Add esp32s2 support

esp32/main/protocol.cpp

@@ -1,52 +1,123 @@
 #include "protocol.h"
-#include "cJSON.h"
+#include <stdio.h>
+#include <stdarg.h>
 
-cJSON* protocol_message_to_json(const ProtocolMessage* msg) {
-    cJSON* root = cJSON_CreateObject();
+#define PROTOCOL_VERSION 1
 
-    cJSON_AddNumberToObject(root, "v", msg->v);
-    cJSON_AddStringToObject(root, "id", msg->id.c_str());
-    cJSON_AddStringToObject(root, "type", msg->type.c_str());
-    cJSON_AddNumberToObject(root, "ts", msg->ts);
-    cJSON_AddStringToObject(root, "deviceId", msg->deviceId.c_str());
+static inline int append(char* buf, size_t size, int pos, const char* fmt, ...) {
+    if ((size_t)pos >= size) return -1;
 
-    cJSON* payload_obj = nullptr;
-    if (msg->payload) {
-        payload_obj = cJSON_Duplicate(msg->payload, 1); // deep copy
-    } else {
-        payload_obj = cJSON_CreateObject();
+    va_list args;
+    va_start(args, fmt);
+    int written = vsnprintf(buf + pos, size - pos, fmt, args);
+    va_end(args);
+
+    if (written < 0 || (size_t)(pos + written) >= size) {
+        return -1;
     }
-    cJSON_AddItemToObject(root, "payload", payload_obj);
 
-    return root;
+    return pos + written;
 }
 
-ProtocolMessage protocol_message_from_json(const cJSON* root) {
-    ProtocolMessage msg;
+// --- TELEMETRY (single measurement) ---
+int build_telemetry_single(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* metric,
+    double value,
+    const char* unit,
+    const char* source,
+    int64_t m_ts_ms
+) {
+    int pos = 0;
 
-    const cJSON* item = nullptr;
+    // header
+    pos = append(buf, buf_size, pos,
+        "{\"v\":%d,\"id\":\"%s\",\"type\":\"telemetry\",\"ts\":%lld,"
+        "\"deviceId\":\"%s\",\"payload\":{\"measurements\":[",
+        PROTOCOL_VERSION,
+        id,
+        (long long)ts_ms,
+        device_id
+    );
+    if (pos < 0) return -1;
 
-    item = cJSON_GetObjectItem(root, "v");
-    if (item && cJSON_IsNumber(item)) msg.v = item->valueint;
+    // measurement start
+    pos = append(buf, buf_size, pos,
+        "{\"metric\":\"%s\",\"value\":%.3f",
+        metric,
+        value
+    );
+    if (pos < 0) return -1;
 
-    item = cJSON_GetObjectItem(root, "id");
-    if (item && cJSON_IsString(item)) msg.id = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "type");
-    if (item && cJSON_IsString(item)) msg.type = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "ts");
-    if (item && cJSON_IsNumber(item)) msg.ts = item->valuedouble; // uint64_t
-
-    item = cJSON_GetObjectItem(root, "deviceId");
-    if (item && cJSON_IsString(item)) msg.deviceId = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "payload");
-    if (item && cJSON_IsObject(item)) {
-        msg.payload = cJSON_Duplicate(item, 1); // deep copy
-    } else {
-        msg.payload = cJSON_CreateObject();
+    // optional
+    if (unit) {
+        pos = append(buf, buf_size, pos, ",\"unit\":\"%s\"", unit);
+        if (pos < 0) return -1;
     }
 
-    return msg;
+    if (source) {
+        pos = append(buf, buf_size, pos, ",\"source\":\"%s\"", source);
+        if (pos < 0) return -1;
+    }
+
+    if (m_ts_ms > 0) {
+        pos = append(buf, buf_size, pos, ",\"ts\":%lld", (long long)m_ts_ms);
+        if (pos < 0) return -1;
+    }
+
+    // close measurement + payload
+    pos = append(buf, buf_size, pos, "}]}}");
+    if (pos < 0) return -1;
+
+    return pos;
+}
+
+// --- EVENT ---
+int build_event(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* name,
+    const char* severity,
+    const char* message
+) {
+    int pos = 0;
+
+    // header
+    pos = append(buf, buf_size, pos,
+        "{\"v\":%d,\"id\":\"%s\",\"type\":\"event\",\"ts\":%lld,"
+        "\"deviceId\":\"%s\",\"payload\":{",
+        PROTOCOL_VERSION,
+        id,
+        (long long)ts_ms,
+        device_id
+    );
+    if (pos < 0) return -1;
+
+    // required
+    pos = append(buf, buf_size, pos, "\"name\":\"%s\"", name);
+    if (pos < 0) return -1;
+
+    // optional
+    if (severity) {
+        pos = append(buf, buf_size, pos, ",\"severity\":\"%s\"", severity);
+        if (pos < 0) return -1;
+    }
+
+    if (message) {
+        pos = append(buf, buf_size, pos, ",\"message\":\"%s\"", message);
+        if (pos < 0) return -1;
+    }
+
+    // close
+    pos = append(buf, buf_size, pos, "}}");
+    if (pos < 0) return -1;
+
+    return pos;
 }