class RubyLsp::ResponseBuilders::SemanticHighlighting::SemanticTokenEncoder

# File lib/ruby_lsp/response_builders/semantic_highlighting.rb, line 157
def initialize
  @current_row = T.let(0, Integer)
  @current_column = T.let(0, Integer)
end

# File lib/ruby_lsp/response_builders/semantic_highlighting.rb, line 192
def compute_delta(token)
  row = token.start_line - 1
  column = token.start_code_unit_column

  begin
    delta_line = row - @current_row

    delta_column = column
    delta_column -= @current_column if delta_line == 0

    [delta_line, delta_column, token.length, token.type, encode_modifiers(token.modifier)]
  ensure
    @current_row = row
    @current_column = column
  end
end

# File lib/ruby_lsp/response_builders/semantic_highlighting.rb, line 167
def encode(tokens)
  sorted_tokens = tokens.sort_by.with_index do |token, index|
    # Enumerable#sort_by is not deterministic when the compared values are equal.
    # When that happens, we need to use the index as a tie breaker to ensure
    # that the order of the tokens is always the same.
    [token.start_line, token.start_code_unit_column, index]
  end

  delta = sorted_tokens.flat_map do |token|
    compute_delta(token)
  end

  Interface::SemanticTokens.new(data: delta)
end

# File lib/ruby_lsp/response_builders/semantic_highlighting.rb, line 214
def encode_modifiers(modifiers)
  modifiers.inject(0) do |encoded_modifiers, modifier|
    encoded_modifiers | (1 << modifier)
  end
end