#include <stdint.h>
#include <stddef.h>
#include "system.h"

typedef struct {
	uint16_t base_low;
	uint16_t selector;
	uint8_t always0;
	uint8_t access_bits;
	uint16_t base_high;
} __attribute__((packed)) IDT_Entry;

typedef struct {
	uint16_t limit;
	uint32_t base;
} __attribute__((packed)) IDT_Pointer;

typedef struct {
	uint32_t gs, fs, es, ds;
	uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax;
	uint32_t int_no, err_code;
	uint32_t eip, cs, eflags, useresp, ss;
} Registers;

IDT_Entry idt[256] = { 0 };
IDT_Pointer idtp;

extern void flush_idt();
extern void isr0();
extern void isr1();
extern void isr2();
extern void isr3();
extern void isr4();
extern void isr5();
extern void isr6();
extern void isr7();
extern void isr8();
extern void isr9();
extern void isr10();
extern void isr11();
extern void isr12();
extern void isr13();
extern void isr14();
extern void isr15();
extern void isr16();
extern void isr17();
extern void isr18();
extern void isr19();
extern void isr20();
extern void isr21();
extern void isr22();
extern void isr23();
extern void isr24();
extern void isr25();
extern void isr26();
extern void isr27();
extern void isr28();
extern void isr29();
extern void isr30();
extern void isr31();

void isrs_handler(Registers *reg) {
	puts("EXCEPTION ");
	putc(reg->int_no + '0');
	for (;;);
}

void set_idt_gate(size_t num, uint32_t base, uint16_t selector, uint8_t access_bits) {
	idt[num].base_low = base & 0xFFFF;
	idt[num].base_high = base >> 16 & 0xFFFF;
	idt[num].selector = selector;
	idt[num].access_bits = access_bits;
	idt[num].always0 = 0;
}

void install_idt() {
	idtp.base = (uint32_t) &idt;
	idtp.limit = sizeof(idt) - 1;

	set_idt_gate(0, (uint32_t) isr0, 0x08, 0x8E);
	set_idt_gate(1, (uint32_t) isr1, 0x08, 0x8E); // comment
	set_idt_gate(2, (uint32_t) isr2, 0x08, 0x8E);
	set_idt_gate(3, (uint32_t) isr3, 0x08, 0x8E);
	set_idt_gate(4, (uint32_t) isr4, 0x08, 0x8E);
	set_idt_gate(5, (uint32_t) isr5, 0x08, 0x8E);
	set_idt_gate(6, (uint32_t) isr6, 0x08, 0x8E);
	set_idt_gate(7, (uint32_t) isr7, 0x08, 0x8E);
	set_idt_gate(8, (uint32_t) isr8, 0x08, 0x8E);
	set_idt_gate(9, (uint32_t) isr9, 0x08, 0x8E);
	set_idt_gate(10, (uint32_t) isr10, 0x08, 0x8E);
	set_idt_gate(11, (uint32_t) isr11, 0x08, 0x8E);
	set_idt_gate(12, (uint32_t) isr12, 0x08, 0x8E);
	set_idt_gate(13, (uint32_t) isr13, 0x08, 0x8E);
	set_idt_gate(14, (uint32_t) isr14, 0x08, 0x8E);
	set_idt_gate(15, (uint32_t) isr15, 0x08, 0x8E);
	set_idt_gate(16, (uint32_t) isr16, 0x08, 0x8E);
	set_idt_gate(17, (uint32_t) isr17, 0x08, 0x8E);
	set_idt_gate(18, (uint32_t) isr18, 0x08, 0x8E);
	set_idt_gate(19, (uint32_t) isr19, 0x08, 0x8E);
	set_idt_gate(20, (uint32_t) isr20, 0x08, 0x8E);
	set_idt_gate(21, (uint32_t) isr21, 0x08, 0x8E);
	set_idt_gate(22, (uint32_t) isr22, 0x08, 0x8E);
	set_idt_gate(23, (uint32_t) isr23, 0x08, 0x8E);
	set_idt_gate(24, (uint32_t) isr24, 0x08, 0x8E);
	set_idt_gate(25, (uint32_t) isr25, 0x08, 0x8E);
	set_idt_gate(26, (uint32_t) isr26, 0x08, 0x8E);
	set_idt_gate(27, (uint32_t) isr27, 0x08, 0x8E);
	set_idt_gate(28, (uint32_t) isr28, 0x08, 0x8E);
	set_idt_gate(29, (uint32_t) isr29, 0x08, 0x8E);
	set_idt_gate(30, (uint32_t) isr30, 0x08, 0x8E);
	set_idt_gate(31, (uint32_t) isr31, 0x08, 0x8E);

	flush_idt();
}