#include <stdlib.h>
#include <string.h>
#include "totp_face.h"
#include "watch.h"
#include "watch_utility.h"
#include "TOTP.h"

// Use https://cryptii.com/pipes/base32-to-hex to convert base32 to hex
// Use https://totp.danhersam.com/ to generate test codes for verification

static const uint8_t num_keys = 2;
static uint8_t keys[] = {
    0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x21, 0xde, 0xad, 0xbe, 0xef, // 1 - JBSWY3DPEHPK3PXP
    0x5c, 0x0d, 0x27, 0x6b, 0x6d, 0x9a, 0x01, 0x22, 0x20, 0x4f  // 2 - E9M348K0ADIDFBC2
};
static const uint8_t key_sizes[] = {
    10,
    10
};
static const uint32_t timesteps[] = {
    30,
    30
};
static const char labels[][2] = {
    { 'a', 'b' },
    { 'c', 'd' }
};

void totp_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
    (void) settings;
    (void) watch_face_index;
    if (*context_ptr == NULL) *context_ptr = malloc(sizeof(totp_state_t));
}

void totp_face_activate(movement_settings_t *settings, void *context) {
    (void) settings;
    memset(context, 0, sizeof(totp_state_t));
    totp_state_t *totp_state = (totp_state_t *)context;
    TOTP(keys, key_sizes[0], timesteps[0]);
    totp_state->timestamp = watch_utility_date_time_to_unix_time(watch_rtc_get_date_time(), movement_timezone_offsets[settings->bit.time_zone] * 60);
    totp_state->current_code = getCodeFromTimestamp(totp_state->timestamp);
}

bool totp_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
    (void) settings;

    totp_state_t *totp_state = (totp_state_t *)context;
    char buf[14];
    uint8_t valid_for;
    div_t result;
    uint8_t index = totp_state->current_index;

    switch (event.event_type) {
        case EVENT_TICK:
            totp_state->timestamp++;
            // fall through
        case EVENT_ACTIVATE:
            result = div(totp_state->timestamp, timesteps[index]);
            if (result.quot != totp_state->steps) {
                totp_state->current_code = getCodeFromTimestamp(totp_state->timestamp);
                totp_state->steps = result.quot;
            }
            valid_for = timesteps[index] - result.rem;
            sprintf(buf, "%c%c%2d%06lu", labels[index][0], labels[index][1], valid_for, totp_state->current_code);

            watch_display_string(buf, 0);
            break;
        case EVENT_MODE_BUTTON_UP:
            movement_move_to_next_face();
            break;
        case EVENT_LIGHT_BUTTON_DOWN:
            movement_illuminate_led();
            break;
        case EVENT_TIMEOUT:
            movement_move_to_face(0);
            break;
        case EVENT_ALARM_BUTTON_UP:
            if (index + 1 < num_keys) {
                totp_state->current_key_offset += key_sizes[index];
                totp_state->current_index++;
            } else {
                // wrap around to first key
                totp_state->current_key_offset = 0;
                totp_state->current_index = 0;
            }
            TOTP(keys + totp_state->current_key_offset, key_sizes[totp_state->current_index], timesteps[totp_state->current_index]);
            break;
        case EVENT_ALARM_BUTTON_DOWN:
        case EVENT_ALARM_LONG_PRESS:
        default:
            break;
    }

    return true;
}

void totp_face_resign(movement_settings_t *settings, void *context) {
    (void) settings;
    (void) context;
}