import { RouterDecision } from '@vpp/domain'
import type { EventEnvelope } from '@vpp/domain'
import { LlmUnavailable } from './llm.js'
import type { Runtime } from './runtime.js'
import { ENVELOPE_GATE_STEP_ID } from './workflows/proposal-lifecycle.js'
import type { ResumeDecision } from './workflows/proposal-lifecycle.js'

/**
 * Trigger service (docs/02 §1, docs/09 §1): three sources, one shape —
 * "instantiate template X with params Y".
 *   scheduled: cron entries (D-1 06:00 situation, 08:00 bid) — no LLM in the path
 *   event:     bus consumers with deterministic rules
 *   manual:    the router agent turns free text into a RouterDecision
 *              (a template id + params, never a new flow); on LLM outage the
 *              operator picks the template explicitly.
 * Approval is a resume on the lifecycle run (docs/09 §2).
 */
export interface ScheduleEntry {
  id: string
  /** 'HH:MM' Asia/Shanghai on D-1 */
  localTime: string
  workflow: 'dayAheadSituation' | 'dayAheadBid'
}

export const DEFAULT_SCHEDULE: ScheduleEntry[] = [
  { id: 'situation-0600', localTime: '06:00', workflow: 'dayAheadSituation' }, // docs/07 D-1 06:00
  { id: 'bid-0800', localTime: '08:00', workflow: 'dayAheadBid' }, // docs/07 D-1 08:00; window is OPEN-QUESTION A1
]

export const nextMarketDate = (nowIso: string): string => {
  const shanghai = new Date(new Date(nowIso).getTime() + 8 * 3_600_000)
  shanghai.setUTCDate(shanghai.getUTCDate() + 1)
  return shanghai.toISOString().slice(0, 10)
}

export class TriggerService {
  private timer: NodeJS.Timeout | null = null
  private readonly firedToday = new Set<string>()
  private readonly unsubscribe: Array<() => void> = []

  constructor(
    private readonly rt: Runtime,
    private readonly schedule: ScheduleEntry[] = DEFAULT_SCHEDULE,
  ) {}

  // ---- scheduled ---------------------------------------------------------

  /** Polls the clock; fires each entry once per local day. Deterministic, LLM-free. */
  startScheduler(pollMs = 30_000): void {
    if (this.timer) return
    this.timer = setInterval(() => void this.tick(), pollMs)
    this.timer.unref()
  }

  stop(): void {
    if (this.timer) clearInterval(this.timer)
    this.timer = null
    for (const u of this.unsubscribe) u()
  }

  async tick(nowIso = this.rt.ctx.clock()): Promise<string[]> {
    const local = new Date(new Date(nowIso).getTime() + 8 * 3_600_000)
    const hhmm = local.toISOString().slice(11, 16)
    const day = local.toISOString().slice(0, 10)
    const fired: string[] = []
    for (const entry of this.schedule) {
      const key = `${day}:${entry.id}`
      if (hhmm >= entry.localTime && !this.firedToday.has(key)) {
        this.firedToday.add(key)
        await this.startTemplate(entry.workflow, { market_date: nextMarketDate(nowIso) }, 'SCHEDULED', entry.id)
        fired.push(entry.id)
      }
    }
    return fired
  }

  // ---- event -------------------------------------------------------------

  /** Deterministic event rules. M3: a SituationPublished with EXTREME risk opens an abnormal-day case (docs/13 §1). */
  startEventConsumers(): void {
    this.unsubscribe.push(
      this.rt.ctx.events.subscribe('SituationPublished', (evt: EventEnvelope) => {
        const payload = evt.payload as { report: { market_date: string; risk_level: string; id: string } }
        if (payload.report.risk_level === 'EXTREME') {
          this.rt.ctx.caseDesk.open({
            id: this.rt.ctx.newId('case'),
            kind: 'ADHOC_ANALYSIS',
            objective: `Abnormal-day protocol review for ${payload.report.market_date} (situation ${payload.report.id})`,
            owner: 'user-ops-lead', // OPEN-QUESTION B8
            deadline: `${payload.report.market_date}T00:00:00Z`,
          })
        }
      }),
    )
  }

  // ---- manual ------------------------------------------------------------

  async route(message: string): Promise<RouterDecision> {
    const prompt = `Operator request: "${message}". Today (UTC) is ${this.rt.ctx.clock()}. Default market_date is ${nextMarketDate(this.rt.ctx.clock())}.`
    try {
      return await this.rt.ctx.llm.structured('router-agent', prompt, RouterDecision)
    } catch (e) {
      if (e instanceof LlmUnavailable) throw new LlmUnavailable('router needs an LLM; pick a template explicitly via startTemplate')
      throw e
    }
  }

  async manual(message: string): Promise<{ decision: RouterDecision; run_id: string | null }> {
    const decision = await this.route(message)
    if (decision.workflow_id === 'adhoc-analysis') return { decision, run_id: null }
    const run_id = await this.startTemplate(decision.workflow_id === 'day-ahead-bid' ? 'dayAheadBid' : 'dayAheadSituation', decision.params, 'MANUAL', 'router')
    return { decision, run_id }
  }

  async startTemplate(workflow: 'dayAheadSituation' | 'dayAheadBid', params: { market_date: string }, trigger: 'SCHEDULED' | 'EVENT' | 'MANUAL', source: string): Promise<string> {
    const wf = this.rt.mastra.getWorkflow(workflow)
    const run = await wf.createRun()
    this.rt.ctx.events.append({ event_type: 'WorkflowTriggered', payload: { workflow, params, trigger, source, run_id: run.runId }, correlation_id: run.runId })
    const result = await run.start({ inputData: params })
    this.rt.ctx.events.append({ event_type: 'WorkflowFinished', payload: { workflow, run_id: run.runId, status: result.status }, correlation_id: run.runId })
    if (result.status === 'failed') throw result.error
    return run.runId
  }

  // ---- approval = resume -------------------------------------------------

  async decide(runId: string, decision: ResumeDecision) {
    const wf = this.rt.mastra.getWorkflow('proposalLifecycle')
    const run = await wf.createRun({ runId })
    return run.resume({ step: ENVELOPE_GATE_STEP_ID, resumeData: decision })
  }
}