/*
 * btn.c
 *
 * handles buttons as well as the
 * DIP switches (in case action is desired by hot-switching)
 */


#include <ch32v20x.h>

#include "periph/btn.h"



struct Btn btn[BTN_COUNT] = {0};



void btn_init()
{
    uint8_t i;

    // this function assumes GPIO has been configured already

    // initialize default setup
    btn[BTN1]._pintype = BTN1_PIN;
    btn[BTN2]._pintype = BTN2_PIN;

    btn[DIP1]._pintype = DIP1_PIN;
    btn[DIP2]._pintype = DIP2_PIN;
    btn[DIP3]._pintype = DIP3_PIN;

    for (i = 0; i < BTN_COUNT; i++) {
        btn[i]._mask = BTN_RELEASE;

        // ignore any currently pressed buttons
        if (!(BTN_PORT->INDR & (1 << (btn[i]._pintype & BTN_PIN_MASK)))) {
            btn[0]._mask |= BTN_IGNORE;
        }
    }
}

void btn_poll()
{
    uint8_t i;
    uint8_t ignore;

    uint8_t pushed;

    for (i = 0; i < BTN_COUNT; i++) {
        ignore = btn[i]._mask & BTN_IGNORE;

        // active low type buttons
        pushed = BTN_PORT->INDR & (1 << (btn[i]._pintype & BTN_PIN_MASK)) ? 0 : 1;

        if (pushed) {
            // hold counter
            if (btn[i]._count < 0xffff) btn[i]._count++;

            // pushed long enough?
            if (btn[i]._count < BTN_DEBOUNCE) continue;

            // first push?
            if (!(btn[i]._mask & BTN_PUSH)) {
                btn[i]._mask = BTN_PUSH | ignore;
                if (btn[i].cb_push && !ignore) {
                    btn[i].cb_push(i);
                    btn[i]._mask |= (BTN_PUSH << 4);
                }
            } else if (btn[i]._count >= btn[i].hold) {
                // held to count limit

                // if button is not repeatable, do not retrigger
                if ((btn[i]._mask & BTN_HOLD) && !btn[i].repeat) continue;

                btn[i]._mask |= BTN_HOLD;
                // call callback only if not in ignore state
                if (btn[i].cb_hold && !ignore) {
                    btn[i].cb_hold(i);
                    btn[i]._mask |= (BTN_HOLD << 4);
                }

                // apply repeat rate to count
                if (btn[i].repeat > btn[i]._count) {
                    btn[i]._count = 0;
                } else btn[i]._count -= btn[i].repeat;
            }
        } else {
            // is not pushed
            if (!(btn[i]._mask & BTN_RELEASE)) {
                // note: release will remove ignore status
                btn[i]._mask = BTN_RELEASE;
                btn[i]._count = 0;
                // call callback only if not in ignore state
                if (btn[i].cb_release && !ignore) {
                    btn[i].cb_release(i);
                    btn[i]._mask |= (BTN_RELEASE << 4);
                }
            }
        }
    }
}