#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_exti.h"
#include "stm32f10x_tim.h"
#include "lcd1602.h"

// 硬件引脚定义
#define FLOW_SENSOR_PIN    GPIO_Pin_0  // PA0(外部中断)
#define STEPPER_A          GPIO_Pin_1  // PB1
#define STEPPER_B          GPIO_Pin_2  // PB2
#define BUZZER_PIN         GPIO_Pin_3  // PB3
#define KEY_SET            GPIO_Pin_4  // PB4(设置键)

// 系统参数
#define FLOW_CALIB_FACTOR 7.5f        // 流量校准系数(L/min/Hz)
#define SAMPLE_INTERVAL   1000         // 流量采样间隔(ms)
#define FLOW_TOLERANCE    0.5f         // 流量偏差阈值(L)

// 全局变量
volatile uint32_t pulse_count = 0;      // 流量脉冲计数
float current_flow = 0.0f;              // 当前流量(L/min)
float target_flow = 1.0f;               // 目标流量(L/min)
uint8_t system_mode = 0;                // 系统模式(0:停机 1:运行)
uint8_t alarm_flag = 0;                // 报警标志

// 步进电机相位表(四相四拍)
const uint8_t phase_table[4] = {0x01, 0x02, 0x04, 0x08};

// PID参数
typedef struct {
    float Kp, Ki, Kd;
    float integral;
    float prev_error;
} PID_Controller;

PID_Controller pid = {0.8, 0.05, 0.1, 0, 0};

/***************************** 硬件初始化 *****************************/
void HW_Init(void) {
    GPIO_InitTypeDef GPIO_InitStruct;

    // 启用时钟
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);

    // 流量传感器输入(浮空输入)
    GPIO_InitStruct.GPIO_Pin = FLOW_SENSOR_PIN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    // 步进电机输出(推挽输出)
    GPIO_InitStruct.GPIO_Pin = STEPPER_A | STEPPER_B;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStruct);

    // 蜂鸣器控制
    GPIO_InitStruct.GPIO_Pin = BUZZER_PIN;
    GPIO_Init(GPIOB, &GPIO_InitStruct);

    // 外部中断配置(PA0)
    EXTI_InitTypeDef EXTI_InitStruct = {
        .EXTI_Line = EXTI_Line0,
        .EXTI_Mode = EXTI_Mode_Interrupt,
        .EXTI_Trigger = EXTI_Trigger_Rising,
        .EXTI_LineCmd = ENABLE
    };
    EXTI_Init(&EXTI_InitStruct);

    NVIC_InitTypeDef NVIC_InitStruct = {
        .NVIC_IRQChannel = EXTI0_IRQn,
        .NVIC_IRQChannelPreemptionPriority = 0,
        .NVIC_IRQChannelSubPriority = 0,
        .NVIC_IRQChannelCmd = ENABLE
    };
    NVIC_Init(&NVIC_InitStruct);

    // 定时器3配置(1ms中断)
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
    TIM_TimeBaseInitTypeDef TIM_InitStruct = {
        .TIM_Prescaler = 7200 - 1,     // 72MHz/7200=10kHz
        .TIM_CounterMode = TIM_CounterMode_Up,
        .TIM_Period = 10000 - 1,       // 1秒周期
        .TIM_ClockDivision = TIM_CKD_DIV1
    };
    TIM_TimeBaseInit(TIM3, &TIM_InitStruct);
    TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
    TIM_Cmd(TIM3, ENABLE);

    NVIC_InitStruct.NVIC_IRQChannel = TIM3_IRQn;
    NVIC_Init(&NVIC_InitStruct);
}

/***************************** PID计算 *****************************/
float PID_Compute(float setpoint, float input) {
    float error = setpoint - input;
    pid.integral += error;
    float derivative = error - pid.prev_error;
    pid.prev_error = error;
    return pid.Kp*error + pid.Ki*pid.integral + pid.Kd*derivative;
}

/***************************** 步进电机控制 *****************************/
void Stepper_Drive(int steps) {
    static uint8_t phase = 0;
    static uint32_t last_step = 0;

    if(steps != 0 && (HAL_GetTick() - last_step) > 10) {  // 10ms步间隔
        phase = (phase + (steps > 0 ? 1 : 3)) % 4;        // 正反转控制
        GPIOB->ODR = (GPIOB->ODR & 0xFFF0) | (phase_table[phase] >> 1);
        last_step = HAL_GetTick();
    }
}

/***************************** 中断服务程序 *****************************/
void EXTI0_IRQHandler(void) {
    if(EXTI_GetITStatus(EXTI_Line0) != RESET) {
        pulse_count++;  // 脉冲计数
        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}

void TIM3_IRQHandler(void) {
    if(TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET) {
        // 计算实时流量
        current_flow = (pulse_count / FLOW_CALIB_FACTOR) * (60000.0 / SAMPLE_INTERVAL);
        pulse_count = 0;

        TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
    }
}

/***************************** 主程序 *****************************/
int main(void) {
    // 初始化阶段
    SystemInit();
    HW_Init();
    LCD_Init();
    __enable_irq();

    // 主循环
    while(1) {
        // 按键处理
        if(GPIO_ReadInputDataBit(GPIOB, KEY_SET) == Bit_RESET) {
            DelayMs(20);
            if(GPIO_ReadInputDataBit(GPIOB, KEY_SET) == Bit_RESET) {
                system_mode ^= 0x01;
                while(GPIO_ReadInputDataBit(GPIOB, KEY_SET) == Bit_RESET);
            }
        }

        // 运行模式控制
        if(system_mode) {
            float control = PID_Compute(target_flow, current_flow);
            Stepper_Drive((int)control);

            // 异常检测
            alarm_flag = (fabs(current_flow - target_flow) > FLOW_TOLERANCE);
        } else {
            Stepper_Drive(0);
            alarm_flag = 0;
        }

        // 显示更新
        char buf[17];
        snprintf(buf, sizeof(buf), "Flow:%5.2f L/m", current_flow);
        LCD_Write_String(0, 0, buf);
        snprintf(buf, sizeof(buf), "Target:%5.1f L/m", target_flow);
        LCD_Write_String(0, 1, buf);

        // 报警控制
        GPIO_WriteBit(GPIOB, BUZZER_PIN, alarm_flag ? Bit_SET : Bit_RESET);
    }
}