// kernel.c
// Author: Josh Holtrop
// Date: 08/13/03
// Holtrop's Operating System - Version 0.13
// Modified: 03/08/04

#include "hos_defines.h"	//#DEFINE's for kernel

#include "functions.h"		//general functions
#include "asmfuncs.h"		//assembly functions
#include "kio.h"		//kernel input/output functions
#include "mm/mm.h"		//physical memory management functions
#include "mm/vmm.h"		//virtual memory management & paging functions
#include "char/keyboard.h"	//generic keyboard driver & functions
#include "char/mouse.h"		//generic ps/2 mouse driver & functions
#include "block/fdc.h"		//Floppy Disk Controller functions
#include "sys/cmos.h"		//CMOS interface functions
#include "sys/io.h"		//port i/o functions
#include "sys/pic.h"		//Programmable Interrupt Controller functions
#include "sys/rtc.h"		//Real Time Clock functions
#include "video/video.h"	//video functions
#include "fs/vfs.h"

extern "C" {

void isr(dword num);
void k_init();

dword	timer = 0;

//Main kernel initialization method
void k_init()
{
		// ===== Initialization
	fdc_sendDOR(0x0C);		//turn off floppy motor!!
	mm_init();
	vmm_init();
	video_init();
	kio_init();
	kio_console_cls();
	pic_remap(0x20, 0x28);
	timer_init();
	mouse_init();
	pic_mask1(0);			//unmask IRQ's 0-7
	pic_mask2(0);			//unmask IRQ's 8-15
	enable_ints();
	kbd_resetLEDs();		//after enabling interrupts!!
	if (video_Mode())
	{
		int w = video_getWidth(), h = video_getHeight();
		int p = w * h - 1;
		for (; p >= 0; p--)
			video_pseti(p, 0x00000075);
		int x = w >> 1, y = h >> 1, sz = h >> 1;
		for (p = 0; p <= sz; p += 24)
		{
			video_line(x + p, y, x, y + sz - p, 0x0000FF00);
			video_line(x + p, y, x, y - sz + p, 0x0000FF00);
			video_line(x - p, y, x, y + sz - p, 0x0000FF00);
			video_line(x - p, y, x, y - sz + p, 0x0000FF00);
		}
		kio_drawConsole();
	}

	printf("HOS 0.14 - Kernel File Size: %uKb Mem Used: %uKb\n", kernel_size()>>10, kernel_size_used()>>10);
	printf("Memory available to OS: %u MB (%u bytes)\n", mm_getTotalMegs(), mm_getTotalMem());
	printf("Free memory: %u bytes (%u pages)\n", mm_freemem(), mm_freemem()>>12);
	printf("Built on %s at %s\n", __DATE__, __TIME__);
	printf("%b/%b/%b %b:%b:%b\n", rtc_readMonth(), rtc_readDay(), rtc_readYear(), rtc_readHour(), rtc_readMinute(), rtc_readSecond());
	
	vfs_init();
	
	dword key = 0;
	for (;;)
	{
		key = kbdWaitKey();
		if ((key & 0xFF) > 2)	//key is not a control key
			putc(key);
	}
}

// main Interrupt Service Routine - handles all interrupts unless caught by kernel.asm
void isr(dword num)
{
	switch(num)
	{
	case 14:
		printf("Page fault, CR2 = 0x%x\n", read_cr2());
		halt();
		break;
	case 0x20:         		// IRQ0 - timer interrupt
		timer++;
		(*(byte *)(0xc00b8000))++;
		if (!(timer % 100))
		{
			dword curPos = kio_getCursorPosition();
			kio_writeCursorPosition(72);
			printf("%b:%b:%b\n", rtc_readHour(), rtc_readMinute(), rtc_readSecond());
			kio_writeCursorPosition(curPos);
		}
		pic_eoi();
		break;
	case 0x21:  			// IRQ1 - keyboard interrupt
		isr_keyboard();    	//isr_keybard() takes care of calling eoi()
		break;
	case 0x2C:			// IRQ12 - PS/2 mouse
		isr_mouse();
		pic_eoi2();
		break;
	default:
		printf("Interrupt %d (0x%x) Unhandled!!\n", num, num);
		halt();
		break;
	}
}

}