discourse-ai/lib/ai_helper/semantic_categorizer.rb

108 lines
3.3 KiB
Ruby

# frozen_string_literal: true
module DiscourseAi
module AiHelper
class SemanticCategorizer
def initialize(input, user)
@user = user
@text = input[:text]
end
def categories
return [] if @text.blank?
return [] unless SiteSetting.ai_embeddings_enabled
candidates = nearest_neighbors(limit: 100)
candidate_ids = candidates.map(&:first)
::Topic
.joins(:category)
.where(id: candidate_ids)
.where("categories.id IN (?)", Category.topic_create_allowed(@user.guardian).pluck(:id))
.order("array_position(ARRAY#{candidate_ids}, topics.id)")
.pluck(
"categories.id",
"categories.name",
"categories.slug",
"categories.color",
"categories.topic_count",
)
.map
.with_index do |(id, name, slug, color, topic_count), index|
{
id: id,
name: name,
slug: slug,
color: color,
topicCount: topic_count,
score: candidates[index].last,
}
end
.map do |c|
c[:score] = 1 / (c[:score] + 1) # inverse of the distance
c
end
.group_by { |c| c[:name] }
.map { |name, scores| scores.first.merge(score: scores.sum { |s| s[:score] }) }
.sort_by { |c| -c[:score] }
.take(5)
end
def tags
return [] if @text.blank?
return [] unless SiteSetting.ai_embeddings_enabled
candidates = nearest_neighbors(limit: 100)
candidate_ids = candidates.map(&:first)
count_column = Tag.topic_count_column(@user.guardian) # Determine the count column
::Topic
.joins(:topic_tags, :tags)
.where(id: candidate_ids)
.where("tags.id IN (?)", DiscourseTagging.visible_tags(@user.guardian).pluck(:id))
.group("topics.id, tags.id, tags.name") # Group by topics.id and tags.id
.order("array_position(ARRAY#{candidate_ids}, topics.id)")
.pluck(
"tags.id",
"tags.name",
"tags.#{count_column}",
"MIN(array_position(ARRAY#{candidate_ids}, topics.id))", # Get minimum index for ordering
)
.uniq # Ensure unique tags per topic
.map
.with_index do |(id, name, count, index), idx|
{
id: id,
name: name,
count: count,
score: 1 / (candidates[idx].last + 1), # Inverse of the distance for score
}
end
.group_by { |tag| tag[:name] }
.map do |name, tags|
tags.first.merge(score: tags.sum { |t| t[:score] })
end # Aggregate scores per tag
.sort_by { |tag| -tag[:score] }
.take(5)
end
private
def nearest_neighbors(limit: 100)
strategy = DiscourseAi::Embeddings::Strategies::Truncation.new
vector_rep =
DiscourseAi::Embeddings::VectorRepresentations::Base.current_representation(strategy)
raw_vector = vector_rep.vector_from(@text)
vector_rep.asymmetric_topics_similarity_search(
raw_vector,
limit: limit,
offset: 0,
return_distance: true,
)
end
end
end
end