text: /*
   * Copyright (C) 2017 BlueKitchen GmbH
   *
   * 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
   *    contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   * 4. Any redistribution, use, or modification is done solely for
   *    personal benefit and not for any commercial purpose or for
   *    monetary gain.
   *
   * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
   * ``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 MATTHIAS
   * RINGWALD OR CONTRIBUTORS 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.
   *
   * Please inquire about commercial licensing options at 
   * contact@bluekitchen-gmbh.com
   *
   */
  
  #define BTSTACK_FILE__ "hid_host_demo.c"
  
  /*
   * hid_host_demo.c
   */
  
  /* EXAMPLE_START(hid_host_demo): HID Host Classic
   *
   * @text This example implements a HID Host. For now, it connects to a fixed device.
   * It will connect in Report protocol mode if this mode is supported by the HID Device,
   * otherwise it will fall back to BOOT protocol mode. 
   */
  
  #include <inttypes.h>
  #include <stdio.h>
  
  #include "btstack_config.h"
  #include "btstack.h"
  
  #define MAX_ATTRIBUTE_VALUE_SIZE 300
  
  // MBP 2016 static const char * remote_addr_string = "F4-0F-24-3B-1B-E1";
  // iMpulse static const char * remote_addr_string = "64:6E:6C:C1:AA:B5";
  // Logitec 
  static const char * remote_addr_string = "00:1F:20:86:DF:52";
  
  static bd_addr_t remote_addr;
  
  static btstack_packet_callback_registration_t hci_event_callback_registration;
  
  // Simplified US Keyboard with Shift modifier
  
  #define CHAR_ILLEGAL     0xff
  #define CHAR_RETURN     '\n'
  #define CHAR_ESCAPE      27
  #define CHAR_TAB         '\t'
  #define CHAR_BACKSPACE   0x7f
  
  /**
   * English (US)
   */
  static const uint8_t keytable_us_none [] = {
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /*   0-3 */
      'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',                   /*  4-13 */
      'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',                   /* 14-23 */
      'u', 'v', 'w', 'x', 'y', 'z',                                       /* 24-29 */
      '1', '2', '3', '4', '5', '6', '7', '8', '9', '0',                   /* 30-39 */
      CHAR_RETURN, CHAR_ESCAPE, CHAR_BACKSPACE, CHAR_TAB, ' ',            /* 40-44 */
      '-', '=', '[', ']', '\\', CHAR_ILLEGAL, ';', '\'', 0x60, ',',       /* 45-54 */
      '.', '/', CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,   /* 55-60 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 61-64 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 65-68 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 69-72 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 73-76 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 77-80 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 81-84 */
      '*', '-', '+', '\n', '1', '2', '3', '4', '5',                       /* 85-97 */
      '6', '7', '8', '9', '0', '.', 0xa7,                                 /* 97-100 */
  }; 
  
  static const uint8_t keytable_us_shift[] = {
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /*  0-3  */
      'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',                   /*  4-13 */
      'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',                   /* 14-23 */
      'U', 'V', 'W', 'X', 'Y', 'Z',                                       /* 24-29 */
      '!', '@', '#', '$', '%', '^', '&', '*', '(', ')',                   /* 30-39 */
      CHAR_RETURN, CHAR_ESCAPE, CHAR_BACKSPACE, CHAR_TAB, ' ',            /* 40-44 */
      '_', '+', '{', '}', '|', CHAR_ILLEGAL, ':', '"', 0x7E, '<',         /* 45-54 */
      '>', '?', CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,   /* 55-60 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 61-64 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 65-68 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 69-72 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 73-76 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 77-80 */
      CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL, CHAR_ILLEGAL,             /* 81-84 */
      '*', '-', '+', '\n', '1', '2', '3', '4', '5',                       /* 85-97 */
      '6', '7', '8', '9', '0', '.', 0xb1,                                 /* 97-100 */
  }; 
  
  // SDP
  static uint8_t hid_descriptor_storage[MAX_ATTRIBUTE_VALUE_SIZE];
  
  // App
  static enum {
      APP_IDLE,
      APP_CONNECTED
  } app_state = APP_IDLE;
  
  static uint16_t hid_host_cid = 0;
  static bool     hid_host_descriptor_available = false;
  static hid_protocol_mode_t hid_host_report_mode = HID_PROTOCOL_MODE_REPORT_WITH_FALLBACK_TO_BOOT;
  
  /* @section Main application configuration
   *
   * @text In the application configuration, L2CAP and HID host are initialized, and the link policies 
   * are set to allow sniff mode and role change. 
   */
  
  /* LISTING_START(PanuSetup): Panu setup */
  static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
  
  static void hid_host_setup(void){
  
      // Initialize L2CAP 
      l2cap_init();
  
      // Initialize HID Host    
      hid_host_init(hid_descriptor_storage, sizeof(hid_descriptor_storage));
      hid_host_register_packet_handler(packet_handler);
  
      // Allow sniff mode requests by HID device and support role switch
      gap_set_default_link_policy_settings(LM_LINK_POLICY_ENABLE_SNIFF_MODE | LM_LINK_POLICY_ENABLE_ROLE_SWITCH);
  
      // try to become master on incoming connections
      hci_set_master_slave_policy(HCI_ROLE_MASTER);
  
      // register for HCI events
      hci_event_callback_registration.callback = &packet_handler;
      hci_add_event_handler(&hci_event_callback_registration);
  
      // Disable stdout buffering
      setbuf(stdout, NULL);
  }
  /* LISTING_END */
  
  /*
   * @section HID Report Handler
   * 
   * @text Use BTstack's compact HID Parser to process incoming HID Report in Report protocol mode. 
   * Iterate over all fields and process fields with usage page = 0x07 / Keyboard
   * Check if SHIFT is down and process first character (don't handle multiple key presses)
   * 
   */
  
  #define NUM_KEYS 6
  static uint8_t last_keys[NUM_KEYS];
  static void hid_host_handle_interrupt_report(const uint8_t * report, uint16_t report_len){
      // check if HID Input Report
      if (report_len < 1) return;
      if (*report != 0xa1) return; 
      
      report++;
      report_len--;
      
      btstack_hid_parser_t parser;
      btstack_hid_parser_init(&parser, 
          hid_descriptor_storage_get_descriptor_data(hid_host_cid), 
          hid_descriptor_storage_get_descriptor_len(hid_host_cid), 
          HID_REPORT_TYPE_INPUT, report, report_len);
  
      int shift = 0;
      uint8_t new_keys[NUM_KEYS];
      memset(new_keys, 0, sizeof(new_keys));
      int     new_keys_count = 0;
      while (btstack_hid_parser_has_more(&parser)){
          uint16_t usage_page;
          uint16_t usage;
          int32_t  value;
          btstack_hid_parser_get_field(&parser, &usage_page, &usage, &value);
          if (usage_page != 0x07) continue;   
          switch (usage){
              case 0xe1:
              case 0xe6:
                  if (value){
                      shift = 1;
                  }
                  continue;
              case 0x00:
                  continue;
              default:
                  break;
          }
          if (usage >= sizeof(keytable_us_none)) continue;
  
          // store new keys
          new_keys[new_keys_count++] = usage;
  
          // check if usage was used last time (and ignore in that case)
          int i;
          for (i=0;i<NUM_KEYS;i++){
              if (usage == last_keys[i]){
                  usage = 0;
              }
          }
          if (usage == 0) continue;
  
          uint8_t key;
          if (shift){
              key = keytable_us_shift[usage];
          } else {
              key = keytable_us_none[usage];
          }
          if (key == CHAR_ILLEGAL) continue;
          if (key == CHAR_BACKSPACE){ 
              printf("\b \b");    // go back one char, print space, go back one char again
              continue;
          }
          printf("%c", key);
      }
      memcpy(last_keys, new_keys, NUM_KEYS);
  }
  
  /*
   * @section Packet Handler
   * 
   * @text The packet handler responds to various HID events.
   */
  
  /* LISTING_START(packetHandler): Packet Handler */
  static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)
  {
      /* LISTING_PAUSE */
      UNUSED(channel);
      UNUSED(size);
  
      uint8_t   event;
      bd_addr_t event_addr;
      uint8_t   status;
  
      /* LISTING_RESUME */
      switch (packet_type) {
  		case HCI_EVENT_PACKET:
              event = hci_event_packet_get_type(packet);
              
              switch (event) {            
  #ifndef HAVE_BTSTACK_STDIN
                  /* @text When BTSTACK_EVENT_STATE with state HCI_STATE_WORKING
                   * is received and the example is started in client mode, the remote SDP HID query is started.
                   */
                  case BTSTACK_EVENT_STATE:
                      if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){
                          status = hid_host_connect(remote_addr, hid_host_report_mode, &hid_host_cid);
                          if (status != ERROR_CODE_SUCCESS){
                              printf("HID host connect failed, status 0x%02x.\n", status);
                          }
                      }
                      break;
  #endif
                  /* LISTING_PAUSE */
                  case HCI_EVENT_PIN_CODE_REQUEST:
  					// inform about pin code request
                      printf("Pin code request - using '0000'\n");
                      hci_event_pin_code_request_get_bd_addr(packet, event_addr);
                      gap_pin_code_response(event_addr, "0000");
  					break;
  
                  case HCI_EVENT_USER_CONFIRMATION_REQUEST:
                      // inform about user confirmation request
                      printf("SSP User Confirmation Request with numeric value '%"PRIu32"'\n", little_endian_read_32(packet, 8));
                      printf("SSP User Confirmation Auto accept\n");
                      break;
  
                  /* LISTING_RESUME */
                  case HCI_EVENT_HID_META:
                      switch (hci_event_hid_meta_get_subevent_code(packet)){
  
                          case HID_SUBEVENT_INCOMING_CONNECTION:
                              // There is an incoming connection: we can accept it or decline it.
                              // The hid_host_report_mode in the hid_host_accept_connection function 
                              // allows the application to request a protocol mode. 
                              // For available protocol modes, see hid_protocol_mode_t in hid.h file. 
                              hid_host_accept_connection(hid_subevent_incoming_connection_get_hid_cid(packet), hid_host_report_mode);
                              break;
                          
                          case HID_SUBEVENT_CONNECTION_OPENED:
                              // The status field of this event indicates if the control and interrupt
                              // connections were opened successfully.
                              status = hid_subevent_connection_opened_get_status(packet);
                              if (status != ERROR_CODE_SUCCESS) {
                                  printf("Connection failed, status 0x%x\n", status);
                                  app_state = APP_IDLE;
                                  hid_host_cid = 0;
                                  return;
                              }
                              app_state = APP_CONNECTED;
                              hid_host_descriptor_available = false;
                              hid_host_cid = hid_subevent_connection_opened_get_hid_cid(packet);
                              printf("HID Host connected.\n");
                              break;
  
                          case HID_SUBEVENT_DESCRIPTOR_AVAILABLE:
                              // This event will follows HID_SUBEVENT_CONNECTION_OPENED event. 
                              // For incoming connections, i.e. HID Device initiating the connection,
                              // the HID_SUBEVENT_DESCRIPTOR_AVAILABLE is delayed, and some HID  
                              // reports may be received via HID_SUBEVENT_REPORT event. It is up to 
                              // the application if these reports should be buffered or ignored until 
                              // the HID descriptor is available.
                              status = hid_subevent_descriptor_available_get_status(packet);
                              if (status == ERROR_CODE_SUCCESS){
                                  hid_host_descriptor_available = true;
                                  printf("HID Descriptor available, please start typing.\n");
                              } else {
                                  printf("Cannot handle input report, HID Descriptor is not available.\n");
                              }
                              break;
  
                          case HID_SUBEVENT_REPORT:
                              // Handle input report.
                              if (hid_host_descriptor_available){
                                  hid_host_handle_interrupt_report(hid_subevent_report_get_report(packet), hid_subevent_report_get_report_len(packet));
                              } else {
                                  printf_hexdump(hid_subevent_report_get_report(packet), hid_subevent_report_get_report_len(packet));
                              }
                              break;
  
                          case HID_SUBEVENT_SET_PROTOCOL_RESPONSE:
                              // For incoming connections, the library will set the protocol mode of the
                              // HID Device as requested in the call to hid_host_accept_connection. The event 
                              // reports the result. For connections initiated by calling hid_host_connect, 
                              // this event will occur only if the established report mode is boot mode.
                              status = hid_subevent_set_protocol_response_get_handshake_status(packet);
                              if (status != HID_HANDSHAKE_PARAM_TYPE_SUCCESSFUL){
                                  printf("Error set protocol, status 0x%02x\n", status);
                                  break;
                              }
                              switch ((hid_protocol_mode_t)hid_subevent_set_protocol_response_get_protocol_mode(packet)){
                                  case HID_PROTOCOL_MODE_BOOT:
                                      printf("Protocol mode set: BOOT.\n");
                                      break;  
                                  case HID_PROTOCOL_MODE_REPORT:
                                      printf("Protocol mode set: REPORT.\n");
                                      break;
                                  default:
                                      printf("Unknown protocol mode.\n");
                                      break; 
                              }
                              break;
  
                          case HID_SUBEVENT_CONNECTION_CLOSED:
                              // The connection was closed.
                              hid_host_cid = 0;
                              hid_host_descriptor_available = false;
                              printf("HID Host disconnected.\n");
                              break;
                          
                          default:
                              break;
                      }
                      break;
                  default:
                      break;
              }
              break;
          default:
              break;
      }
  }
  /* LISTING_END */
  
  #ifdef HAVE_BTSTACK_STDIN
  static void show_usage(void){
      bd_addr_t      iut_address;
      gap_local_bd_addr(iut_address);
      printf("\n--- Bluetooth HID Host Console %s ---\n", bd_addr_to_str(iut_address));
      printf("c      - Connect to %s in report mode, with fallback to boot mode.\n", remote_addr_string);
      printf("C      - Disconnect\n");
      
      printf("\n");
      printf("Ctrl-c - exit\n");
      printf("---\n");
  }
  
  static void stdin_process(char cmd){
      uint8_t status = ERROR_CODE_SUCCESS;
      switch (cmd){
          case 'c':
              printf("Connect to %s in report mode, with fallback to boot mode.\n", remote_addr_string);
              status = hid_host_connect(remote_addr, hid_host_report_mode, &hid_host_cid);
              break;
          case 'C':
              printf("Disconnect...\n");
              hid_host_disconnect(hid_host_cid);
              break;
          case '\n':
          case '\r':
              break;
          default:
              show_usage();
              break;
      }
      if (status != ERROR_CODE_SUCCESS){
          printf("HID host cmd \'%c\' failed, status 0x%02x\n", cmd, status);
      }
  }
  #endif
  
  int btstack_main(int argc, const char * argv[]);
  int btstack_main(int argc, const char * argv[]){
  
      (void)argc;
      (void)argv;
  
      hid_host_setup();
  
      // parse human readable Bluetooth address
      sscanf_bd_addr(remote_addr_string, remote_addr);
  
  #ifdef HAVE_BTSTACK_STDIN
      btstack_stdin_setup(stdin_process);
  #endif
  
      // Turn on the device 
      hci_power_control(HCI_POWER_ON);
      return 0;
  }
  
  /* EXAMPLE_END */
  