Function applyAppendedPromptSignals

src/screens/replMessageSignals.ts:199–239

(
  previous: PromptInputMessageSignals,
  appended: Message[],
)

}

function applyAppendedPromptSignals(
  previous: PromptInputMessageSignals,
  appended: Message[],
): PromptInputMessageSignals {
  if (appended.length === 0) {
    return previous
  }

  let lastAssistantMessageId = previous.lastAssistantMessageId
  let lastApiUsageKey = previous.lastApiUsageKey
  let hasAssistantMessages = previous.hasAssistantMessages

  for (const message of appended) {
    if (message?.type !== 'assistant') {
      continue
    }

    hasAssistantMessages = true
    lastAssistantMessageId = message.uuid

    const usage = getTokenUsage(message)
    if (!usage) {
      continue
    }

    lastApiUsageKey = [
      message.uuid,
      usage.input_tokens,
      usage.output_tokens,
      usage.cache_creation_input_tokens ?? 0,
      usage.cache_read_input_tokens ?? 0,
    ].join(':')
  }

  return {
    hasMessages: true,
    hasAssistantMessages,
    lastAssistantMessageId,
    lastApiUsageKey,
  }
}

function deriveLastAssistantToolUses(
  messages: Message[],