From 0667f01471f8f1032f778e90bfee09af42e63ed9 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 02:01:43 +0900
Subject: [PATCH 01/39] Measure scan only

---
 src/library/library.cr | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 9351e60..32cc161 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -98,6 +98,7 @@ class Library
   end
 
   def scan
+    start = Time.local
     unless Dir.exists? @dir
       Logger.info "The library directory #{@dir} does not exist. " \
                   "Attempting to create it"
@@ -122,7 +123,8 @@ class Library
     storage.bulk_insert_ids
     storage.close
 
-    Logger.debug "Scan completed"
+    ms = (Time.local - start).total_milliseconds
+    Logger.debug "Scan completed. #{ms}ms"
     Storage.default.mark_unavailable
   end
 

From 291a340cdd48b068e71cde78b9cf22227658ecf6 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Thu, 9 Sep 2021 20:45:47 +0900
Subject: [PATCH 02/39] Add yaml serializer to Library, Title, Entry

---
 src/library/entry.cr   | 2 ++
 src/library/library.cr | 2 ++
 src/library/title.cr   | 2 ++
 3 files changed, 6 insertions(+)

diff --git a/src/library/entry.cr b/src/library/entry.cr
index 28b7122..bb0aa1b 100644
--- a/src/library/entry.cr
+++ b/src/library/entry.cr
@@ -1,6 +1,8 @@
 require "image_size"
 
 class Entry
+  include YAML::Serializable
+
   getter zip_path : String, book : Title, title : String,
     size : String, pages : Int32, id : String, encoded_path : String,
     encoded_title : String, mtime : Time, err_msg : String?
diff --git a/src/library/library.cr b/src/library/library.cr
index 32cc161..9c23d68 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -1,4 +1,6 @@
 class Library
+  include YAML::Serializable
+
   getter dir : String, title_ids : Array(String),
     title_hash : Hash(String, Title)
 
diff --git a/src/library/title.cr b/src/library/title.cr
index f1915d4..899e21f 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -2,6 +2,8 @@ require "digest"
 require "../archive"
 
 class Title
+  include YAML::Serializable
+
   getter dir : String, parent_id : String, title_ids : Array(String),
     entries : Array(Entry), title : String, id : String,
     encoded_title : String, mtime : Time, signature : UInt64,

From 4409ed8f455d9e44705974ca1896e884a5957fc2 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Thu, 9 Sep 2021 21:14:11 +0900
Subject: [PATCH 03/39] Implement save_instance, load_instance

---
 src/library/library.cr | 37 +++++++++++++++++++++++++++++++++++++
 src/mango.cr           |  1 +
 2 files changed, 38 insertions(+)

diff --git a/src/library/library.cr b/src/library/library.cr
index 9c23d68..b8528f3 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -6,6 +6,41 @@ class Library
 
   use_default
 
+  def save_instance
+    path = Config.current.library_path
+    instance_file_path = File.join path, "library.yml.zip"
+
+    writer = Compress::Zip::Writer.new instance_file_path
+    writer.add "instance.yml", self.to_yaml
+    writer.close
+  end
+
+  def self.load_instance
+    dir = Config.current.library_path
+    return unless Dir.exists? dir
+    instance_file_path = File.join path, "library.yml.zip"
+    return unless File.exists? instance_file_path
+
+    zip_file = Compress::Zip::File.new instance_file_path
+    instance_file = zip_file.entries.find { |entry| entry.filename == "instance.yml" }
+
+    if instance_file.nil?
+      zip_file.close
+      return
+    end
+    begin
+      instance_file.open do |content|
+        @@default = Library.from_yaml content
+      end
+    rescue e
+      Logger.error e
+    end
+
+    zip_file.close
+
+    scan
+  end
+
   def initialize
     register_mime_types
 
@@ -128,6 +163,8 @@ class Library
     ms = (Time.local - start).total_milliseconds
     Logger.debug "Scan completed. #{ms}ms"
     Storage.default.mark_unavailable
+
+    save_instance
   end
 
   def get_continue_reading_entries(username)
diff --git a/src/mango.cr b/src/mango.cr
index f27165e..39b1352 100644
--- a/src/mango.cr
+++ b/src/mango.cr
@@ -58,6 +58,7 @@ class CLI < Clim
       LRUCache.init
       Storage.default
       Queue.default
+      Library.load_instance
       Library.default
       Plugin::Downloader.default
 

From 0a90e3b3334d2be89d6517b8e576db7a546b9f34 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Fri, 10 Sep 2021 20:24:54 +0900
Subject: [PATCH 04/39] Ignore caches

---
 src/library/library.cr | 4 ++--
 src/library/title.cr   | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index b8528f3..a3f2baa 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -18,7 +18,7 @@ class Library
   def self.load_instance
     dir = Config.current.library_path
     return unless Dir.exists? dir
-    instance_file_path = File.join path, "library.yml.zip"
+    instance_file_path = File.join dir, "library.yml.zip"
     return unless File.exists? instance_file_path
 
     zip_file = Compress::Zip::File.new instance_file_path
@@ -38,7 +38,7 @@ class Library
 
     zip_file.close
 
-    scan
+    Library.default.scan
   end
 
   def initialize
diff --git a/src/library/title.cr b/src/library/title.cr
index 899e21f..6c873b8 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -10,9 +10,13 @@ class Title
     entry_cover_url_cache : Hash(String, String)?
   setter entry_cover_url_cache : Hash(String, String)?
 
+  @[YAML::Field(ignore: true)]
   @entry_display_name_cache : Hash(String, String)?
+  @[YAML::Field(ignore: true)]
   @entry_cover_url_cache : Hash(String, String)?
+  @[YAML::Field(ignore: true)]
   @cached_display_name : String?
+  @[YAML::Field(ignore: true)]
   @cached_cover_url : String?
 
   def initialize(@dir : String, @parent_id)

From eb3e37b95097abf11b91c2a1c210fd71e0890126 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sat, 11 Sep 2021 13:30:07 +0900
Subject: [PATCH 05/39] Examine titles and recycle them

---
 src/library/library.cr | 8 +++++++-
 src/library/title.cr   | 6 ++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index a3f2baa..86375be 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -144,14 +144,20 @@ class Library
 
     storage = Storage.new auto_close: false
 
+    @title_ids.select! do |title_id|
+      title = @title_hash[title_id]
+      title.examine
+    end
+    remained_title_dirs = @title_ids.map { |id| title_hash[id].dir }
+
     (Dir.entries @dir)
       .select { |fn| !fn.starts_with? "." }
       .map { |fn| File.join @dir, fn }
+      .select { |path| !(remained_title_dirs.includes? path) }
       .select { |path| File.directory? path }
       .map { |path| Title.new path, "" }
       .select { |title| !(title.entries.empty? && title.titles.empty?) }
       .sort! { |a, b| a.title <=> b.title }
-      .tap { |_| @title_ids.clear }
       .each do |title|
         @title_hash[title.id] = title
         @title_ids << title.id
diff --git a/src/library/title.cr b/src/library/title.cr
index 6c873b8..44464c9 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -69,6 +69,12 @@ class Title
     end
   end
 
+  def examine : Bool
+    return false unless Dir.exists? @dir
+    signature = Dir.signature @dir
+    return @signature == signature
+  end
+
   def to_slim_json : String
     JSON.build do |json|
       json.object do

From fb43abb950137416043d0b923a75a10a073c395c Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sat, 11 Sep 2021 21:16:33 +0900
Subject: [PATCH 06/39] Enhance the examine method

---
 src/library/title.cr | 66 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 64 insertions(+), 2 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 44464c9..51b82c9 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -70,9 +70,71 @@ class Title
   end
 
   def examine : Bool
-    return false unless Dir.exists? @dir
+    return false unless Dir.exists? @dir # no title, should be removed
     signature = Dir.signature @dir
-    return @signature == signature
+    # `signature` doesn't reflect movings, renames in nested titles
+    # return true if @signature == signature # not changed, preserve
+
+    # fix title
+    @signature = signature
+    storage = Storage.default
+    id = storage.get_title_id dir, signature
+    if id.nil?
+      id = random_str
+      storage.insert_title_id({
+        path:      dir,
+        id:        id,
+        signature: signature.to_s,
+      })
+    end
+    @id = id
+    @mtime = File.info(@dir).modification_time
+
+    @title_ids.select! do |title_id|
+      title = Library.default.get_title! title_id
+      title.examine
+    end
+    remained_title_dirs = @title_ids.map do |id|
+      title = Library.default.get_title! id
+      title.dir
+    end
+
+    @entries.select! { |entry| File.exists? entry.zip_path }
+    remained_entry_zip_paths = @entries.map &.zip_path
+
+    Dir.entries(dir).each do |fn|
+      next if fn.starts_with? "."
+      path = File.join dir, fn
+      if File.directory? path
+        next if remained_title_dirs.includes? path
+        title = Title.new path, @id
+        next if title.entries.size == 0 && title.titles.size == 0
+        Library.default.title_hash[title.id] = title
+        @title_ids << title.id
+        next
+      end
+      if is_supported_file path
+        next if remained_entry_zip_paths.includes? path
+        entry = Entry.new path, self
+        @entries << entry if entry.pages > 0 || entry.err_msg
+      end
+    end
+
+    mtimes = [@mtime]
+    mtimes += @title_ids.map { |e| Library.default.title_hash[e].mtime }
+    mtimes += @entries.map &.mtime
+    @mtime = mtimes.max
+
+    @title_ids.sort! do |a, b|
+      compare_numerically Library.default.title_hash[a].title,
+        Library.default.title_hash[b].title
+    end
+    sorter = ChapterSorter.new @entries.map &.title
+    @entries.sort! do |a, b|
+      sorter.compare a.title, b.title
+    end
+
+    return true # this could be recycled
   end
 
   def to_slim_json : String

From 80e13abc4a9d5dd53346e58aaf72b0a94a9230b4 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sat, 11 Sep 2021 22:44:17 +0900
Subject: [PATCH 07/39] Spawn scan job

---
 src/library/library.cr | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 86375be..9ee26d1 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -21,6 +21,7 @@ class Library
     instance_file_path = File.join dir, "library.yml.zip"
     return unless File.exists? instance_file_path
 
+    Logger.debug "Load library instance"
     zip_file = Compress::Zip::File.new instance_file_path
     instance_file = zip_file.entries.find { |entry| entry.filename == "instance.yml" }
 
@@ -38,7 +39,13 @@ class Library
 
     zip_file.close
 
-    Library.default.scan
+    spawn do
+      start = Time.local
+      Library.default.scan
+      ms = (Time.local - start).total_milliseconds
+      Logger.info "Re-scanned #{Library.default.title_ids.size} titles \
+        in #{ms}ms"
+    end
   end
 
   def initialize

From e6214ddc5d0a752ed4abaaa268090235b27c1450 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 01:26:02 +0900
Subject: [PATCH 08/39] Rescan only if instance loaded

---
 src/library/library.cr | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 9ee26d1..15674cf 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -29,22 +29,26 @@ class Library
       zip_file.close
       return
     end
+    is_loaded = false
     begin
       instance_file.open do |content|
         @@default = Library.from_yaml content
       end
+      is_loaded = true
     rescue e
       Logger.error e
     end
 
     zip_file.close
 
-    spawn do
-      start = Time.local
-      Library.default.scan
-      ms = (Time.local - start).total_milliseconds
-      Logger.info "Re-scanned #{Library.default.title_ids.size} titles \
-        in #{ms}ms"
+    if is_loaded
+      spawn do
+        start = Time.local
+        Library.default.scan
+        ms = (Time.local - start).total_milliseconds
+        Logger.info "Re-scanned #{Library.default.title_ids.size} titles \
+          in #{ms}ms"
+      end
     end
   end
 

From 4e8b561f70111c33a280dfa6487a382fd8fdec24 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 00:37:48 +0900
Subject: [PATCH 09/39] Apply contents signature of directories

---
 src/library/title.cr  | 10 ++++++----
 src/util/signature.cr | 23 +++++++++++++++++++++++
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 51b82c9..5caefa0 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -32,6 +32,7 @@ class Title
       })
     end
     @id = id
+    @contents_signature = Dir.contents_signature dir
     @title = File.basename dir
     @encoded_title = URI.encode @title
     @title_ids = [] of String
@@ -71,12 +72,13 @@ class Title
 
   def examine : Bool
     return false unless Dir.exists? @dir # no title, should be removed
-    signature = Dir.signature @dir
-    # `signature` doesn't reflect movings, renames in nested titles
-    # return true if @signature == signature # not changed, preserve
+    contents_signature = Dir.contents_signature @dir
+    # not changed, preserve
+    return true if @contents_signature == contents_signature
 
     # fix title
-    @signature = signature
+    @contents_signature = contents_signature
+    @signature = Dir.signature @dir
     storage = Storage.default
     id = storage.get_title_id dir, signature
     if id.nil?
diff --git a/src/util/signature.cr b/src/util/signature.cr
index d1a0040..f2bf103 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -48,4 +48,27 @@ class Dir
     end
     Digest::CRC32.checksum(signatures.sort.join).to_u64
   end
+
+  # Returns the contents signature of the directory at dirname for checking
+  #   to rescan.
+  # Rescan conditions:
+  #   - When a file added, moved, removed, renamed (including which in nested
+  #       directories)
+  def self.contents_signature(dirname) : String
+    signatures = [] of String
+    self.open dirname do |dir|
+      dir.entries.sort.each do |fn|
+        next if fn.starts_with? "."
+        path = File.join dirname, fn
+        if File.directory? path
+          signatures << Dir.contents_signature path
+        else
+          # Only add its signature value to `signatures` when it is a
+          #   supported file
+          signatures << fn if is_supported_file fn
+        end
+      end
+    end
+    Digest::SHA1.hexdigest(signatures.sort.join)
+  end
 end

From a8f729f5c1021b2accfa15748f85f2f114181d61 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 00:48:23 +0900
Subject: [PATCH 10/39] Sort entries and titles when they needed

---
 src/library/title.cr | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 5caefa0..8260be9 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -92,6 +92,7 @@ class Title
     @id = id
     @mtime = File.info(@dir).modification_time
 
+    previous_titles_size = @title_ids.size
     @title_ids.select! do |title_id|
       title = Library.default.get_title! title_id
       title.examine
@@ -101,9 +102,12 @@ class Title
       title.dir
     end
 
+    previous_entries_size = @entries.size
     @entries.select! { |entry| File.exists? entry.zip_path }
     remained_entry_zip_paths = @entries.map &.zip_path
 
+    is_titles_added = false
+    is_entries_added = false
     Dir.entries(dir).each do |fn|
       next if fn.starts_with? "."
       path = File.join dir, fn
@@ -113,12 +117,16 @@ class Title
         next if title.entries.size == 0 && title.titles.size == 0
         Library.default.title_hash[title.id] = title
         @title_ids << title.id
+        is_titles_added = true
         next
       end
       if is_supported_file path
         next if remained_entry_zip_paths.includes? path
         entry = Entry.new path, self
-        @entries << entry if entry.pages > 0 || entry.err_msg
+        if entry.pages > 0 || entry.err_msg
+          @entries << entry
+          is_entries_added = true
+        end
       end
     end
 
@@ -127,13 +135,17 @@ class Title
     mtimes += @entries.map &.mtime
     @mtime = mtimes.max
 
-    @title_ids.sort! do |a, b|
-      compare_numerically Library.default.title_hash[a].title,
-        Library.default.title_hash[b].title
+    if is_titles_added || previous_titles_size != @title_ids.size
+      @title_ids.sort! do |a, b|
+        compare_numerically Library.default.title_hash[a].title,
+          Library.default.title_hash[b].title
+      end
     end
-    sorter = ChapterSorter.new @entries.map &.title
-    @entries.sort! do |a, b|
-      sorter.compare a.title, b.title
+    if is_entries_added || previous_entries_size != @entries.size
+      sorter = ChapterSorter.new @entries.map &.title
+      @entries.sort! do |a, b|
+        sorter.compare a.title, b.title
+      end
     end
 
     return true # this could be recycled

From 9309f51df634ae3a9f498c30ed31f0f8066dec6f Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 02:03:54 +0900
Subject: [PATCH 11/39] Memoization on dir contents_signature

---
 src/library/title.cr  | 7 ++++---
 src/util/signature.cr | 7 +++++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 8260be9..2e9db26 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -70,11 +70,12 @@ class Title
     end
   end
 
-  def examine : Bool
+  def examine(cache = {} of String => String) : Bool
     return false unless Dir.exists? @dir # no title, should be removed
-    contents_signature = Dir.contents_signature @dir
+    contents_signature = Dir.contents_signature @dir, cache
     # not changed, preserve
     return true if @contents_signature == contents_signature
+    puts "Contents changed in #{@dir}"
 
     # fix title
     @contents_signature = contents_signature
@@ -95,7 +96,7 @@ class Title
     previous_titles_size = @title_ids.size
     @title_ids.select! do |title_id|
       title = Library.default.get_title! title_id
-      title.examine
+      title.examine cache
     end
     remained_title_dirs = @title_ids.map do |id|
       title = Library.default.get_title! id
diff --git a/src/util/signature.cr b/src/util/signature.cr
index f2bf103..e56aa06 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -54,7 +54,8 @@ class Dir
   # Rescan conditions:
   #   - When a file added, moved, removed, renamed (including which in nested
   #       directories)
-  def self.contents_signature(dirname) : String
+  def self.contents_signature(dirname, cache = {} of String => String) : String
+    return cache[dirname] if cache[dirname]?
     signatures = [] of String
     self.open dirname do |dir|
       dir.entries.sort.each do |fn|
@@ -69,6 +70,8 @@ class Dir
         end
       end
     end
-    Digest::SHA1.hexdigest(signatures.sort.join)
+    hash = Digest::SHA1.hexdigest(signatures.sort.join)
+    cache[dirname] = hash
+    hash
   end
 end

From 7e36c91ea7000606aac0ca050a25d0cdb14871d7 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 10:47:15 +0900
Subject: [PATCH 12/39] Remove debug print

---
 src/library/title.cr | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 2e9db26..46de5b9 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -75,7 +75,6 @@ class Title
     contents_signature = Dir.contents_signature @dir, cache
     # not changed, preserve
     return true if @contents_signature == contents_signature
-    puts "Contents changed in #{@dir}"
 
     # fix title
     @contents_signature = contents_signature

From bdbdf9c94be29c62bf425c5f2349905b5c93c162 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 11:09:48 +0900
Subject: [PATCH 13/39] Fix to pass 'make check', fix comments

---
 src/library/library.cr |  4 +++-
 src/library/title.cr   | 12 ++++++------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 15674cf..4764b59 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -23,7 +23,9 @@ class Library
 
     Logger.debug "Load library instance"
     zip_file = Compress::Zip::File.new instance_file_path
-    instance_file = zip_file.entries.find { |entry| entry.filename == "instance.yml" }
+    instance_file = zip_file.entries.find do |entry|
+      entry.filename == "instance.yml"
+    end
 
     if instance_file.nil?
       zip_file.close
diff --git a/src/library/title.cr b/src/library/title.cr
index 46de5b9..ed63471 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -71,12 +71,12 @@ class Title
   end
 
   def examine(cache = {} of String => String) : Bool
-    return false unless Dir.exists? @dir # no title, should be removed
+    return false unless Dir.exists? @dir # No title, Remove this
     contents_signature = Dir.contents_signature @dir, cache
-    # not changed, preserve
+    # Not changed. Reuse this
     return true if @contents_signature == contents_signature
 
-    # fix title
+    # Fix title
     @contents_signature = contents_signature
     @signature = Dir.signature @dir
     storage = Storage.default
@@ -97,8 +97,8 @@ class Title
       title = Library.default.get_title! title_id
       title.examine cache
     end
-    remained_title_dirs = @title_ids.map do |id|
-      title = Library.default.get_title! id
+    remained_title_dirs = @title_ids.map do |title_id|
+      title = Library.default.get_title! title_id
       title.dir
     end
 
@@ -148,7 +148,7 @@ class Title
       end
     end
 
-    return true # this could be recycled
+    true # Fixed, reuse this
   end
 
   def to_slim_json : String

From cd48b45f110740b1348dcbf0369caf9d9909a7db Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 12:45:24 +0900
Subject: [PATCH 14/39] Add 'require "yaml"'

---
 src/library/entry.cr | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/library/entry.cr b/src/library/entry.cr
index bb0aa1b..5694551 100644
--- a/src/library/entry.cr
+++ b/src/library/entry.cr
@@ -1,4 +1,5 @@
 require "image_size"
+require "yaml"
 
 class Entry
   include YAML::Serializable

From 8c90b46114f637155f2b2f9efcc651092c2ef3eb Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 13:39:28 +0900
Subject: [PATCH 15/39] Remove removed titles from title_hash

---
 src/library/library.cr | 4 +++-
 src/library/title.cr   | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 4764b59..a7b43e9 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -159,7 +159,9 @@ class Library
 
     @title_ids.select! do |title_id|
       title = @title_hash[title_id]
-      title.examine
+      existence = title.examine
+      @title_hash.delete title_id unless existence
+      existence
     end
     remained_title_dirs = @title_ids.map { |id| title_hash[id].dir }
 
diff --git a/src/library/title.cr b/src/library/title.cr
index ed63471..def2b66 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -95,7 +95,9 @@ class Title
     previous_titles_size = @title_ids.size
     @title_ids.select! do |title_id|
       title = Library.default.get_title! title_id
-      title.examine cache
+      existence = title.examine cache
+      Library.default.title_hash.delete title_id unless existence
+      existence
     end
     remained_title_dirs = @title_ids.map do |title_id|
       title = Library.default.get_title! title_id

From 7734dae138c009f3e4c14ba9efc3a5984817e47e Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 14:36:17 +0900
Subject: [PATCH 16/39] Remove unnecessary sort

---
 src/util/signature.cr | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/signature.cr b/src/util/signature.cr
index e56aa06..b883e7c 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -70,7 +70,7 @@ class Dir
         end
       end
     end
-    hash = Digest::SHA1.hexdigest(signatures.sort.join)
+    hash = Digest::SHA1.hexdigest(signatures.join)
     cache[dirname] = hash
     hash
   end

From f5933a48d9ce4d7987b22524774a9efecdee8170 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 17:40:40 +0900
Subject: [PATCH 17/39] Register mime_type scan, thumbnails when loading
 instance

---
 src/library/library.cr | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index a7b43e9..f9edb7e 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -44,19 +44,11 @@ class Library
     zip_file.close
 
     if is_loaded
-      spawn do
-        start = Time.local
-        Library.default.scan
-        ms = (Time.local - start).total_milliseconds
-        Logger.info "Re-scanned #{Library.default.title_ids.size} titles \
-          in #{ms}ms"
-      end
+      Library.default.register_jobs
     end
   end
 
   def initialize
-    register_mime_types
-
     @dir = Config.current.library_path
     # explicitly initialize @titles to bypass the compiler check. it will
     #   be filled with actual Titles in the `scan` call below
@@ -66,6 +58,12 @@ class Library
     @entries_count = 0
     @thumbnails_count = 0
 
+    register_jobs
+  end
+
+  protected def register_jobs
+    register_mime_types
+
     scan_interval = Config.current.scan_interval_minutes
     if scan_interval < 1
       scan

From 8f1383a818a43788c37e67d6af041dc71df0581a Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 18:01:16 +0900
Subject: [PATCH 18/39] Use Gzip instead of Zip

---
 src/library/library.cr | 17 ++++-------------
 1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index f9edb7e..5b61827 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -10,8 +10,9 @@ class Library
     path = Config.current.library_path
     instance_file_path = File.join path, "library.yml.zip"
 
-    writer = Compress::Zip::Writer.new instance_file_path
-    writer.add "instance.yml", self.to_yaml
+    writer = Compress::Gzip::Writer.new instance_file_path,
+      Compress::Gzip::BEST_COMPRESSION
+    writer.write self.to_yaml.to_slice
     writer.close
   end
 
@@ -22,18 +23,10 @@ class Library
     return unless File.exists? instance_file_path
 
     Logger.debug "Load library instance"
-    zip_file = Compress::Zip::File.new instance_file_path
-    instance_file = zip_file.entries.find do |entry|
-      entry.filename == "instance.yml"
-    end
 
-    if instance_file.nil?
-      zip_file.close
-      return
-    end
     is_loaded = false
     begin
-      instance_file.open do |content|
+      Compress::Gzip::Reader.open instance_file_path do |content|
         @@default = Library.from_yaml content
       end
       is_loaded = true
@@ -41,8 +34,6 @@ class Library
       Logger.error e
     end
 
-    zip_file.close
-
     if is_loaded
       Library.default.register_jobs
     end

From a151ec486da746e078ac96e49015b43e9d701c4e Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sun, 12 Sep 2021 18:04:41 +0900
Subject: [PATCH 19/39] Fix file extension of gzip file

---
 src/library/library.cr | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 5b61827..7ab10df 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -8,7 +8,7 @@ class Library
 
   def save_instance
     path = Config.current.library_path
-    instance_file_path = File.join path, "library.yml.zip"
+    instance_file_path = File.join path, "library.yml.gz"
 
     writer = Compress::Gzip::Writer.new instance_file_path,
       Compress::Gzip::BEST_COMPRESSION
@@ -19,7 +19,7 @@ class Library
   def self.load_instance
     dir = Config.current.library_path
     return unless Dir.exists? dir
-    instance_file_path = File.join dir, "library.yml.zip"
+    instance_file_path = File.join dir, "library.yml.gz"
     return unless File.exists? instance_file_path
 
     Logger.debug "Load library instance"

From 03e044a1aa6b4d88a8d210b97c563f11204ada95 Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Tue, 14 Sep 2021 07:16:14 +0000
Subject: [PATCH 20/39] Improve logging

---
 src/library/library.cr | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 7ab10df..6d69563 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -9,6 +9,7 @@ class Library
   def save_instance
     path = Config.current.library_path
     instance_file_path = File.join path, "library.yml.gz"
+    Logger.debug "Caching library to #{instance_file_path}"
 
     writer = Compress::Gzip::Writer.new instance_file_path,
       Compress::Gzip::BEST_COMPRESSION
@@ -22,21 +23,16 @@ class Library
     instance_file_path = File.join dir, "library.yml.gz"
     return unless File.exists? instance_file_path
 
-    Logger.debug "Load library instance"
+    Logger.debug "Loading cached library from #{instance_file_path}"
 
-    is_loaded = false
     begin
       Compress::Gzip::Reader.open instance_file_path do |content|
         @@default = Library.from_yaml content
       end
-      is_loaded = true
+      Library.default.register_jobs
     rescue e
       Logger.error e
     end
-
-    if is_loaded
-      Library.default.register_jobs
-    end
   end
 
   def initialize
@@ -64,7 +60,7 @@ class Library
           start = Time.local
           scan
           ms = (Time.local - start).total_milliseconds
-          Logger.info "Scanned #{@title_ids.size} titles in #{ms}ms"
+          Logger.debug "Library initialized in #{ms}ms"
           sleep scan_interval.minutes
         end
       end
@@ -171,10 +167,13 @@ class Library
     storage.close
 
     ms = (Time.local - start).total_milliseconds
-    Logger.debug "Scan completed. #{ms}ms"
+    Logger.info "Scanned #{@title_ids.size} titles in #{ms}ms"
+
     Storage.default.mark_unavailable
 
-    save_instance
+    spawn do
+      save_instance
+    end
   end
 
   def get_continue_reading_entries(username)

From be47f309b09a61a32e2862dd9ce13b3ea7d4b217 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 18:11:08 +0900
Subject: [PATCH 21/39] Use cache when calculating contents_signature

---
 src/util/signature.cr | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/signature.cr b/src/util/signature.cr
index b883e7c..190a4a6 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -62,7 +62,7 @@ class Dir
         next if fn.starts_with? "."
         path = File.join dirname, fn
         if File.directory? path
-          signatures << Dir.contents_signature path
+          signatures << Dir.contents_signature path, cache
         else
           # Only add its signature value to `signatures` when it is a
           #   supported file

From 523195d6496bfd596afcc36f95654dd88edd05ee Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 22:37:30 +0900
Subject: [PATCH 22/39] Define ExamineContext, apply it when scanning

---
 src/library/library.cr | 12 ++++++++++--
 src/library/title.cr   | 17 +++++++++++------
 src/library/types.cr   |  7 +++++++
 src/util/signature.cr  |  4 ++--
 4 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 6d69563..582440a 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -142,20 +142,28 @@ class Library
 
     storage = Storage.new auto_close: false
 
+    examine_context : ExamineContext = {
+      file_count: 0,
+      cached_contents_signature: {} of String => String,
+      deleted_title_ids: [] of String,
+      deleted_entry_ids: [] of String
+    }
+
     @title_ids.select! do |title_id|
       title = @title_hash[title_id]
-      existence = title.examine
+      existence = title.examine examine_context
       @title_hash.delete title_id unless existence
       existence
     end
     remained_title_dirs = @title_ids.map { |id| title_hash[id].dir }
 
+    cache = examine_context["cached_contents_signature"]
     (Dir.entries @dir)
       .select { |fn| !fn.starts_with? "." }
       .map { |fn| File.join @dir, fn }
       .select { |path| !(remained_title_dirs.includes? path) }
       .select { |path| File.directory? path }
-      .map { |path| Title.new path, "" }
+      .map { |path| Title.new path, "", cache }
       .select { |title| !(title.entries.empty? && title.titles.empty?) }
       .sort! { |a, b| a.title <=> b.title }
       .each do |title|
diff --git a/src/library/title.cr b/src/library/title.cr
index def2b66..12c565f 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -19,7 +19,7 @@ class Title
   @[YAML::Field(ignore: true)]
   @cached_cover_url : String?
 
-  def initialize(@dir : String, @parent_id)
+  def initialize(@dir : String, @parent_id, cache : Hash(String, String)?)
     storage = Storage.default
     @signature = Dir.signature dir
     id = storage.get_title_id dir, signature
@@ -32,7 +32,7 @@ class Title
       })
     end
     @id = id
-    @contents_signature = Dir.contents_signature dir
+    @contents_signature = Dir.contents_signature dir, cache
     @title = File.basename dir
     @encoded_title = URI.encode @title
     @title_ids = [] of String
@@ -70,9 +70,14 @@ class Title
     end
   end
 
-  def examine(cache = {} of String => String) : Bool
+  def self.new(dir : String, parent_id)
+    new dir, parent_id, nil
+  end
+
+  def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
-    contents_signature = Dir.contents_signature @dir, cache
+    contents_signature = Dir.contents_signature @dir,
+      context["cached_contents_signature"]
     # Not changed. Reuse this
     return true if @contents_signature == contents_signature
 
@@ -95,7 +100,7 @@ class Title
     previous_titles_size = @title_ids.size
     @title_ids.select! do |title_id|
       title = Library.default.get_title! title_id
-      existence = title.examine cache
+      existence = title.examine context
       Library.default.title_hash.delete title_id unless existence
       existence
     end
@@ -115,7 +120,7 @@ class Title
       path = File.join dir, fn
       if File.directory? path
         next if remained_title_dirs.includes? path
-        title = Title.new path, @id
+        title = Title.new path, @id, context["cached_contents_signature"]
         next if title.entries.size == 0 && title.titles.size == 0
         Library.default.title_hash[title.id] = title
         @title_ids << title.id
diff --git a/src/library/types.cr b/src/library/types.cr
index 0545184..eb87545 100644
--- a/src/library/types.cr
+++ b/src/library/types.cr
@@ -133,3 +133,10 @@ class TitleInfo
     LRUCache.set generate_cache_entry key, self.to_json
   end
 end
+
+alias ExamineContext = NamedTuple(
+  file_count: Int32,
+  cached_contents_signature: Hash(String, String),
+  deleted_title_ids: Array(String),
+  deleted_entry_ids: Array(String)
+)
diff --git a/src/util/signature.cr b/src/util/signature.cr
index 190a4a6..c4104fe 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -55,7 +55,7 @@ class Dir
   #   - When a file added, moved, removed, renamed (including which in nested
   #       directories)
   def self.contents_signature(dirname, cache = {} of String => String) : String
-    return cache[dirname] if cache[dirname]?
+    return cache[dirname] if !cache.nil? && cache[dirname]?
     signatures = [] of String
     self.open dirname do |dir|
       dir.entries.sort.each do |fn|
@@ -71,7 +71,7 @@ class Dir
       end
     end
     hash = Digest::SHA1.hexdigest(signatures.join)
-    cache[dirname] = hash
+    cache[dirname] = hash unless cache.nil?
     hash
   end
 end

From 2e09efbd6238a331253a237736915d4f01788712 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 22:51:05 +0900
Subject: [PATCH 23/39] Collect deleted ids

---
 src/library/library.cr |  5 ++++-
 src/library/title.cr   | 11 +++++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 582440a..012d14b 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -152,7 +152,10 @@ class Library
     @title_ids.select! do |title_id|
       title = @title_hash[title_id]
       existence = title.examine examine_context
-      @title_hash.delete title_id unless existence
+      unless existence
+        @title_hash.delete title_id
+        examine_context["deleted_title_ids"] << title_id
+      end
       existence
     end
     remained_title_dirs = @title_ids.map { |id| title_hash[id].dir }
diff --git a/src/library/title.cr b/src/library/title.cr
index 12c565f..fb2d2fe 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -101,7 +101,10 @@ class Title
     @title_ids.select! do |title_id|
       title = Library.default.get_title! title_id
       existence = title.examine context
-      Library.default.title_hash.delete title_id unless existence
+      unless existence
+        Library.default.title_hash.delete title_id
+        context["deleted_title_ids"] << title_id
+      end
       existence
     end
     remained_title_dirs = @title_ids.map do |title_id|
@@ -110,7 +113,11 @@ class Title
     end
 
     previous_entries_size = @entries.size
-    @entries.select! { |entry| File.exists? entry.zip_path }
+    @entries.select! do |entry|
+      existence = File.exists? entry.zip_path
+      context["deleted_entry_ids"] << entry.id unless existence
+      existence
+    end
     remained_entry_zip_paths = @entries.map &.zip_path
 
     is_titles_added = false

From 670cf54957c744acfc94b3fe6985248792cd1806 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 22:51:37 +0900
Subject: [PATCH 24/39] Apply yield forcely

---
 src/library/title.cr  | 1 +
 src/library/types.cr  | 5 +++++
 src/util/signature.cr | 1 +
 3 files changed, 7 insertions(+)

diff --git a/src/library/title.cr b/src/library/title.cr
index fb2d2fe..1a8d488 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -115,6 +115,7 @@ class Title
     previous_entries_size = @entries.size
     @entries.select! do |entry|
       existence = File.exists? entry.zip_path
+      yield_process_file context
       context["deleted_entry_ids"] << entry.id unless existence
       existence
     end
diff --git a/src/library/types.cr b/src/library/types.cr
index eb87545..1355fcd 100644
--- a/src/library/types.cr
+++ b/src/library/types.cr
@@ -140,3 +140,8 @@ alias ExamineContext = NamedTuple(
   deleted_title_ids: Array(String),
   deleted_entry_ids: Array(String)
 )
+
+def yield_process_file(context : ExamineContext)
+  context["file_count"] += 1
+  Fiber.yield if context["file_count"] % 1000 == 0
+end
diff --git a/src/util/signature.cr b/src/util/signature.cr
index c4104fe..d0a55a6 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -56,6 +56,7 @@ class Dir
   #       directories)
   def self.contents_signature(dirname, cache = {} of String => String) : String
     return cache[dirname] if !cache.nil? && cache[dirname]?
+    Fiber.yield # Yield first
     signatures = [] of String
     self.open dirname do |dir|
       dir.entries.sort.each do |fn|

From 9489d6abfdac6af1fab3a805b48639081dbe987a Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 23:07:47 +0900
Subject: [PATCH 25/39] Use reference instead of primitive

---
 src/library/library.cr |  6 +++---
 src/library/title.cr   |  2 +-
 src/library/types.cr   | 23 +++++++++++++++--------
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 012d14b..0a04b1a 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -143,10 +143,10 @@ class Library
     storage = Storage.new auto_close: false
 
     examine_context : ExamineContext = {
-      file_count: 0,
+      file_counter:              (YieldCounter.new 1000),
       cached_contents_signature: {} of String => String,
-      deleted_title_ids: [] of String,
-      deleted_entry_ids: [] of String
+      deleted_title_ids:         [] of String,
+      deleted_entry_ids:         [] of String,
     }
 
     @title_ids.select! do |title_id|
diff --git a/src/library/title.cr b/src/library/title.cr
index 1a8d488..fcc5f2f 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -115,7 +115,7 @@ class Title
     previous_entries_size = @entries.size
     @entries.select! do |entry|
       existence = File.exists? entry.zip_path
-      yield_process_file context
+      context["file_counter"].count_and_yield
       context["deleted_entry_ids"] << entry.id unless existence
       existence
     end
diff --git a/src/library/types.cr b/src/library/types.cr
index 1355fcd..7856660 100644
--- a/src/library/types.cr
+++ b/src/library/types.cr
@@ -134,14 +134,21 @@ class TitleInfo
   end
 end
 
+class YieldCounter
+  setter threshold : Int32
+
+  def initialize(@threshold : Int32)
+    @file_count = 0
+  end
+
+  def count_and_yield
+    @file_count += 1
+    Fiber.yield if @file_count % @threshold == 0
+  end
+end
+
 alias ExamineContext = NamedTuple(
-  file_count: Int32,
+  file_counter: YieldCounter,
   cached_contents_signature: Hash(String, String),
   deleted_title_ids: Array(String),
-  deleted_entry_ids: Array(String)
-)
-
-def yield_process_file(context : ExamineContext)
-  context["file_count"] += 1
-  Fiber.yield if context["file_count"] % 1000 == 0
-end
+  deleted_entry_ids: Array(String))

From 57b2f7c625ad83fbbc2d08012a84c46ffc27c3c8 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 23:08:07 +0900
Subject: [PATCH 26/39] Get nested ids when title removed

---
 src/library/library.cr | 3 ++-
 src/library/title.cr   | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 0a04b1a..6cf8c32 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -153,8 +153,9 @@ class Library
       title = @title_hash[title_id]
       existence = title.examine examine_context
       unless existence
+        examine_context["deleted_title_ids"].concat title.deep_titles.map &.id
+        examine_context["deleted_entry_ids"].concat title.deep_entries.map &.id
         @title_hash.delete title_id
-        examine_context["deleted_title_ids"] << title_id
       end
       existence
     end
diff --git a/src/library/title.cr b/src/library/title.cr
index fcc5f2f..db2ca30 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -102,8 +102,9 @@ class Title
       title = Library.default.get_title! title_id
       existence = title.examine context
       unless existence
+        context["deleted_title_ids"].concat title.deep_titles.map &.id
+        context["deleted_entry_ids"].concat title.deep_entries.map &.id
         Library.default.title_hash.delete title_id
-        context["deleted_title_ids"] << title_id
       end
       existence
     end

From 663c0c0b38e47944e0da0d228b3593cdf317c871 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 23:15:40 +0900
Subject: [PATCH 27/39] Remove nested title including self

---
 src/library/library.cr | 6 ++++--
 src/library/title.cr   | 3 +--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 6cf8c32..8029fcb 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -153,13 +153,15 @@ class Library
       title = @title_hash[title_id]
       existence = title.examine examine_context
       unless existence
-        examine_context["deleted_title_ids"].concat title.deep_titles.map &.id
+        examine_context["deleted_title_ids"].concat [title_id] + title.deep_titles.map &.id
         examine_context["deleted_entry_ids"].concat title.deep_entries.map &.id
-        @title_hash.delete title_id
       end
       existence
     end
     remained_title_dirs = @title_ids.map { |id| title_hash[id].dir }
+    examine_context["deleted_title_ids"].each do |title_id|
+      @title_hash.delete title_id
+    end
 
     cache = examine_context["cached_contents_signature"]
     (Dir.entries @dir)
diff --git a/src/library/title.cr b/src/library/title.cr
index db2ca30..6bae693 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -102,9 +102,8 @@ class Title
       title = Library.default.get_title! title_id
       existence = title.examine context
       unless existence
-        context["deleted_title_ids"].concat title.deep_titles.map &.id
+        context["deleted_title_ids"].concat [title_id] + title.deep_titles.map &.id
         context["deleted_entry_ids"].concat title.deep_entries.map &.id
-        Library.default.title_hash.delete title_id
       end
       existence
     end

From f4d7128b59fd229031735fac38006ba4a86ce7f8 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Tue, 14 Sep 2021 23:30:03 +0900
Subject: [PATCH 28/39] Mark unavailable only in candidates

---
 src/library/library.cr |  3 ++-
 src/storage.cr         | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 8029fcb..12d662f 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -183,7 +183,8 @@ class Library
     ms = (Time.local - start).total_milliseconds
     Logger.info "Scanned #{@title_ids.size} titles in #{ms}ms"
 
-    Storage.default.mark_unavailable
+    Storage.default.mark_unavailable examine_context["deleted_entry_ids"],
+      examine_context["deleted_title_ids"]
 
     spawn do
       save_instance
diff --git a/src/storage.cr b/src/storage.cr
index 39116b9..1f0aab7 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -466,6 +466,47 @@ class Storage
     end
   end
 
+  # Limit mark targets with given arguments
+  def mark_unavailable(trash_ids_candidates : Array(String), trash_titles_candidates : Array(String))
+    MainFiber.run do
+      get_db do |db|
+        # Detect dangling entry IDs
+        trash_ids = [] of String
+        db.query "select path, id from ids where id in " \
+                 "(#{trash_ids_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+          rs.each do
+            path = rs.read String
+            fullpath = Path.new(path).expand(Config.current.library_path).to_s
+            trash_ids << rs.read String unless File.exists? fullpath
+          end
+        end
+
+        unless trash_ids.empty?
+          Logger.debug "Marking #{trash_ids.size} entries as unavailable"
+        end
+        db.exec "update ids set unavailable = 1 where id in " \
+                "(#{trash_ids.join "," { |i| "'#{i}'" }})"
+
+        # Detect dangling title IDs
+        trash_titles = [] of String
+        db.query "select path, id from titles where id in " \
+                 "(#{trash_titles_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+          rs.each do
+            path = rs.read String
+            fullpath = Path.new(path).expand(Config.current.library_path).to_s
+            trash_titles << rs.read String unless Dir.exists? fullpath
+          end
+        end
+
+        unless trash_titles.empty?
+          Logger.debug "Marking #{trash_titles.size} titles as unavailable"
+        end
+        db.exec "update titles set unavailable = 1 where id in " \
+                "(#{trash_titles.join "," { |i| "'#{i}'" }})"
+      end
+    end
+  end
+
   private def get_missing(tablename)
     ary = [] of IDTuple
     MainFiber.run do

From a3b2cdd372d546612e8806143b9baddce7cad415 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Wed, 15 Sep 2021 01:17:44 +0900
Subject: [PATCH 29/39] Lint

---
 src/library/library.cr | 3 ++-
 src/library/title.cr   | 3 ++-
 src/storage.cr         | 7 ++++---
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/library/library.cr b/src/library/library.cr
index 12d662f..b50fb87 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -153,7 +153,8 @@ class Library
       title = @title_hash[title_id]
       existence = title.examine examine_context
       unless existence
-        examine_context["deleted_title_ids"].concat [title_id] + title.deep_titles.map &.id
+        examine_context["deleted_title_ids"].concat [title_id] +
+                                                    title.deep_titles.map &.id
         examine_context["deleted_entry_ids"].concat title.deep_entries.map &.id
       end
       existence
diff --git a/src/library/title.cr b/src/library/title.cr
index 6bae693..41efd7c 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -102,7 +102,8 @@ class Title
       title = Library.default.get_title! title_id
       existence = title.examine context
       unless existence
-        context["deleted_title_ids"].concat [title_id] + title.deep_titles.map &.id
+        context["deleted_title_ids"].concat [title_id] +
+                                            title.deep_titles.map &.id
         context["deleted_entry_ids"].concat title.deep_entries.map &.id
       end
       existence
diff --git a/src/storage.cr b/src/storage.cr
index 1f0aab7..2f01863 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -467,13 +467,14 @@ class Storage
   end
 
   # Limit mark targets with given arguments
-  def mark_unavailable(trash_ids_candidates : Array(String), trash_titles_candidates : Array(String))
+  def mark_unavailable(ids_candidates : Array(String),
+                       titles_candidates : Array(String))
     MainFiber.run do
       get_db do |db|
         # Detect dangling entry IDs
         trash_ids = [] of String
         db.query "select path, id from ids where id in " \
-                 "(#{trash_ids_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+                 "(#{ids_candidates.join "," { |i| "'#{i}'" }})" do |rs|
           rs.each do
             path = rs.read String
             fullpath = Path.new(path).expand(Config.current.library_path).to_s
@@ -490,7 +491,7 @@ class Storage
         # Detect dangling title IDs
         trash_titles = [] of String
         db.query "select path, id from titles where id in " \
-                 "(#{trash_titles_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+                 "(#{titles_candidates.join "," { |i| "'#{i}'" }})" do |rs|
           rs.each do
             path = rs.read String
             fullpath = Path.new(path).expand(Config.current.library_path).to_s

From d13cfc045fd344e4557f882bdc1eb748fb8bc0a0 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Wed, 15 Sep 2021 01:27:05 +0900
Subject: [PATCH 30/39] Add a comment

---
 src/storage.cr | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/storage.cr b/src/storage.cr
index 2f01863..4511255 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -467,6 +467,8 @@ class Storage
   end
 
   # Limit mark targets with given arguments
+  # They should be checked again if they are really gone,
+  #   since they would be available which are renamed or moved
   def mark_unavailable(ids_candidates : Array(String),
                        titles_candidates : Array(String))
     MainFiber.run do

From de193906a2b3bf72ea255e330621fceea9edcac0 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Wed, 15 Sep 2021 16:54:55 +0900
Subject: [PATCH 31/39] Refactor mark_unavailable

---
 src/storage.cr | 55 +++++++++++++-------------------------------------
 1 file changed, 14 insertions(+), 41 deletions(-)

diff --git a/src/storage.cr b/src/storage.cr
index 4511255..9f6f45b 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -429,54 +429,24 @@ class Storage
   end
 
   def mark_unavailable
-    MainFiber.run do
-      get_db do |db|
-        # Detect dangling entry IDs
-        trash_ids = [] of String
-        db.query "select path, id from ids where unavailable = 0" do |rs|
-          rs.each do
-            path = rs.read String
-            fullpath = Path.new(path).expand(Config.current.library_path).to_s
-            trash_ids << rs.read String unless File.exists? fullpath
-          end
-        end
-
-        unless trash_ids.empty?
-          Logger.debug "Marking #{trash_ids.size} entries as unavailable"
-        end
-        db.exec "update ids set unavailable = 1 where id in " \
-                "(#{trash_ids.join "," { |i| "'#{i}'" }})"
-
-        # Detect dangling title IDs
-        trash_titles = [] of String
-        db.query "select path, id from titles where unavailable  = 0" do |rs|
-          rs.each do
-            path = rs.read String
-            fullpath = Path.new(path).expand(Config.current.library_path).to_s
-            trash_titles << rs.read String unless Dir.exists? fullpath
-          end
-        end
-
-        unless trash_titles.empty?
-          Logger.debug "Marking #{trash_titles.size} titles as unavailable"
-        end
-        db.exec "update titles set unavailable = 1 where id in " \
-                "(#{trash_titles.join "," { |i| "'#{i}'" }})"
-      end
-    end
+    mark_unavailable nil, nil
   end
 
   # Limit mark targets with given arguments
   # They should be checked again if they are really gone,
   #   since they would be available which are renamed or moved
-  def mark_unavailable(ids_candidates : Array(String),
-                       titles_candidates : Array(String))
+  def mark_unavailable(ids_candidates : Array(String) | Nil,
+                       titles_candidates : Array(String) | Nil)
     MainFiber.run do
       get_db do |db|
         # Detect dangling entry IDs
         trash_ids = [] of String
-        db.query "select path, id from ids where id in " \
-                 "(#{ids_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+        # Use query builder instead?
+        query = "select path, id from ids where unavailable = 0"
+        unless ids_candidates.nil?
+          query += " and id in (#{ids_candidates.join "," { |i| "'#{i}'" }})"
+        end
+        db.query query do |rs|
           rs.each do
             path = rs.read String
             fullpath = Path.new(path).expand(Config.current.library_path).to_s
@@ -492,8 +462,11 @@ class Storage
 
         # Detect dangling title IDs
         trash_titles = [] of String
-        db.query "select path, id from titles where id in " \
-                 "(#{titles_candidates.join "," { |i| "'#{i}'" }})" do |rs|
+        query = "select path, id from titles where unavailable = 0"
+        unless titles_candidates.nil?
+          query += " and id in (#{titles_candidates.join "," { |i| "'#{i}'" }})"
+        end
+        db.query query do |rs|
           rs.each do
             path = rs.read String
             fullpath = Path.new(path).expand(Config.current.library_path).to_s

From d330db131e52ad0c62ffbf6e0df0568662813551 Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Wed, 15 Sep 2021 08:46:30 +0000
Subject: [PATCH 32/39] Simplify `mark_unavailable`

---
 src/storage.cr | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/storage.cr b/src/storage.cr
index 9f6f45b..762946d 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -428,15 +428,11 @@ class Storage
     end
   end
 
-  def mark_unavailable
-    mark_unavailable nil, nil
-  end
-
   # Limit mark targets with given arguments
   # They should be checked again if they are really gone,
   #   since they would be available which are renamed or moved
-  def mark_unavailable(ids_candidates : Array(String) | Nil,
-                       titles_candidates : Array(String) | Nil)
+  def mark_unavailable(ids_candidates : Array(String)?,
+                       titles_candidates : Array(String)?)
     MainFiber.run do
       get_db do |db|
         # Detect dangling entry IDs

From 44a6f822cd2d69156beb359dfa26b522f47e875d Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Wed, 15 Sep 2021 09:00:30 +0000
Subject: [PATCH 33/39] Simplify Title.new

---
 src/library/title.cr | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 3abc38d..ee1edd0 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -19,7 +19,7 @@ class Title
   @[YAML::Field(ignore: true)]
   @cached_cover_url : String?
 
-  def initialize(@dir : String, @parent_id, cache : Hash(String, String)?)
+  def initialize(@dir : String, @parent_id, cache : Hash(String, String)? = nil)
     storage = Storage.default
     @signature = Dir.signature dir
     id = storage.get_title_id dir, signature
@@ -70,10 +70,6 @@ class Title
     end
   end
 
-  def self.new(dir : String, parent_id)
-    new dir, parent_id, nil
-  end
-
   def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
     contents_signature = Dir.contents_signature @dir,

From 70ab198a33ee34bba7c1ce8f1152918a81316569 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Thu, 16 Sep 2021 00:16:26 +0900
Subject: [PATCH 34/39] Add config 'forcely_yield_count'

the default value 1000 would make a fiber yield on each 4ms on SSD

Apply yield counter in Dir.contents_signauture
Use contents_signature cache in Title.new
---
 src/config.cr          |  1 +
 src/library/library.cr |  3 ++-
 src/library/title.cr   |  6 +++---
 src/util/signature.cr  | 11 +++++++----
 4 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/src/config.cr b/src/config.cr
index 99fb5b9..bc7aa18 100644
--- a/src/config.cr
+++ b/src/config.cr
@@ -23,6 +23,7 @@ class Config
   property cache_enabled = false
   property cache_size_mbs = 50
   property cache_log_enabled = true
+  property forcely_yield_count = 1000
   property disable_login = false
   property default_username = ""
   property auth_proxy_header_name = ""
diff --git a/src/library/library.cr b/src/library/library.cr
index ea2a5e3..de8d7b4 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -133,8 +133,9 @@ class Library
 
     storage = Storage.new auto_close: false
 
+    count = Config.current.forcely_yield_count
     examine_context : ExamineContext = {
-      file_counter:              (YieldCounter.new 1000),
+      file_counter:              (YieldCounter.new count),
       cached_contents_signature: {} of String => String,
       deleted_title_ids:         [] of String,
       deleted_entry_ids:         [] of String,
diff --git a/src/library/title.cr b/src/library/title.cr
index ee1edd0..f57024c 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -19,7 +19,7 @@ class Title
   @[YAML::Field(ignore: true)]
   @cached_cover_url : String?
 
-  def initialize(@dir : String, @parent_id, cache : Hash(String, String)? = nil)
+  def initialize(@dir : String, @parent_id, cache = {} of String => String)
     storage = Storage.default
     @signature = Dir.signature dir
     id = storage.get_title_id dir, signature
@@ -43,7 +43,7 @@ class Title
       next if fn.starts_with? "."
       path = File.join dir, fn
       if File.directory? path
-        title = Title.new path, @id
+        title = Title.new path, @id, cache
         next if title.entries.size == 0 && title.titles.size == 0
         Library.default.title_hash[title.id] = title
         @title_ids << title.id
@@ -73,7 +73,7 @@ class Title
   def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
     contents_signature = Dir.contents_signature @dir,
-      context["cached_contents_signature"]
+      context["cached_contents_signature"], context["file_counter"]
     # Not changed. Reuse this
     return true if @contents_signature == contents_signature
 
diff --git a/src/util/signature.cr b/src/util/signature.cr
index d0a55a6..59a8311 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -54,9 +54,11 @@ class Dir
   # Rescan conditions:
   #   - When a file added, moved, removed, renamed (including which in nested
   #       directories)
-  def self.contents_signature(dirname, cache = {} of String => String) : String
-    return cache[dirname] if !cache.nil? && cache[dirname]?
-    Fiber.yield # Yield first
+  def self.contents_signature(dirname,
+                              cache = {} of String => String,
+                              counter : YieldCounter? = nil) : String
+    return cache[dirname] if cache[dirname]?
+    counter.count_and_yield unless counter.nil?
     signatures = [] of String
     self.open dirname do |dir|
       dir.entries.sort.each do |fn|
@@ -69,10 +71,11 @@ class Dir
           #   supported file
           signatures << fn if is_supported_file fn
         end
+        counter.count_and_yield unless counter.nil?
       end
     end
     hash = Digest::SHA1.hexdigest(signatures.join)
-    cache[dirname] = hash unless cache.nil?
+    cache[dirname] = hash
     hash
   end
 end

From 9769e760a0ad0ce9035ad350185497942b280795 Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Thu, 16 Sep 2021 07:49:12 +0900
Subject: [PATCH 35/39] Pass a counter to recursive calls, Ignore negative
 threshold

---
 src/library/types.cr  | 4 ++--
 src/util/signature.cr | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/library/types.cr b/src/library/types.cr
index 7856660..a0e0428 100644
--- a/src/library/types.cr
+++ b/src/library/types.cr
@@ -135,7 +135,7 @@ class TitleInfo
 end
 
 class YieldCounter
-  setter threshold : Int32
+  @file_count : UInt32
 
   def initialize(@threshold : Int32)
     @file_count = 0
@@ -143,7 +143,7 @@ class YieldCounter
 
   def count_and_yield
     @file_count += 1
-    Fiber.yield if @file_count % @threshold == 0
+    Fiber.yield if @threshold > 0 && @file_count % @threshold == 0
   end
 end
 
diff --git a/src/util/signature.cr b/src/util/signature.cr
index 59a8311..76e2628 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -65,7 +65,7 @@ class Dir
         next if fn.starts_with? "."
         path = File.join dirname, fn
         if File.directory? path
-          signatures << Dir.contents_signature path, cache
+          signatures << Dir.contents_signature path, cache, counter
         else
           # Only add its signature value to `signatures` when it is a
           #   supported file

From b56e16e1e19bca9a654fc813d79674159c1c42ea Mon Sep 17 00:00:00 2001
From: Leeingnyo <dyd1928@naver.com>
Date: Sat, 18 Sep 2021 10:59:43 +0900
Subject: [PATCH 36/39] Remove counter, yield everytime

---
 src/config.cr          |  1 -
 src/library/library.cr |  2 --
 src/library/title.cr   |  4 ++--
 src/library/types.cr   | 14 --------------
 src/util/signature.cr  | 10 ++++------
 5 files changed, 6 insertions(+), 25 deletions(-)

diff --git a/src/config.cr b/src/config.cr
index bc7aa18..99fb5b9 100644
--- a/src/config.cr
+++ b/src/config.cr
@@ -23,7 +23,6 @@ class Config
   property cache_enabled = false
   property cache_size_mbs = 50
   property cache_log_enabled = true
-  property forcely_yield_count = 1000
   property disable_login = false
   property default_username = ""
   property auth_proxy_header_name = ""
diff --git a/src/library/library.cr b/src/library/library.cr
index de8d7b4..ce1a8fc 100644
--- a/src/library/library.cr
+++ b/src/library/library.cr
@@ -133,9 +133,7 @@ class Library
 
     storage = Storage.new auto_close: false
 
-    count = Config.current.forcely_yield_count
     examine_context : ExamineContext = {
-      file_counter:              (YieldCounter.new count),
       cached_contents_signature: {} of String => String,
       deleted_title_ids:         [] of String,
       deleted_entry_ids:         [] of String,
diff --git a/src/library/title.cr b/src/library/title.cr
index f57024c..6a959d8 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -73,7 +73,7 @@ class Title
   def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
     contents_signature = Dir.contents_signature @dir,
-      context["cached_contents_signature"], context["file_counter"]
+      context["cached_contents_signature"]
     # Not changed. Reuse this
     return true if @contents_signature == contents_signature
 
@@ -112,7 +112,7 @@ class Title
     previous_entries_size = @entries.size
     @entries.select! do |entry|
       existence = File.exists? entry.zip_path
-      context["file_counter"].count_and_yield
+      Fiber.yield
       context["deleted_entry_ids"] << entry.id unless existence
       existence
     end
diff --git a/src/library/types.cr b/src/library/types.cr
index a0e0428..4c9dc93 100644
--- a/src/library/types.cr
+++ b/src/library/types.cr
@@ -134,21 +134,7 @@ class TitleInfo
   end
 end
 
-class YieldCounter
-  @file_count : UInt32
-
-  def initialize(@threshold : Int32)
-    @file_count = 0
-  end
-
-  def count_and_yield
-    @file_count += 1
-    Fiber.yield if @threshold > 0 && @file_count % @threshold == 0
-  end
-end
-
 alias ExamineContext = NamedTuple(
-  file_counter: YieldCounter,
   cached_contents_signature: Hash(String, String),
   deleted_title_ids: Array(String),
   deleted_entry_ids: Array(String))
diff --git a/src/util/signature.cr b/src/util/signature.cr
index 76e2628..5ca3e14 100644
--- a/src/util/signature.cr
+++ b/src/util/signature.cr
@@ -54,24 +54,22 @@ class Dir
   # Rescan conditions:
   #   - When a file added, moved, removed, renamed (including which in nested
   #       directories)
-  def self.contents_signature(dirname,
-                              cache = {} of String => String,
-                              counter : YieldCounter? = nil) : String
+  def self.contents_signature(dirname, cache = {} of String => String) : String
     return cache[dirname] if cache[dirname]?
-    counter.count_and_yield unless counter.nil?
+    Fiber.yield
     signatures = [] of String
     self.open dirname do |dir|
       dir.entries.sort.each do |fn|
         next if fn.starts_with? "."
         path = File.join dirname, fn
         if File.directory? path
-          signatures << Dir.contents_signature path, cache, counter
+          signatures << Dir.contents_signature path, cache
         else
           # Only add its signature value to `signatures` when it is a
           #   supported file
           signatures << fn if is_supported_file fn
         end
-        counter.count_and_yield unless counter.nil?
+        Fiber.yield
       end
     end
     hash = Digest::SHA1.hexdigest(signatures.join)

From 96f1ef3dde56cc4132f69a0f22be810443281440 Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Sat, 18 Sep 2021 02:00:10 +0000
Subject: [PATCH 37/39] Improve comments on examine

---
 src/library/title.cr | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index f57024c..f9499c1 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -70,14 +70,21 @@ class Title
     end
   end
 
+  # Utility method used in library rescanning.
+  # - When the title does not exist on the file system anymore, return false
+  #     and let it be deleted from the libaray instance
+  # - When the title exists, but its contents sigature is now different from
+  #     the cache, it means some of its content (nested titles or entries)
+  #     has been added, deleted, or renamed. In this case we update its
+  #     contents signature and instance variables
+  # - When the title exists and its contents sigature is still the same, we
+  #     return true so it can be reused without rescanning
   def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
     contents_signature = Dir.contents_signature @dir,
       context["cached_contents_signature"], context["file_counter"]
-    # Not changed. Reuse this
     return true if @contents_signature == contents_signature
 
-    # Fix title
     @contents_signature = contents_signature
     @signature = Dir.signature @dir
     storage = Storage.default
@@ -160,7 +167,7 @@ class Title
       end
     end
 
-    true # Fixed, reuse this
+    true
   end
 
   alias SortContext = NamedTuple(username: String, opt: SortOptions)

From 3f73591dd44fbd705de2cc9bd4b936fa3d16ddf8 Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Sat, 18 Sep 2021 02:14:22 +0000
Subject: [PATCH 38/39] Update comments

---
 src/library/title.cr | 6 +++---
 src/storage.cr       | 7 ++++---
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 853ed1c..1709e9b 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -72,12 +72,12 @@ class Title
 
   # Utility method used in library rescanning.
   # - When the title does not exist on the file system anymore, return false
-  #     and let it be deleted from the libaray instance
-  # - When the title exists, but its contents sigature is now different from
+  #     and let it be deleted from the library instance
+  # - When the title exists, but its contents signature is now different from
   #     the cache, it means some of its content (nested titles or entries)
   #     has been added, deleted, or renamed. In this case we update its
   #     contents signature and instance variables
-  # - When the title exists and its contents sigature is still the same, we
+  # - When the title exists and its contents signature is still the same, we
   #     return true so it can be reused without rescanning
   def examine(context : ExamineContext) : Bool
     return false unless Dir.exists? @dir # No title, Remove this
diff --git a/src/storage.cr b/src/storage.cr
index 762946d..eea5927 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -428,9 +428,10 @@ class Storage
     end
   end
 
-  # Limit mark targets with given arguments
-  # They should be checked again if they are really gone,
-  #   since they would be available which are renamed or moved
+  # Mark titles and entries that no longer exist on the file system as
+  #   unavailable. By supplying `id_candidates` and `titles_candidates`, it
+  #   only checks the existence of the candidate titles/entries to speed up
+  #   the process.
   def mark_unavailable(ids_candidates : Array(String)?,
                        titles_candidates : Array(String)?)
     MainFiber.run do

From 16397050dd7604b0ab2f21aec3a573041052cd90 Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Sat, 18 Sep 2021 02:24:50 +0000
Subject: [PATCH 39/39] Update comments

---
 src/library/title.cr | 2 +-
 src/storage.cr       | 1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/library/title.cr b/src/library/title.cr
index 1709e9b..7efee42 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -80,7 +80,7 @@ class Title
   # - When the title exists and its contents signature is still the same, we
   #     return true so it can be reused without rescanning
   def examine(context : ExamineContext) : Bool
-    return false unless Dir.exists? @dir # No title, Remove this
+    return false unless Dir.exists? @dir
     contents_signature = Dir.contents_signature @dir,
       context["cached_contents_signature"]
     return true if @contents_signature == contents_signature
diff --git a/src/storage.cr b/src/storage.cr
index eea5927..32f446a 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -438,7 +438,6 @@ class Storage
       get_db do |db|
         # Detect dangling entry IDs
         trash_ids = [] of String
-        # Use query builder instead?
         query = "select path, id from ids where unavailable = 0"
         unless ids_candidates.nil?
           query += " and id in (#{ids_candidates.join "," { |i| "'#{i}'" }})"