// vim: tabstop=4 shiftwidth=4 noexpandtab


#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>

#include "ws2812.h"


#define LED_ARRAY_LENGTH 64  // ws2812 array is 64 LEDs long (adapt it to your needs)

// pin B13 is connected to DIN of ws2812 array:
#define LED_ARRAY_PORT GPIOB
#define LED_ARRAY_PIN GPIO13
#define RCC_GPIO_PORT RCC_GPIOB

#define MAX_BRIGHTNESS 10  // maximum brightness per LED (value from 0 to 255)


void clock_init(void);
void gpio_init(void);
void delay_ms(uint16_t delay);
void animation_full_color(WS2812_ARRAY *leds);


int main(void)
{
	WS2812_ARRAY leds;  // ws2812 control struct
	uint8_t led_buffer[LED_ARRAY_LENGTH*3];  // reserve a uint8_t for each color in each LED

	clock_init();
	gpio_init();
	ws2812_init(&leds, LED_ARRAY_PORT, LED_ARRAY_PIN, (uint8_t *)led_buffer, LED_ARRAY_LENGTH);

	while(1)
	{
		animation_full_color(&leds);
	}

	return 0;
}


void clock_init(void)
{
	rcc_clock_setup_in_hse_8mhz_out_72mhz();  // use external oscillator for 72 MHz sysclock frequency
	rcc_periph_clock_enable(RCC_GPIO_PORT);  // enable gpio port clock to use LED_ARRAY_PORT
}


void gpio_init(void)
{
	gpio_set_mode(LED_ARRAY_PORT, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, LED_ARRAY_PIN);  // settings for LED_ARRAY_PIN
	gpio_clear(LED_ARRAY_PORT, LED_ARRAY_PIN);  // set LED_ARRAY_PIN to 0 V
}


void delay_ms(uint16_t delay)
{
	uint32_t delay_nops = delay * 4500;  // just @ 72 MHz!
	for (uint32_t i = 0; i < delay_nops; i++) {
		__asm__("nop");
	}
}


void animation_full_color(WS2812_ARRAY *leds)
{
	// set red
	ws2812_clear_buffer(leds);
	for (uint32_t i = 0; i < leds->array_length*3; i++)
	{
		if (i%3 == 0) leds->array_buffer[i] = MAX_BRIGHTNESS;
	}
	ws2812_write_buffer_to_leds(leds);
	delay_ms(500);

	// set green
	ws2812_clear_buffer(leds);
	for (uint32_t i = 0; i < leds->array_length*3; i++)
	{
		if (i%3 == 1) leds->array_buffer[i] = MAX_BRIGHTNESS;
	}
	ws2812_write_buffer_to_leds(leds);
	delay_ms(500);

	// set blue
	ws2812_clear_buffer(leds);
	for (uint32_t i = 0; i < leds->array_length*3; i++)
	{
		if (i%3 == 2) leds->array_buffer[i] = MAX_BRIGHTNESS;
	}
	ws2812_write_buffer_to_leds(leds);
	delay_ms(500);

	// set white
	ws2812_clear_buffer(leds);
	for (uint32_t i = 0; i < leds->array_length*3; i++)
	{
		leds->array_buffer[i] = MAX_BRIGHTNESS;
	}
	ws2812_write_buffer_to_leds(leds);
	delay_ms(500);

	// set off
	ws2812_clear_buffer(leds);
	ws2812_write_buffer_to_leds(leds);
	delay_ms(500);
}