#include <Arduino.h>
#include "configuration.h"
#include "mesh-pb-constants.h"
#include <pb_encode.h>
#include <pb_decode.h>
#include <assert.h>
#include "FS.h"

/// helper function for encoding a record as a protobuf, any failures to encode are fatal and we will panic
/// returns the encoded packet size
size_t pb_encode_to_bytes(uint8_t *destbuf, size_t destbufsize, const pb_msgdesc_t *fields, const void *src_struct)
{

    pb_ostream_t stream = pb_ostream_from_buffer(destbuf, destbufsize);
    if (!pb_encode(&stream, fields, src_struct))
    {
        DEBUG_MSG("Error: can't encode protobuf %s\n", PB_GET_ERROR(&stream));
        assert(0); // FIXME - panic
    }
    else
    {
        return stream.bytes_written;
    }
}


/// helper function for decoding a record as a protobuf, we will return false if the decoding failed
bool pb_decode_from_bytes(const uint8_t *srcbuf, size_t srcbufsize, const pb_msgdesc_t *fields, void *dest_struct)
{
    pb_istream_t stream = pb_istream_from_buffer(srcbuf, srcbufsize);
    if (!pb_decode(&stream, fields, dest_struct))
    {
        DEBUG_MSG("Error: can't decode protobuf %s\n", PB_GET_ERROR(&stream));
        return false;
    }
    else
    {
        return true;
    }
}


/// Read from an Arduino File
bool readcb(pb_istream_t *stream, uint8_t *buf, size_t count)
{
    File *file = (File *)stream->state;
    bool status;

    if (buf == NULL)
    {
        while (count-- && file->read() != EOF)
            ;
        return count == 0;
    }

    status = (file->read(buf, count) == count);

    if (file->available() == 0)
        stream->bytes_left = 0;

    return status;
}


/// Write to an arduino file
bool writecb(pb_ostream_t *stream, const uint8_t *buf, size_t count)
{
   File *file = (File*) stream->state;
   //DEBUG_MSG("writing %d bytes to protobuf file\n", count);
   return file->write(buf, count) == count;
}