import { join } from 'node:path'
import { Mastra } from '@mastra/core'
import type { MastraModelConfig } from '@mastra/core/llm'
import { LibSQLStore } from '@mastra/libsql'
import { Approval, DecisionCase, Envelope, ExecutionPermit, ExecutionReceipt, Proposal, ResourceProfile } from '@vpp/domain'
import {
  AuthorityService,
  CaseDeskService,
  EnvelopeService,
  FileEventBus,
  FileExportGateway,
  FsRepository,
  FsSnapshotStore,
  HUBEI_BID_PACK_PLACEHOLDER,
  HttpSkillClient,
  LedgerService,
  LineageRecorder,
  MemoryTimeSeriesStore,
  PendingApprovalSchema,
  PolicyEngine,
  RevenueScenarioSimulator,
  hubeiSpotBiddingPack,
} from '@vpp/services'
import type { SkillClient } from '@vpp/services'
import type { RuntimeConfig, RuntimeContext } from './context.js'
import { AGENT_SPECS, MastraLlm, NullLlm } from './llm.js'
import type { LlmPort } from './llm.js'
import { createDayAheadBid } from './workflows/day-ahead-bid.js'
import { createDayAheadSituation } from './workflows/day-ahead-situation.js'
import { createProposalLifecycle } from './workflows/proposal-lifecycle.js'

/**
 * Runtime = thin shell over Mastra + the self-built services (docs/09 §0).
 * `createRuntime` wires storage, workflows and agents; everything durable
 * lives under `dataDir` so a second `createRuntime` on the same directory
 * *is* a process restart for the purposes of the resumability tests.
 */
export interface RuntimeOptions {
  dataDir: string
  /** Router model id (e.g. 'openai/gpt-...'), an OpenAI-compatible config, or an LlmPort for tests; null = LLM down. */
  llm: MastraModelConfig | LlmPort | null
  skills: SkillClient | string
  clock?: () => string
  config?: Partial<RuntimeConfig>
  /** Optional in-memory overrides for tests (time series is in-memory in phase 1 regardless). */
  timeseries?: RuntimeContext['timeseries']
}

export const DEFAULT_RUNTIME_CONFIG: RuntimeConfig = {
  policyPackId: 'hubei-spot-bidding',
  approverRoles: ['senior-trader', 'ops-lead', 'risk-officer'], // OPEN-QUESTION B3
  bidPermitTtlMs: 6 * 3_600_000, // OPEN-QUESTION A1
  risk: { risk_aversion: '0.3', commitment_buffer_k: '0.9', min_block_mwh: '0.5', marginal_cost_yuan_per_mwh: '0' }, // B6 / A6 / A4
  worstCaseLossBudgetYuan: '100000', // OPEN-QUESTION B5
  forecastWindowDays: 28,
  extremeDayPriceRatio: '2.0', // OPEN-QUESTION B7
  bidDeadlineLocal: '09:00', // OPEN-QUESTION A1
}

export interface Runtime {
  mastra: Mastra
  ctx: RuntimeContext
  close(): Promise<void>
}

const isLlmPort = (x: unknown): x is LlmPort => !!x && typeof x === 'object' && 'structured' in (x as object) && 'backend' in (x as object)

export async function createRuntime(opts: RuntimeOptions): Promise<Runtime> {
  const config = { ...DEFAULT_RUNTIME_CONFIG, ...opts.config }
  const clock = opts.clock ?? (() => new Date().toISOString())
  let seq = 0
  const newId = (prefix: string) => `${prefix}-${Date.now().toString(36)}-${(++seq).toString(36)}-${Math.random().toString(36).slice(2, 6)}`
  const dir = (name: string) => join(opts.dataDir, name)

  const snapshots = new FsSnapshotStore(dir('snapshots'))
  const events = new FileEventBus(dir('events.jsonl'), clock)
  const ledger = new LedgerService({ daMonthlyDeviationBand: '0.05', clock }) // OPEN-QUESTION A5
  const authority = new AuthorityService(new FsRepository(dir('permits.json'), ExecutionPermit, (p) => p.id, clock), () => newId('permit'))
  const policy = new PolicyEngine([hubeiSpotBiddingPack('2026.03', HUBEI_BID_PACK_PLACEHOLDER)])
  const envelopes = new EnvelopeService(new FsRepository(dir('envelopes.json'), Envelope, (e) => e.id, clock))
  const caseDesk = new CaseDeskService({
    cases: new FsRepository(dir('cases.json'), DecisionCase, (c) => c.id, clock),
    proposals: new FsRepository(dir('proposals.json'), Proposal, (p) => p.id, clock),
    approvals: new FsRepository(dir('approvals.json'), Approval, (a) => a.id, clock),
    pending: new FsRepository(dir('pending.json'), PendingApprovalSchema, (p) => p.proposal_id, clock),
    authority,
    snapshots,
    events,
    clock,
  })
  const gateway = new FileExportGateway(authority, dir('exports'), new FsRepository(dir('receipts.json'), ExecutionReceipt, (r) => r.idempotency_key, clock))

  let llm: LlmPort
  let agents: Record<string, never> | ReturnType<MastraLlm['mastraAgents']> = {}
  if (opts.llm === null) llm = new NullLlm()
  else if (isLlmPort(opts.llm)) llm = opts.llm
  else {
    const m = new MastraLlm(opts.llm, AGENT_SPECS)
    llm = m
    agents = m.mastraAgents()
  }

  const ctx: RuntimeContext = {
    config,
    clock,
    newId,
    snapshots,
    timeseries: opts.timeseries ?? new MemoryTimeSeriesStore(clock),
    resources: new FsRepository(dir('resources.json'), ResourceProfile, (r) => r.resource_id, clock),
    ledger,
    events,
    policy,
    envelopes,
    authority,
    gateway,
    simulation: new RevenueScenarioSimulator(),
    caseDesk,
    skills: typeof opts.skills === 'string' ? new HttpSkillClient(opts.skills) : opts.skills,
    lineage: new LineageRecorder(),
    llm,
  }

  const storage = new LibSQLStore({ id: 'vpp-runtime', url: `file:${dir('mastra.db')}` })
  // Workflows are built per runtime so their steps close over *this* context;
  // module-level singletons would bind to whichever Mastra registered last.
  const proposalLifecycle = createProposalLifecycle(ctx)
  const mastra = new Mastra({
    storage,
    workflows: { proposalLifecycle, dayAheadSituation: createDayAheadSituation(ctx), dayAheadBid: createDayAheadBid(ctx, proposalLifecycle) },
    agents,
  })
  return { mastra, ctx, close: () => storage.close() }
}