Serializer.h

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// The streaming XML serializer.
//
// The document is a sequence of PARTS, each generated deterministically from the store:
//   0            prologue: <phyphox>, title, category, description, data-containers, the
//                bluetooth input (data channels, phone sensors), the bluetooth output (one
//                <input> per input channel / sensor characteristic), the analysis block with
//                the change detector of every input channel
//   1 … V        one part per view (its opening tag, its elements, its closing tag)
//   V+1          epilogue: the error view if any, the export block, </phyphox>
//
// build() runs every part once through a CountingSink, recording each part's length; the
// cumulative offsets form the PART TABLE. After that, any byte range of the document is served
// by regenerating only the one or two parts it touches through a WindowSink. There is one full
// pass per addExperiment(), never one per packet.
//
// Determinism is the invariant everything rests on: the same store must yield identical bytes
// every time. The host tests assert it (part-table offsets ≡ a full serialization; every
// window ≡ the slice of the full document).
#ifndef PHYPHOX_BLE_CORE_SERIALIZER_H
#define PHYPHOX_BLE_CORE_SERIALIZER_H
 
#include "ExperimentStore.h"
#include "Sink.h"
 
namespace phyphox {
 
class Serializer {
public:
    void build(const ExperimentStore& store, const char* deviceName, uint16_t mtu);
 
    uint32_t size() const { return totalSize_; }   
    uint32_t crc() const { return crc_; }          
    uint16_t partCount() const { return partCount_; }
 
    uint32_t read(uint32_t offset, uint8_t* out, uint32_t n) const;
    void writeAll(Sink& sink) const;
 
    void emitPart(uint16_t part, Sink& sink) const;
 
private:
    const ExperimentStore* store_ = nullptr;
    const char* deviceName_ = nullptr;
    uint16_t mtu_ = PHYPHOX_BLE_DEFAULT_MTU;
    uint32_t totalSize_ = 0;
    uint32_t crc_ = 0;
    uint16_t partCount_ = 0;
    uint16_t* partOffset_ = nullptr;
 
    void emitPrologue(Sink&) const;
    void emitView(uint8_t view, Sink&) const;
    void emitElement(const ElementData&, Sink&) const;
    void emitEpilogue(Sink&) const;
};
 
void writeEscaped(Sink&, const char* text);
void writeFloat(Sink&, float v);
void writeInt(Sink&, int32_t v);
void writeInputCharUuid(Sink&, uint8_t channel);
void writeSensorCharUuid(Sink&, uint8_t sensor);
 
} // namespace phyphox
 
#endif