File content as of revision 0:ab775bf55fe4:

#include "TransferService.h"
#include "Logger.h"
#include "Configuration.h"

namespace Transfer
{

// Transfer base UUID: ADC710C2-xxxx-4BF5-8244-3CEAAA0F87F5
#define transfer_UUID(x)   { 0xAD, 0xC7, 0x10, 0xC2, (((x) & 0xFF00) >> 8), ((x) & 0xFF), 0x4B, 0xF5, 0x82, 0x44, 0x3C, 0xEA, 0xAA, 0x0F, 0x87, 0xF5 }

// UUID byte arrays
static const uint8_t transferServiceUUID[]   = transfer_UUID(0xACDC);
static const uint8_t transferFileInfoUUID[]  = transfer_UUID(0xACDF);
static const uint8_t transferFileBlocksUUID[6][16] =
{
    transfer_UUID(0xACE0), 
    transfer_UUID(0xACE1), 
    transfer_UUID(0xACE2), 
    transfer_UUID(0xACE3), 
    transfer_UUID(0xACE4), 
    transfer_UUID(0xACE5),
};

// UUID objects used to initialise Bluetooth API
static UUID transferServiceUUID_   = UUID(transferServiceUUID);
static UUID transferFileInfoUUID_  = UUID(transferFileInfoUUID);
static UUID transferFileBlocksUUID_[6] =
{
    UUID(transferFileBlocksUUID[0]), 
    UUID(transferFileBlocksUUID[1]), 
    UUID(transferFileBlocksUUID[2]), 
    UUID(transferFileBlocksUUID[3]), 
    UUID(transferFileBlocksUUID[4]), 
    UUID(transferFileBlocksUUID[5]), 
};

// Storage for the value of the characteristics
struct fileInfo_t {
    uint16_t length;
    uint16_t crc16;
};
static struct fileInfo_t            fileInfo;
struct fileBlock_t {
    uint16_t blockNumber;
    uint8_t data[16];
};
static struct fileBlock_t           fileBlocks[6]; // 6 blocks

// Other things needed for operation
static BLEDevice*                   ble;
static Timer                        downloadTimer;

static uint16_t expectingBlock = 0;

static bool acceptFile = true; // additional condition whether to accept a file upload or not, currently always accept
static bool downloadInProgress = false; // indicates if we are downloading a file from the phone

static GattCharacteristic transferFileInfo(transferFileInfoUUID_,
                                        (uint8_t*) &fileInfo,
                                        sizeof(fileInfo),
                                        sizeof(fileInfo),
                                        GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE
                                        | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY);

static uint8_t fileBlockProperties =
        GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE
        | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE;
        
static GattCharacteristic transferFileBlocks[6] = {
        GattCharacteristic(transferFileBlocksUUID_[0], (uint8_t*) &fileBlocks[0], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
        GattCharacteristic(transferFileBlocksUUID_[1], (uint8_t*) &fileBlocks[1], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
        GattCharacteristic(transferFileBlocksUUID_[2], (uint8_t*) &fileBlocks[2], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
        GattCharacteristic(transferFileBlocksUUID_[3], (uint8_t*) &fileBlocks[3], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
        GattCharacteristic(transferFileBlocksUUID_[4], (uint8_t*) &fileBlocks[4], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
        GattCharacteristic(transferFileBlocksUUID_[5], (uint8_t*) &fileBlocks[5], sizeof(fileBlock_t), sizeof(fileBlock_t), fileBlockProperties),
    };
        
static GattCharacteristic* allChars[] = 
{ 
    &transferFileInfo,
    &transferFileBlocks[0], 
    &transferFileBlocks[1], 
    &transferFileBlocks[2], 
    &transferFileBlocks[3], 
    &transferFileBlocks[4], 
    &transferFileBlocks[5],  
};

static GattService transferService(transferServiceUUID_, allChars, sizeof(allChars) / sizeof(GattCharacteristic*));

void init(BLEDevice &bleDevice)
{
    downloadInProgress = false;
    ble = &bleDevice;
    ble->addService(transferService);
    DEBUG("Added transfer service\r\n");
}

void reset()
{
    // reset internal state on new connection
    downloadInProgress = false;
}

const uint8_t* getServiceUUIDp()
{
    return transferServiceUUID;
}

void requestBlock(uint16_t); // prototype declaration
void sendFileInfo();
void refuseFile();
void sendFileDownloadedSuccessfully();

void handleDataWritten(uint16_t handle)
{
    if (!ble)
        return;
        
    int channel = expectingBlock % 6;

    if (handle == transferFileInfo.getHandle()) {

        uint16_t len = sizeof(fileInfo);
        ble->readCharacteristicValue(handle, (uint8_t*) &fileInfo, &len);

        if (fileInfo.length == 0 && fileInfo.crc16 == 0) {
            // signal to cancel pending upload
            downloadInProgress = false;
            downloadTimer.reset();
            expectingBlock = 0;
            DEBUG("Download RESET\r\n");
            return;
        }

        DEBUG("Offered file len=%d, crc=0x%04x, acceptFile=%d, downloadInProgress=%d\r\n", fileInfo.length, fileInfo.crc16, acceptFile, downloadInProgress);

        // Now we must decide whether to accept it or not
        if (acceptFile && !downloadInProgress) {
            downloadTimer.reset();
            downloadTimer.start();
            downloadInProgress = true;
            requestBlock(0);
        } else
            refuseFile();

    } else if (handle == transferFileBlocks[channel].getHandle()) {

        uint16_t len = sizeof(fileBlocks[channel]);
        ble->readCharacteristicValue(handle, (uint8_t*) &fileBlocks[channel], &len);

        //DEBUG("blk %d on ch %d (total %d)", fileBlocks[channel].blockNumber, channel, ++blk)
        //DEBUG(".");
        /*
        uint8_t byte;
        for (int i = 2; i < len; i++) {
            byte = *(((uint8_t*) &fileBlock) + i);
            DEBUG("%c", byte, byte);
        }
        */
        
        if (fileBlocks[channel].blockNumber != expectingBlock) {
            DEBUG("Channel %d ok but expected blk %d, not %d!\r\n", channel, expectingBlock, fileBlocks[channel].blockNumber);
            requestBlock(expectingBlock);
            return;
        } else {
            // DEBUG("."); // one dot = one successfully received packet
        }

        if (fileBlocks[channel].blockNumber > (fileInfo.length / Config::blockSize)) {
            DEBUG("Error: block %d is out of range\r\n", fileBlocks[channel].blockNumber);
            return;
        }

        // "processing" step disabled
        //uint16_t offset = fileBlock.blockNumber * Config::blockSize;
        //memcpy(downloadLocation, fileBlock[0].data, Config::blockSize);

        // request next block if needed
        uint16_t nextBlock = fileBlocks[channel].blockNumber + 1;
        if (nextBlock <= fileInfo.length / Config::blockSize)
            requestBlock(nextBlock);
        else {
            sendFileDownloadedSuccessfully();
        }
    } else {
        DEBUG("Got data on ch %d, but expected on ch %d!\r\n", handle - 1, channel);
    }
}

void requestBlock(uint16_t blockNumber)
{
    // Requesting a block by sending notification is disabled for speed
    //ble->updateCharacteristicValue(transferFileBlocks[0].getHandle(), (uint8_t*) &blockNumber, sizeof(blockNumber), false);
    //DEBUG("BlockReq %d --> PHONE\r\n", blockNumber);
    expectingBlock = blockNumber;
}

void sendFileInfo(uint32_t value)
{
    // refusal is indicated by sending a fileInfo with all zeros
    ble->updateCharacteristicValue(transferFileInfo.getHandle(), (uint8_t*) &value, sizeof(value), false);
}

void refuseFile()
{
    sendFileInfo(0);
}

void sendFileDownloadedSuccessfully()
{
    sendFileInfo(1);
    downloadInProgress = false;
    downloadTimer.stop();
    DEBUG("File transfer took %0.1f sec\r\n", downloadTimer.read());
}

} // namespace transfer