Octane Example: UseDebouncedValue

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import { useState } from 'octane'
import { createRoot } from 'octane'
import { useDebouncedValue } from '@tanstack/octane-pacer/debouncer'

function App1() {
  const [instantCount, setInstantCount] = useState(0)

  function increment() {
    setInstantCount((c) => c + 1)
  }

  // highest-level hook that watches an instant local state value and returns a debounced value
  const [debouncedCount] = useDebouncedValue(
    instantCount,
    {
      wait: 500,
      // enabled: () => instantCount > 2, // optional, defaults to true
      // leading: true, // optional, defaults to false
    },
    // Alternative to debouncer.Subscribe: pass a selector as 3rd arg to cause re-renders and subscribe to state
    // (state) => state,
  )

  return (
    <div>
      <h1>{'TanStack Pacer useDebouncedValue Example 1'}</h1>
      <table>
        <tbody>
          <tr>
            <td>{'Instant Count:'}</td>
            <td>{instantCount}</td>
          </tr>
          <tr>
            <td>{'Debounced Count:'}</td>
            <td>{debouncedCount}</td>
          </tr>
        </tbody>
      </table>
      <div>
        <button onClick={increment}>{'Increment'}</button>
      </div>
    </div>
  )
}

function App2() {
  const [instantSearch, setInstantSearch] = useState('')

  // highest-level hook that watches an instant local state value and returns a debounced value
  // optionally, grab the debouncer from the last index of the returned array
  const [debouncedSearch] = useDebouncedValue(
    instantSearch,
    {
      wait: 500,
      enabled: instantSearch.length > 2, // optional, defaults to true
    },
    // Alternative to debouncer.Subscribe: pass a selector as 3rd arg to cause re-renders and subscribe to state
    // (state) => state,
  )

  function handleSearchChange(e: Event & { currentTarget: HTMLInputElement }) {
    setInstantSearch(e.currentTarget.value)
  }

  return (
    <div>
      <h1>{'TanStack Pacer useDebouncedValue Example 2'}</h1>
      <div>
        <input
          autoFocus
          type="search"
          value={instantSearch}
          onInput={handleSearchChange}
          placeholder="Type to search..."
          style={{ width: '100%' }}
        />
      </div>
      <table>
        <tbody>
          <tr>
            <td>{'Instant Search:'}</td>
            <td>{instantSearch}</td>
          </tr>
          <tr>
            <td>{'Debounced Search:'}</td>
            <td>{debouncedSearch}</td>
          </tr>
        </tbody>
      </table>
    </div>
  )
}

function App3() {
  const [currentValue, setCurrentValue] = useState(50)
  const [submittedCount, setSubmittedCount] = useState(1)

  // highest-level hook that watches an instant local state value and returns a debounced value
  const [debouncedValue, debouncer] = useDebouncedValue(
    currentValue,
    {
      wait: 250,
    },
    // Alternative to debouncer.Subscribe: pass a selector as 3rd arg to cause re-renders and subscribe to state
    // (state) => state,
  )

  function handleRangeChange(e: Event & { currentTarget: HTMLInputElement }) {
    const newValue = parseInt(e.currentTarget.value, 10)
    setCurrentValue(newValue)
    setSubmittedCount((c) => c + 1)
  }

  return (
    <div>
      <h1>{'TanStack Pacer useDebouncedValue Example 3'}</h1>
      <div style={{ marginBottom: '20px' }}>
        <label>
          {'Current Range:'}
          <input
            type="range"
            min="0"
            max="100"
            value={currentValue}
            onInput={handleRangeChange}
            style={{ width: '100%' }}
          />
          <span>{currentValue}</span>
        </label>
      </div>
      <div style={{ marginBottom: '20px' }}>
        <label>
          {'Debounced Range (Readonly):'}
          <input
            type="range"
            min="0"
            max="100"
            value={debouncedValue}
            disabled
            style={{ width: '100%' }}
          />
          <span>{debouncedValue}</span>
        </label>
      </div>
      <debouncer.Subscribe
        selector={(state) => ({
          isPending: state.isPending,
          executionCount: state.executionCount,
        })}
      >
        {({ isPending, executionCount }) => (
          <>
            <table>
              <tbody>
                <tr>
                  <td>{'Is Pending:'}</td>
                  <td>{isPending.toString()}</td>
                </tr>
                <tr>
                  <td>{'Values Submitted:'}</td>
                  <td>{submittedCount}</td>
                </tr>
                <tr>
                  <td>{'Debounced Executions:'}</td>
                  <td>{executionCount}</td>
                </tr>
                <tr>
                  <td>{'Saved Executions:'}</td>
                  <td>{submittedCount - executionCount}</td>
                </tr>
                <tr>
                  <td>{'% Reduction:'}</td>
                  <td>
                    {submittedCount === 0
                      ? '0'
                      : Math.round(
                          ((submittedCount - executionCount) / submittedCount) *
                            100,
                        )}
                    {'%'}
                  </td>
                </tr>
              </tbody>
            </table>
            <div style={{ color: '#666', fontSize: '0.9em' }}>
              <p>{'Debounced to 250ms wait time'}</p>
            </div>
          </>
        )}
      </debouncer.Subscribe>
      <pre style={{ marginTop: '20px' }}>
        <debouncer.Subscribe selector={(state) => state}>
          {(state) => JSON.stringify(state, null, 2)}
        </debouncer.Subscribe>
      </pre>
    </div>
  )
}

function PacerExample() {
  return (
    <div>
      <App1 />
      <hr />
      <App2 />
      <hr />
      <App3 />
    </div>
  )
}
createRoot(document.getElementById('app')!).render(PacerExample)