import { Query } from '@tanstack/db'

const myQuery = new Query()
  .from(...)
  .where(...)

const liveQueryCollection = createCollection(liveQueryCollectionOptions({
  query: myQuery,
}))
// or
const { data } = useLiveQuery({
  query: myQuery,
})

import type { Ref } from '@tanstack/db'

const userIsAdult = ({ user }: { user: Ref<User> }) => gt(user.age, 18)

const userIsActive = ({ user }: { user: Ref<User> }) =>
  eq(user.active, true)

const userIsYoung = ({ user }: { user: Ref<User> }) => lt(user.age, 25)

// Use the predicates in a query
const myQuery = new Query()
  .from({ user: usersCollection })
  .where(userIsAdult)
  .where(userIsActive)
  .where(userIsYoung)

// Define reusable select objects using defineForRow
const userBasicInfo = ({ user }: { user: Ref<User> }) => ({
  id: user.id,
  name: user.name,
  email: user.email,
})

const userNameTransforms = ({ user }: { user: Ref<User> }) => ({
  nameUpper: upper(user.name),
  nameLower: lower(user.name),
})

// Use the select objects in a query
const myQuery = new Query()
  .from({ user: usersCollection })
  .where(({ user }) => eq(user.active, true))
  .select(({ user }) => ({
    ...userBasicInfo({ user }),
    ...userNameTransforms({ user }),
    age: user.age,
  }))