Read and store flac metadata

db/schema.sql

@@ -8,13 +8,32 @@ CREATE TABLE items (
 );
 
 CREATE TABLE music_metadata (
-    inode           BIGINT PRIMARY KEY REFERENCES items(inode) ON DELETE CASCADE,
-    track_title     TEXT NOT NULL,
-    album           TEXT NOT NULL,
-    track_number    INTEGER NOT NULL
+    inode               BIGINT PRIMARY KEY REFERENCES items(inode) ON DELETE CASCADE,
+    track_title         TEXT NOT NULL,
+    album               TEXT NOT NULL,
+    track_number        INTEGER NOT NULL,
+    header              BYTEA NOT NULL,
+    real_audio_start    BIGINT NOT NULL
 );
 
 CREATE TABLE music_metadata_artists (
-    inode           BIGINT NOT NULL REFERENCES music_metadata(inode) ON DELETE CASCADE,
-    artist          TEXT NOT NULL
+    inode   BIGINT NOT NULL REFERENCES music_metadata(inode) ON DELETE CASCADE,
+    artist  TEXT NOT NULL,
+    PRIMARY KEY (inode, artist)
+);
+
+CREATE TABLE music_metadata_other_tags (
+    inode       BIGINT NOT NULL REFERENCES music_metadata(inode) ON DELETE CASCADE,
+    position    INTEGER NOT NULL,
+    tag         TEXT NOT NULL,
+    PRIMARY KEY (inode, position)
+);
+
+CREATE TABLE music_metadata_pictures (
+    inode           BIGINT NOT NULL REFERENCES music_metadata(inode) ON DELETE CASCADE,
+    position        INTEGER NOT NULL,
+    block_header    BYTEA NOT NULL,
+    data_offset     BIGINT NOT NULL,
+    data_length     BIGINT NOT NULL,
+    PRIMARY KEY (inode, position)
 );

devenv.nix

@@ -27,6 +27,7 @@
   packages = with pkgs; [
     git
     just
+    flac
 
     opencode
   ];

src/local.rs

@@ -1,8 +1,8 @@
 use std::{
     collections::BTreeMap,
     fs,
-    hash::{Hash, Hasher},
-    io,
+    hash::Hasher,
+    io::{self, Read, Seek, SeekFrom},
     os::unix::{
         ffi::OsStrExt,
         fs::{MetadataExt, PermissionsExt},
@@ -18,8 +18,11 @@ use notify::{Event, EventKind, RecursiveMode, Watcher};
 use sea_orm::entity::prelude::*;
 use twox_hash::XxHash64;
 
+use crate::file_watcher::FileWatcher;
 use crate::music_metadata::MusicMetadata;
-use crate::{file_watcher::FileWatcher, music_metadata};
+use crate::music_metadata::db::{
+    artists, music_metadata as music_metadata_entity, other_tags, pictures,
+};
 
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 enum FileType {
@@ -109,13 +112,22 @@ impl LocalOrigin {
         let mut to_insert: Vec<ActiveModel> = vec![];
         let mut to_update: Vec<ActiveModel> = vec![];
         let mut to_delete: Vec<i64> = vec![];
+        let mut to_save_music: Vec<i64> = vec![];
 
         for (ino, item) in &snapshot {
             let ino_i64 = ino.0 as i64;
             match db_items.get(&ino_i64) {
-                None => to_insert.push(ActiveModel::from(item)),
+                None => {
+                    to_insert.push(ActiveModel::from(item));
+                    if item.music_metadata.is_some() {
+                        to_save_music.push(ino_i64);
+                    }
+                }
                 Some(db_item) if db_item.hash != item.hash as i64 => {
-                    to_update.push(ActiveModel::from(item))
+                    to_update.push(ActiveModel::from(item));
+                    if item.music_metadata.is_some() {
+                        to_save_music.push(ino_i64);
+                    }
                 }
                 _ => {}
             }
@@ -137,6 +149,18 @@ impl LocalOrigin {
             Entity::delete_by_id(ino).exec(&client).await.unwrap();
         }
 
+        for ino_i64 in &to_save_music {
+            let ino = INodeNo(*ino_i64 as u64);
+            if let Some(music_metadata) = snapshot
+                .get(&ino)
+                .and_then(|item| item.music_metadata.as_ref())
+            {
+                LocalOrigin::save_music_metadata(*ino_i64, music_metadata, &client)
+                    .await
+                    .unwrap();
+            }
+        }
+
         // For unchanged items (hash matches), restore virtual paths from DB
         // so that renames performed in a previous session are preserved.
         let restorations: Vec<(INodeNo, String, PathBuf)> = db_items
@@ -177,6 +201,73 @@ impl LocalOrigin {
         Ok(local_origin)
     }
 
+    async fn save_music_metadata(
+        inode: i64,
+        music_metadata: &MusicMetadata,
+        client: &sea_orm::DatabaseConnection,
+    ) -> Result<(), sea_orm::DbErr> {
+        use sea_orm::ActiveValue::Set;
+
+        music_metadata_entity::Entity::delete_by_id(inode)
+            .exec(client)
+            .await?;
+
+        music_metadata_entity::Entity::insert(music_metadata_entity::ActiveModel {
+            inode: Set(inode),
+            track_title: Set(music_metadata.track_title.clone()),
+            album: Set(music_metadata.album.clone()),
+            track_number: Set(music_metadata.track_number),
+            header: Set(music_metadata.header.clone()),
+            real_audio_start: Set(music_metadata.real_audio_start as i64),
+        })
+        .exec(client)
+        .await?;
+
+        if !music_metadata.artist.is_empty() {
+            artists::Entity::insert_many(music_metadata.artist.iter().map(|a| {
+                artists::ActiveModel {
+                    inode: Set(inode),
+                    artist: Set(a.clone()),
+                }
+            }))
+            .exec(client)
+            .await?;
+        }
+
+        if !music_metadata.other_tags.is_empty() {
+            other_tags::Entity::insert_many(music_metadata.other_tags.iter().enumerate().map(
+                |(pos, tag)| other_tags::ActiveModel {
+                    inode: Set(inode),
+                    position: Set(pos as i32),
+                    tag: Set(tag.clone()),
+                },
+            ))
+            .exec(client)
+            .await?;
+        }
+
+        if !music_metadata.picture_block_headers.is_empty() {
+            pictures::Entity::insert_many(
+                music_metadata
+                    .picture_block_headers
+                    .iter()
+                    .zip(music_metadata.picture_data_ranges.iter())
+                    .enumerate()
+                    .map(|(pos, (hdr, (offset, len)))| pictures::ActiveModel {
+                        inode: Set(inode),
+                        position: Set(pos as i32),
+                        block_header: Set(hdr.to_vec()),
+                        data_offset: Set(*offset as i64),
+                        data_length: Set(*len as i64),
+                    }),
+            )
+            .exec(client)
+            .await?;
+        }
+
+        Ok(())
+    }
+
     fn fill_fileset(
         map: &Arc<Mutex<BTreeMap<INodeNo, LocalItem>>>,
         source: &Path,
@@ -293,9 +384,14 @@ impl LocalOrigin {
         let crtime = metadata.created().unwrap_or(SystemTime::UNIX_EPOCH);
         let kind = LocalOrigin::file_type(local_file.file_type);
 
+        let size = match &local_file.music_metadata {
+            Some(mm) if mm.real_audio_start > 0 => mm.virtual_size(metadata.size()),
+            _ => metadata.size(),
+        };
+
         return FileAttr {
             ino: local_file.inode,
-            size: metadata.size(),
+            size,
             blocks: metadata.blocks(),
             atime: atime,
             mtime: mtime,
@@ -319,6 +415,15 @@ impl LocalOrigin {
         };
     }
 
+    fn read_bytes_at(path: &Path, offset: u64, len: usize) -> io::Result<Vec<u8>> {
+        let mut f = fs::File::open(path)?;
+        f.seek(SeekFrom::Start(offset))?;
+        let mut buf = vec![0u8; len];
+        let n = f.read(&mut buf)?;
+        buf.truncate(n);
+        Ok(buf)
+    }
+
     fn parent_inode_from_path(local_path: &Path) -> INodeNo {
         let components: Vec<_> = local_path.components().collect();
         if components.len() <= 1 {
@@ -540,6 +645,121 @@ impl Filesystem for LocalOrigin {
         reply.ok();
     }
 
+    fn read(
+        &self,
+        _req: &Request,
+        ino: INodeNo,
+        _fh: fuser::FileHandle,
+        offset: u64,
+        size: u32,
+        _flags: fuser::OpenFlags,
+        _lock_owner: Option<fuser::LockOwner>,
+        reply: fuser::ReplyData,
+    ) {
+        let files = self.files.lock().unwrap();
+        let item = match files.get(&ino) {
+            Some(f) => f,
+            None => {
+                reply.error(Errno::ENOENT);
+                return;
+            }
+        };
+
+        let original_path = item.original_path.clone();
+        let mm = item
+            .music_metadata
+            .as_ref()
+            .filter(|mm| mm.real_audio_start > 0);
+        let is_flac = mm.is_some();
+        let header = mm.map(|mm| mm.header.clone()).unwrap_or_default();
+        let pic_hdrs = mm
+            .map(|mm| mm.picture_block_headers.clone())
+            .unwrap_or_default();
+        let pic_ranges = mm
+            .map(|mm| mm.picture_data_ranges.clone())
+            .unwrap_or_default();
+        let real_audio_start = mm.map(|mm| mm.real_audio_start).unwrap_or(0);
+        drop(files);
+
+        if !is_flac {
+            match LocalOrigin::read_bytes_at(&original_path, offset, size as usize) {
+                Ok(bytes) => reply.data(&bytes),
+                Err(_) => reply.error(Errno::EIO),
+            }
+            return;
+        }
+
+        let end = offset + size as u64;
+        let header_end = header.len() as u64;
+
+        // Pure header read — most common for tag readers
+        if end <= header_end {
+            reply.data(&header[offset as usize..end as usize]);
+            return;
+        }
+
+        // Multi-region read: walk [header][pic_hdr+pic_data]...[audio] and collect bytes
+        let mut buf = Vec::with_capacity(size as usize);
+
+        if offset < header_end {
+            buf.extend_from_slice(&header[offset as usize..]);
+        }
+
+        let mut virt_pos = header_end;
+        for (pic_hdr, (data_real_offset, data_len)) in pic_hdrs.iter().zip(pic_ranges.iter()) {
+            let pic_hdr_end = virt_pos + 4;
+            let pic_end = pic_hdr_end + data_len;
+
+            if end <= virt_pos {
+                break;
+            }
+            if offset >= pic_end {
+                virt_pos = pic_end;
+                continue;
+            }
+
+            let hdr_from = (offset.max(virt_pos) - virt_pos) as usize;
+            let hdr_to = ((end.min(pic_hdr_end)) - virt_pos) as usize;
+            if hdr_from < hdr_to {
+                buf.extend_from_slice(&pic_hdr[hdr_from..hdr_to.min(4)]);
+            }
+
+            let data_start = offset.max(pic_hdr_end);
+            let data_end = end.min(pic_end);
+            if data_start < data_end {
+                let real_off = data_real_offset + (data_start - pic_hdr_end);
+                match LocalOrigin::read_bytes_at(
+                    &original_path,
+                    real_off,
+                    (data_end - data_start) as usize,
+                ) {
+                    Ok(bytes) => buf.extend_from_slice(&bytes),
+                    Err(_) => {
+                        reply.error(Errno::EIO);
+                        return;
+                    }
+                }
+            }
+
+            virt_pos = pic_end;
+        }
+
+        let audio_start = offset.max(virt_pos);
+        if audio_start < end {
+            let real_off = real_audio_start + (audio_start - virt_pos);
+            match LocalOrigin::read_bytes_at(&original_path, real_off, (end - audio_start) as usize)
+            {
+                Ok(bytes) => buf.extend_from_slice(&bytes),
+                Err(_) => {
+                    reply.error(Errno::EIO);
+                    return;
+                }
+            }
+        }
+
+        reply.data(&buf);
+    }
+
     fn lookup(
         &self,
         _req: &Request,

src/main.rs

@@ -1,6 +1,5 @@
 use clap::Parser;
 use file_watcher::FileWatcher;
-use std::path::PathBuf;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::Duration;

src/music_metadata.rs

@@ -1,4 +1,8 @@
-use std::{fs, path::Path};
+use std::{
+    fs,
+    io::{Read, Seek, SeekFrom},
+    path::Path,
+};
 
 use symphonia::core::{
     formats::FormatOptions,
@@ -13,9 +17,23 @@ pub struct MusicMetadata {
     pub album: String,
     pub track_number: i32,
     pub track_title: String,
+    pub other_tags: Vec<String>,
+    pub header: Vec<u8>,
+    pub picture_block_headers: Vec<[u8; 4]>,
+    pub picture_data_ranges: Vec<(u64, u64)>,
+    pub real_audio_start: u64,
 }
 
 impl MusicMetadata {
+    pub fn virtual_size(&self, real_file_size: u64) -> u64 {
+        let pictures_size: u64 = self
+            .picture_data_ranges
+            .iter()
+            .map(|(_, len)| 4 + len)
+            .sum();
+        self.header.len() as u64 + pictures_size + (real_file_size - self.real_audio_start)
+    }
+
     pub fn parse_music_metadata(path: &Path) -> Option<MusicMetadata> {
         let src = fs::File::open(path).expect("failed to open media");
         let mss = MediaSourceStream::new(Box::new(src), Default::default());
@@ -32,25 +50,228 @@ impl MusicMetadata {
         let metadata: Metadata = format.format.metadata();
         let revision: &MetadataRevision = metadata.current().unwrap();
 
-        let mut music_metadata = MusicMetadata {
-            ..Default::default()
-        };
+        let mut music_metadata = MusicMetadata::default();
 
         for tag in revision.tags() {
-            let tag_type = tag.std_key.expect("no std_key for tag found");
             let value = tag.value.to_string();
-
-            match tag_type {
-                StandardTagKey::Artist => music_metadata.artist.push(value),
-                StandardTagKey::Album => music_metadata.album = value,
-                StandardTagKey::TrackNumber => {
-                    music_metadata.track_number = value.parse::<i32>().unwrap()
+            match tag.std_key {
+                Some(StandardTagKey::Artist) => music_metadata.artist.push(value),
+                Some(StandardTagKey::Album) => music_metadata.album = value,
+                Some(StandardTagKey::TrackNumber) => {
+                    music_metadata.track_number = value.parse::<i32>().unwrap_or(0)
                 }
-                StandardTagKey::TrackTitle => music_metadata.track_title = value,
-                _ => {}
+                Some(StandardTagKey::TrackTitle) => music_metadata.track_title = value,
+                _ => music_metadata
+                    .other_tags
+                    .push(format!("{}={}", tag.key, value)),
             }
         }
 
-        return Some(music_metadata);
+        if let Some(parsed) = parse_flac(path) {
+            music_metadata.real_audio_start = parsed.audio_start;
+            music_metadata.picture_block_headers = parsed.picture_block_headers;
+            music_metadata.picture_data_ranges = parsed.picture_data_ranges;
+            music_metadata.header = build_flac_header(parsed.other_blocks, &music_metadata);
+        }
+
+        Some(music_metadata)
     }
 }
+
+struct FlacParsed {
+    other_blocks: Vec<(u8, Vec<u8>)>,
+    picture_block_headers: Vec<[u8; 4]>,
+    picture_data_ranges: Vec<(u64, u64)>,
+    audio_start: u64,
+}
+
+fn parse_flac(path: &Path) -> Option<FlacParsed> {
+    let mut f = fs::File::open(path).ok()?;
+
+    let mut magic = [0u8; 4];
+    f.read_exact(&mut magic).ok()?;
+    if &magic != b"fLaC" {
+        return None;
+    }
+
+    let mut other_blocks: Vec<(u8, Vec<u8>)> = vec![];
+    let mut picture_block_headers: Vec<[u8; 4]> = vec![];
+    let mut picture_data_ranges: Vec<(u64, u64)> = vec![];
+    let mut pos = 4u64;
+
+    loop {
+        let mut hdr = [0u8; 4];
+        f.read_exact(&mut hdr).ok()?;
+        let is_last = (hdr[0] & 0x80) != 0;
+        let block_type = hdr[0] & 0x7f;
+        let length = u32::from_be_bytes([0, hdr[1], hdr[2], hdr[3]]) as u64;
+        pos += 4;
+
+        if block_type == 6 {
+            // PICTURE: keep block header (we'll fix is_last later), record data range
+            picture_block_headers.push(hdr);
+            picture_data_ranges.push((pos, length));
+            f.seek(SeekFrom::Current(length as i64)).ok()?;
+        } else {
+            let mut data = vec![0u8; length as usize];
+            f.read_exact(&mut data).ok()?;
+            // Skip VORBIS_COMMENT (type 4) — we rebuild it
+            if block_type != 4 {
+                other_blocks.push((block_type, data));
+            }
+        }
+
+        pos += length;
+        if is_last {
+            break;
+        }
+    }
+
+    // Fix is_last on the last picture block header: it must be 1 when audio follows
+    if let Some(last_hdr) = picture_block_headers.last_mut() {
+        last_hdr[0] = 0x80 | (last_hdr[0] & 0x7f);
+    }
+
+    Some(FlacParsed {
+        other_blocks,
+        picture_block_headers,
+        picture_data_ranges,
+        audio_start: pos,
+    })
+}
+
+fn build_flac_header(blocks: Vec<(u8, Vec<u8>)>, metadata: &MusicMetadata) -> Vec<u8> {
+    let vorbis = build_vorbis_comment(metadata);
+
+    let mut patched: Vec<(u8, Vec<u8>)> = blocks;
+    patched.push((4, vorbis));
+
+    let has_pictures = !metadata.picture_data_ranges.is_empty();
+    let mut out = Vec::new();
+    out.extend_from_slice(b"fLaC");
+
+    let last = patched.len() - 1;
+    for (i, (block_type, data)) in patched.iter().enumerate() {
+        // is_last only if this is the final block AND no picture blocks follow
+        let is_last_block = i == last && !has_pictures;
+        let flag: u8 = if is_last_block { 0x80 } else { 0x00 };
+        let length = data.len() as u32;
+        out.push(flag | block_type);
+        out.push((length >> 16) as u8);
+        out.push((length >> 8) as u8);
+        out.push(length as u8);
+        out.extend_from_slice(data);
+    }
+
+    out
+}
+
+pub mod db {
+    pub mod music_metadata {
+        use sea_orm::entity::prelude::*;
+
+        #[derive(Clone, Debug, PartialEq, Eq, DeriveEntityModel)]
+        #[sea_orm(table_name = "music_metadata")]
+        pub struct Model {
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub inode: i64,
+            pub track_title: String,
+            pub album: String,
+            pub track_number: i32,
+            #[sea_orm(column_type = "Blob")]
+            pub header: Vec<u8>,
+            pub real_audio_start: i64,
+        }
+
+        #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+        pub enum Relation {}
+
+        impl ActiveModelBehavior for ActiveModel {}
+    }
+
+    pub mod artists {
+        use sea_orm::entity::prelude::*;
+
+        #[derive(Clone, Debug, PartialEq, Eq, DeriveEntityModel)]
+        #[sea_orm(table_name = "music_metadata_artists")]
+        pub struct Model {
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub inode: i64,
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub artist: String,
+        }
+
+        #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+        pub enum Relation {}
+
+        impl ActiveModelBehavior for ActiveModel {}
+    }
+
+    pub mod other_tags {
+        use sea_orm::entity::prelude::*;
+
+        #[derive(Clone, Debug, PartialEq, Eq, DeriveEntityModel)]
+        #[sea_orm(table_name = "music_metadata_other_tags")]
+        pub struct Model {
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub inode: i64,
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub position: i32,
+            pub tag: String,
+        }
+
+        #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+        pub enum Relation {}
+
+        impl ActiveModelBehavior for ActiveModel {}
+    }
+
+    pub mod pictures {
+        use sea_orm::entity::prelude::*;
+
+        #[derive(Clone, Debug, PartialEq, Eq, DeriveEntityModel)]
+        #[sea_orm(table_name = "music_metadata_pictures")]
+        pub struct Model {
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub inode: i64,
+            #[sea_orm(primary_key, auto_increment = false)]
+            pub position: i32,
+            #[sea_orm(column_type = "Blob")]
+            pub block_header: Vec<u8>,
+            pub data_offset: i64,
+            pub data_length: i64,
+        }
+
+        #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+        pub enum Relation {}
+
+        impl ActiveModelBehavior for ActiveModel {}
+    }
+}
+
+fn build_vorbis_comment(metadata: &MusicMetadata) -> Vec<u8> {
+    let vendor = b"musicfs";
+    let mut out = Vec::new();
+
+    out.extend_from_slice(&(vendor.len() as u32).to_le_bytes());
+    out.extend_from_slice(vendor);
+
+    let mut comments: Vec<String> = vec![
+        format!("TITLE={}", metadata.track_title),
+        format!("ALBUM={}", metadata.album),
+        format!("TRACKNUMBER={}", metadata.track_number),
+    ];
+    for artist in &metadata.artist {
+        comments.push(format!("ARTIST={}", artist));
+    }
+    comments.extend(metadata.other_tags.iter().cloned());
+
+    out.extend_from_slice(&(comments.len() as u32).to_le_bytes());
+    for comment in &comments {
+        let bytes = comment.as_bytes();
+        out.extend_from_slice(&(bytes.len() as u32).to_le_bytes());
+        out.extend_from_slice(bytes);
+    }
+
+    out
+}