#include <stddef.h>
#include "irq.h"
#include "gic.h"

static isr_ptr callbacks[1024] = { NULL };

static isr_ptr callback(uint16_t number);

void __attribute__((interrupt)) irq_handler(void) {
	uint16_t irq = gic_acnowledge_interrupt();
	isr_ptr isr = callback(irq);
	if (isr != NULL) {
		isr();
	}
	gic_end_interrupt(irq);
}

irq_error irq_register_isr(uint16_t irq_number, isr_ptr callback) {
	if (irq_number > MAX_ISR) {
		return IRQ_INVALID_IRQ_ID;
	} else if (callbacks[irq_number] != NULL) {
		return IRQ_ALREADY_REGISTERED;
	} else {
		callbacks[irq_number] = callback;
	}
	return IRQ_OK;
}

static isr_ptr callback(uint16_t number) {
	if (number > MAX_ISR) {
		return NULL;
	}
	return callbacks[number];
}