/*
 * Copyright (C) 2020 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__ "hog_host_test.c"

/*
 * hog_host_test.c
 */


#include <inttypes.h>
#include <stdio.h>
#include <btstack_tlv.h>

#include "btstack_config.h"
#include "btstack.h"

// TAG to store remote device address and type in TLV
#define TLV_TAG_HOGD ((((uint32_t) 'H') << 24 ) | (((uint32_t) 'O') << 16) | (((uint32_t) 'G') << 8) | 'D')

typedef struct {
    bd_addr_t addr;
    bd_addr_type_t addr_type;
} le_device_addr_t;

static enum {
    IDLE,
    W4_WORKING,
    W4_CONNECTED,
    W4_ENCRYPTED,
    W4_CLIENT_CONNECTED,
    READY
} app_state;

// PTS:      
static const char * device_addr_string = "00:1B:DC:08:E2:5C";

static le_device_addr_t remote_device;
static hci_con_handle_t connection_handle;
static uint16_t hids_cid;
static uint16_t battery_service_cid;

static bool connect_hids_client = false;
static bool connect_battery_client = false;
static bool connect_device_information_client = false;

static hid_protocol_mode_t protocol_mode = HID_PROTOCOL_MODE_REPORT;

// SDP
static uint8_t hid_descriptor_storage[500];

// register for events from HCI/GAP and SM
static btstack_packet_callback_registration_t hci_event_callback_registration;
static btstack_packet_callback_registration_t sm_event_callback_registration;

static void hid_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
static void battery_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
static void device_information_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);


// used to store remote device in TLV
static const btstack_tlv_t * btstack_tlv_singleton_impl;
static void *                btstack_tlv_singleton_context;

// 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 */
};

/**
 * @section HOG Boot Keyboard Handler
 * @text Boot Keyboard Input Report contains a report of format
 * [ modifier, reserved, 6 x usage for key 1..6 from keyboard usage]
 * Track new usages, map key usage to actual character and simulate terminal
 */


#define NUM_KEYS 6
static uint8_t last_keys[NUM_KEYS];
static void hid_handle_input_report(uint8_t service_index, const uint8_t * report, uint16_t report_len){
    // check if HID Input Report
    
    // printf("Report\n");
    // printf_hexdump(report, report_len);

    // printf("Descriptor\n");
    // printf_hexdump(hids_client_descriptor_storage_get_descriptor_data(hids_cid, service_index), hids_client_descriptor_storage_get_descriptor_len(hids_cid, service_index));

    if (report_len < 1) return;
    
    btstack_hid_parser_t parser;
    
    switch (protocol_mode){
        case HID_PROTOCOL_MODE_BOOT:
            
            btstack_hid_parser_init(&parser, 
                hids_client_descriptor_storage_get_descriptor_data(hids_cid, service_index), 
                hids_client_descriptor_storage_get_descriptor_len(hids_cid, service_index), 
                HID_REPORT_TYPE_INPUT, report, report_len);
            break;

        default:
            btstack_hid_parser_init(&parser, 
                hids_client_descriptor_storage_get_descriptor_data(hids_cid, service_index), 
                hids_client_descriptor_storage_get_descriptor_len(hids_cid, service_index), 
                HID_REPORT_TYPE_INPUT, report, report_len);
            break;

    }
    
    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);
}

/**
 * In case of error, disconnect and start scanning again
 */
static void handle_outgoing_connection_error(void){
    printf("Error occurred, disconnect and start over\n");
    gap_disconnect(connection_handle);
}

static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    UNUSED(channel);
    UNUSED(size);
    uint8_t event;
    switch (packet_type) {
        case HCI_EVENT_PACKET:
            event = hci_event_packet_get_type(packet);
            switch (event) {
                case BTSTACK_EVENT_STATE:
                    if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break;
                    btstack_assert(app_state == W4_WORKING);
                    break;
                
                case HCI_EVENT_DISCONNECTION_COMPLETE:
                    if (app_state != READY) break;
                    connection_handle = HCI_CON_HANDLE_INVALID;
                    printf("\nDisconnected\n");
                    app_state = IDLE;
                    break;
                
                case HCI_EVENT_LE_META:
                    // wait for connection complete
                    if (hci_event_le_meta_get_subevent_code(packet) != HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
                    if (app_state != W4_CONNECTED) return;
                    connection_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
                    // request security
                    app_state = W4_ENCRYPTED;
                    sm_request_pairing(connection_handle);
                    break;
                
                case HCI_EVENT_ENCRYPTION_CHANGE:
                    if (connection_handle != hci_event_encryption_change_get_connection_handle(packet)) break;
                    printf("Connection encrypted: %u\n", hci_event_encryption_change_get_encryption_enabled(packet));
                    if (hci_event_encryption_change_get_encryption_enabled(packet) == 0){
                        printf("Encryption failed -> abort\n");
                        handle_outgoing_connection_error();
                        break;
                    }
                    // continue - query primary services
                    printf("Search for HID service.\n");
                    app_state = W4_CLIENT_CONNECTED;
                    if (connect_hids_client){
                        connect_hids_client = false;
                        (void) hids_client_connect(connection_handle, hid_service_gatt_client_event_handler, protocol_mode, &hids_cid);
                    }

                    if (connect_battery_client){
                        connect_battery_client = false;
                        (void) battery_service_client_connect(connection_handle, battery_service_gatt_client_event_handler, 2000, &battery_service_cid);
                    }

                    if (connect_device_information_client){
                        connect_device_information_client = false;
                        (void) device_information_service_client_query(connection_handle, device_information_service_gatt_client_event_handler);
                    }
                    break;
                default:
                    break;
            }
            break;
        default:
            break;
    }
}


static void sm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    UNUSED(channel);
    UNUSED(size);

    if (packet_type != HCI_EVENT_PACKET) return;

    switch (hci_event_packet_get_type(packet)) {
        case SM_EVENT_JUST_WORKS_REQUEST:
            printf("Just works requested\n");
            sm_just_works_confirm(sm_event_just_works_request_get_handle(packet));
            break;
        case SM_EVENT_NUMERIC_COMPARISON_REQUEST:
            printf("Confirming numeric comparison: %"PRIu32"\n", sm_event_numeric_comparison_request_get_passkey(packet));
            sm_numeric_comparison_confirm(sm_event_passkey_display_number_get_handle(packet));
            break;
        case SM_EVENT_PASSKEY_DISPLAY_NUMBER:
            printf("Display Passkey: %"PRIu32"\n", sm_event_passkey_display_number_get_passkey(packet));
            break;
        case SM_EVENT_PAIRING_COMPLETE:
            switch (sm_event_pairing_complete_get_status(packet)){
                case ERROR_CODE_SUCCESS:
                    printf("Pairing complete, success\n");
                    break;
                case ERROR_CODE_CONNECTION_TIMEOUT:
                    printf("Pairing failed, timeout\n");
                    break;
                case ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION:
                    printf("Pairing faileed, disconnected\n");
                    break;
                case ERROR_CODE_AUTHENTICATION_FAILURE:
                    printf("Pairing failed, reason = %u\n", sm_event_pairing_complete_get_reason(packet));
                    break;
                default:
                    break;
            }
            break;
        default:
            break;
    }
}


static void hid_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) {
    UNUSED(packet_type);
    UNUSED(channel);
    UNUSED(size);

    uint8_t status;

    if (hci_event_packet_get_type(packet) != HCI_EVENT_GATTSERVICE_META){
        return;
    }
    
    switch (hci_event_gattservice_meta_get_subevent_code(packet)){
        case GATTSERVICE_SUBEVENT_HID_SERVICE_CONNECTED:
            status = gattservice_subevent_hid_service_connected_get_status(packet);
            switch (status){
                case ERROR_CODE_SUCCESS:
                    printf("HID service client connected, found %d services\n", 
                        gattservice_subevent_hid_service_connected_get_num_instances(packet));
        
                                        // store device as bonded
                    if (btstack_tlv_singleton_impl){
                        btstack_tlv_singleton_impl->store_tag(btstack_tlv_singleton_context, TLV_TAG_HOGD, (const uint8_t *) &remote_device, sizeof(remote_device));
                    }
                    // done
                    printf("Ready - please start typing or mousing..\n");
                    app_state = READY;
                    break;
                default:
                    printf("HID service client connection failed, err 0x%02x.\n", status);
                    handle_outgoing_connection_error();
                    break;
            }
            break;

        case GATTSERVICE_SUBEVENT_HID_REPORT:
            hid_handle_input_report(
                gattservice_subevent_hid_report_get_service_index(packet),
                gattservice_subevent_hid_report_get_report(packet), 
                gattservice_subevent_hid_report_get_report_len(packet));
            break;

        default:
            break;
    }
}

static void device_information_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    /* LISTING_PAUSE */
    UNUSED(packet_type);
    UNUSED(channel);
    UNUSED(size);
    
    if (hci_event_packet_get_type(packet) != HCI_EVENT_GATTSERVICE_META){
        return;
    }
    uint8_t status;
    switch (hci_event_gattservice_meta_get_subevent_code(packet)){
        case GATTSERVICE_SUBEVENT_DEVICE_INFORMATION_DONE:
            status = gattservice_subevent_device_information_done_get_att_status(packet);
            switch (status){
                case ERROR_CODE_SUCCESS:
                    app_state = READY;
                    printf("Device Information service found\n");
                    break;
                default:
                    printf("Device Information service client connection failed, err 0x%02x.\n", status);
                    gap_disconnect(connection_handle);
                    break;
            }
            break;
        default:    
            break;
    }

}

static void battery_service_gatt_client_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    /* LISTING_PAUSE */
    UNUSED(packet_type);
    UNUSED(channel);
    UNUSED(size);

    /* LISTING_RESUME */
    uint8_t status;
    uint8_t att_status;

    if (hci_event_packet_get_type(packet) != HCI_EVENT_GATTSERVICE_META){
        return;
    }
    
    switch (hci_event_gattservice_meta_get_subevent_code(packet)){
        case GATTSERVICE_SUBEVENT_BATTERY_SERVICE_CONNECTED:
            status = gattservice_subevent_battery_service_connected_get_status(packet);
            switch (status){
                case ERROR_CODE_SUCCESS:
                    app_state = READY;
                    printf("Battery service client connected, found %d services, poll bitmap 0x%02x\n", 
                        gattservice_subevent_battery_service_connected_get_num_instances(packet),
                        gattservice_subevent_battery_service_connected_get_poll_bitmap(packet));
                    break;
                default:
                    printf("Battery service client connection failed, err 0x%02x.\n", status);
                    gap_disconnect(connection_handle);
                    break;
            }
            break;

        case GATTSERVICE_SUBEVENT_BATTERY_SERVICE_LEVEL:
            att_status = gattservice_subevent_battery_service_level_get_att_status(packet);
            if (att_status != ATT_ERROR_SUCCESS){
                printf("Battery level read failed, ATT Error 0x%02x\n", att_status);
            } else {
                printf("Service index: %d, Battery level: %d\n", 
                    gattservice_subevent_battery_service_level_get_sevice_index(packet), 
                    gattservice_subevent_battery_service_level_get_level(packet));
                    
            }
            break;

        default:
            break;
    }
}

#ifdef HAVE_BTSTACK_STDIN

// On systems with STDIN, we can directly type on the console
static void show_usage(void){
    bd_addr_t      iut_address;
    gap_local_bd_addr(iut_address);
    printf("\n--- Bluetooth HOG Host Test Console %s ---\n", bd_addr_to_str(iut_address));
    printf("c      - connect to remote device\n");
    printf("C      - disconnect from remote device\n");
    
    printf("h      - connect to HID Service client\n");
    printf("b      - connect to Battery Service Client\n");
    printf("d      - connect to Device Information Service Client\n");
    printf("Ctrl-c - exit\n");
    printf("---\n");
}

static void hog_host_connect_hids_client(void){
    app_state = W4_CONNECTED;
    printf("Connect to remote device\n");
    connect_hids_client = true;
    gap_connect(remote_device.addr, remote_device.addr_type);
}

static void hog_host_connect_battery_client(void){
    app_state = W4_CONNECTED;
    printf("Connect to remote device\n");
    connect_battery_client = true;
    gap_connect(remote_device.addr, remote_device.addr_type);
}

static void hog_host_connect_device_information_client(void){
    app_state = W4_CONNECTED;
    printf("Connect to remote device\n");
    connect_device_information_client = true;
    gap_connect(remote_device.addr, remote_device.addr_type);
}

static void stdin_process(char character){

    switch (character){
        case 'c':
            app_state = W4_CONNECTED;
            printf("Connect to remote device\n");
            gap_connect(remote_device.addr, remote_device.addr_type);
            break;
        
        case 'C':
            printf("Disconnect from remote device\n");
            gap_disconnect(connection_handle);
            break;

        case 'h':
            printf("Connect to HID Service Client\n");
            hog_host_connect_hids_client();
            break;
        
        case 'b':
            printf("Connect to Battery Service\n");
            hog_host_connect_battery_client();
            return;
        
        case 'd':
            printf("Connect to Device Information Service\n");
            hog_host_connect_device_information_client();
            break;
        case '\n':
        case '\r':
            break;
        default:
            show_usage();
            break;
    }
}
#endif

int btstack_main(int argc, const char * argv[]);
int btstack_main(int argc, const char * argv[]){

    (void)argc;
    (void)argv;

    // register for events from HCI
    hci_event_callback_registration.callback = &packet_handler;
    hci_add_event_handler(&hci_event_callback_registration);

    // register for events from Security Manager
    sm_event_callback_registration.callback = &sm_packet_handler;
    sm_add_event_handler(&sm_event_callback_registration);

    // setup le device db
    le_device_db_init();

    //
    l2cap_init();
    sm_init();
    gatt_client_init();

    hids_client_init(hid_descriptor_storage, sizeof(hid_descriptor_storage));

    /* LISTING_END */

    // Disable stdout buffering
    setbuf(stdout, NULL);

    app_state = W4_WORKING;

    // Parse human readable Bluetooth address.
    sscanf_bd_addr(device_addr_string, remote_device.addr);
    remote_device.addr_type = BD_ADDR_TYPE_LE_PUBLIC;

    btstack_stdin_setup(stdin_process);
    // Turn on the device
    hci_power_control(HCI_POWER_ON);
    return 0;
}