behavior.

When to use this

An object's behavior depends heavily on a status/state field, and that field has more than a couple of states with different valid transitions.

How to use or implement this

Define one class per state implementing a shared interface, have the context object delegate to its current state, and let each state object decide (and perform) the transition to the next.

Research questions

• Booking status (pending → confirmed → completed/cancelled) is the textbook case here — worth checking whether services/bookings centralizes valid transitions in one place or checks status == "..." at each call site.

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Empty folder — drop notes, links, and findings here as you research.