module AiContext

# File lib/ai/context.rb, line 52
def follow_up_question?(question)
  question.to_s.match?(PRONOUN_CONTEXT_PATTERN) ||
    question.to_s.match?(AI_FOLLOW_UP_PATTERN)
end

# File lib/ai/context.rb, line 46
def generic_joke_request?(question, stop_words: [])
  return false unless joke_request?(question)

  topical_tokens(question, stop_words: stop_words).empty?
end

# File lib/ai/context.rb, line 42
def joke_request?(question)
  question.to_s.match?(JOKE_REQUEST_PATTERN)
end

# File lib/ai/context.rb, line 122
def normalize_text(text)
  sanitize_log_text(text).downcase.gsub(/[^a-z0-9\s]/, " ").squeeze(" ").strip
end

# File lib/ai/context.rb, line 38
def own_message_question?(question)
  question.to_s.match?(OWN_MESSAGE_QUESTION_PATTERN)
end

# File lib/ai/context.rb, line 100
def query_tokens(question, stop_words: [])
  normalize_text(question).split.reject { |word| word.length < 3 || stop_words.include?(word) }
end

# File lib/ai/context.rb, line 57
def regular_context_channel_entries(entries)
  Array(entries).reject { |entry| entry[:is_command] || entry["is_command"] }
end

# File lib/ai/context.rb, line 113
def relevance_score(text, tokens)
  return 0 if tokens.empty?

  line_tokens = normalize_text(text).split
  tokens.count do |token|
    line_tokens.any? { |line_token| token_match?(line_token, token) }
  end
end

# File lib/ai/context.rb, line 126
def sanitize_log_text(text)
  text.to_s.gsub(/[\x00-\x1f]/, " ").squeeze(" ").strip
end

# File lib/ai/context.rb, line 61
def select_asker_entries(entries, asker, limit: PRONOUN_FALLBACK_LINES)
  nick = asker.to_s.strip
  return [] if nick.empty?

  regular_context_channel_entries(entries).select do |entry|
    entry_nick = (entry[:nick] || entry["nick"]).to_s
    entry_nick.casecmp?(nick)
  end.last(limit)
end

# File lib/ai/context.rb, line 71
def select_context_entries(entries, question, asker: nil, stop_words: [])
  return [] if entries.empty?

  if own_message_question?(question) && !asker.to_s.strip.empty?
    asker_entries = select_asker_entries(entries, asker, limit: 1)
    return asker_entries if asker_entries.any?
  end

  tokens = query_tokens(question, stop_words: stop_words)
  scored = entries.map { |entry| [entry, relevance_score(entry[:text] || entry["text"], tokens)] }

  if tokens.any?
    relevant = scored.select { |_entry, score| score.positive? }.map(&:first)
    return relevant.last(MAX_CONTEXT_LINES) if relevant.any?
  end

  return entries.last(PRONOUN_FALLBACK_LINES) if follow_up_question?(question)
  return regular_context_channel_entries(entries).last(PRONOUN_FALLBACK_LINES) if generic_joke_request?(
    question,
    stop_words: stop_words
  )

  []
end

# File lib/ai/context.rb, line 104
def token_match?(line_token, query_token)
  return true if line_token == query_token

  shorter, longer = [line_token, query_token].sort_by(&:length)
  return false if shorter.length < 3

  longer.start_with?(shorter)
end

# File lib/ai/context.rb, line 96
def topical_tokens(question, stop_words: [])
  query_tokens(question, stop_words: stop_words) - JOKE_FILLER_TOKENS
end