広場投稿追加画面の刷新 (#399) (#413)

Reviewed-on: #413
Co-authored-by: miteruzo <miteruzo@naver.com>
Co-committed-by: miteruzo <miteruzo@naver.com>

backend/app/services/post_creator.rb

@@ -0,0 +1,154 @@
+class PostCreator
+  class VideoMsParseError < ArgumentError; end
+
+  attr_reader :field_warnings
+
+  def initialize actor:, attributes:
+    @actor = actor
+    @attributes = attributes.symbolize_keys
+    @field_warnings = { }
+  end
+
+  def create!
+    thumbnail_attachment = prepare_thumbnail_attachment
+    post = Post.new(title: @attributes[:title].presence,
+                    url: @attributes[:url],
+                    thumbnail_base: @attributes[:thumbnail_base].presence,
+                    uploaded_user: @actor,
+                    original_created_from: @attributes[:original_created_from].presence,
+                    original_created_before: @attributes[:original_created_before].presence)
+
+    ApplicationRecord.transaction do
+      post.save!
+      post.thumbnail.attach(thumbnail_attachment) if thumbnail_attachment.present?
+      snapshot_tags = planned_snapshot_tags
+      post_tags = planned_post_tags
+      sections = planned_sections
+      TagVersioning.record_tag_snapshots!(snapshot_tags, created_by_user: @actor)
+      post.video_ms = planned_video_ms
+      post.save!
+      sync_post_tags!(post, post_tags, sections)
+      sync_parent_posts!(post, planned_parent_post_ids)
+      PostVersionRecorder.record!(post:, event_type: :create, created_by_user: @actor)
+    end
+    post
+  rescue StandardError
+    post&.thumbnail&.purge if post&.thumbnail&.attached?
+    raise
+  end
+
+  private
+
+  def prepare_thumbnail_attachment
+    PostThumbnailAttachmentBuilder.build(
+        thumbnail: @attributes[:thumbnail],
+        thumbnail_base: @attributes[:thumbnail_base].presence)
+  end
+
+  def planned_snapshot_tags = planned_create_attributes[:snapshot_tags]
+
+  def planned_post_tags = planned_create_attributes[:post_tags]
+
+  def planned_sections = planned_create_attributes[:tag_sections]
+
+  def planned_parent_post_ids = planned_create_attributes[:normalised_parent_post_ids]
+
+  def planned_video_ms
+    planned_create_attributes[:video_ms]
+  end
+
+  def planned_create_attributes
+    @planned_create_attributes ||= begin
+      if @attributes.key?(:snapshot_tag_specs)
+        snapshot_tags = materialise_tags(@attributes[:snapshot_tag_specs] || [])
+        post_tags = materialise_tags(@attributes[:post_tag_specs] || [])
+        {
+            snapshot_tags: snapshot_tags,
+            post_tags: post_tags,
+            tag_sections: materialise_sections(
+                @attributes[:tag_sections] || { },
+                snapshot_tags,
+                post_tags),
+            normalised_parent_post_ids: @attributes[:normalised_parent_post_ids] || [],
+            video_ms: @attributes[:video_ms] }
+      else
+        build_materialised_plan
+      end
+    end
+  end
+
+  def build_materialised_plan
+    plan = PostCreatePlan.new(attributes: @attributes).build!
+    snapshot_tags = materialise_tags(plan[:snapshot_tag_specs] || [])
+    post_tags = materialise_tags(plan[:post_tag_specs] || [])
+    {
+        snapshot_tags: snapshot_tags,
+        post_tags: post_tags,
+        tag_sections: materialise_sections(
+            plan[:tag_sections] || { },
+            snapshot_tags,
+            post_tags),
+        normalised_parent_post_ids: plan[:normalised_parent_post_ids] || [],
+        video_ms: plan[:video_ms] }
+  end
+
+  def materialise_tags specs
+    Array(specs).each_with_object({ }) do |spec, tags|
+      name = spec[:name] || spec['name']
+      category = spec[:category] || spec['category']
+      next if name.blank? || category.blank?
+
+      tag = Tag.find_or_create_by_tag_name!(name, category:)
+      tag.update!(category:) if tag.category.to_sym != category.to_sym
+      tags[name] ||= tag
+    end.values
+  end
+
+  def materialise_sections sections_by_name, snapshot_tags, post_tags
+    tags_by_name = post_tags.index_by(&:name)
+    snapshot_tags.each do |tag|
+      tags_by_name[tag.name] ||= tag
+    end
+
+    sections_by_name.each_with_object({ }) do |(tag_name, ranges), sections|
+      tag = tags_by_name[tag_name.to_s]
+      next if tag.nil?
+
+      sections[tag.id] = Array(ranges).map { |range| [range[0], range[1]] }
+    end
+  end
+
+  def sync_post_tags! post, desired_tags, sections
+    desired_ids = desired_tags.map(&:id).to_set
+    current_ids = post.tags.pluck(:id).to_set
+    Tag.where(id: desired_ids - current_ids).find_each do |tag|
+      PostTag.create_or_find_by!(post:, tag:, created_user: @actor)
+    end
+    PostTagSection.where(post_id: post.id).destroy_all
+    sections.each do |tag_id, ranges|
+      ranges.each do |begin_ms, end_ms|
+        PostTagSection.create!(post_id: post.id,
+                               tag_id:,
+                               begin_ms:,
+                               end_ms:)
+      end
+    end
+    PostTag.where(post_id: post.id,
+                  tag_id: (current_ids - desired_ids).to_a).kept.find_each do |post_tag|
+      post_tag.discard_by!(@actor)
+    end
+  end
+
+  def sync_parent_posts! post, ids
+    if ids.include?(post.id)
+      post.errors.add :parent_post_ids, '自分自身を親投稿にはできません．'
+      raise ActiveRecord::RecordInvalid, post
+    end
+    missing = ids - Post.where(id: ids).pluck(:id)
+    if missing.present?
+      post.errors.add :parent_post_ids, "存在しない親投稿 Id. があります: #{ missing.join(' ') }"
+      raise ActiveRecord::RecordInvalid, post
+    end
+    ids.each { |parent_post_id| PostImplication.create_or_find_by!(post:, parent_post_id:) }
+  end
+end