sequenceDiagram

    title: ListService `process()` Sequence Flow

    participant lh as Lambda Handler
    participant l as ListService
    participant ddbu as DynamoDBUtils
    participant ddb as DynamoDB

    lh->>+l: process<br/>(tags?,paginationKey?,count?)

    alt tags provided
    
        l->>+l: listIds()
        note right of l: Refer to `listIds()` sequence diagram
        l-->>-l: [taskIds, paginationKey]

        opt taskids.length > 0
            l->>+l: getItemsFromDb()
            note right of l: Refer to `getItemsFromDb()` sequence diagram
            l-->>-l: tasks
        end
        
    else no tags provided
        l->>+l: listItemsFromDb()
        note right of l: Refer to `listItemsFromDb()` section within `listIds()` sequence diagram
        l-->>-l: [tasks, paginationKey]
    end

    l-->>-lh: [tasks, paginationKey]