#include <string.h>
#include "app/iap.h"
#include "app/nv_storage.h"
#include "bsp/fmc_flash.h"

static int iap_write_image(uint8_t *data, int len);
static int iap_check_image(uint8_t *data, int len);
void _reboot_timer_handler(shark_timer_t *t);
void iap_read_string(can_frame_t *frame);

static u8 _write_success = 0;
static int _write_position = 0;
static shark_timer_t _reboot_timer = {.handler = _reboot_timer_handler,};

void process_iap_message(can_frame_t *frame, int len){
	uint8_t *data = NULL;
	int data_len = 0;
	switch(frame->key) {
		case CAN_KEY_IAP_ENTER:
			if (gd32_flash_size() < 128 * 1024){
				wdog_reload();
				fmc_iap_write_magic(0xFFFFFFFF);
				NVIC_SystemReset();
				while(1);
			}
			protocol_send_ack(frame->head.can_addr, frame->key, 0);
			break;
		case CAN_KEY_IAP_BEGIN:
			if (gd32_flash_size() < 128 * 1024){
				protocol_send_ack(frame->head.can_addr, frame->key, 1);
				break;
			}
			fmc_write_image_begin();
			_write_position = 0;
			_write_success = 0;
			protocol_send_ack(frame->head.can_addr, frame->key, 0);
			break;
		case CAN_KEY_IAP_WRITE:
			_write_success = 0;
			data_len = iap_write_image(frame->data, len);
			data = frame->data;
			break;
		case CAN_KEY_IAP_CHECK:
			fmc_write_image_end();
			data_len = iap_check_image(frame->data, len);
			data = frame->data;
			break;
		case CAN_KEY_IAP_BOOT:
			if (_write_success) {
				NVIC_SystemReset();
				while(1);
			} else {
				protocol_send_ack(frame->head.can_addr, frame->key, 0);
			}
			break;
		case CAN_KEY_IAP_STAT:
			protocol_send_ack(frame->head.can_addr, frame->key, 0);
			break;
		case CAN_EEY_IAP_READ_STRING:
			iap_read_string(frame);
			break;
		case CAN_KEY_REBOOT:
			if (len == 4 && shark_decode_u32(frame->data) == SHARK_IAP_MAGIC_SUCCESS) {
				fmc_iap_write_magic(0xFFFFFFFF);
			}

			shark_timer_post(&_reboot_timer, 100);
			protocol_send_ack(frame->head.can_addr, frame->key, 1);
			break;
		case CAN_KET_ERASE_NV:
			nv_erase();
			shark_timer_post(&_reboot_timer, 100);
			protocol_send_ack(frame->head.can_addr, frame->key, 1);
			break;
	}
	if (data != NULL && data_len > 0){
		protocol_send_bms_info(frame->head.can_addr, frame->key, frame->data, data_len);
	}
}

void _reboot_timer_handler(shark_timer_t *t){
	NVIC_SystemReset();
}

static int iap_write_image(uint8_t *data, int len){
	int w_pos = shark_decode_u24(data);

	if (w_pos == _write_position && len > 3) {
		fmc_write_image_continue(data + 3, len - 3);
		_write_position += len - 3;
	}
	data[0] = 0;
	shark_encode_u24(data+1, _write_position);
	return 4;
}

void iap_read_string(can_frame_t *frame)
{
	uint8_t buff[64];
	const char *text;
	uint32_t addr;
	uint32_t len;

	addr = ((uint32_t) frame->data[2]) << 16 | ((uint32_t) frame->data[1]) << 8 | frame->data[0];
	text = (const char *) (0x08000000 + addr);

	len = strlen(text);
	if (len > (sizeof(buff)-4)) {
		len = sizeof(buff) - 4;
	}
	buff[0] = 0;
	memcpy(buff+1, frame->data, 3);
	memcpy(buff + 4, text, len);

	protocol_send_bms_info(frame->head.can_addr, frame->key, buff, len + 4);
}


static int iap_check_image(uint8_t *data, int len) {
	uint32_t size, checksum;
	size = shark_decode_u24(data);
	checksum = shark_decode_u32(data + 3);
	uint32_t d_checksum = shark_iap_checksum_init();
	d_checksum = shark_iap_checksum_put(d_checksum, (const u8 *)fmc_iap_image_addr(), size);
	d_checksum = shark_iap_checksum_finish(d_checksum);

	if (checksum != d_checksum) {
		data[0] = 1;
		return 1;
	}
	fmc_write_magic(size, checksum, SHARK_IAP_MAGIC_FLASH);
	_write_success = 1;
	data[0] = 0;
	return 1;	
}