#include <iostream>
#include <iomanip>
#include <memory>
#include <thread>
#include <chrono>
#include <functional>
#include <fcntl.h>
#include <poll.h>
#include <unistd.h>

#define I2C_SDA 43 // GPIO1_B3
#define I2C_SCL 44 // GPIO1_B4
#define I2C_INT 52

typedef unsigned char UINT8;
typedef unsigned short UINT16;

#define STATUS_SUCCESS 0
#define STATUS_FAILURE -1

#define CH455_GET_KEY 0x0700 // 获取按键,返回按键代码
#define CH455_SYSOFF 0x0400  // 关闭显示、关闭键盘

#define CH455_I2C_ADDR 0x40 // CH455的地址
#define CH455_I2C_MASK 0x3E // CH455的高字节命令掩码

#define CH455_BIT_ENABLE 0x01
// #define CH455_BIT_ENABLE	0x03		       // 开启/关闭位
#define CH455_BIT_SLEEP 0x04 // 睡眠控制位

#define CH455_SYSON (CH455_SYSOFF | CH455_BIT_ENABLE)
#define CH455_SLEEPOFF CH455_SYSOFF                    // 关闭睡眠
#define CH455_SLEEPON (CH455_SYSOFF | CH455_BIT_SLEEP) // 开启睡眠

static unsigned char TxBuf[24] = {0};
static unsigned char RxBuf[24] = {0};

void CH455_I2c_Stop(void);
void CH455_I2C_WrByte(unsigned char IIC_Byte);

void delay_us(int i)
{
    int j, k;
    for (j = 0; j < i; j++)
        for (k = 0; k < 10; k++)
            ;
}

void initGpio(int addr)
{
    // printf("开始创建GPIO%d节点\n", addr);
    FILE *fp = fopen("/sys/class/gpio/export", "w");
    if (fp == NULL)
        perror("export open filed");
    else
        fprintf(fp, "%d", addr);

    fclose(fp);
    // printf("结束创建GPIO%d节点\n", addr);
}

// 设置为gpio方向
void setGpioDirection(int addr, char *direction)
{
    // printf("设置第GPIO%d为out模式\n",addr);
    char path[100] = {0};
    sprintf(path, "/sys/class/gpio/gpio%d/direction", addr);
    FILE *fp = fopen(path, "w");
    if (fp == NULL)
        perror("direction open filed");
    else
        fprintf(fp, "%s", direction);
    fclose(fp);
    // printf("结束设置第GPIO%d为out模式\n",addr);
}

// 设置gpio的电平
void set_gpioValue(int addr, int value)
{
    // printf("设置GPIO%d为%d\n", addr, value);
    char path[64];
    snprintf(path, sizeof(path), "/sys/class/gpio/gpio%d/value", addr);
    FILE *fp = fopen(path, "w");
    if (fp == NULL)
        perror("direction open filed");
    else
        fprintf(fp, "%d", value);
    fclose(fp);
    // printf("结束设置GPIO%d位置为%d\n", addr, value);
}

void IOWR_OUT(int addr, int val)
{
    initGpio(addr);
    setGpioDirection(addr, "out");
    set_gpioValue(addr, val);
}

void IOWR_IN(int addr, int val)
{
    initGpio(addr);
    setGpioDirection(addr, "in");
    set_gpioValue(addr, val);
}

// 读gpio节点状态
int IORD(int addr)
{
    char path[64];
    char value_str[3];

    snprintf(path, sizeof(path), "/sys/class/gpio/gpio%d/value", addr);
    // printf("/sys/class/gpio/gpio%d/value", addr);
    FILE *fp = fopen(path, "r");

    // fd = open(path, O_RDONLY);
    if (fp == NULL)
    {
        printf("Failed to open gpio value for reading!");
        return -1;
    }
    if (fread(value_str, sizeof(char), 3, fp) < 0)
    {
        perror("Failed to read value!");
        return -1;
    }

    fclose(fp);
    // printf("读取GPIO状态结束\n");
    return (atoi(value_str));
}

// 开始位
void CH455_I2c_Start(void)
{
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 0);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
}

// 结束位
void CH455_I2c_Stop(void)
{
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 0);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
}

// 主控端写入一个字节到从机
void CH455_I2C_WrByte(unsigned char IIC_Byte)
{
    unsigned char i;
    for (i = 0; i < 8; i++)
    {
        // IOWR(I2C_SCL, 0); //钳住I2C总线，准备发送数据
        if (IIC_Byte & 0x80)
            IOWR_OUT(I2C_SDA, 1);
        else
            IOWR_OUT(I2C_SDA, 0);
        delay_us(5);
        IOWR_OUT(I2C_SCL, 1);
        delay_us(5);
        IOWR_OUT(I2C_SCL, 0);
        delay_us(5);
        IIC_Byte <<= 1;
    }
    delay_us(5);
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
}

// 主控端对从机读取一个字节
static unsigned char CH455_I2C_RdByte(void) // 读取一个字节数据
{
    unsigned char i = 0;
    unsigned char bytedata = 0;
    delay_us(5);
    // 将数据设置为输入模式
    IOWR_IN(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    for (i = 0; i < 8; i++)
    {
        IOWR_OUT(I2C_SCL, 1);
        delay_us(5);
        bytedata <<= 1;
        delay_us(5);
        bytedata = bytedata | (IORD(I2C_SDA));
        delay_us(5);
        IOWR_OUT(I2C_SCL, 0);
        delay_us(5);
    }
    IOWR_OUT(I2C_SDA, 1); // 数据线设置回输出模式
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    return (bytedata); // 返回数据
}

// 写命令
static unsigned char CH455_Write(UINT16 cmd)
{
    printf("CH455_Write start...\n");
    CH455_I2c_Start(); // 启动总线
    printf("CH455_Write first byte= %02x\n", ((UINT8)(cmd >> 7) & CH455_I2C_MASK) | CH455_I2C_ADDR);
    printf("CH455_Write second byte= %02x\n", (UINT8)cmd);
    CH455_I2C_WrByte(((UINT8)(cmd >> 7) & CH455_I2C_MASK) | CH455_I2C_ADDR);
    CH455_I2C_WrByte((UINT8)cmd); // 发送数据
    CH455_I2c_Stop();             // 结束总线
    printf("CH455_Write end...\n");
    printf("\n");
    return 1;
}

static unsigned char CH455_Read(void) // 读取按键值
{
    printf("CH455_Read start...\n");
    UINT8 keycode;
    CH455_I2c_Start(); // 启动总线
    printf("write byte= %02x\n", (UINT8)(CH455_GET_KEY >> 7) & CH455_I2C_MASK | 0x01 | CH455_I2C_ADDR);
    CH455_I2C_WrByte((UINT8)(CH455_GET_KEY >> 7) & CH455_I2C_MASK | 0x01 | CH455_I2C_ADDR);
    keycode = CH455_I2C_RdByte(); // 读取数据
    printf("read byte= %02x\n", keycode);
    CH455_I2c_Stop(); // 结束总线
    printf("CH455_Read end...\n");
    printf("\n");
    return keycode;
}

void key_Inter(void)
{
    int ret;
    int val = 0;
    char buf[8];
    int num;
    UINT16 key_value;
    pollfd pfd;
    pfd.fd = -1;
    pfd.fd = open("/sys/class/gpio/gpio52/value", O_RDONLY);
    if (pfd.fd > 0)
        printf("huagao::open sucess,fd = %d\n", pfd.fd);
    else
        printf("huagao::open failed,fd = %d\n", pfd.fd);
    pfd.events = POLLPRI;
    num = read(pfd.fd, buf, 8); // This is to clear the avaible read
    for (int i = 0; i < 8; i++)
        printf("huagao::buf[%d] = %d\n", i, buf[i]);

    ret = CH455_Write(CH455_SYSON);
    printf("CH455_SYSON = %02x\n", (CH455_SYSON));
    printf("CH455_Read() = %02x\n", CH455_Read());
    key_value = 0xff;
    while (1)
    {
        ret = poll(&pfd, 1, 1000);
        if (ret > 0)
        {
            printf("--------------------------------------------\n");
            printf("huagao::poll get date.\n");
            printf("huagao::poll ret = %d\n", ret);
            /*
            POLLIN: 有普通数据或者优先数据可读
            POLLRDNORM: 有普通数据可读
            POLLRDBAND: 有优先数据可读
            POLLPRI: 有紧急数据可读
            POLLOUT: 有普通数据可写
            POLLWRNORM: 有普通数据可写
            POLLWRBAND: 有紧急数据可写
            POLLERR: 有错误发生
            POLLHUP: 有描述符挂起事件发生
            POLLNVAL: 描述符非法
            */
            if (pfd.revents & POLLPRI)
            {
                lseek(pfd.fd, 0, SEEK_SET);
                num = read(pfd.fd, buf, 8);
                buf[num - 1] = '\0';
                ret = atoi(buf);
                for (int i = 0; i < 8; i++)
                    printf("huagao::buf[%d] = %d\n", i, buf[i]);
                printf("huagao::atoi(buf) ret = %d\n", ret);
            }
            key_value = CH455_Read();
            printf("CH455_Read() = %02x\n", key_value);
            printf("--------------------------------------------\n");
            printf("\n");
        }
        else if (ret == 0)
        {
            printf("--------------------------------------------\n");
            printf("huagao::ret = %d\n", ret);
            printf("huagao::poll time out.\n");
            printf("--------------------------------------------\n");
            printf("\n");
        }
        else
        {
            printf("--------------------------------------------\n");
            printf("huagao::ret = %d\n", ret);
            printf("huagao::poll err.\n");
            printf("--------------------------------------------\n");
            printf("\n");
        }
    }
}
int main(void)
{
    system("echo 52 > /sys/class/gpio/export");
    system("echo in > /sys/class/gpio/gpio52/direction");
    system("echo falling > /sys/class/gpio/gpio52/edge");
    key_Inter();
    return 0;
}