/**************************************************************************/
/*!
    @file     BLECharacteristic.cpp
    @author   hathach (tinyusb.org)

    @section LICENSE

    Software License Agreement (BSD License)

    Copyright (c) 2018, Adafruit Industries (adafruit.com)
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:
    1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.
    3. Neither the name of the copyright holders nor the
    names of its contributors may be used to endorse or promote products
    derived from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
    EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
    DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
    ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**************************************************************************/

#include "bluefruit.h"

void BLECharacteristic::_init(void)
{
  _is_temp = false;
  _max_len = BLE_GATT_ATT_MTU_DEFAULT-3;
  _service = NULL;

  _usr_descriptor = NULL;
  varclr(&_report_ref_desc);
  varclr(&_format_desc);

  varclr(&_properties);

  varclr(&_attr_meta);
  _attr_meta.read_perm = _attr_meta.write_perm = BLE_SECMODE_OPEN;
  _attr_meta.vlen = 1;
  _attr_meta.vloc = BLE_GATTS_VLOC_STACK;

  _handles.value_handle     = BLE_GATT_HANDLE_INVALID;
  _handles.user_desc_handle = BLE_GATT_HANDLE_INVALID;
  _handles.sccd_handle      = BLE_GATT_HANDLE_INVALID;
  _handles.cccd_handle      = BLE_GATT_HANDLE_INVALID;

  _long_wr.buffer = NULL;
  _long_wr.bufsize = 0;
  _long_wr.count = 0;

  _rd_authorize_cb = NULL;
  _wr_authorize_cb = NULL;
  _wr_cb           = NULL;
  _cccd_wr_cb      = NULL;
}

BLECharacteristic::BLECharacteristic(void)
  : uuid()
{
  _init();
}

BLECharacteristic::BLECharacteristic(BLEUuid bleuuid)
  : uuid(bleuuid)
{
  _init();
}

void BLECharacteristic::setUuid(BLEUuid bleuuid)
{
  uuid = bleuuid;
}

BLEService& BLECharacteristic::parentService (void)
{
  return *_service;
}

/**
 * Destructor
 */
BLECharacteristic::~BLECharacteristic()
{
//   Bluefruit.Gatt._removeCharacteristic(this);
}

/**
 * Must be set when Charactertistic is declared locally (e.g insdie function)
 * and is not last throughout programs. Useful for one-shot set-and-forget
 * Characteristics such as read-only one. Where there is no need for interactions
 * later on. This call will prevent the Characteristics to be hooked into
 * managing chars list of AdafruitBluefruit
 */
void BLECharacteristic::setTempMemory(void)
{
  _is_temp = true;
}

void BLECharacteristic::setProperties(uint8_t prop)
{
  memcpy(&_properties, &prop, 1);
}

void BLECharacteristic::setMaxLen(uint16_t max_len)
{
  _max_len = max_len;
}

void BLECharacteristic::setFixedLen(uint16_t fixed_len)
{
  if ( fixed_len )
  {
    _max_len = fixed_len;
    _attr_meta.vlen = 0;
  }else
  {
    _attr_meta.vlen = 1;
  }
}

void BLECharacteristic::setPermission(BleSecurityMode read_perm, BleSecurityMode write_perm)
{
  memcpy(&_attr_meta.read_perm , &read_perm, 1);
  memcpy(&_attr_meta.write_perm, &write_perm, 1);
}

void BLECharacteristic::setWriteCallback(write_cb_t fp)
{
  _wr_cb = fp;
}

void BLECharacteristic::setCccdWriteCallback(write_cccd_cb_t fp)
{
  _cccd_wr_cb = fp;
}

void BLECharacteristic::setReadAuthorizeCallback(read_authorize_cb_t fp)
{
  _attr_meta.rd_auth = (fp  ? 1 : 0);
  _rd_authorize_cb = fp;
}

void BLECharacteristic::setWriteAuthorizeCallback(write_authorize_cb_t fp)
{
  _attr_meta.wr_auth = (fp ? 1 : 0);
  _wr_authorize_cb = fp;
}

void BLECharacteristic::setUserDescriptor(const char* descriptor)
{
  _usr_descriptor = descriptor;
}

void BLECharacteristic::setReportRefDescriptor(uint8_t id, uint8_t type)
{
  _report_ref_desc.id   = id;
  _report_ref_desc.type = type;
}

/**
 * https://developer.bluetooth.org/gatt/descriptors/Pages/DescriptorViewer.aspx?u=org.bluetooth.descriptor.gatt.characteristic_presentation_format.xml
 * @param type      BLE_GATT_CPF_FORMAT_x value, see ble_gatt.h
 * @param exponent  exponent
 * @param unit      UUID16_UNIT_x, see BLEUuid.h
 */
void BLECharacteristic::setPresentationFormatDescriptor(uint8_t type, int8_t exponent, uint16_t unit, uint8_t name_space, uint16_t descritpor)
{
  _format_desc.format     = type;
  _format_desc.exponent   = exponent;
  _format_desc.unit       = unit;
  _format_desc.name_space = name_space;
  _format_desc.desc       = descritpor;
}

ble_gatts_char_handles_t BLECharacteristic::handles(void)
{
  return _handles;
}

err_t BLECharacteristic::begin(void)
{
  _service = BLEService::lastService;

  // Add UUID128 if needed
  (void) uuid.begin();

  // Permission is OPEN if passkey is disabled.
//  if (!nvm_data.core.passkey_enable) BLE_GAP_CONN_SEC_MODE_SET_OPEN(&p_char_def->permission);

  // Correct Read/Write permission according to properties
  if ( !(_properties.read || _properties.notify || _properties.indicate ) )
  {
    _attr_meta.read_perm = BLE_SECMODE_NO_ACCESS;
  }

  if ( !(_properties.write || _properties.write_wo_resp ) )
  {
    _attr_meta.write_perm = BLE_SECMODE_NO_ACCESS;
  }

  /* CCCD attribute metadata */
  ble_gatts_attr_md_t cccd_md;

  if ( _properties.notify || _properties.indicate )
  {
    /* Notification & Indication require CCCD */
    memclr( &cccd_md, sizeof(ble_gatts_attr_md_t) );
    cccd_md.vloc = BLE_GATTS_VLOC_STACK;

    cccd_md.read_perm  = BLE_SECMODE_OPEN;
    cccd_md.write_perm = _attr_meta.read_perm;
  }

  /* Characteristic metadata */
  ble_gatts_char_md_t char_md;
  varclr(&char_md);

  char_md.char_props = _properties;
  char_md.p_cccd_md  = (_properties.notify || _properties.indicate) ? &cccd_md : NULL;

  /* Characteristic extended properties (for user description) */
  ble_gatts_attr_md_t desc_md =
  {
      .read_perm  = _attr_meta.read_perm,
      .write_perm = BLE_SECMODE_NO_ACCESS,
      .vlen       = 0,
      .vloc       = BLE_GATTS_VLOC_STACK,
  };

  if (_usr_descriptor != NULL && _usr_descriptor[0] != 0)
  {
    char_md.p_char_user_desc    = (uint8_t*) _usr_descriptor;
    char_md.char_user_desc_size = char_md.char_user_desc_max_size = strlen(_usr_descriptor);
    char_md.p_user_desc_md      = &desc_md;
    //char_md.char_ext_props    = ext_props,
  }

  /* Presentation Format Descriptor */
  if ( _format_desc.format != 0 )
  {
    char_md.p_char_pf = &_format_desc;
  }

  /* GATT attribute declaration */
  ble_gatts_attr_t attr_char_value =
  {
    .p_uuid    = &uuid._uuid,
    .p_attr_md = &_attr_meta,
    .init_len  = (_attr_meta.vlen == 1) ? (uint16_t) 0 : _max_len,
    .init_offs = 0,
    .max_len   = _max_len,
    .p_value   = NULL
  };

  VERIFY_STATUS( sd_ble_gatts_characteristic_add(BLE_GATT_HANDLE_INVALID, &char_md, &attr_char_value, &_handles) );

  // Report Reference Descriptor if any (required by HID)
  if ( _report_ref_desc.type )
  {
    // Reference Descriptor
    ble_gatts_attr_md_t ref_md =
    {
        .read_perm  = _attr_meta.read_perm,
        .write_perm = BLE_SECMODE_NO_ACCESS,
        .vlen       = 0,
        .vloc       = BLE_GATTS_VLOC_STACK
    };

    ble_uuid_t ref_uuid = { .uuid = UUID16_REPORT_REF_DESCR, .type = BLE_UUID_TYPE_BLE };
    ble_gatts_attr_t ref_desc =
    {
        .p_uuid    = &ref_uuid,
        .p_attr_md = &ref_md,
        .init_len  = sizeof(_report_ref_desc),
        .init_offs = 0,
        .max_len   = sizeof(_report_ref_desc),
        .p_value   = (uint8_t*) &_report_ref_desc
    };

    uint16_t ref_hdl;
    VERIFY_STATUS ( sd_ble_gatts_descriptor_add(BLE_GATT_HANDLE_INVALID, &ref_desc, &ref_hdl) );

    (void) ref_hdl; // not used
  }

  // Currently Only register to Bluefruit if The Characteristic is not temporary memory i.e local variable
  if ( !_is_temp )
  {
    (void) Bluefruit.Gatt._addCharacteristic(this);
  }

  return ERROR_NONE;
}

err_t BLECharacteristic::addDescriptor(BLEUuid bleuuid, void const * content, uint16_t len, BleSecurityMode read_perm, BleSecurityMode write_perm)
{
  // Meta Data
  ble_gatts_attr_md_t meta;
  varclr(&meta);

  memcpy(&meta.read_perm , &read_perm , 1);
  memcpy(&meta.write_perm, &write_perm, 1);
  meta.vlen = 0;
  meta.vloc = BLE_GATTS_VLOC_STACK;

  // Descriptor
  (void) bleuuid.begin();

  ble_gatts_attr_t desc =
  {
      .p_uuid    = &bleuuid._uuid,
      .p_attr_md = &meta,
      .init_len  = len,
      .init_offs = 0,
      .max_len   = len,
      .p_value   = (uint8_t*) content
  };

  uint16_t hdl;
  VERIFY_STATUS ( sd_ble_gatts_descriptor_add(BLE_GATT_HANDLE_INVALID, &desc, &hdl) );

  return ERROR_NONE;
}

/**
 * @param event
 */
void BLECharacteristic::_eventHandler(ble_evt_t* event)
{
  uint16_t const conn_hdl = event->evt.common_evt.conn_handle;

  switch(event->header.evt_id)
  {
    case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
    {
      ble_gatts_evt_rw_authorize_request_t * request = &event->evt.gatts_evt.params.authorize_request;

      if (request->type == BLE_GATTS_AUTHORIZE_TYPE_WRITE)
      {
        ble_gatts_evt_write_t * wr_req = &request->request.write;

        switch(wr_req->op)
        {
          case BLE_GATTS_OP_PREP_WRITE_REQ:
          {
            // Prepare Long Write
            if ( !_long_wr.buffer )
            {
              // Allocate long write buffer if not previously
              _long_wr.bufsize = 1024; // TODO bufsize is 10x MTU
              _long_wr.buffer = (uint8_t*) rtos_malloc(_long_wr.bufsize);
              _long_wr.count = 0;
            }

            ble_gatts_rw_authorize_reply_params_t reply = { .type = BLE_GATTS_AUTHORIZE_TYPE_WRITE };

            if ( wr_req->offset + wr_req->len > _long_wr.bufsize )
            {
              reply.params.write.gatt_status = BLE_GATT_STATUS_ATTERR_PREPARE_QUEUE_FULL;
            }else
            {
              reply.params.write = ((ble_gatts_authorize_params_t) {
                  .gatt_status = BLE_GATT_STATUS_SUCCESS,
                  .update      = 1,
                  .offset      = wr_req->offset,
                  .len         = wr_req->len,
                  .p_data      = wr_req->data
              });

              memcpy(_long_wr.buffer+wr_req->offset, wr_req->data, wr_req->len);
              _long_wr.count = max16(_long_wr.count, wr_req->offset + wr_req->len);
            }

            sd_ble_gatts_rw_authorize_reply(conn_hdl, &reply);
          }
          break;

          case BLE_GATTS_OP_EXEC_WRITE_REQ_NOW:
            // Execute Long Write
            if ( _long_wr.buffer )
            {
              ble_gatts_rw_authorize_reply_params_t reply = { .type = BLE_GATTS_AUTHORIZE_TYPE_WRITE };
              reply.params.write.gatt_status = BLE_GATT_STATUS_SUCCESS;

              sd_ble_gatts_rw_authorize_reply(conn_hdl, &reply);

              // Long write complete, call write callback if set
              if (_wr_cb) _wr_cb(*this, _long_wr.buffer, _long_wr.count, 0);

              // free up memory
              rtos_free(_long_wr.buffer);
              _long_wr.buffer = NULL;
              _long_wr.bufsize = _long_wr.count = 0;
            }
          break;

          case BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL:
            // Cancel Long Write
          break;

          case BLE_GATTS_OP_WRITE_REQ:
            // Write Request with authorization
            if (_wr_authorize_cb != NULL) _wr_authorize_cb(*this, &request->request.write);
          break;

          default: break;
        }
      }

      if ( (request->type == BLE_GATTS_AUTHORIZE_TYPE_READ) && (_rd_authorize_cb != NULL))
      {
        _rd_authorize_cb(*this, &request->request.read);
      }
    }
    break;

    case BLE_GATTS_EVT_WRITE:
    {
      ble_gatts_evt_write_t* request = &event->evt.gatts_evt.params.write;

      LOG_LV2_BUFFER(NULL, request->data, request->len);

      // Value write
      if (request->handle == _handles.value_handle)
      {
        LOG_LV2("GATTS", "attr's value, uuid = 0x%04X", request->uuid.uuid);
        // TODO Ada callback
        if (_wr_cb)
        {
//          uint8_t* data = (uint8_t*) rtos_malloc(request->len);
//
//          if (data)
//          {
//            ada_callback(data, _wr_cb, *this, data, request->len, request->offset);
//          }else
          {
            // invoke directly if cannot allocate memory for data
            _wr_cb(*this, request->data, request->len, request->offset);
          }
        }
      }

      // CCCD write
      if ( request->handle == _handles.cccd_handle )
      {
        LOG_LV2("GATTS", "attr's cccd");

        // Invoke callback if set
        if (_cccd_wr_cb)
        {
          uint16_t value;
          memcpy(&value, request->data, 2);
          _cccd_wr_cb(*this, value);
        }
      }
    }
    break;

    default: break;
  }
}

/*------------------------------------------------------------------*/
/* WRITE
 *------------------------------------------------------------------*/
uint16_t BLECharacteristic::write(const char   * str)
{
  return write((const uint8_t*) str, strlen(str));
}

uint16_t BLECharacteristic::write(const void* data, uint16_t len)
{
  ble_gatts_value_t value =
  {
      .len     = min16(len, _max_len), // could not exceed max len
      .offset  = 0                   , // TODO gatts long write
      .p_value = (uint8_t*) data
  };

  // conn handle only needed for system attribute
  VERIFY_STATUS( sd_ble_gatts_value_set(BLE_CONN_HANDLE_INVALID, _handles.value_handle, &value), 0 );

  return value.len;
}

uint16_t BLECharacteristic::write8(uint8_t num)
{
  return write( (uint8_t*) &num, sizeof(num));
}

uint16_t BLECharacteristic::write16(uint16_t num)
{
  return write( (uint8_t*) &num, sizeof(num));
}

uint16_t BLECharacteristic::write32(uint32_t num)
{
  return write( (uint8_t*) &num, sizeof(num));
}

uint16_t BLECharacteristic::write32(int num)
{
  return write32( (uint32_t) num );
}

/*------------------------------------------------------------------*/
/* READ
 *------------------------------------------------------------------*/
/**
 * Read Characteristic's value
 * @param buffer  memory to hold value
 * @param len     size of memory
 * @param offset  offset of value (dfeault is 0)
 * @return  number of read bytes
 */
uint16_t BLECharacteristic::read(void* buffer, uint16_t bufsize, uint16_t offset)
{
  ble_gatts_value_t value =
  {
      .len     = bufsize,
      .offset  = offset,
      .p_value = (uint8_t*) buffer
  };

  // conn handle only needed for system attribute
  VERIFY_STATUS(sd_ble_gatts_value_get(BLE_CONN_HANDLE_INVALID, _handles.value_handle, &value), 0);

  return value.len;
}

uint8_t BLECharacteristic::read8(void)
{
  uint8_t num;
  return read(&num, sizeof(num)) ? num : 0;
}

uint16_t BLECharacteristic::read16(void)
{
  uint16_t num;
  return read(&num, sizeof(num)) ? num : 0;
}

uint32_t BLECharacteristic::read32(void)
{
  uint32_t num;
  return read(&num, sizeof(num)) ? num : 0;
}


uint16_t BLECharacteristic::getCccd(void)
{
  VERIFY( Bluefruit.connected() && (_handles.cccd_handle != BLE_GATT_HANDLE_INVALID), 0 );

  uint16_t cccd;
  ble_gatts_value_t value =
  {
      .len     = 2,
      .offset  = 0,
      .p_value = (uint8_t*) &cccd
  };

  err_t err = sd_ble_gatts_value_get(Bluefruit.connHandle(), _handles.cccd_handle, &value);

  // CCCD is not set, count as not enabled
  if ( BLE_ERROR_GATTS_SYS_ATTR_MISSING == err )
  {
    cccd = 0;
  }else
  {
    VERIFY_STATUS(err);
  }

  return cccd;
}

/*------------------------------------------------------------------*/
/* NOTIFY
 *------------------------------------------------------------------*/
bool BLECharacteristic::notifyEnabled(void)
{
  VERIFY( _properties.notify );
  return  (getCccd() & BLE_GATT_HVX_NOTIFICATION);
}

bool BLECharacteristic::notify(const void* data, uint16_t len)
{
  VERIFY( _properties.notify );

  // could not exceed max len
  uint16_t remaining = min16(len, _max_len);

  if ( notifyEnabled() )
  {
    uint16_t const max_payload = Bluefruit.Gap.getMTU( Bluefruit.connHandle() ) - 3;
    const uint8_t* u8data = (const uint8_t*) data;

    while ( remaining )
    {
      // TODO multiple connection support
      // Failed if there is no free buffer
      if ( !Bluefruit.Gap.getHvnPacket( Bluefruit.connHandle() ) )  return false;

      uint16_t packet_len = min16(max_payload, remaining);

      ble_gatts_hvx_params_t hvx_params =
      {
          .handle = _handles.value_handle,
          .type   = BLE_GATT_HVX_NOTIFICATION,
          .offset = 0,
          .p_len  = &packet_len,
          .p_data = (uint8_t*) u8data,
      };

      LOG_LV2("CHR", "Notify %d bytes", packet_len);
      VERIFY_STATUS( sd_ble_gatts_hvx(Bluefruit.connHandle(), &hvx_params), false );

      remaining -= packet_len;
      u8data    += packet_len;
    }
  }
  else
  {
    write(data, remaining);
    return false;
  }

  return true;
}

bool BLECharacteristic::notify(const char * str)
{
  return notify( (const uint8_t*) str, strlen(str) );
}

bool BLECharacteristic::notify8(uint8_t num)
{
  return notify( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::notify16(uint16_t num)
{
  return notify( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::notify32(uint32_t num)
{
  return notify( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::notify32(int num)
{
  return notify32( (uint32_t) num);
}

/*------------------------------------------------------------------*/
/* INDICATE
 *------------------------------------------------------------------*/
bool BLECharacteristic::indicateEnabled(void)
{
  VERIFY( _properties.indicate );
  return  (getCccd() & BLE_GATT_HVX_INDICATION);
}

bool BLECharacteristic::indicate(const void* data, uint16_t len)
{
  VERIFY( _properties.indicate );

  // could not exceed max len
  uint16_t remaining = min16(len, _max_len);

  if ( indicateEnabled() )
  {
    uint16_t conn_hdl = Bluefruit.connHandle();

    uint16_t const max_payload = Bluefruit.Gap.getMTU( conn_hdl ) - 3;
    const uint8_t* u8data = (const uint8_t*) data;

    while ( remaining )
    {
      uint16_t packet_len = min16(max_payload, remaining);

      ble_gatts_hvx_params_t hvx_params =
      {
          .handle = _handles.value_handle,
          .type   = BLE_GATT_HVX_INDICATION,
          .offset = 0,
          .p_len  = &packet_len,
          .p_data = (uint8_t*) u8data,
      };

      LOG_LV2("CHR", "Indicate %d bytes", packet_len);

      // Blocking wait until receiving confirmation from peer
      VERIFY_STATUS( sd_ble_gatts_hvx( conn_hdl, &hvx_params), false );
      VERIFY ( Bluefruit.Gatt.waitForIndicateConfirm(conn_hdl) );

      remaining -= packet_len;
      u8data    += packet_len;
    }
  }
  else
  {
    write(data, remaining);
    return false;
  }

  return true;
}

bool BLECharacteristic::indicate(const char * str)
{
  return indicate( (const uint8_t*) str, strlen(str) );
}

bool BLECharacteristic::indicate8(uint8_t num)
{
  return indicate( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::indicate16(uint16_t num)
{
  return indicate( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::indicate32(uint32_t num)
{
  return indicate( (uint8_t*) &num, sizeof(num));
}

bool BLECharacteristic::indicate32(int num)
{
  return indicate32( (uint32_t) num);
}