#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>

#ifdef ENABLE_OLED
# include "i2c_master.h"
#endif

// Port A0 - A3	-> LED Data
// Port A5 		-> Select Output
// Port A4, A6	-> I2C Display
// Port A7		-> Enable Output
// Port B2 		-> Button Input (Pulled-Up)

// Button Press Times
#define BTN_LONG_PRESS_MS 1000
#define BTN_DEBOUNCE_MS     50

// Size of each strip
#define LED0_COUNT 12
#define LED1_COUNT 12
#define LED2_COUNT 12
#define LED3_COUNT 15

// ms per frame
#define LED0_MS 500
#define LED1_MS 500
#define LED2_MS 500
#define LED3_MS 400

// ms offset
#define LED0_MS_OFFSET 0
#define LED1_MS_OFFSET 0
#define LED2_MS_OFFSET 0
#define LED3_MS_OFFSET 0

#define LED0_PORT PORTA
#define LED1_PORT PORTA
#define LED2_PORT PORTA
#define LED3_PORT PORTA

#define LED0_BIT 0
#define LED1_BIT 1
#define LED2_BIT 2
#define LED3_BIT 3

// NeoPixel Defines
#define T1H  900    // Width of a 1 bit in ns
#define T1L  600    // Width of a 1 bit in ns
#define T0H  400    // Width of a 0 bit in ns
#define T0L  900    // Width of a 0 bit in ns
#define RES 6000
#define RES_HALF RES / 2
#define NS_PER_SEC (1000000000L)
#define CYCLES_PER_SEC (F_CPU)
#define NS_PER_CYCLE ( NS_PER_SEC / CYCLES_PER_SEC )
#define NS_TO_CYCLES(n) ( (n) / NS_PER_CYCLE )

// ms counter
uint64_t ms = 0;

// Led update times
uint64_t led_ms_update[4] = {LED0_MS_OFFSET, LED1_MS_OFFSET, LED2_MS_OFFSET,
	LED3_MS_OFFSET};

#ifdef ENABLE_OLED
// I2C Display Address
uint8_t display_address = 0x78;

// Draw only changed digits
uint8_t old_time[7] = {0, 0, 0, 0, 0, 0, 0};

uint64_t old_time_ms = 0;
#endif

// ms Counter Func
ISR(TIM1_CAPT_vect)
{
	ms += 10;
}

// NeoPixel Funcs
static inline void send_bit_led0(uint8_t bitVal);
static inline void send_bit_led1(uint8_t bitVal);
static inline void send_bit_led2(uint8_t bitVal);
static inline void send_bit_led3(uint8_t bitVal);
static inline void send_byte(uint8_t byte, uint8_t led);
static inline void send_pixel(uint8_t r, uint8_t g, uint8_t b, uint8_t led);
void show_leds();

// Hardware Init
void init();

// Function to switch states
void state_switch(uint8_t is_onoff);

#ifdef ENABLE_OLED
// I2C Display Funcs
void init_display();
void send_command(uint8_t cmd);
void set_display_coords(uint8_t x_start, uint8_t x_end, uint8_t y_start, uint8_t y_end);
void show_time(uint64_t ms);
void draw_dots(uint8_t pos);
void draw_digit(uint8_t pos, uint8_t digit);
#endif

// Call function to show a frame and prepare idx for next frame
void sun_and_moon(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led);
void clock_no_bg(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led);
void loading(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led);
void off(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led);

void (*func_list[4])(uint8_t, uint8_t*, uint8_t, uint8_t) =
{
	sun_and_moon, clock_no_bg, loading, off
};

void (*send_ptr[4])(uint8_t) =
{
	send_bit_led0, send_bit_led1, send_bit_led2, send_bit_led3
};

enum states
{
	STATE_SUN_MOON = 0,
	STATE_CLOCK_NO1,
	STATE_CLOCK_NO2,
	STATE_LOADING,
	STATE_PC
};

uint8_t led0_idx = 0;
uint8_t led1_idx = 0;
uint8_t led2_idx = 0;
uint8_t led3_idx = 0;
uint8_t colour = 0;
uint8_t func_idx = 0;
uint8_t backup_func_idx = sizeof(func_list) / sizeof(func_list[0]) - 1;
uint8_t btn_old_state = 0;
uint8_t colour_state = STATE_SUN_MOON;
uint8_t current_state;
uint64_t btn_down = -1;

int main()
{
	uint8_t show;

	init();
// Main loop
while(1)
{
	show = 0;

	if (ms >= led_ms_update[0])
	{
		led_ms_update[0] += LED0_MS;
		func_list[func_idx](LED0_COUNT, &led0_idx, colour, 0);
		show = 1;
	}

	if (ms >= led_ms_update[1])
	{
		led_ms_update[1] += LED1_MS;
		func_list[func_idx](LED1_COUNT, &led1_idx, colour, 1);
		show = 1;
	}

	if (ms >= led_ms_update[2])
	{
		led_ms_update[2] += LED2_MS;
		func_list[func_idx](LED2_COUNT, &led2_idx, colour, 2);
		show = 1;
	}

	if (ms >= led_ms_update[3])
	{
		led_ms_update[3] += LED3_MS;
		func_list[func_idx](LED3_COUNT, &led3_idx, colour, 3);
		show = 1;
	}

	if (show)
	{
		show_leds();
	}

#ifdef ENABLE_OLED
	if (ms - 1000 >= old_time_ms)
	{
		show_time(ms);
		old_time_ms = ms;
	}
#endif

	// Button Press
	current_state = PINB & 0x04;
	if (btn_old_state && !current_state)
	{
		btn_down = ms;
	}

	// Button Unpress
	if (!btn_old_state && current_state)
	{
		if (ms - BTN_DEBOUNCE_MS >= btn_down)
		{
			btn_down = -1;
			state_switch(0);
		}
	}
	btn_old_state = current_state;

	// Long Press Time Has Passed
	if (ms - BTN_LONG_PRESS_MS >= btn_down)
	{
		btn_down = -1;
		state_switch(1);
	}
}
}

inline void send_bit_led0(uint8_t value)
{
    if (value)
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED0_PORT)),
			[bit]		"I" (LED0_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T1H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T1L) - 2)
		);
    }
    else
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED0_PORT)),
			[bit]		"I" (LED0_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T0H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T0L) - 2)
		);
    }
}

inline void send_bit_led1(uint8_t value)
{
    if (value)
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED1_PORT)),
			[bit]		"I" (LED1_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T1H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T1L) - 2)
		);
    }
    else
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED1_PORT)),
			[bit]		"I" (LED1_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T0H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T0L) - 2)
		);
    }
}

inline void send_bit_led2(uint8_t value)
{
    if (value)
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED2_PORT)),
			[bit]		"I" (LED2_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T1H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T1L) - 2)
		);
    }
    else
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED2_PORT)),
			[bit]		"I" (LED2_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T0H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T0L) - 2)
		);
    }
}

inline void send_bit_led3(uint8_t value)
{
    if (value)
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED3_PORT)),
			[bit]		"I" (LED3_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T1H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T1L) - 2)
		);
    }
    else
    {
		asm volatile
		(
			"sbi %[port], %[bit] \n\t"
			".rept %[onCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			"cbi %[port], %[bit] \n\t"
			".rept %[offCycles] \n\t"
			"nop \n\t"
			".endr \n\t"
			::
			[port]		"I" (_SFR_IO_ADDR(LED3_PORT)),
			[bit]		"I" (LED3_BIT),
			[onCycles]	"I" (NS_TO_CYCLES(T0H) - 2),
			[offCycles]	"I" (NS_TO_CYCLES(T0L) - 2)
		);
    }
}

inline void send_byte(uint8_t byte, uint8_t led)
{
	uint8_t i;

	for (i = 0; i < 8; i++)
	{
		send_ptr[led](byte & 0xF0);
		byte <<= 1;
	}
}

inline void send_pixel(uint8_t r, uint8_t g, uint8_t b, uint8_t led)
{
	cli();
	send_byte(g, led);
	send_byte(r, led);
	send_byte(b, led);
	sei();
}

void show_leds()
{
	asm volatile
	(
		".rept %[resCycles] \n\t"
		"nop \n\t"
		".endr \n\t"
		".rept %[resCycles] \n\t"
		"nop \n\t"
		".endr \n\t"
		::
		[resCycles]		"I" (NS_TO_CYCLES(RES_HALF) - 2)
	);
}

void init()
{
	DDRA = (1 << 0) | (1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 7);
	PORTB = (1 << 2);

#ifdef ENABLE_OLED
	init_display();
#endif

	// TIM1 init - CTC - prescaler 8 - 10ms interrupt
	TCCR1B = (1 << WGM13) | (1 << WGM12) | (1 << CS11);
	ICR1 = (F_CPU / 8 / 100) - 1;
	TIMSK1 = (1 << ICIE1);
	sei();
}

void state_switch(uint8_t is_onoff)
{
	uint8_t tmp_func_idx;

	if (is_onoff == 0)
	{
		// If we're off don't change anything
		if (func_idx == sizeof(func_list) / sizeof(func_list[0]) - 1)
		{
			return;
		}

		switch (colour_state)
		{
		case STATE_SUN_MOON:
			func_idx = 1;
			colour_state = STATE_CLOCK_NO1;
			colour = 0;
			break;

		case STATE_CLOCK_NO1:
			colour_state = STATE_CLOCK_NO2;
			colour = 1;
			break;

		case STATE_CLOCK_NO2:
			func_idx = 2;
			colour_state = STATE_LOADING;
			colour = 0;
			break;

		case STATE_LOADING:
			func_idx = 0;
			PORTA ^= 0x20;
			colour_state = STATE_PC;
			break;

		case STATE_PC:
			PORTA ^= 0x20;
			colour_state = STATE_SUN_MOON;
			break;
		}
	}
	else
	{
		tmp_func_idx = backup_func_idx;
		backup_func_idx = func_idx;
		func_idx = tmp_func_idx;
	}
	led0_idx = 0;
	led1_idx = 0;
	led2_idx = 0;
	led3_idx = 0;
}

void sun_and_moon(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led)
{
	uint8_t i;
	uint8_t colour1[3] = {0xFF, 0x80, 0x00};
	uint8_t colour2[3] = {0x00, 0x80, 0xFF};
	uint8_t min;
	uint8_t max;
	
	if (*idx <= count / 2)
	{
		min = *idx;
		max = *idx + count / 2;

		for (i = 0; i < min; ++i)
		{
			send_pixel(colour1[0], colour1[1], colour1[2], led);
		}
		for (i = min; i < max; ++i)
		{
			send_pixel(colour2[0], colour2[1], colour2[2], led);
		}
		for (i = max; i < count; ++i)
		{
			send_pixel(colour1[0], colour1[1], colour1[2], led);
		}
	}
	else
	{
		min = *idx - count / 2;
		max = *idx;

		for (i = 0; i < min; ++i)
		{
			send_pixel(colour2[0], colour2[1], colour2[2], led);
		}
		for (i = min; i < max; ++i)
		{
			send_pixel(colour1[0], colour1[1], colour1[2], led);
		}
		for (i = max; i < count; ++i)
		{
			send_pixel(colour2[0], colour2[1], colour2[2], led);
		}
	}
	(*idx)++;
	(*idx) %= count;
}

void clock_no_bg(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led)
{
	uint8_t i;
	uint8_t colour1[3] = {0xFF, 0x80, 0x00};
	uint8_t colour2[3] = {0x00, 0x80, 0xFF};
	uint8_t black[3] = {0x00, 0x00, 0x00};
	uint8_t* main_colour;

	if (0 == colour)
	{
		main_colour = colour1;
	}
	else
	{
		main_colour = colour2;
	}

	for (i = 0; i < count; ++i)
	{
		if (i == *idx)
		{
			send_pixel(main_colour[0], main_colour[1], main_colour[2], led);
		}
		else
		{
			send_pixel(black[0], black[1], black[2], led);
		}
	}

	(*idx)++;
	(*idx) %= count;
}

void loading(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led)
{
	uint8_t i;
	uint8_t colour1[3] = {0xFF, 0x80, 0x00};
	uint8_t colour2[3] = {0x00, 0x80, 0xFF};

	if (*idx < count)
	{
		for (i = 0; i < count; ++i)
		{
			if (i <= *idx)
			{
				send_pixel(colour1[0], colour1[1], colour1[2], led);
			}
			else
			{
				send_pixel(colour2[0], colour2[1], colour2[2], led);
			}
		}
	}
	else
	{
		for (i = 0; i < count; ++i)
		{
			if (i <= *idx - count)
			{
				send_pixel(colour2[0], colour2[1], colour2[2], led);
			}
			else
			{
				send_pixel(colour1[0], colour1[1], colour1[2], led);
			}
		}
	}

	(*idx)++;
	(*idx) %= count * 2;
}

void off(uint8_t count, uint8_t* idx, uint8_t colour, uint8_t led)
{
	uint8_t black[3] = {0x00, 0x00, 0x00};

	for (uint8_t i = 0; i < count; ++i)
	{
		send_pixel(black[0], black[1], black[2], led);
	}
}

#ifdef ENABLE_OLED
void init_display()
{
	uint16_t i = 0;
	uint8_t cmdInit[] =
	{
		0xAE, 0xD5, 0x80, 0xA8,
		0x1F, 0xD3, 0x00, 0x40,
		0x8D, 0x14, 0x20, 0x00,
		0xA1, 0xC8, 0xDA, 0x02,
		0x81, 0x8F, 0xD9, 0xF1,
		0xDB, 0x40, 0xA4, 0xA6,
		0x2E, 0xAF
	};

	i2c_init();
    for (i = 0; i < sizeof(cmdInit); ++i)
    {
        send_command(cmdInit[i]);
    }

    set_display_coords(0x00, 0x7F, 0x00, 0x03);
    
    for(i = 0; i < 128*4; ++i)
    {
		i2c_write(0x00);
	}
	i2c_stop();
}

void send_command(uint8_t cmd)
{
    i2c_start(display_address);
    i2c_write(0x00);
    i2c_write(cmd);
    i2c_stop();
}

void set_display_coords(uint8_t x_start, uint8_t x_end, uint8_t y_start, uint8_t y_end)
{
	send_command(0x21);
	send_command(x_start);
	send_command(x_end);
	
	send_command(0x22);
	send_command(y_start);
	send_command(y_end);
	
	i2c_start(display_address);
	i2c_write(0x40);
}

void show_time(uint64_t ms)
{
	uint8_t new_time[7] = {0, 0, 0, 0, 0, 0, 0};
	uint8_t i;

	ms /= 1000;
	new_time[6] = ms % 10;
	ms /= 10;
	new_time[5] = ms % 6;
	ms /= 6;
	new_time[4] = ms % 10;
	ms /= 10;
	new_time[3] = ms % 6;
	ms /= 6;
	new_time[2] = ms % 10;
	ms /= 10;
	new_time[1] = ms % 10;
	ms /= 10;
	new_time[0] = ms % 10;

	for (i = 0; i < 7; ++i)
	{
		if (old_time[i] != new_time[i])
		{
			if (((2 == i) || (4 == i)) && (0 == old_time[i]))
			{
				draw_dots(i);
			}

			draw_digit(i, new_time[i]);
		}
		old_time[i] = new_time[i];
	}
}

void draw_dots(uint8_t pos)
{
	// Between hours and minutes
	if (2 == pos)
	{
		set_display_coords(50, 53, 1, 2);
	}

	// Between minutes and seconds
	if (4 == pos)
	{
		set_display_coords(90, 93, 1, 2);
	}

	i2c_write(0x0F);
	i2c_write(0x0F);
	i2c_write(0x0F);
	i2c_write(0x0F);
	i2c_write(0xF0);
	i2c_write(0xF0);
	i2c_write(0xF0);
	i2c_write(0xF0);
	i2c_stop();
}

void draw_digit(uint8_t pos, uint8_t digit)
{
	uint8_t i, j;
	uint8_t x_start;
	uint8_t x_end;
	uint8_t row[12];
	
	x_start = pos * 16;

	if (pos > 2)
	{
		x_start += 8;
	}

	if (pos > 4)
	{
		x_start += 8;
	}

	x_end = x_start + 15;
	set_display_coords(x_start + 2, x_end - 2, 0, 3);

	row[0] = 0xF0;
	row[1] = 0x00;
	row[2] = 0x00;
	row[3] = 0x03;
	row[4] = 0x00;
	row[5] = 0x00;
	row[6] = 0xC0;
	row[7] = 0xC0;
	row[8] = 0xC0;
	row[9] = 0x0F;
	row[10] = 0x03;
	row[11] = 0x0F;

	if (digit > 1)
	{
		row[1] = 0xF0;
	}

	if (digit > 2)
	{
		row[2] = 0xF0;
	}

	for (i = 3; i < 8; ++i)
	{
		if (digit > i)
		{
			row[i] = 0xFF;
		}
	}

	if (0 == digit)
	{
		row[2] = 0xF0;
		row[3] = 0xFF;
		row[5] = 0xFF;
		row[6] = 0xFF;
		row[8] = 0xFF;
	}

	for (i = 0; i < 12 * 4; ++i)
	{
		i2c_write(row[i / 4]);
	}

	i2c_stop();
}

#endif