import type { UIMessage } from 'ai'

export interface PendingPascalAgentRun {
  conversationId: string
  startedAt: number
  userMessageId: string
}

export function parsePendingPascalAgentRun(value: string | null): PendingPascalAgentRun | null {
  if (!value) return null
  try {
    const parsed = JSON.parse(value) as Partial<PendingPascalAgentRun>
    if (
      typeof parsed.conversationId !== 'string' ||
      typeof parsed.startedAt !== 'number' ||
      typeof parsed.userMessageId !== 'string'
    ) {
      return null
    }
    return parsed as PendingPascalAgentRun
  } catch {
    return null
  }
}

export function hasCompletedPascalAgentResponse(
  messages: UIMessage[],
  userMessageId: string,
): boolean {
  const userIndex = messages.findIndex(
    (message) => message.id === userMessageId && message.role === 'user',
  )
  if (userIndex < 0) return false

  return messages.slice(userIndex + 1).some(
    (message) =>
      message.role === 'assistant' &&
      message.parts.some((part) => {
        if (part.type === 'text') return Boolean(part.text.trim())
        if (part.type === 'data-pascal-tool-activity') {
          const state = (part.data as { state?: unknown } | undefined)?.state
          return state === 'output-available' || state === 'output-error'
        }
        if (part.type.startsWith('tool-')) {
          const state = (part as { state?: unknown }).state
          return state === 'output-available' || state === 'output-error'
        }
        return false
      }),
  )
}