* first draft of new ConfigSerializer. (simple embedded JSON prefs)

src/helpers/ConfigSerializer.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include <Arduino.h>
+
+#ifndef CONFIF_MAX_DEPTH
+  #define CONFIF_MAX_DEPTH   8
+#endif
+
+#ifndef CONFIG_MAX_KEYLEN
+  #define CONFIG_MAX_KEYLEN  16
+#endif
+
+#ifndef CONFIG_MAX_TOKEN_LEN
+  #define CONFIG_MAX_TOKEN_LEN   128
+#endif
+
+class ConfigSerializer {
+  bool _first;
+  int8_t _depth;
+
+  enum OP { READ, WRITE };
+
+  class Context {
+    Stream* _f;
+    OP _op;
+    uint8_t rd_len;
+    uint8_t rd_mode;
+    char pending;
+    char rd_buf[CONFIG_MAX_TOKEN_LEN];
+    char _keys[CONFIF_MAX_DEPTH][CONFIG_MAX_KEYLEN];
+
+  public:
+    bool success = true;
+    Context(Stream* f, OP op) : _f(f), _op(op) { rd_buf[rd_len = 0] = 0; rd_mode = 0; pending = 0; }
+    OP op() const { return _op; }
+    Stream* file() const { return _f; }
+    int readNext();
+    const char* getToken() const { return rd_buf; }
+    bool keyMatch(int8_t depth, const char* key) { return strcmp(key, _keys[depth]) == 0; }
+    void setKey(uint8_t depth, const char* key) { strcpy(_keys[depth], key);  }
+  };
+
+  Context* _context = NULL;
+
+  void writeComma();
+
+protected:
+  ConfigSerializer() { }
+
+  void def(const char* key, char* value, size_t max_len);  // max_len inclusive of null
+  void def(const char* key, int32_t& value);
+  void def(const char* key, int16_t& value);
+  void def(const char* key, int8_t& value);
+  void def(const char* key, uint32_t& value);
+  void def(const char* key, uint16_t& value);
+  void def(const char* key, uint8_t& value);
+  void def(const char* key, float& value);
+  void def(const char* key, double& value);
+  void def(const char* key, bool& value);
+  void def(const char* key, ConfigSerializer& sub_obj);
+
+  virtual void structure() = 0;
+
+public:
+  bool loadSerial(Stream& s);
+  bool saveSerial(Stream& s);
+};