Add per-photo rotate-left/right widget to admin edit pageHEADmain

Many older photos (especially pre-EXIF-orientation cameras) are off
by a multiple of 90 degrees with no metadata to auto-correct. Each
image row in the admin file table now has rotate buttons that
physically rotate the file (auto-orienting first to normalize any
existing EXIF tag), swap the stored width/height, and clear the
cached thumbnail so it regenerates from the corrected image.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/app.rb b/app.rb
index c5f533b..a977455 100644
--- a/app.rb
+++ b/app.rb
@@ -702,6 +702,43 @@ def save_edits(rel, dir)
   atomic_write(File.join(dir, 'album.json'), JSON.pretty_generate(data))
 end
 
+post '/admin/rotate/' do
+  require_admin!
+  rotate_file('', MEDIA_ROOT)
+end
+
+post '/admin/rotate/*' do
+  require_admin!
+  rel = params[:splat].first.chomp('/')
+  rotate_file(rel, resolve_dir(rel))
+end
+
+def rotate_file(rel, dir)
+  name = File.basename(params[:file].to_s)
+  full = File.join(dir, name)
+  halt 404 unless File.file?(full)
+  halt 400 unless IMAGE_EXTS.include?(File.extname(name).downcase.delete_prefix('.'))
+
+  degrees = params[:dir] == 'left' ? -90 : 90
+  img = MiniMagick::Image.open(full)
+  img.combine_options do |c|
+    c.auto_orient
+    c.rotate degrees
+  end
+  img.write(full)
+
+  data = load_album(dir)
+  data['files'] ||= {}
+  meta = (data['files'][name] ||= {})
+  meta['width'], meta['height'] = meta['height'], meta['width'] if meta['width'] && meta['height']
+  atomic_write(File.join(dir, 'album.json'), JSON.pretty_generate(data))
+
+  thumb = thumb_cache_path(rel.empty? ? name : "#{rel}/#{name}")
+  File.unlink(thumb) if File.exist?(thumb)
+
+  redirect "/admin/edit/#{rel}"
+end
+
 # ── Background update ─────────────────────────────────────────────────────────
 
 post '/admin/update' do