TemplateStream.h

/****
 * Sming Framework Project - Open Source framework for high efficiency native ESP8266 development.
 * Created 2015 by Skurydin Alexey
 * http://github.com/anakod/Sming
 * All files of the Sming Core are provided under the LGPL v3 license.
 *
 * TemplateStream.h
 *
 ****/

#ifndef _SMING_CORE_DATA_STREAM_TEMPLATE_STREAM_H_
#define _SMING_CORE_DATA_STREAM_TEMPLATE_STREAM_H_

#include "DataSourceStream.h"
#include "WHashMap.h"
#include "WString.h"

#define TEMPLATE_MAX_VAR_NAME_LEN 16

class TemplateVariables : public HashMap<String, String>
{
};

enum TemplateExpandState {
    eTES_Wait,      
    eTES_Found,     
    eTES_StartVar,  
    eTES_SendingVar 
};
class TemplateStream : public IDataSourceStream
{
public:
    TemplateStream(IDataSourceStream* stream) : stream(stream)
    {
        // Pre-allocate string to maximum length
        varName.reserve(TEMPLATE_MAX_VAR_NAME_LEN);
    }

    ~TemplateStream()
    {
        delete stream;
    }

    //Use base class documentation
    StreamType getStreamType() const override
    {
        return stream ? eSST_Template : eSST_Invalid;
    }

    //Use base class documentation
    uint16_t readMemoryBlock(char* data, int bufSize) override;

    //Use base class documentation
    bool seek(int len) override;

    bool isFinished() override
    {
        return stream ? stream->isFinished() : true;
    }

    void setVar(const String& name, const String& value)
    {
        templateData[name] = value;
    }

    void setVars(const TemplateVariables& vars)
    {
        templateData.setMultiple(vars);
    }

    inline TemplateVariables& variables()
    {
        return templateData;
    }

    String getName() const override
    {
        return stream ? stream->getName() : nullptr;
    }

private:
    IDataSourceStream* stream = nullptr;
    TemplateVariables templateData;
    TemplateExpandState state = eTES_Wait;
    String varName;
    size_t skipBlockSize = 0;
    size_t varDataPos = 0;
    size_t varWaitSize = 0;
};

#endif /* _SMING_CORE_DATA_STREAM_TEMPLATE_STREAM_H_ */