#include <math.h>

#include <kernel/x86/pit.h>
#include <kernel/x86/io.h>

struct pit_state pit;

uint32_t normalize_divisor(uint32_t divisor)
{
	if (divisor == 0)
		return 65536;
	return clamp_u32(divisor, 0, 65535);
}

double get_time_from_divisor(uint32_t divisor)
{
	uint32_t _divisor = normalize_divisor(divisor);
		
	double clock_rate = 3579545.0 / 3.0; // This is for a bit more precision in the hz rate
	
	return (_divisor / (clock_rate)) * 1000;
}

/**
 * Im worried about an overflow
 *
 *
 * What i want to do is
 *
 * Every time we get the Timer intterupt, i want to increment a variable, just the amount of times its fired
 * and then we can use the time rate above to get total time elapsed, which we can use for sleep and stuff
 *
 * Im worried about overflows, but i can add something that will automatically flip it over? or do uints already roll over? they already rollover!!! WOOOO!!! 
 * just need to be aware that only a maximum of 52ms * 32int max (64 int max) can be tracked before it rolls over!
 */


uint16_t read_pit_count(uint8_t channel) // Only in lobyte/hibyte mode

{
	uint16_t count = 0;

	__asm__ volatile ("cli");


	outb(PIT_CMD_REG, (channel << 6)); // xx000000 where x is the channel

	count = inb(channel);
	count |= inb(channel) << 8;

	return count; // TODO make sure to enable interrupts after this
}

void set_pit_count(uint8_t channel, uint16_t count) // Only in lobyte/hibyte mode
{
	__asm__ volatile ("cli");

	outb(channel, count & 0xFF); // low byte
	outb(channel, (count & 0xFF00) >> 8); // high byte
	
	// TODO: make sure to set interrupts
}