#!/usr/bin/env node
/**
 * sim-usdm-controller.mjs — simulator for the five-layer USDm controller
 * (snapshot 0147, §12 of usdm_complete-design_FOR-design-record.md).
 *
 * Walks the controller through 5 scenarios so the dynamics become concrete:
 *   1. Calm growth   — flat BCH, steady minting
 *   2. Sustained rally  — BCH +100% over 6 months
 *   3. Sustained crash  — BCH -50% over 6 months
 *   4. Flash crash + recovery — BCH -50% then back in 1 week
 *   5. Adoption boom  — BCH stable, rapid minting (many catalyst events)
 *
 * For each scenario it prints the controller's response across the timeline
 * and a summary showing how the five layers interact.
 *
 * Run: node scripts/sim-usdm-controller.mjs
 */

// ── Controller constants ────────────────────────────────────────────────
const BLOCK_MIN = 10;                 // one block ≈ 10 minutes
const RETARGET_BLOCKS = 2016;         // ~2 weeks
const TIME_DOUBLING_BLOCKS = 210_000; // ~4 years per doubling
const SUPPLY_CATALYST = 210_000;      // 210k cumulative minted per catalyst

// Per-direction bounds (asymptotic targets reached via catalysts)
const N_FLOOR = 1;
const N_CEILING = 144;
const D_FLOOR = 0.05;
const D_CEILING = 0.20;

// Catalyst step sizes
const N_STEP = 1;
const D_STEP = 0.005;

// DART time-trigger weights and max step
const W_PRICE = 1.0;
const W_FLOW = 0.5;
const W_SUPPLY = 0.5;
const K_MAX = 5;

// Deadband + cap (Layer 5, simplified — real controller has more)
const DEADBAND_BPS = 50;  // 0.5%
const CAP_BPS = 1000;     // 10% max single step

// ── Controller state ────────────────────────────────────────────────────
class Controller {
  constructor() {
    this.rate = 200_000;     // sats per $1 USDm (BCH = $500)
    this.N_up = 1;           // cadence multiplier rally side
    this.N_down = 1;         // cadence multiplier crash side
    this.d_up = 0.10;
    this.d_down = 0.10;
    this.doubling_epoch = 0; // Layer 3
    this.catalyst_count = 0; // Layer 2 sub-trigger count
    this.last_recal_block = 0;
    this.last_retarget_block = 0;
    this.cumulative_minted = 0;
    // For DART time-trigger signals collected over window:
    this.window_mints = 0;
    this.window_redeems = 0;
    this.window_rate_moves = 0;     // net direction over window
    this.window_supply_start = 0;
    this.prev_window_growth = 0;    // for velocity comparison
  }

  // Effective cadence (in blocks) for a direction, accounting for time-doubling
  cadenceBlocks(direction) {
    const N = direction === 'down' ? this.N_down : this.N_up;
    return N * Math.pow(2, this.doubling_epoch); // each N already represents 10-min units (= 1 block); doubling adds 2^epoch
  }

  // Step: process one block
  step(block, bch_price_usd, mints, redeems) {
    this.cumulative_minted += mints;
    this.window_mints += mints;
    this.window_redeems += redeems;

    // Layer 3 — time-doubling check
    const expected_epoch = Math.floor(block / TIME_DOUBLING_BLOCKS);
    if (expected_epoch > this.doubling_epoch) this.doubling_epoch = expected_epoch;

    // Layer 2 sub-trigger — supply catalyst (every 210k minted)
    const expected_catalysts = Math.floor(this.cumulative_minted / SUPPLY_CATALYST);
    while (expected_catalysts > this.catalyst_count) {
      this.catalyst_count += 1;
      this.applyCatalyst();
    }

    // Layer 2 main — DART time trigger (every 2016 blocks)
    if (block - this.last_retarget_block >= RETARGET_BLOCKS) {
      this.applyRetarget();
      this.last_retarget_block = block;
      this.window_mints = 0;
      this.window_redeems = 0;
      this.window_rate_moves = 0;
      this.prev_window_growth = this.cumulative_minted - this.window_supply_start;
      this.window_supply_start = this.cumulative_minted;
    }

    // Recalibration check
    const target = oracleTarget(bch_price_usd);
    const direction = target > this.rate ? 'down' : 'up';
    const cadence = this.cadenceBlocks(direction);
    if (block - this.last_recal_block >= cadence) {
      const gap = target - this.rate;
      const gapBps = Math.abs((gap / this.rate) * 10000);
      if (gapBps >= DEADBAND_BPS) {
        const d = direction === 'down' ? this.d_down : this.d_up;
        let delta = gap * d;
        // Layer 5 — cap
        const max_delta = (this.rate * CAP_BPS) / 10000;
        delta = Math.sign(delta) * Math.min(Math.abs(delta), max_delta);
        this.rate = Math.round(this.rate + delta);
        this.last_recal_block = block;
        this.window_rate_moves += direction === 'down' ? 1 : -1;
      }
    }
  }

  // Layer 2 sub — supply catalyst applied
  applyCatalyst() {
    this.N_down = Math.min(this.N_down + N_STEP, N_CEILING);
    this.N_up = Math.max(this.N_up - N_STEP, N_FLOOR);
    this.d_down = Math.max(this.d_down - D_STEP, D_FLOOR);
    this.d_up = Math.min(this.d_up + D_STEP, D_CEILING);
  }

  // Layer 2 main — DART time-trigger
  applyRetarget() {
    // Compute signals from window observations
    const net_dir = Math.sign(this.window_rate_moves); // -1 = predominantly rally, +1 = predominantly crash, 0 = neutral
    const flow_ratio = this.window_mints / Math.max(this.window_redeems, 1);
    const window_growth = this.cumulative_minted - this.window_supply_start;
    const growth_accel = this.prev_window_growth > 0 ? window_growth / this.prev_window_growth : 1.0;

    // Quantize each signal to ±{0,1,2,3} based on strength
    const ds = (raw, t1, t2, t3) =>
      raw === 0 ? 0 : Math.sign(raw) * (Math.abs(raw) >= t3 ? 3 : Math.abs(raw) >= t2 ? 2 : Math.abs(raw) >= t1 ? 1 : 0);

    const dprice = ds(net_dir * 3, 1, 2, 3); // net_dir already ±1
    const dflow = ds(flow_ratio - 1, 0.2, 1.0, 5.0) * (flow_ratio > 1 ? 1 : -1);
    const dsupply = ds(growth_accel - 1, 0.1, 1.0, 4.0) * (growth_accel > 1 ? 1 : -1);

    // Per the design record §12a.1 sign rules per direction
    // Sustained crash (dprice > 0) → increase N_down (slower crash; positive)
    // Sustained rally (dprice < 0) → decrease N_up (faster rally; negative)
    // Net flow: mint>redeem → both N's increase; redeem>mint → both N's decrease
    // Supply weak → N_up up, N_down down; supply strong → both N's down

    let sign_up_price = dprice < 0 ? dprice : 0;     // rally (negative dprice) → reduce N_up (also negative)
    let sign_down_price = dprice > 0 ? dprice : 0;   // crash (positive dprice) → increase N_down (positive)

    let sign_up_flow = dflow;        // direct
    let sign_down_flow = dflow;      // direct

    let sign_up_supply = -dsupply;            // weak (negative dsupply) → positive (raise N_up); strong → negative (reduce N_up)
    let sign_down_supply = -Math.abs(dsupply); // weak and strong both reduce N_down (signal magnitude only, always negative)

    // Sum with weights + clamp
    const sum_up = W_PRICE * sign_up_price + W_FLOW * sign_up_flow + W_SUPPLY * sign_up_supply;
    const sum_down = W_PRICE * sign_down_price + W_FLOW * sign_down_flow + W_SUPPLY * sign_down_supply;

    const delta_up = Math.max(-K_MAX, Math.min(K_MAX, Math.round(sum_up)));
    const delta_down = Math.max(-K_MAX, Math.min(K_MAX, Math.round(sum_down)));

    // Apply
    this.N_up = Math.max(N_FLOOR, Math.min(N_CEILING, this.N_up + delta_up));
    this.N_down = Math.max(N_FLOOR, Math.min(N_CEILING, this.N_down + delta_down));
  }
}

// Oracle target: sats per $1 from BCH price in USD
function oracleTarget(bch_usd) {
  return Math.round((100_000_000 / bch_usd));
}

// Format helpers
const fmt = {
  rate: (r) => `${r.toLocaleString().padStart(7)} sats/$`,
  pct: (n) => `${(n * 100).toFixed(1)}%`,
  bch: (p) => `$${p.toFixed(0)}`,
};

// ── Scenario runner ─────────────────────────────────────────────────────
function runScenario(name, description, priceFn, mintFn, redeemFn, blocks) {
  console.log(`\n${'═'.repeat(72)}`);
  console.log(`  ${name}`);
  console.log(`  ${description}`);
  console.log('═'.repeat(72));

  const c = new Controller();
  const snapshots = [];
  const checkpoints = [0, 0.05, 0.15, 0.30, 0.50, 0.75, 1.0].map((f) => Math.floor(f * blocks));

  for (let block = 0; block < blocks; block++) {
    const bch_price = priceFn(block, blocks);
    const mints = mintFn(block, blocks);
    const redeems = redeemFn(block, blocks);
    c.step(block, bch_price, mints, redeems);
    if (checkpoints.includes(block)) {
      snapshots.push({
        block, bch_price,
        rate: c.rate, target: oracleTarget(bch_price),
        N_up: c.N_up, N_down: c.N_down,
        d_up: c.d_up, d_down: c.d_down,
        catalysts: c.catalyst_count, doubling: c.doubling_epoch,
        minted: c.cumulative_minted,
      });
    }
  }

  // Final snapshot
  const finalPrice = priceFn(blocks - 1, blocks);
  snapshots.push({
    block: blocks - 1, bch_price: finalPrice,
    rate: c.rate, target: oracleTarget(finalPrice),
    N_up: c.N_up, N_down: c.N_down,
    d_up: c.d_up, d_down: c.d_down,
    catalysts: c.catalyst_count, doubling: c.doubling_epoch,
    minted: c.cumulative_minted,
  });

  // Print trajectory
  console.log(`\n  ${'Block'.padEnd(8)} ${'BCH'.padStart(6)} ${'oracle$/rate'.padStart(14)} ${'controller rate'.padStart(16)} ${'gap%'.padStart(7)} ${'N↑'.padStart(4)} ${'N↓'.padStart(4)} ${'d↑'.padStart(5)} ${'d↓'.padStart(5)} ${'catalysts'.padStart(10)}`);
  console.log(`  ${'-'.repeat(105)}`);
  for (const s of snapshots) {
    const gap = ((s.rate - s.target) / s.target) * 100;
    console.log(
      `  ${String(s.block).padEnd(8)} ${fmt.bch(s.bch_price).padStart(6)} ${s.target.toLocaleString().padStart(14)} ${s.rate.toLocaleString().padStart(16)} ${gap.toFixed(1).padStart(6)}% ${String(s.N_up).padStart(4)} ${String(s.N_down).padStart(4)} ${(s.d_up * 100).toFixed(1).padStart(4)}% ${(s.d_down * 100).toFixed(1).padStart(4)}% ${String(s.catalysts).padStart(10)}`
    );
  }

  const final = snapshots[snapshots.length - 1];
  const finalGap = ((final.rate - final.target) / final.target) * 100;
  console.log(`\n  Summary: rate vs oracle target gap at end = ${finalGap >= 0 ? '+' : ''}${finalGap.toFixed(1)}%`);
  console.log(`  Asymmetric bias: N_down/N_up = ${(final.N_down / final.N_up).toFixed(1)}x  ·  d_up/d_down = ${(final.d_up / final.d_down).toFixed(2)}x`);
  console.log(`  Total catalysts fired: ${final.catalysts}  ·  doubling regime: ${final.doubling}  ·  cumulative minted: ${final.minted.toLocaleString()}`);
}

// ── Scenarios ───────────────────────────────────────────────────────────
const ONE_DAY = 144;             // blocks
const ONE_WEEK = 7 * ONE_DAY;
const SIX_MONTHS = 26 * ONE_WEEK;
const TWO_YEARS = 104 * ONE_WEEK;

runScenario(
  'SCENARIO 1 — Calm growth',
  'BCH stable at $500; steady minting (50 units/block ≈ 7,200/day)',
  () => 500,
  () => 50,
  () => 5,
  SIX_MONTHS,
);

runScenario(
  'SCENARIO 2 — Sustained rally',
  'BCH climbs $500 → $1000 over 6 months; moderate minting + redemption pickup',
  (b, total) => 500 + (500 * b) / total,
  (b, total) => 30 + (50 * b) / total,  // minting picks up toward end
  (b, total) => 5 + (15 * b) / total,   // redemption also rises
  SIX_MONTHS,
);

runScenario(
  'SCENARIO 3 — Sustained crash',
  'BCH falls $500 → $250 over 6 months; mints climb (bargain buying), redeems flat',
  (b, total) => 500 - (250 * b) / total,
  (b, total) => 30 + (40 * b) / total,
  () => 5,
  SIX_MONTHS,
);

runScenario(
  'SCENARIO 4 — Flash crash + recovery',
  'BCH at $500, drops to $250 over 3 days, recovers over 4 days; normal flows',
  (b) => {
    if (b < 3 * ONE_DAY) return 500 - (250 * b) / (3 * ONE_DAY);
    if (b < 7 * ONE_DAY) return 250 + (250 * (b - 3 * ONE_DAY)) / (4 * ONE_DAY);
    return 500;
  },
  () => 50,
  () => 5,
  ONE_WEEK * 2,  // 2 weeks to see the recovery + 1 week post
);

runScenario(
  'SCENARIO 5 — Adoption boom (many catalysts)',
  'BCH stable at $500; minting rapidly increases (50 → 500 units/block); many 210k catalysts fire',
  () => 500,
  (b, total) => 50 + (450 * b) / total,
  () => 5,
  SIX_MONTHS,
);

console.log(`\n${'═'.repeat(72)}`);
console.log('  All scenarios complete. Observe:');
console.log('  - Scenario 1: controller stays calm; no catalysts due to low minting');
console.log('  - Scenario 2: rate moves up gradually; up-side cadence reduces from DART signals');
console.log('  - Scenario 3: rate lag widens; mint-favored arbitrage opportunity emerges');
console.log('  - Scenario 4: rate barely moves during flash event; full recovery without trace');
console.log('  - Scenario 5: many catalysts fire; asymmetric bias accumulates rapidly');
console.log('═'.repeat(72));