#pragma once
#include "stddef.h"
#include "stdlib.h"
// thank you osdev.
#define PIC1		0x20 // master PIC
#define PIC2		0xA0 // slave PIC
#define PIC1_COMMAND	PIC1
#define PIC1_DATA	(PIC1+1)
#define PIC2_COMMAND	PIC2
#define PIC2_DATA	(PIC2+1)
#define PIC_EOI		0x20
#define ICW1_ICW4	0x01		/* Indicates that ICW4 will be present */
#define ICW1_SINGLE	0x02		/* Single (cascade) mode */
#define ICW1_INTERVAL4	0x04		/* Call address interval 4 (8) */
#define ICW1_LEVEL	0x08		/* Level triggered (edge) mode */
#define ICW1_INIT	0x10		/* Initialization - required! */
#define ICW4_8086	0x01		/* 8086/88 (MCS-80/85) mode */
#define ICW4_AUTO	0x02		/* Auto (normal) EOI */
#define ICW4_BUF_SLAVE	0x08		/* Buffered mode/slave */
#define ICW4_BUF_MASTER	0x0C		/* Buffered mode/master */
#define ICW4_SFNM	0x10		/* Special fully nested (not) */
#define CASCADE_IRQ 2
#define IDT_MAX_DESCRIPTORS 32

typedef struct {
	uint16_t    isr_low;      // The lower 16 bits of the ISR's address
	uint16_t    kernel_cs;    // The GDT segment selector that the CPU will load into CS before calling the ISR
	uint8_t     reserved;     // Set to zero
	uint8_t     attributes;   // Type and attributes; see the IDT page
	uint16_t    isr_high;     // The higher 16 bits of the ISR's address
} __attribute__((packed)) idt_entry_t;
typedef struct {
	uint16_t	limit;
	uint32_t	base;
} __attribute__((packed)) idtr_t;
typedef struct {
   uint32_t ds;
   uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax;
   uint32_t int_no, err_code;
   uint32_t eip, cs, eflags, useresp, ss;
} INT_registers_t;

inline void PIC_sendEOI(uint8_t irq) {
	if (irq >= 8) { // slave also needs EOI
        outb(PIC2_COMMAND,PIC_EOI);
    }
	outb(PIC1_COMMAND,PIC_EOI);
}
void PIC_remap(int offset1, int offset2);
__attribute__((noreturn))
void INT_exhand(INT_registers_t regs);
void INT_IRQ(uint8_t IRQ, INT_registers_t regs);
void idt_set_descriptor(uint8_t vector, void* isr, uint8_t flags);
void idt_init();

__attribute__((aligned(0x10)))
extern idt_entry_t idt[256];
extern idtr_t idtr;
extern void* isr_stub_table[];
extern void* irq_stub_table[];
extern uint8_t INT_vectors[IDT_MAX_DESCRIPTORS];
extern char *exception_messages[];