#include "tusb.h"

//--------------------------------------------------------------------
// Device Descriptor
//--------------------------------------------------------------------
tusb_desc_device_t const desc_device =
{
    .bLength            = sizeof(tusb_desc_device_t),
    .bDescriptorType    = TUSB_DESC_DEVICE,
    .bcdUSB             = 0x0200,
    .bDeviceClass       = 0x00,
    .bDeviceSubClass    = 0x00,
    .bDeviceProtocol    = 0x00,
    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,

    .idVendor           = 0xCafe,
    .idProduct          = 0x4000,
    .bcdDevice          = 0x0100,

    .iManufacturer      = 0x01,
    .iProduct           = 0x02,
    .iSerialNumber      = 0x03,

    .bNumConfigurations = 0x01
};

uint8_t const * tud_descriptor_device_cb(void) {
    return (uint8_t const *) &desc_device;
}

//--------------------------------------------------------------------
// HID Report Descriptor
//--------------------------------------------------------------------
uint8_t const desc_hid_report[] =
{
    HID_USAGE_PAGE_N ( HID_USAGE_PAGE_VENDOR, 2   ),
    HID_USAGE        ( 0x01                       ),
    HID_COLLECTION   ( HID_COLLECTION_APPLICATION ),
        // ADC Value 12-bit, sent as 2 bytes
        HID_LOGICAL_MIN  ( 0x00                     ),
        HID_LOGICAL_MAX_N( 0x0FFF, 2                ),
        HID_REPORT_SIZE  ( 8                        ),
        HID_REPORT_COUNT ( 2                        ),
        HID_USAGE        ( 0x02                     ),
        HID_INPUT        ( HID_DATA | HID_VARIABLE | HID_ABSOLUTE ),
    HID_COLLECTION_END
};

uint8_t const * tud_hid_descriptor_report_cb(uint8_t instance) {
    return desc_hid_report;
}

//--------------------------------------------------------------------
// Configuration Descriptor
//--------------------------------------------------------------------
enum {
    ITF_NUM_HID,
    ITF_NUM_TOTAL
};

#define CONFIG_TOTAL_LEN  (TUD_CONFIG_DESC_LEN + TUD_HID_DESC_LEN)
#define EPNUM_HID   0x81

uint8_t const desc_configuration[] =
{
    // Config number, interface count, string index, total length, attribute, power in mA
    TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0, 100),

    // Interface number, string index, protocol, report descriptor len, EP In address, size & polling interval
    TUD_HID_DESCRIPTOR(ITF_NUM_HID, 0, HID_ITF_PROTOCOL_NONE, sizeof(desc_hid_report), EPNUM_HID, CFG_TUD_HID_EP_BUFSIZE, 10)
};

uint8_t const * tud_descriptor_configuration_cb(uint8_t index) {
    return desc_configuration;
}

//--------------------------------------------------------------------
// String Descriptors
//--------------------------------------------------------------------
char const* string_desc_arr [] =
{
    (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409)
    "RP2040",                     // 1: Manufacturer
    "SS49E WebHID",               // 2: Product
    "123456",                     // 3: Serials
};

static uint16_t _desc_str[32];

uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
    uint8_t chr_count;

    if ( index == 0) {
        memcpy(&_desc_str[1], string_desc_arr[0], 2);
        chr_count = 1;
    } else {
        if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;

        const char* str = string_desc_arr[index];
        chr_count = strlen(str);
        if ( chr_count > 31 ) chr_count = 31;

        for(uint8_t i=0; i<chr_count; i++) {
            _desc_str[1+i] = str[i];
        }
    }

    _desc_str[0] = (TUSB_DESC_STRING << 8 ) | (2*chr_count + 2);
    return _desc_str;
}