#include "OTA.h"
#include "gd32c10x_fmc.h"
#include "systick.h"
#include <cstdio>
#include <cstring>
#include <flash.h>
#include <stdint.h>

extern CAN_transmiter CAN0_transmiter; // CAN初始化
extern FlashEEPROM flashEEP;
OTAHandler ota;
extern "C" {
void canfd_rx_irq_handler(void);
}
#define DEBUG_OTA 1

void OTAHandler::init() {}

void OTAHandler::process() {
	if (!ota_active) {
		ota_time = 0; // 重置计时器
		static u8 zero[1] = {ota_active};
		CAN0_transmiter.CANFD_AsyncSend(CANFD_OTA_WAIT_ID, 0, zero);
#ifdef DEBUG_OTA
		printf("wait OTA%d\r\n", ota_active);
#endif
		delay_1ms(10);
		return;
	} else {
		delay_1ms(1);
		ota_time++;
	}

	// 检查是否超时（例如：10秒无数据则退出OTA模式）
	if (ota_time > 10000) { // 10秒超时（10000 x 1ms）
		ota_time = 0;
		ota_active = false;
	}
}

bool OTAHandler::validateApplication() {
	u32 *app_vector = (u32 *)APP_START_ADDR;
	u32 stack_ptr = app_vector[0];
	u32 reset_handler = app_vector[1];

	// 简单验证：检查栈指针是否在SRAM范围内
	return (stack_ptr >= 0x20000000 && stack_ptr < 0x20008000) &&
		   (reset_handler >= APP_START_ADDR &&
			reset_handler < (APP_START_ADDR + APP_MAX_SIZE));
}

void OTAHandler::jumpToApplication() {
    if (!validateApplication()) return;
    
    // 1. 关闭所有中断
    __disable_irq();
    for (int i = 0; i < 8; i++) {
        NVIC->ICER[i] = 0xFFFFFFFF;
    }
    
    // 2. 重置外设（特别是CAN，防止冲突）
    can_deinit(CAN0);
    
    // 3. 重置系统时钟到默认状态
    rcu_system_clock_source_config(RCU_CKSYSSRC_IRC8M);
    
    // 4. 关闭一些关键外设时钟
    rcu_periph_clock_disable(RCU_GPIOA);
    rcu_periph_clock_disable(RCU_GPIOB);
    rcu_periph_clock_disable(RCU_GPIOC);
    rcu_periph_clock_disable(RCU_USART0);
    rcu_periph_clock_disable(RCU_CAN0);
    rcu_periph_clock_disable(RCU_TIMER0);
    rcu_periph_clock_disable(RCU_DMA0);
    
    // 5. 设置MSP并跳转
    uint32_t msp_value = *(__IO uint32_t*)APP_START_ADDR;
    __set_MSP(msp_value);
    
    uint32_t reset_handler = *(__IO uint32_t*)(APP_START_ADDR + 4);
    typedef void (*AppEntryFunc)(void);
    AppEntryFunc app_entry = (AppEntryFunc)reset_handler;
    
    // 6. 跳转
    app_entry();
}

void OTAHandler::eraseApplicationArea() {
	// 擦除APP区域
	fmc_unlock();
	for (u32 addr = APP_START_ADDR; addr < (APP_START_ADDR + APP_MAX_SIZE);
		 addr += FMC_PAGE_SIZE) {
		fmc_page_erase(addr);
	}
	fmc_lock();
}

void OTAHandler::writeApplicationData(u32 offset, u8 *data, u32 size) {
	fmc_unlock();
	u32 write_addr = APP_START_ADDR + offset;

	// 32位对齐写入
	for (u32 i = 0; i < size; i += 4) {
		u32 word = 0;
		memcpy(&word, &data[i], 4);
		fmc_word_program(write_addr + i, word);
	}

	fmc_lock();
}

void OTAHandler::handleOTAMessage(u32 id, u8 *data, u8 len) {
	if (id == CANFD_OTA_REQ_ID) {
#ifdef DEBUG_OTA
		printf("req OTA\r\n");
#endif
		// OTA请求包
		u32 new_size = *(u32 *)data;
		if (new_size <= APP_MAX_SIZE) {
			expected_size = new_size;
			received_size = 0;
			// eraseApplicationArea();
			ota_active = true;
			sendACK(new_size); // 确认开始
#ifdef DEBUG_OTA
			printf("start OTA%d\r\n", ota_active);
#endif
		}
	} else if (id == CANFD_OTA_DATA_ID && ota_active) {
		// 数据包格式：[4字节包序号][实际数据]
		if (len >= 4) {
			u32 packet_num = *(u32 *)data;
			u32 offset = packet_num * (len - 4);

			if (offset < expected_size) {
				writeApplicationData(offset, &data[4], len - 4); // 写入数据
				received_size += (len - 4);
				sendACK(packet_num); // 确认ACK
				ota_time = 0;		 // 重置计时器

				// 检查是否完成
				if (received_size >= expected_size) {
					ota_active = false;
					// 跳转前延时让ACK发出
					for (volatile int i = 0; i < 100000; i++)
						;
					jumpToApplication();
				}
			}
		}
	}
}

void OTAHandler::sendACK(u32 packet_num) {
	CAN0_transmiter.sendACK(CANFD_OTA_ACK_ID, packet_num);
}