stateDiagram-v2 direction TB [*] --> Greeting Greeting --> CollectDestination: flight intent CollectDestination --> CollectDestination: unclear input CollectDestination --> CollectOrigin: provides destination CollectOrigin --> CollectDate: provides origin CollectDate --> CollectTime: date validated CollectTime --> AllSlotsFilled: provides time AllSlotsFilled --> CollectDestination: NO - missing slot AllSlotsFilled --> DisplayOptions: YES - all collected DisplayOptions --> CollectDate: changes criteria DisplayOptions --> ConfirmSelection: picks a flight ConfirmSelection --> BookingComplete: confirms BookingComplete --> [*] Greeting: Greeting CollectDestination: Collect Destination CollectOrigin: Collect Origin CollectDate: Collect Date CollectTime: Collect Time Preference AllSlotsFilled: All Slots Filled? DisplayOptions: Display Options ConfirmSelection: Confirm Selection BookingComplete: Booking Complete classDef startState fill:#2e7d32,stroke:#1b5e20,stroke-width:2px,color:#fff,font-size:15px classDef gatherState fill:#1976d2,stroke:#0d47a1,stroke-width:2px,color:#fff,font-size:15px classDef decisionState fill:#f9a825,stroke:#f57f17,stroke-width:2px,color:#000,font-size:15px classDef txnState fill:#ef6c00,stroke:#e65100,stroke-width:2px,color:#fff,font-size:15px classDef endState fill:#6a1b9a,stroke:#4a148c,stroke-width:2px,color:#fff,font-size:15px class Greeting startState class CollectDestination,CollectOrigin,CollectDate,CollectTime gatherState class AllSlotsFilled decisionState class DisplayOptions,ConfirmSelection txnState class BookingComplete endState