The Queue's Rules

# The Queue's Rules

The queue is the list of what plays next. It has two parts. On top,
under **Playing next**, are the songs you queued yourself. Below them,
under **Next up**, are the songs that come next in whatever playlist or
album is playing. Your songs always play first.

These are the rules the app follows. The queue tests in `src/app.rs`
check every one of them.

1. **The list is the truth.** The top row plays next, then the second,
   and so on down.

2. **Play next adds a song to your part of the queue.** It goes after
   the songs you queued earlier and before the playlist's songs. Queue
   the same song twice and it plays twice. A double-click only counts
   once.

3. **When a song starts, its row leaves the queue.** It doesn't matter
   how it started: the song before it ended, you pressed Next, you
   clicked it, or another device skipped to it. A song is never shown
   as playing and as next at the same time.

4. **Next removes the top row right away.** The app doesn't wait for
   Spotify to confirm it.

5. **Playing a row from the queue skips to it.** The rows above it are
   skipped and removed, as if you had pressed Next down to it. The rows
   below it stay, and the playlist keeps going afterwards.

6. **Starting a new playlist keeps your songs.** The rows underneath
   change to the new playlist; your songs stay on top and still play
   first.

7. **Clear only removes your songs.** The trash button sits beside the
   *Playing next* heading and empties that section; the playlist's rows
   below stay. It only shows while this computer is the player, because
   that is the only queue the app can actually clear.

8. **The app acts first and tells Spotify after.** Everything above
   happens on screen the moment you do it. When this computer is the
   player, the app tells its own player directly instead of going
   through the Web API.

9. **Closing the app keeps the queue.** Reopen it and the queue is
   there as you left it. It is only a picture until you press play:
   your queued songs are queued again the moment the remembered song
   resumes, and the playlist carries on where it stopped.

10. **Old answers from Spotify are ignored.** Spotify's answers about
   the queue can run a few seconds behind. If an answer is older than
   what you just did, the app throws it away and asks again. A song you
   queued stays on screen until Spotify confirms it. Nothing you do
   disappears and comes back.

The queue is the list of what plays next. It has two parts. On top, under Playing next, are the songs you queued yourself. Below them, under Next up, are the songs that come next in whatever playlist or album is playing. Your songs always play first.

These are the rules the app follows. The queue tests in src/app.rs check every one of them.

The list is the truth. The top row plays next, then the second, and so on down.
Play next adds a song to your part of the queue. It goes after the songs you queued earlier and before the playlist’s songs. Queue the same song twice and it plays twice. A double-click only counts once.
When a song starts, its row leaves the queue. It doesn’t matter how it started: the song before it ended, you pressed Next, you clicked it, or another device skipped to it. A song is never shown as playing and as next at the same time.
Next removes the top row right away. The app doesn’t wait for Spotify to confirm it.
Playing a row from the queue skips to it. The rows above it are skipped and removed, as if you had pressed Next down to it. The rows below it stay, and the playlist keeps going afterwards.
Starting a new playlist keeps your songs. The rows underneath change to the new playlist; your songs stay on top and still play first.
Clear only removes your songs. The trash button sits beside the Playing next heading and empties that section; the playlist’s rows below stay. It only shows while this computer is the player, because that is the only queue the app can actually clear.
The app acts first and tells Spotify after. Everything above happens on screen the moment you do it. When this computer is the player, the app tells its own player directly instead of going through the Web API.
Closing the app keeps the queue. Reopen it and the queue is there as you left it. It is only a picture until you press play: your queued songs are queued again the moment the remembered song resumes, and the playlist carries on where it stopped.
Old answers from Spotify are ignored. Spotify’s answers about the queue can run a few seconds behind. If an answer is older than what you just did, the app throws it away and asks again. A song you queued stays on screen until Spotify confirms it. Nothing you do disappears and comes back.