// Interrupt Requests setup
// Author: xamidev
// Licensed under the Unlicense. See the repo below.
// https://github.com/xamidev/blankos

#include "system.h"
#include "io.h"
#include "idt.h"
#include "../libk/stdio.h"

extern void irq0();
extern void irq1();
extern void irq2();
extern void irq3();
extern void irq4();
extern void irq5();
extern void irq6();
extern void irq7();
extern void irq8();
extern void irq9();
extern void irq10();
extern void irq11();
extern void irq12();
extern void irq13();
extern void irq14();
extern void irq15();

void *irq_routines[16] =
{
	0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0
};

void irq_install_handler(int irq, void (*handler)(struct regs *r))
{
	irq_routines[irq] = handler;
}

void irq_uninstall_handler(int irq)
{
	irq_routines[irq] = 0;
}

void irq_remap(void)
{
	outb(0x20, 0x11);
	outb(0xA0, 0x11);
	outb(0x21, 0x20);
	outb(0xA1, 0x28);
	outb(0x21, 0x04);
	outb(0xA1, 0x02);
	outb(0x21, 0x01);
	outb(0xA1, 0x01);
	outb(0x21, 0x0);
	outb(0xA1, 0x0);
}

void irq_install()
{
	irq_remap();

	idt_set_gate(32, (unsigned)irq0, 0x08, 0x8E);
	idt_set_gate(33, (unsigned)irq1, 0x08, 0x8E);
	idt_set_gate(34, (unsigned)irq2, 0x08, 0x8E);
	idt_set_gate(35, (unsigned)irq3, 0x08, 0x8E);
	idt_set_gate(36, (unsigned)irq4, 0x08, 0x8E);
	idt_set_gate(37, (unsigned)irq5, 0x08, 0x8E);
	idt_set_gate(38, (unsigned)irq6, 0x08, 0x8E);
	idt_set_gate(39, (unsigned)irq7, 0x08, 0x8E);
	idt_set_gate(40, (unsigned)irq8, 0x08, 0x8E);
	idt_set_gate(41, (unsigned)irq9, 0x08, 0x8E);
	idt_set_gate(42, (unsigned)irq10, 0x08, 0x8E);
	idt_set_gate(43, (unsigned)irq11, 0x08, 0x8E);
	idt_set_gate(44, (unsigned)irq12, 0x08, 0x8E);
	idt_set_gate(45, (unsigned)irq13, 0x08, 0x8E);
	idt_set_gate(46, (unsigned)irq14, 0x08, 0x8E);
	idt_set_gate(47, (unsigned)irq15, 0x08, 0x8E);
	printf("[kernel] installed irq 0-15\n");
}

void irq_handler(struct regs *r)
{
	void (*handler)(struct regs *r);

	handler = irq_routines[r->int_no-32];
	if (handler)
	{
		handler(r);
	}

	if (r->int_no >= 40)
	{
		outb(0xA0, 0x20);
	}

	outb(0x20, 0x20);
}