fix alignment of tables

maple-rs/src/db.rs

@@ -64,16 +64,21 @@ impl Database {
     // }
 
     pub fn export(self, path: &Path) -> std::io::Result<()> {
-        // 1) Reserve header page
         let mut f = File::create(path)?;
-        f.write_all(&vec![0u8; PAGE_SIZE as usize])?;
+        // reserve the file header space
+        // tables begin at 28
+        f.write_all(&vec![0u8; 28 as usize])?;
 
-        let (table, pages) = Table::from_rows(PageType::Tracks, 1, PAGE_SIZE, self.tracks.values().cloned().take(1).map(Row::Track)).unwrap();
+        // tables start here
+        let (tracks, tracks_pages) = Table::from_rows(PageType::Tracks, 1, PAGE_SIZE, self.tracks.values().cloned().take(2).map(Row::Track)).unwrap();
+        // f.seek(SeekFrom::Start(0x1c)).unwrap();
+        println!("Writing table at {:?}", f.stream_position());
+        tracks.write_le(&mut f).unwrap();
 
-        println!("{:?}", table);
-        println!("{:?}", pages);
-        table.write_le(&mut f).unwrap();
-        pages.write_le_args(&mut f, (PAGE_SIZE.into(),)).unwrap();
+        f.seek(SeekFrom::Start(4096)).unwrap();
+        println!("Writing tracks_pages at {:?}", f.stream_position());
+        tracks_pages.write_le_args(&mut f, (PAGE_SIZE.into(),)).unwrap();
+        println!("{:?}", f.stream_position());
 
         // page is somehow getting zeroed when ... writing? reading??
         // validate it by writing and reading it back
@@ -100,9 +105,9 @@ impl Database {
         let header = Header {
             // fill other required fields in your crate
             sequence: 0, // or previous+1
-            next_unused_page: PageIndex(pages.len() as u32 + 1),
+            next_unused_page: PageIndex(tracks_pages.len() as u32 + 1),
             tables: vec![
-                table,
+                tracks,
                 // Table { page_type: PageType::PlaylistTree,    first_page: PageIndex(tree_first),    last_page: PageIndex(tree_last),    empty_candidate: 0, /* … */ },
                 // Table { page_type: PageType::PlaylistEntries, first_page: PageIndex(entries_first), last_page: PageIndex(entries_last), empty_candidate: 0, /* … */ },
                 // Table { page_type: PageType::Artwork,         first_page: PageIndex(art_first),     last_page: PageIndex(art_last),     empty_candidate: 0, /* … */ },
@@ -110,14 +115,10 @@ impl Database {
             ..Default::default()
         };
 
-        // Write header at offset 0 and pad to one page
         f.seek(SeekFrom::Start(0))?;
+        println!("Writing header at {:?}", f.stream_position());
         header.write_le(&mut f).unwrap();
-        // pad residual of page 0 if BinWrite didn’t fill it:
-        let pos = f.stream_position()?;
-        if pos < PAGE_SIZE as u64 {
-            f.write_all(&vec![0u8; (PAGE_SIZE as u64 - pos) as usize])?;
-        }
+
         Ok(())
     }