#include "pages_pwm.h"
#include "dzbj_gpio.h"
#include "driver/ledc.h"

// 当前亮度值（用于休眠恢复）
static uint8_t current_brightness = 50;

// 获取当前亮度值
uint8_t pwm_get_brightness(void) {
    return current_brightness;
}

// 设置屏幕亮度，percent范围0-100
// 0=完全关闭背光，10~100为正常亮度范围
// 显示10%~100%映射到实际亮度20%~100%，背光低电平有效需反转占空比
void pwm_set_brightness(uint8_t percent) {
    if (percent == 0) {
        // 完全关闭背光（低电平有效，占空比100%=全高=关闭）
        ledc_set_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, 8191);
        ledc_update_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0);
        return;
    }
    if (percent < 10) percent = 10;
    if (percent > 100) percent = 100;
    current_brightness = percent;
    uint32_t actual = 20 + (uint32_t)(percent - 10) * 80 / 90;
    uint32_t duty = 8191 - (8191 * actual) / 100;
    ledc_set_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0, duty);
    ledc_update_duty(LEDC_LOW_SPEED_MODE, LEDC_CHANNEL_0);
}

// 初始化PWM背光
void pwm_init(void) {
    ledc_timer_config_t ledc_timer = {
        .speed_mode       = LEDC_LOW_SPEED_MODE,
        .timer_num        = LEDC_TIMER_0,
        .duty_resolution  = LEDC_TIMER_13_BIT,
        .freq_hz          = 5000,
        .clk_cfg          = LEDC_AUTO_CLK
    };
    ledc_timer_config(&ledc_timer);
    ledc_channel_config_t ledc_channel = {
        .speed_mode     = LEDC_LOW_SPEED_MODE,
        .channel        = LEDC_CHANNEL_0,
        .timer_sel      = LEDC_TIMER_0,
        .intr_type      = LEDC_INTR_DISABLE,
        .gpio_num       = PIN_LCD_EN,
        .duty           = 0,
        .hpoint         = 0
    };
    ledc_channel_config(&ledc_channel);
    pwm_set_brightness(50);  // 初始亮度50%
}