#351

backend/app/models/post.rb

@@ -86,7 +86,7 @@ class Post < ApplicationRecord
   end
 
   def self.section_literal section
-    "[#{ Post.ms_to_time(section.begin_ms) }-#{ Post.ms_to_time(section.end_ms) }]"
+    "[#{ Post.ms_to_time(section.begin_ms) }-#{ section.end_ms ? Post.ms_to_time(section.end_ms) : '' }]"
   end
 
   def self.ms_to_time ms

backend/app/models/post_tag_section.rb

@@ -15,6 +15,6 @@ class PostTagSection < ApplicationRecord
   validates :begin_ms, presence: true,
                        numericality: { only_integer: true, greater_than_or_equal_to: 0 }
 
-  validates :end_ms, presence: true,
-                     numericality: { only_integer: true, greater_than: :begin_ms }
+  validates :end_ms, numericality: { only_integer: true, greater_than: :begin_ms },
+                     allow_nil: true
 end

backend/app/models/tag.rb

@@ -17,6 +17,16 @@ class Tag < ApplicationRecord
     end
   end
 
+  class SectionLiteralParseError < ArgumentError
+    attr_reader :tag_name, :literal
+
+    def initialize tag_name, literal
+      @tag_name = tag_name
+      @literal = literal
+      super("invalid section literal for tag #{ tag_name }: #{ literal }")
+    end
+  end
+
   has_many :post_tags, inverse_of: :tag
   has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :tag
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
@@ -113,20 +123,22 @@ class Tag < ApplicationRecord
 
     sections = { }
     tags = tag_names.map do |name|
+      raw_name = name
       pf, cat = CATEGORY_PREFIXES.find { |p, _| name.downcase.start_with?(p) } || ['', nil]
 
       name = name.sub(/\A#{ pf }/i, '')
 
       sections_by_tag = []
-      while n = name.sub!(/^(\S*?)\[([0-9:.]*?)-([0-9:.]*?)\](\S*?)$/, '\1\4 \2 \3')
-        name, *section_raw = n.split
+      while (match = name.match(/\A(\S*?)\[([^\[\]\s]*)-([^\[\]\s]*)\](\S*)\z/))
+        name = "#{ match[1] }#{ match[4] }"
+        sections_by_tag << normalise_section_range!(
+            begin_raw: match[2],
+            end_raw: match[3],
+            tag_name: name)
+      end
 
-        begin_ms, end_ms = section_raw.map { time_to_ms(_1) }
-        next if begin_ms == end_ms
-
-        begin_ms, end_ms = end_ms, begin_ms if begin_ms > end_ms
-
-        sections_by_tag << [begin_ms, end_ms]
+      if name.include?('[') || name.include?(']')
+        raise SectionLiteralParseError.new(raw_name, raw_name)
       end
 
       name = TagName.canonicalise(name).first
@@ -141,6 +153,7 @@ class Tag < ApplicationRecord
 
         sections[tag.id] ||= []
         sections[tag.id].concat(sections_by_tag)
+        sections[tag.id] = merge_section_ranges(sections[tag.id])
       end
     end
 
@@ -178,6 +191,45 @@ class Tag < ApplicationRecord
     (result + tags).uniq { |t| t.id }
   end
 
+  def self.normalise_section_range! begin_raw:, end_raw:, tag_name:
+    begin_ms = begin_raw.empty? ? 0 : time_to_ms!(begin_raw, tag_name:)
+    end_ms = end_raw.empty? ? nil : time_to_ms!(end_raw, tag_name:)
+
+    if end_ms
+      begin_ms, end_ms = end_ms, begin_ms if begin_ms > end_ms
+      end_ms = begin_ms + 1 if begin_ms == end_ms
+    end
+
+    [begin_ms, end_ms]
+  end
+
+  def self.merge_section_ranges ranges
+    sorted_ranges = ranges.sort_by { |begin_ms, end_ms| [begin_ms, end_ms || Float::INFINITY] }
+    merged = []
+
+    sorted_ranges.each do |begin_ms, end_ms|
+      if merged.empty?
+        merged << [begin_ms, end_ms]
+        next
+      end
+
+      last_begin_ms, last_end_ms = merged[-1]
+      if last_end_ms.nil? || begin_ms <= last_end_ms
+        merged[-1] = [last_begin_ms, merge_section_end(last_end_ms, end_ms)]
+      else
+        merged << [begin_ms, end_ms]
+      end
+    end
+
+    merged
+  end
+
+  def self.merge_section_end left_end_ms, right_end_ms
+    return nil if left_end_ms.nil? || right_end_ms.nil?
+
+    [left_end_ms, right_end_ms].max
+  end
+
   def self.find_or_create_by_tag_name! name, category:
     tn = TagName.find_undiscard_or_create_by!(name: name.to_s.strip)
     tn = tn.canonical if tn.canonical_id?
@@ -274,23 +326,30 @@ class Tag < ApplicationRecord
     end
   end
 
-  def self.time_to_ms str
-    parts = str.split(':')
+  def self.time_to_ms! str, tag_name:
+    match =
+        case str
+        when /\A(?<seconds>\d+)(?:\.(?<ms>\d{1,3}))?\z/
+          { hours: nil, minutes: nil, seconds: Regexp.last_match[:seconds],
+            ms: Regexp.last_match[:ms] }
+        when /\A(?<minutes>\d+):(?<seconds>[0-5]?\d)(?:\.(?<ms>\d{1,3}))?\z/
+          { hours: nil, minutes: Regexp.last_match[:minutes],
+            seconds: Regexp.last_match[:seconds],
+            ms: Regexp.last_match[:ms] }
+        when /\A(?<hours>\d+):(?<minutes>[0-5]?\d):(?<seconds>[0-5]?\d)(?:\.(?<ms>\d{1,3}))?\z/
+          { hours: Regexp.last_match[:hours],
+            minutes: Regexp.last_match[:minutes],
+            seconds: Regexp.last_match[:seconds],
+            ms: Regexp.last_match[:ms] }
+        end
 
-    s_part = parts.pop
-    s, ms = s_part.split('.')
+    raise SectionLiteralParseError.new(tag_name, str) unless match
 
-    total_s = s.to_i
+    total_s = match[:seconds].to_i
+    total_s += match[:minutes].to_i * 60 if match[:minutes]
+    total_s += match[:hours].to_i * 3_600 if match[:hours]
 
-    if parts.length >= 1
-      total_s += parts.pop.to_i * 60
-    end
-
-    if parts.length >= 1
-      total_s += parts.pop.to_i * 3_600
-    end
-
-    total_s * 1_000 + ms.to_s.ljust(3, '0')[0, 3].to_i
+    total_s * 1_000 + match[:ms].to_s.ljust(3, '0')[0, 3].to_i
   end
 
   def nico_tags_cannot_be_deprecated