feat(users/Profpatsch/lyric): read lyric sqlite from squashfs

The unpacked lrclib dump is 40GB at this point, but compresses very
well (to about 10GB give or take). So I thought about how to store it
in a compressed on disk, but still allow sqlite to query
efficiently (i.e. use a compression format that has arbitrary seek
indices).

Squashfs! with zstd compression!

```
mksquashfs ~/.cache/lyric-bak/ \
  ~/tmp/squashtest \
  -comp zstd \
  -Xcompression-level 5
```

Still need to write a helper that does the download & compression for
me to update the database once in a blue moon.

Unfortunately, sqlite-utils does not allow URL connection strings yet,
so I had to do a horrible SQL interpolation bit.
Issue tracker: https://mastodon.xyz/@Profpatsch/114083481108799334

This also changes the query to filter out every track that has neither
plain nor synched lyrics (yeah those exist for some reason?).

Change-Id: Ief0519ae8d9e5f14b66f6df6e3bcecae911ea142
Reviewed-on: https://cl.tvl.fyi/c/depot/+/13208
Tested-by: BuildkiteCI
Reviewed-by: Profpatsch <mail@profpatsch.de>

users/Profpatsch/lyric/default.nix

@@ -1,7 +1,11 @@
 { pkgs, depot, lib, ... }:
 
 let
-  bins = depot.nix.getBins pkgs.sqlite-utils [ "sqlite-utils" ]
+  bins = depot.nix.getBins pkgs.sqlite [ "sqlite3" ]
+    // depot.nix.getBins pkgs.util-linux [ "unshare" ]
+    // depot.nix.getBins pkgs.coreutils [ "echo" ]
+    // depot.nix.getBins pkgs.gnused [ "sed" ]
+    // depot.nix.getBins pkgs.squashfuse [ "squashfuse" ]
     // depot.nix.getBins pkgs.jq [ "jq" ];
 
   mpv-script = pkgs.writeTextFile {
@@ -34,39 +38,89 @@ let
     "\${cache}/lyric/as-files/\${1}.lrc"
   ];
 
+  # looool
+  escapeSqliteString = depot.nix.writeExecline "escape-sqlite-string" { readNArgs = 1; } [
+    "pipeline"
+    [
+      "printf"
+      "%s"
+      "$1"
+    ]
+    bins.sed
+    "s/''/''''/g"
+  ];
+
   # Display lyrics for the given search string;
   # search string can contain a substring of band name, album name, song title
   #
   # Use the database dump from https://lrclib.net/db-dumps and place it in ~/.cache/lyric/lrclib-db-dump.sqlite3
+  #
+  # TODO: put in the nodejs argh
   lyric =
-
     (depot.nix.writeExecline "lyric" { readNArgs = 1; } [
       "backtick"
       "-E"
       "cache"
       [ depot.users.Profpatsch.xdg-cache-home ]
+      # make sure the squashfuse is only mounted while the command is running
+      bins.unshare
+      "--user"
+      "--mount"
+      "--pid"
+      "--map-root-user"
+      "--kill-child"
+      "if"
+      [ "mkdir" "-p" "\${cache}/lyric/dump" ]
+      # TODO: provide a command that takes an url of a lyric.gz and converts it to this here squash image
+      "if"
+      [ bins.squashfuse "-ononempty" "\${cache}/lyric/lyric-db.squash" "\${cache}/lyric/dump" ]
+      # please help me god
+      "backtick"
+      "-E"
+      "searchstring"
+      [ escapeSqliteString "$1" ]
       "pipeline"
       [
-        bins.sqlite-utils
+        "pipeline"
-        "query"
+        [
-        "\${cache}/lyric/lrclib-db-dump.sqlite3"
+          "echo"
-        ''
+          (''
-          select
+            .mode json
-              synced_lyrics,
+            select * from (
-              has_synced_lyrics,
+              -- first we try to find if we can find the track verbatim
-              plain_lyrics
+              select * from (select
-          from
+                  synced_lyrics,
-              tracks_fts(:searchstring) tf
+                  has_synced_lyrics,
-              join tracks t on t.rowid = tf.rowid
+                  plain_lyrics
-              join lyrics l on t.rowid = l.track_id
+              from
-          order by
+                  tracks_fts('' + "'\${searchstring}'" + '') tf
-              has_synced_lyrics desc, t.id
+                join tracks t on t.rowid = tf.rowid
+                join lyrics l on t.rowid = l.track_id
+            order by
+                has_synced_lyrics desc, t.id
+            )
+            UNION
+            select * from (select
+                synced_lyrics,
+                has_synced_lyrics,
+                plain_lyrics
+            from
+                tracks_fts('' + "'\${searchstring}'" + '') tf
+                join tracks t on t.rowid = tf.rowid
+                join lyrics l on t.rowid = l.track_id
+            order by
+                has_synced_lyrics desc, t.id
+            )
+          )
+          where synced_lyrics is not null and synced_lyrics != ''''
+          and plain_lyrics is not null and plain_lyrics != ''''
           limit
-              1
+              1;
         ''
-        "--param"
+          )
-        "searchstring"
+        ]
-        "$1"
+        bins.sqlite3
+        "file:\${cache}/lyric/dump/lrclib-db-dump.sqlite3?immutable=1"
       ]
       bins.jq
       "-r"
@@ -84,9 +138,12 @@ let
     ]);
 
 
+  js = depot.users.Profpatsch.napalm.buildPackage ./. { };
+
 in
 {
   inherit
     lyric
+    js
     mpv-script;
 }