Add IEC62056 parsing, OLED timing, and batch LoRa send

src/json_codec.cpp

@@ -59,3 +59,90 @@ bool jsonToMeterData(const String &json, MeterData &data) {
 
   return true;
 }
+
+bool meterBatchToJson(const MeterData *samples, size_t count, String &out_json) {
+  if (!samples || count == 0) {
+    return false;
+  }
+
+  DynamicJsonDocument doc(8192);
+  doc["id"] = samples[count - 1].device_id;
+  doc["bat_v"] = samples[count - 1].battery_voltage_v;
+  doc["bat_pct"] = samples[count - 1].battery_percent;
+  JsonArray arr = doc.createNestedArray("s");
+  for (size_t i = 0; i < count; ++i) {
+    JsonArray row = arr.createNestedArray();
+    row.add(samples[i].ts_utc);
+    row.add(samples[i].energy_total_kwh);
+    row.add(samples[i].total_power_w);
+    row.add(samples[i].phase_power_w[0]);
+    row.add(samples[i].phase_power_w[1]);
+    row.add(samples[i].phase_power_w[2]);
+    row.add(samples[i].phase_voltage_v[0]);
+    row.add(samples[i].phase_voltage_v[1]);
+    row.add(samples[i].phase_voltage_v[2]);
+    row.add(samples[i].valid ? 1 : 0);
+  }
+
+  out_json = "";
+  size_t len = serializeJson(doc, out_json);
+  return len > 0;
+}
+
+bool jsonToMeterBatch(const String &json, MeterData *out_samples, size_t max_count, size_t &out_count) {
+  out_count = 0;
+  if (!out_samples || max_count == 0) {
+    return false;
+  }
+
+  DynamicJsonDocument doc(8192);
+  DeserializationError err = deserializeJson(doc, json);
+  if (err) {
+    return false;
+  }
+
+  JsonArray arr = doc["s"].as<JsonArray>();
+  if (arr.isNull()) {
+    return false;
+  }
+
+  const char *id = doc["id"] | "";
+  float bat_v = doc["bat_v"] | NAN;
+  uint8_t bat_pct = doc["bat_pct"] | 0;
+
+  size_t idx = 0;
+  for (JsonArray row : arr) {
+    if (idx >= max_count) {
+      break;
+    }
+    MeterData &data = out_samples[idx];
+    data = {};
+    strncpy(data.device_id, id, sizeof(data.device_id));
+    data.device_id[sizeof(data.device_id) - 1] = '\0';
+    data.ts_utc = row[0] | 0;
+    data.energy_total_kwh = row[1] | NAN;
+    data.total_power_w = row[2] | NAN;
+    data.phase_power_w[0] = row[3] | NAN;
+    data.phase_power_w[1] = row[4] | NAN;
+    data.phase_power_w[2] = row[5] | NAN;
+    data.phase_voltage_v[0] = row[6] | NAN;
+    data.phase_voltage_v[1] = row[7] | NAN;
+    data.phase_voltage_v[2] = row[8] | NAN;
+    data.valid = (row[9] | 1) != 0;
+    data.battery_voltage_v = bat_v;
+    if (doc["bat_pct"].isNull() && !isnan(bat_v)) {
+      data.battery_percent = battery_percent_from_voltage(bat_v);
+    } else {
+      data.battery_percent = bat_pct;
+    }
+
+    if (strlen(data.device_id) >= 8) {
+      const char *suffix = data.device_id + strlen(data.device_id) - 4;
+      data.short_id = static_cast<uint16_t>(strtoul(suffix, nullptr, 16));
+    }
+    idx++;
+  }
+
+  out_count = idx;
+  return idx > 0;
+}