// Risk score (docs/ARCHITECTURE.md §3.4): logistic regression over Jev's evidence answers.
// Weights are fit offline by training/train_scorer.ts and promoted only when the replay gate passes
// (zero legit calls quarantined on held-out data).

import type { Evidence } from './jev.ts';
import trained from './scorer-weights.json' with { type: 'json' };

export const SCORER_VERSION = trained.version;
/** Quarantine threshold chosen by training: the lowest that held back no legit example, plus a margin. */
export const SCORER_TAU = trained.tau;

export interface CallContext {
  stir: string | null;
  repeatsFromNumber7d: number;
}

export function pJunk(e: Evidence, ctx: CallContext): number {
  const w = trained.weights;
  const z =
    trained.bias +
    w.sales * e.sales +
    w.pressure * e.pressure +
    w.agent * e.agent +
    w.selfAssert * e.selfAssert +
    w.catJunk * (e.catScam + e.catMkt) +
    w.catLegit * e.catLegit +
    w.specific * e.specific +
    w.official * e.official +
    w.protected * e.protected +
    trained.handSet.stirC * (ctx.stir === 'TN-Validation-Passed-C' ? 1 : 0) +
    trained.handSet.repeat * Math.min(ctx.repeatsFromNumber7d, 4);
  return 1 / (1 + Math.exp(-z));
}