//#include <Wire.h>
#include "RTClib.h"
#include <Adafruit_NeoPixel.h>
#include <TinyGPS.h>

#define DISPLAY_PIN 4

RTC_DS1307 rtc;
Adafruit_NeoPixel *leds;
TinyGPS gps;

#define RED 0x00ff0000
#define BLUE 0x000000088
#define GREEN 0x00008800
#define WHITE 0x00ffffff

const uint8_t font[] = {
    0x1f, 0x11, 0x1f, // 0
    0x12, 0x1F, 0x10, // 1
    0x1D, 0x15, 0x17, // 2
    0x15, 0x15, 0x1f, // 3
    0x07, 0x04, 0x1F, // 4
    0x17, 0x15, 0x1D, // 5
    0x1F, 0x15, 0x1D, // 6
    0x01, 0x01, 0x1F, // 7
    0x1F, 0x15, 0x1F, // 8
    0x17, 0x15, 0x1F, // 9
    0x00, 0x0A, 0x00, // :
    0x00, 0x0A, 0x00, // ;
};

void draw(int x, int y, char *text, uint32_t color) {
    uint8_t pos = 0;
    for (unsigned int l = 0; l < strlen(text); l++) {
        uint8_t ch = text[l] - 0x30;
        for (uint8_t c = 0; c < 3 ; c++) {
            uint8_t colbits = font[ch * 3 + c];
            if (colbits != 0) {
                for (int r = 0; r < 5; r++) {
                    uint32_t col = ((colbits & (1 << r)) == 0) ? 0 : color;
                    uint32_t pixel = 32 * (y + r) + x + pos;
                    leds->setPixelColor(pixel, col);
                }
                pos += 1;
            }
        }
        if (l < strlen(text) - 1)
            pos += 1;
    }
}

bool isDST(DateTime now) {
    // from sunday before last friday of march
    // to last sunday of october
    DateTime d = DateTime(now.year(), 4, 1) - TimeSpan(1, 0, 0, 0);
    while (d.dayOfTheWeek() != 5)
        d = d - TimeSpan(1, 0, 0, 0);
    while (d.dayOfTheWeek() != 0)
        d = d - TimeSpan(1, 0, 0, 0);
    DateTime dststart = d;
    d = DateTime(now.year(), 11, 1) - TimeSpan(1, 0, 0, 0);
    while (d.dayOfTheWeek() != 1)
        d = d - TimeSpan(1, 0, 0, 0);
    DateTime dstend = d;
    if ((now == dststart && now.hour() >= 2) ||
        (now > dststart && now < dstend) ||
        (now == dstend && now.hour() < 2))
        return true;    
    return false;
}

void setup() {
    Serial.begin(9600);
    Serial.println("start");
    Serial2.begin(4800);
    leds = new Adafruit_NeoPixel(32 * 8, DISPLAY_PIN, NEO_GRB + NEO_KHZ800);
    leds->begin();
    leds->show();
    leds->clear();
    //leds->setBrightness(BRIGHTNESS);
    rtc.begin();
}

unsigned long gpsDate;
unsigned long gpsTime;

void loop() {
    while (Serial2.available()) {
        char c = Serial2.read();
        //delay(10);
        Serial.print(c);
        if (gps.encode(c)) {
            digitalWrite(LED_BUILTIN, HIGH);
            Serial.println("XXXXXX");
            unsigned long age;
            gps.get_datetime(&gpsDate, &gpsTime, &age);
            //Serial.print(gpsDate);
            //Serial.print(" ");
            //Serial.print(gpsTime);
            //Serial.print(" ");
            //Serial.println(age);
        }
    }

    DateTime now;
    // if not provisioned, check gps, time=0:0:0
    //if (rtc.isrunning())
    if (gpsDate && gpsTime) {
        int day = gpsDate / 10000;
        int month = (gpsDate / 100) % 100;
        int year = gpsDate % 100;
        int hour = gpsTime / 1000000;
        int minute = (gpsTime / 10000) % 100;
        int second = (gpsTime / 100) % 100;
        now = DateTime(year, month, day, hour, minute, second);
        rtc.adjust(now);
    } else
        now = DateTime();
    
    char buf[6];
    sprintf(buf, "%02d:%02d", now.hour(), now.minute());
    //Serial.println(buf);
    draw(2, 1, buf, 0xff0000);
    sprintf(buf, ";%02d", now.second());
    //Serial.println(buf);
    draw(21, 1, buf, 0x880000);
    leds->show();
    delay(10);
}