import { ORPCError } from '@orpc/client'
import type { MarketClient } from './client.js'
import type { AgentResult } from './schemas.js'

export class AgentError extends Error {
  constructor(message: string) {
    super(message)
    this.name = 'AgentError'
  }
}

export interface AgentInput {
  goal: string
  /** Reference images, each an http(s) URL or a data:image URI. */
  referenceImages?: string[]
}

// The server bounds a run well under this; it only guards against a run that
// never settles at all.
const RUN_TIMEOUT_MS = 5 * 60 * 1000

/**
 * Start an agent run and wait for its result. `status` long-polls — it blocks
 * server-side until the run settles or a heartbeat window elapses — so we
 * re-request immediately with no client-side delay and no polling interval.
 */
export async function agentAndWait(client: MarketClient, input: AgentInput): Promise<AgentResult> {
  const { runId } = await client.asset.agent.start(input)
  const deadline = Date.now() + RUN_TIMEOUT_MS
  for (;;) {
    const status = await pollStatus(client, runId)
    if (status.status === 'completed') return status.result
    if (status.status === 'failed') throw new AgentError(status.error)
    if (Date.now() > deadline) throw new AgentError('Agent run timed out')
  }
}

async function pollStatus(client: MarketClient, runId: string) {
  try {
    return await client.asset.agent.status({ runId })
  } catch (error) {
    // Runs live only in worker memory; a 404 for a run we just started means the
    // worker restarted mid-run and the run is gone.
    if (error instanceof ORPCError && error.status === 404) {
      throw new AgentError('Agent run was interrupted by a server restart; run it again.')
    }
    throw error
  }
}