#include "ch32fun.h"
#include "i2c_driver.h"
#include "fan_driver.h"
#include "i2c.h"

volatile uint8_t i2c_registers[16] = {0x00};

void update_fan_from_regs(volatile uint8_t *reg) {
    fan_driver_target_rpm = i2c_get_register_word(reg, I2C_REG_TARGET_RPM);
    fan_driver_pwm_set_duty(i2c_get_register_word(reg, I2C_REG_CURRENT_DUTY));
    fan_driver_constant_duty = !(reg[I2C_REG_MODE] & 0x01);
    fan_driver_powered_down = (reg[I2C_REG_MODE] & 0x02) >> 1;
}

void onWrite(const uint8_t reg, const uint8_t length) {
    if (length == 0) return;

    switch (reg) {
        case I2C_REG_TARGET_RPM:
            update_fan_from_regs(i2c_registers);
            printf("set tgt fan speed to %d\n", fan_driver_target_rpm);
            break;

        case I2C_REG_CURRENT_DUTY:
            update_fan_from_regs(i2c_registers);
            printf("set duty cycle to %d\n", fan_driver_pwm_get_duty());
            break;

        case I2C_REG_MODE:
            update_fan_from_regs(i2c_registers);
            printf("set mode register to %x. constant duty mode is %d, powered down is %d\n",
                   i2c_registers[I2C_REG_MODE], fan_driver_constant_duty, fan_driver_powered_down);
            break;

        default:
            i2c_registers_reinit(i2c_registers);
            break;
    }
}

int main() {
    SystemInit();
    printf("System bootup\n");

    // Initialize I2C slave
    funGpioInitC();
    funPinMode(PC1, GPIO_CFGLR_OUT_10Mhz_AF_OD); // SDA
    funPinMode(PC2, GPIO_CFGLR_OUT_10Mhz_AF_OD); // SCL
    i2c_registers_reinit(i2c_registers);
    i2c_registers_set_defaults(i2c_registers);
    update_fan_from_regs(i2c_registers);
    fan_driver_init();

    SetupI2CSlave(I2C_DEVICE_ADDR, i2c_registers, sizeof(i2c_registers), onWrite, NULL, false);

    while (1) {
        fan_driver_control_loop();

        i2c_set_register_word(i2c_registers, I2C_REG_CURRENT_RPM, fan_driver_current_rpm);
        i2c_set_register_word(i2c_registers, I2C_REG_CURRENT_DUTY, fan_driver_pwm_get_duty());
        i2c_registers[I2C_REG_STATE] = (!fan_driver_is_steady) | (fan_driver_is_stalled << 1);

        Delay_Ms(250);
    }
}