#include <debounce.h>

void Debounce_Init(Debounce_t* self){
    self->state = kButtonState_IDLE;
    self->debounce_cnt = 0;
    self->long_press_cnt = 0;
    self->double_click_cnt = 0;
    self->is_pressed = 0;
    self->last_pressed = 0;
}


ButtonEvent_t Debounce_Handle(Debounce_t* self, uint8_t cur_state){
    ButtonEvent_t event = kButtonEvent_NONE;
    self->is_pressed = cur_state;
    switch (self->state) {
        case kButtonState_IDLE:{
            if(cur_state == 1){
                self->state = kButtonState_DEBOUNCE;
                self->debounce_cnt = 0;
            }
            break;
        }
        case kButtonState_DEBOUNCE:{
            if(cur_state==1){
                self->debounce_cnt++;
                if(self->debounce_cnt >= DEBOUNCE_TICKS){
                    self->state = kButtonState_PRESS;
                    self->debounce_cnt = 0;
                    event = kButtonEvent_PRESS; /* 触发下按事件 */
                }
            }else{
                self->state = kButtonState_IDLE;
            }
            break;
        }
        case kButtonState_PRESS:{
            if(cur_state==1){
                self->long_press_cnt++;
                if(self->long_press_cnt >= DEBOUNCE_LONG_TICKS){
                    self->state = kButtonState_LONG_PRESS;
                    event = kButtonEvent_LONG_PRESS;
                }
            }else{
                // 第一击释放，进入释放消抖，防止触摸屏抖动误判
                self->state = kButtonState_RELEASE_DEBOUNCE;
                self->debounce_cnt = 0;
                self->long_press_cnt = 0;
            }
            break;
        }
        case kButtonState_LONG_PRESS:{
            if(cur_state==0){
                self->state = kButtonState_IDLE;
                self->long_press_cnt = 0;
                event = kButtonEvent_RELEASE;
            }
            break;
        }
        case kButtonState_WAIT_DOUBLE:{
            if(cur_state==1){ /* 在规定时间内再次按下，判定为双击 */
                self->state = kButtonState_DOUBLE_DEBOUNCE; /* 去除第二次抖动 */
                self->debounce_cnt = 0;
            }else{
                self->double_click_cnt++;
                if(self->double_click_cnt>=DEBOUNCE_DOUBLE_TICKS){ // 超时未按下，判定为普通的独立单击
                    self->state = kButtonState_LONG_PRESS;
                    event = kButtonEvent_CLICK;
                    self->double_click_cnt = 0;
                }
            }
            break;
        }
        case kButtonState_DOUBLE_DEBOUNCE:{
            if(cur_state==1){
                self->debounce_cnt++;
                if(self->debounce_cnt >= DEBOUNCE_TICKS){
                    self->state = kButtonState_LONG_PRESS;  /* 等待释放 */
                    self->debounce_cnt = 0;
                    event = kButtonEvent_DOUBLE_CLICK;      /* 确认双击 */
                }
            }else{
                self->state = kButtonState_IDLE;
            }
            break;
        }
        case kButtonState_RELEASE_DEBOUNCE:{
            if(cur_state==0){
                self->debounce_cnt++;
                if(self->debounce_cnt >= DEBOUNCE_TICKS){
                    // 确认释放，开始计时等待第二击
                    self->state = kButtonState_WAIT_DOUBLE;
                    self->double_click_cnt = 0;
                }
            }else{
                self->state = kButtonState_PRESS; // 抖动,返回按下状态
            }
            break;
        }
        default: break;
    }

    self->last_pressed = cur_state;

    return event;
}