module RubyLLM::Providers::OpenRouter::Streaming

# File lib/ruby_llm/providers/openrouter/streaming.rb, line 14
def build_chunk(data)
  usage = data['usage'] || {}
  delta = data.dig('choices', 0, 'delta') || {}

  Chunk.new(
    role: :assistant,
    model_id: data['model'],
    content: delta['content'],
    thinking: Thinking.build(
      text: extract_thinking_text(delta),
      signature: extract_thinking_signature(delta)
    ),
    tool_calls: OpenAI::Tools.parse_tool_calls(delta['tool_calls'], parse_arguments: false),
    input_tokens: OpenRouter::Chat.input_tokens(usage),
    output_tokens: OpenRouter::Chat.output_tokens(usage),
    cached_tokens: OpenRouter::Chat.cache_read_tokens(usage),
    cache_creation_tokens: OpenRouter::Chat.cache_write_tokens(usage),
    thinking_tokens: OpenRouter::Chat.thinking_tokens(usage)
  )
end

# File lib/ruby_llm/providers/openrouter/streaming.rb, line 58
def extract_thinking_signature(delta)
  details = delta['reasoning_details']
  return nil unless details.is_a?(Array)

  signature = details.filter_map do |detail|
    detail['signature'] if detail['signature'].is_a?(String)
  end.first
  return signature if signature

  encrypted = details.find { |detail| detail['type'] == 'reasoning.encrypted' && detail['data'].is_a?(String) }
  encrypted&.dig('data')
end

# File lib/ruby_llm/providers/openrouter/streaming.rb, line 39
def extract_thinking_text(delta)
  candidate = delta['reasoning']
  return candidate if candidate.is_a?(String)

  details = delta['reasoning_details']
  return nil unless details.is_a?(Array)

  text = details.filter_map do |detail|
    case detail['type']
    when 'reasoning.text'
      detail['text']
    when 'reasoning.summary'
      detail['summary']
    end
  end.join

  text.empty? ? nil : text
end

# File lib/ruby_llm/providers/openrouter/streaming.rb, line 35
def parse_streaming_error(data)
  OpenAI::Streaming.parse_streaming_error(data)
end

# File lib/ruby_llm/providers/openrouter/streaming.rb, line 10
def stream_url
  completion_url
end