import { fileURLToPath } from 'node:url'
import { describe, expect, it } from 'vitest'
import type {
  BidOptimizationRequest,
  BidOptimizationResult,
  ForecastBundle,
  ForecastKind,
  ForecastRequest,
  ReportRequest,
  SkillReport,
} from '@vpp/domain'
import type { SkillClient } from '@vpp/services'
import { loadDataset } from '../src/dataset.js'
import { DEFAULT_CONFIG, runL2 } from '../src/harness.js'

const datasetPath = fileURLToPath(new URL('../datasets/synthetic-hubei-v0.json', import.meta.url))

/**
 * Stub skills with trivially checkable behaviour: forecast = last history
 * day ± 10%; bid = flat quantity hitting the lower energy bound at offer 0.
 * Lets the harness itself be tested without the Python service running.
 */
class StubClient implements SkillClient {
  calls = 0
  async skills() {
    return [
      { id: 'load-forecast', version: '0.0.1', endpoint: '/stub' },
      { id: 'bid-optimization-milp', version: '0.0.1', endpoint: '/stub' },
    ]
  }
  async forecast(kind: ForecastKind, req: ForecastRequest): Promise<ForecastBundle> {
    this.calls++
    const last = req.history[req.history.length - 1]!
    const scaled = (f: number) => ({
      interval_minutes: 15 as const,
      date: req.market_date,
      values: last.values.map((v) => (Number(v) * f).toFixed(3)),
    })
    return {
      id: `stub-${kind}`,
      kind,
      market_date: req.market_date,
      unit: req.unit,
      quantiles: { p10: scaled(0.9), p50: scaled(1), p90: scaled(1.1) },
      model: { name: 'stub', version: '0.0.1' },
      features_snapshot_ref: req.features_snapshot_ref,
      generated_at: '2026-01-01T00:00:00Z',
    }
  }
  async optimizeBid(req: BidOptimizationRequest): Promise<BidOptimizationResult> {
    this.calls++
    const per = (Number(req.position_bounds.daily_energy_min_mwh) / 96).toFixed(3)
    const flat = { interval_minutes: 15 as const, date: req.market_date, values: Array(96).fill(per) as string[] }
    const energy = (Number(per) * 96).toFixed(3)
    return {
      market_date: req.market_date,
      prices_yuan_per_mwh: { ...flat, values: Array(96).fill('0.00') },
      quantities_mwh: flat,
      daily_energy_mwh: energy,
      expected_revenue_yuan: '0.00',
      revenue_distribution_yuan: { p10: '0.00', p50: '0.00', p90: '0.00' },
      position_bounds: req.position_bounds,
      solver: { name: 'stub', version: '0', status: 'OPTIMAL', objective_value: '0.00', wall_time_ms: 0 },
      binding_constraints: ['daily_energy_min'],
      skill_version: '0.0.1',
    }
  }
  async report(_req: ReportRequest): Promise<SkillReport> {
    throw new Error('not used')
  }
  async assessPotential(): Promise<never> {
    throw new Error('not used')
  }
  async optimizeDispatch(): Promise<never> {
    throw new Error('not used')
  }
}

const cfg = { ...DEFAULT_CONFIG, window: 7, holdoutFrom: 10, holdoutDays: 5 }

describe('L2 harness', () => {
  it('scores every held-out day and pushes each bid through the real ledger', async () => {
    const { dataset, sha256 } = loadDataset(datasetPath)
    const client = new StubClient()
    const run = await runL2(dataset, sha256, client, cfg, () => '2026-09-01T00:00:00Z')
    expect(run.per_day).toHaveLength(5)
    expect(client.calls).toBe(5 * 4)
    expect(run.metrics.bid.optimal_days).toBe(5)
    expect(run.metrics.bid.ledger_accepted_days).toBe(5) // stub bids sit exactly on the lower bound
    expect(run.metrics.load.coverage_p10_p90).toBeGreaterThan(0)
    expect(run.metrics.price.direction_accuracy).toBeGreaterThan(0.5) // yesterday's shape is informative
    expect(run.metrics.bid.revenue_hindsight_yuan).toBeGreaterThanOrEqual(run.metrics.bid.revenue_skill_yuan)
    expect(run.metrics.bid.revenue_hindsight_yuan).toBeGreaterThanOrEqual(run.metrics.bid.revenue_naive_yuan)
    expect(run.skill_versions['load-forecast']).toBe('0.0.1')
    expect(run.dataset.synthetic).toBe(true)
  })

  it('is reproducible: same inputs → same digest, independent of run time', async () => {
    const { dataset, sha256 } = loadDataset(datasetPath)
    const a = await runL2(dataset, sha256, new StubClient(), cfg, () => '2026-09-01T00:00:00Z')
    const b = await runL2(dataset, sha256, new StubClient(), cfg, () => '2026-09-02T00:00:00Z')
    expect(a.digest).toBe(b.digest)
    expect(a.id).not.toBe(b.id)
  })

  it('rejects a holdout that starts before the window is filled', async () => {
    const { dataset, sha256 } = loadDataset(datasetPath)
    await expect(runL2(dataset, sha256, new StubClient(), { ...cfg, holdoutFrom: 3 })).rejects.toThrow(/window/)
  })
})