#include <stdio.h>
#include <stdbool.h>
#include "automat.h"

typedef enum {A=0, B, C, D, E, F, NR_OF_STATES} state_t;

static state_t s_curstate = A;
static int s_guthaben = 0;
static bool s_kaffee_los = false;
static bool s_muenz_rueck = false;
static bool s_display = false;
static const char* s_display_string = "Warten";

void automat_reset(void)
{
    s_curstate = A;
    s_guthaben = 0;
    s_kaffee_los = false;
    s_muenz_rueck = false;
    s_display = false;
    s_display_string = "Warten";
}

void automat_transition(BOOL becher, BOOL muenze, BOOL muenz_wert)
{
    s_kaffee_los = false;
    s_muenz_rueck = false;
    s_display = false;

    int wert = muenz_wert ? 2 : 1;

    switch (s_curstate) {
        case A: case B: case C: case D: case E:
            // Münzeinwurf
            if (muenze) {
                if (s_guthaben + wert > 4) {
                    s_muenz_rueck = true;
                    s_display = true;
                    s_display_string = "Zu viel! Münze zurück";
                    break;
                } else {
                    s_guthaben += wert;
                }
            }

            // Guthaben prüfen
            if (s_guthaben < 4) {
                if      (s_guthaben == 0) { s_curstate = A; s_display_string = "Warten"; }
                else if (s_guthaben == 1) { s_curstate = B; s_display_string = "1 Euro"; }
                else if (s_guthaben == 2) { s_curstate = C; s_display_string = "2 Euro"; }
                else if (s_guthaben == 3) { s_curstate = D; s_display_string = "3 Euro"; }
                // Kein Display aktivieren!
            } else if (s_guthaben == 4) {
                if (becher) {
                    s_curstate = F;
                    s_kaffee_los = true;
                    s_display = true;
                    s_display_string = "Kaffee wird ausgegeben";
                    s_guthaben = 0;
                } else {
                    s_curstate = E;
                    s_display = true;
                    s_display_string = "Bitte Becher unterstellen!";
                }
            }
            break;

        case F:
            s_display = true;
            s_display_string = "Becher entnehmen";
            if (!becher) {
                s_curstate = A;
                s_display = false;
                s_display_string = "Warten";
            }
            break;

        default:
            s_curstate = A;
            s_guthaben = 0;
            s_display = false;
            s_display_string = "Warten";
            break;
    }
}

fsm_action_t automat_output(void)
{
    return (fsm_action_t){
        .display = s_display,
        .muenz_rueck = s_muenz_rueck,
        .kaffee_los = s_kaffee_los,
        .guthaben = s_guthaben,
        .display_string = s_display_string
    };
}

//gcc automat.c view.c main.c io.c checker.c -o console_automat