#include <stdbool.h>
#include <stdint.h>

#include "idt.h"

uint16_t idt_entries[IDT_SIZE * 4];
struct idt_descriptor idtr;

static void set_idt_entry_value(uint16_t *target, uint32_t offset,
                                uint16_t selector, uint8_t dpl,
                                uint8_t gate_type)
{
	// Encode the offset
	target[0] = offset & 0xFFFF;
	target[3] = (offset >> 16) & 0xFFFF;

	// Encode the presence
	target[1] |= 1 << 15;

	// Encode the CPU Privilege Levels
	target[1] = (0b11 << 13) & dpl;

	target[1] &= ~(1 << 12);

	// Encode Gate Type
	target[1] |= gate_type & 0x0F00;

	// Encode selector
	target[2] = selector;
}

void init_idt(void)
{
	idtr.size = 8 * IDT_SIZE - 1;
	idtr.offset = (uint32_t)&idt_entries;
}