/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2019 Ha Thach (tinyusb.org)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 */

/*
  * After device is enumerated in dfu mode run the following commands
  *
  * To transfer firmware from host to device (best to test with text file)
  *
  * $ dfu-util -d cafe -a 0 -D [filename]
  * $ dfu-util -d cafe -a 1 -D [filename]
  *
  * To transfer firmware from device to host:
  *
  * $ dfu-util -d cafe -a 0 -U [filename]
  * $ dfu-util -d cafe -a 1 -U [filename]
  *
  */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "bsp/board_api.h"
#include "tusb.h"

//--------------------------------------------------------------------+
// MACRO CONSTANT TYPEDEF PROTYPES
//--------------------------------------------------------------------+
const char *upload_image[2] = {"Hello world from TinyUSB DFU! - Partition 0",
                               "Hello world from TinyUSB DFU! - Partition 1"};

/* Blink pattern
 * - 250 ms  : device not mounted
 * - 1000 ms : device mounted
 * - 2500 ms : device is suspended
 */
enum {
  BLINK_NOT_MOUNTED = 250,
  BLINK_MOUNTED     = 1000,
  BLINK_SUSPENDED   = 2500,
};

static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;

void led_blinking_task(void);

/*------------- MAIN -------------*/
int main(void) {
  board_init();

  // init device stack on configured roothub port
  tusb_rhport_init_t dev_init = {.role = TUSB_ROLE_DEVICE, .speed = TUSB_SPEED_AUTO};
  tusb_init(BOARD_TUD_RHPORT, &dev_init);

  board_init_after_tusb();

  while (1) {
    tud_task(); // tinyusb device task
    led_blinking_task();
  }
}

//--------------------------------------------------------------------+
// Device callbacks
//--------------------------------------------------------------------+

// Invoked when device is mounted
void tud_mount_cb(void) {
  blink_interval_ms = BLINK_MOUNTED;
}

// Invoked when device is unmounted
void tud_umount_cb(void) {
  blink_interval_ms = BLINK_NOT_MOUNTED;
}

// Invoked when usb bus is suspended
// remote_wakeup_en : if host allow us  to perform remote wakeup
// Within 7ms, device must draw an average of current less than 2.5 mA from bus
void tud_suspend_cb(bool remote_wakeup_en) {
  (void)remote_wakeup_en;
  blink_interval_ms = BLINK_SUSPENDED;
}

// Invoked when usb bus is resumed
void tud_resume_cb(void) {
  blink_interval_ms = tud_mounted() ? BLINK_MOUNTED : BLINK_NOT_MOUNTED;
}

//--------------------------------------------------------------------+
// DFU callbacks
// Note: alt is used as the partition number, in order to support multiple partitions like FLASH, EEPROM, etc.
//--------------------------------------------------------------------+

// Invoked right before tud_dfu_download_cb() (state=DFU_DNBUSY) or tud_dfu_manifest_cb() (state=DFU_MANIFEST)
// Application return timeout in milliseconds (bwPollTimeout) for the next download/manifest operation.
// During this period, USB host won't try to communicate with us.
uint32_t tud_dfu_get_timeout_cb(uint8_t alt, uint8_t state) {
  if (state == DFU_DNBUSY) {
    // For this example
    // - Atl0 Flash is fast : 1   ms
    // - Alt1 EEPROM is slow: 100 ms
    return (alt == 0) ? 1 : 100;
  } else if (state == DFU_MANIFEST) {
    // since we don't buffer entire image and do any flashing in manifest stage
    return 0;
  } else {
    // nothing to do
  }

  return 0;
}

// Invoked when received DFU_DNLOAD (wLength>0) following by DFU_GETSTATUS (state=DFU_DNBUSY) requests
// This callback could be returned before flashing op is complete (async).
// Once finished flashing, application must call tud_dfu_finish_flashing()
void tud_dfu_download_cb(uint8_t alt, uint16_t block_num, const uint8_t *data, uint16_t length) {
  (void)alt;
  (void)block_num;

  //printf("\r\nReceived Alt %u BlockNum %u of length %u\r\n", alt, wBlockNum, length);

  for (uint16_t i = 0; i < length; i++) {
    printf("%c", data[i]);
  }

  // flashing op for download complete without error
  tud_dfu_finish_flashing(DFU_STATUS_OK);
}

// Invoked when download process is complete, received DFU_DNLOAD (wLength=0) following by DFU_GETSTATUS (state=Manifest)
// Application can do checksum, or actual flashing if buffered entire image previously.
// Once finished flashing, application must call tud_dfu_finish_flashing()
void tud_dfu_manifest_cb(uint8_t alt) {
  (void)alt;
  printf("Download completed, enter manifestation\r\n");

  // flashing op for manifest is complete without error
  // Application can perform checksum, should it fail, use appropriate status such as errVERIFY.
  tud_dfu_finish_flashing(DFU_STATUS_OK);
}

// Invoked when received DFU_UPLOAD request
// Application must populate data with up to length bytes and
// Return the number of written bytes
uint16_t tud_dfu_upload_cb(uint8_t alt, uint16_t block_num, uint8_t *data, uint16_t length) {
  (void)block_num;
  (void)length;

  if (block_num != 0u) {
    return 0; // for this example we only support single block upload
  }

  const uint16_t xfer_len = tu_min16((uint16_t)strlen(upload_image[alt]), length);
  memcpy(data, upload_image[alt], xfer_len);

  return xfer_len;
}

// Invoked when the Host has terminated a download or upload transfer
void tud_dfu_abort_cb(uint8_t alt) {
  (void)alt;
  printf("Host aborted transfer\r\n");
}

// Invoked when a DFU_DETACH request is received
void tud_dfu_detach_cb(void) {
  printf("Host detach, we should probably reboot\r\n");
}

//--------------------------------------------------------------------+
// BLINKING TASK + Indicator pulse
//--------------------------------------------------------------------+

void led_blinking_task(void) {
  static uint32_t start_ms  = 0;
  static bool     led_state = false;

  // Blink every interval ms
  if (tusb_time_millis_api() - start_ms < blink_interval_ms) {
    return; // not enough time
  }
  start_ms += blink_interval_ms;

  board_led_write(led_state);
  led_state = 1 - led_state; // toggle
}