/* SPDX-License-Identifier: Apache-2.0 */
/* Host harness: replays a day of demand through the kernel with a modelled meter and writes an OER/2 vector file.
   The meter is a model of constants (a cycle count, standby and shared draws, a link energy), none measured on the
   node, so every figure is graded projected (oer-receipts §2: an Estimator figure), from a simulation, by a modelled
   method: the receipts never present the model as a reading. */
#include "settle.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static uint32_t rng_s = 42; static double urand(void){ rng_s = rng_s * 1664525u + 1013904223u; return (rng_s >> 8) / 16777216.0; }
int main(int argc, char **argv){
  const char *path = argc > 1 ? argv[1] : "firmware_vectors.json"; int n_events = argc > 2 ? atoi(argv[2]) : 400;
  static settle_ctx_t ctx; uint8_t seed[32]; int i; for (i = 0; i < 32; i++) seed[i] = (uint8_t)(i * 7 + 3);
  settle_init(&ctx, seed, 300.0, 86400.0);
  FILE *f = fopen(path, "w"); if (!f) return 1;
  char pk[65]; settle_pk_hex(&ctx, pk);
  fprintf(f, "{\"oer\":\"2.0\",\"draft\":\"0.1\",\"source\":\"settle kernel host harness, %d events\",\"keys\":{\"ed25519:bench-node-01\":\"%s\"},\"vectors\":[{\"name\":\"v10 firmware chain from the C kernel\",\"receipts\":[", n_events, pk);
  static char buf[4096]; double now = 0, last = 0, meter = 0; const double standby_w = 1.8e-3, shared_w = 0.06;
  for (i = 0; i < n_events; i++) {
    now += 20 + 80 * urand(); char cls = urand() < 0.34 ? 'A' : 'B';
    double z = urand(); uint32_t id = (uint32_t)(cls == 'A' ? 1 + 2999 * z * z * z : 1 + 399 * z * z * z);
    settle_meter_t m; m.compute_j = 120000.0 * ctx.cycle_j; m.movement_j = cls == 'A' ? 2.3e-6 : 0; m.idle_alloc_j = standby_w * (now - last); m.shared_alloc_j = shared_w * (now - last); m.upstream_j = 0;
    m.latency_s = cls == 'A' ? 0.019 : 0.0017; m.method = "model_estimated"; m.how = "projected"; m.device = "simulation"; m.weakest_how = "projected"; m.weakest_input = "wire_w";
    settle_result_t res; if (settle_decide(&ctx, cls, id, now, &m, buf, sizeof buf, &res)) { fprintf(stderr, "decide failed\n"); return 2; }
    meter += res.joules_total; last = now;
    fprintf(f, "%s%s", i ? "," : "", buf);
  }
  static char recbuf[1 << 20]; fprintf(f, "],\"records\":"); if (settle_records_json(&ctx, recbuf, sizeof recbuf)) { fprintf(stderr, "records overflow\n"); return 3; } fputs(recbuf, f);
  fprintf(f, ",\"ledger\":{\"meter_joules\":\"%.12e\",\"unallocated_joules\":\"0.000000e+00\",\"carried_forward_joules\":\"0.000000e+00\"},\"expected\":[]}]}\n", meter);
  fclose(f); fprintf(stderr, "wrote %s: %d receipts, modelled meter %.6f J (projected, not a reading)\n", path, n_events, meter);
  /* The kernel signs no grade its meter cannot support (oer-receipts §2), checked on every run, after the
     file is written: this harness's model graded measured, a grade outside the four and a weakest grade
     outside them are each refused (-3); the same figure graded measured by a meter that reads an
     instrument is taken, so the rule is not a refusal of every measured figure. */
  {
    static const struct { const char *method, *how, *device, *weakest_how; int want; } cases[] = {
      { "model_estimated", "measured",  "simulation", "projected", -3 },
      { "model_estimated", "estimated", "simulation", "projected", -3 },
      { "model_estimated", "projected", "simulation", "estimated", -3 },
      { "hardware_meter",  "measured",  "hardware",   "projected",  0 },
    };
    for (i = 0; i < 4; i++) {
      settle_meter_t m = { .compute_j = 1e-3, .latency_s = 0.001, .method = cases[i].method, .how = cases[i].how, .device = cases[i].device, .weakest_how = cases[i].weakest_how, .weakest_input = "wire_w" };
      settle_result_t res; int rc = settle_decide(&ctx, 'A', 1, now + 1 + i, &m, buf, sizeof buf, &res);
      if (rc != cases[i].want) { fprintf(stderr, "a meter by %s graded %s (weakest %s): settle_decide gave %d, not %d\n", cases[i].method, cases[i].how, cases[i].weakest_how, rc, cases[i].want); return 4; }
    }
    fprintf(stderr, "a grade the meter cannot support: refused in 3 of 3 cases; a measured figure from an instrument's meter taken\n");
  }
  return 0;
}