lintunes/cassette.md

Sharing music with friends (Cassette)

Cassette lets you subscribe to friends' playlists, peek at their libraries and download their songs via a program called Syncthing.

1. Install and start Syncthing (once)

Open a terminal and paste the line for your distro:

sudo apt install syncthing        # Debian / Ubuntu / Mint
sudo dnf install syncthing        # Fedora

Then start it, and have it start by itself every time you log in:

systemctl --user enable --now syncthing

To check it's running, open http://127.0.0.1:8384 in your web browser — you should see Syncthing's page. You don't have to do anything there; the default settings (including "global discovery" and "relaying", which let two computers find each other across the internet) are exactly right.

Already using Syncthing to keep your library on two of your own computers? Great — nothing changes. Only one of your computers handles friends; LinTunes asks which the first time (see below), and songs it brings in reach your other computers the usual way.

2. Connect with a friend

One of you invites, the other pastes. It doesn't matter who.

If you're inviting: in LinTunes choose Connections ▸ Share Library with a Friend…. The very first time, LinTunes asks "Use this computer for sharing with friends?" — say Yes. You'll get an invite code: a long line starting with LTC1. Press Copy Code and send it to your friend however you like (text, email, chat). Each code works for one friend, once.

If you were sent a code: choose Connections ▸ Add Friend Library…, paste the whole code into the box, and press Connect.

That's it. When the two computers have found each other, you'll see "Name is now connected." at the bottom of the window. This can take a minute — or, if the other computer is off, however long until it's back on.

You can see how it's going any time in Connections ▸ Sync Settings…: pick your friend in the list on the left. Invites nobody has used yet are listed on the General page, with a Cancel Invite button each.

3. Choose what your friend can see

Nothing is shared until you say so. In Connections ▸ Sync Settings…, click your friend's name on the left. Below their connection status are two sections:

• Library — tick the artists, albums or songs your friend may ask for, or tick Share whole library for everything (including songs you add later).
• Playlists — tick the playlists to share, or Share all playlists. A shared playlist brings its songs along: they show up ticked and greyed in the Library section (hover one to see which playlist is holding it there).

Select All and Select None do what they say — and if you click one by accident, just press Cancel: nothing is saved until you press OK.

Want everyone to see the same thing? On the General page, tick Share the same selection with all friends and choose there instead.

Sharing something doesn't send it. Your friend only receives what they ask for.

4. Browse a friend's library and ask for songs

Once you have a friend, a small ▾ appears on the right end of the Library button:

Click the ▾ and pick your friend. The button turns light purple and shows their library's name — you're now looking at what they've shared with you:

It works just like your own library, except nothing plays (the songs aren't on your computer yet). Instead, every artist, album and song has a little cassette button:

Button	What it means
	Not asked for. Click it to ask your friend for this.
	Asked for — this song is on its way to you. Click again to change your mind.
	Some of this artist's or album's songs are asked for. Click to ask for all of them.

Pressing the button on an artist or album asks for every song under it.

Along the bottom of the window:

• Hide tracks I have hides songs you already own. Songs that are probably the same as one of yours (same artist and title, different album or length) stay visible in light grey so you can decide.
• The size of what you've asked for, next to your free space. It turns orange if it would leave so little space that Syncthing pauses, and red if it won't fit at all.
• Save and Close sends your list to your friend and takes you back to your own library. Cancel forgets the changes. (Leaving any other way with changes asks "Save changes?" first.)

The songs you asked for arrive in your library by themselves, filed by artist and album like anything you'd add yourself, with "3 songs arrived from Sam." at the bottom of the window. They come with their names, album info and artwork — but not your friend's play counts or ratings.

5. Follow a friend's playlist

In a friend's library, their shared playlists are listed on the left, each with a UFO. Click a playlist's UFO to follow it:

Icon	What it means
	Not following. Click the UFO to follow this playlist.
	Following. Click again to stop.

Press Save and Close, and the playlist appears in your sidebar with a purple UFO, and plays like any other playlist:

• Songs that are still on their way show in grey; they become playable as they arrive. The bottom of the window says when your friend's folder last synced.
• A followed playlist's songs are kept separate from your library — you get to listen without them filling up your collection. Like one? Right-click the column headings, turn on Cassette, and press its cassette button to add it to your library.
• Right-click a followed playlist in the sidebar and choose Unfollow to let it go (its songs are cleaned up afterwards).

Two choices per friend, in Sync Settings on their page:

• Show followed playlists mixed in with yours, or grouped in a folder with their name.
• Keep their songs separate (the default), or add them to your library automatically.

If something isn't working

Sync Settings always says what's going on in plain words and what to do next. The common ones:

• "Syncthing isn't running" — run systemctl --user start syncthing, then press Retry on the General page.
• "Can't reach Syncthing's API" — press Read from Syncthing on the General page. (Or copy the key from Syncthing's page at http://127.0.0.1:8384: Actions ▸ Settings ▸ General ▸ API Key.)
• "Waiting for Name's computer" for a long time — both computers need to be on with Syncthing running, and your friend needs to have opened LinTunes once since you pasted the code. If it never connects, the code may already have been used: ask for a new one.
• "That code isn't valid" — part of the code got lost when it was copied. It's one long line starting with LTC1.; ask your friend to send it again.
• "This invite has already been used" — codes work once. Ask for a new one.

To stop sharing with someone, open their page in Sync Settings and press Remove Friend…. Songs you already brought into your library stay.