#include <types.h>
#include <config.h>

#include "multiboot.h"
#include "sys.h"
#include <mem/gdt.h>
#include <mem/paging.h>
#include <mem/mem.h>

#include <vfs/node.h>

#include <task/idt.h>
#include <task/timer.h>
#include <task/task.h>
#include <linker/elf.h>

#include <ui/vt.h>
#include <dev/vgatxt.h>
#include <dev/ps2keyboard.h>

/*	The kernel's main procedure. This function is called in loader_.asm.
	This function calls the initializer functions for all system parts.
	It then loads the modules the kernel was given by the bootloader. 
	This function never returns : once multitasking is started for good,
	the execution flow of this function is never returned to. */
extern "C" void kmain(multiboot_info_t* mbd, int32_t magic) {
	ASSERT(magic == MULTIBOOT_BOOTLOADER_MAGIC);

	mem_placementAddr = ((size_t)&end & 0xFFFFF000) + 0x1000;
	mbd->cmdline += K_HIGHHALF_ADDR; mbd->mods_addr += K_HIGHHALF_ADDR;
	module_t *mods = (module_t*)mbd->mods_addr;
	for (unsigned i = 0; i < mbd->mods_count; i++) {
		mods[i].mod_start += K_HIGHHALF_ADDR;
		mods[i].mod_end += K_HIGHHALF_ADDR;
		mods[i].string += K_HIGHHALF_ADDR;
		if (mods[i].mod_end > mem_placementAddr)
			mem_placementAddr = (mods[i].mod_end & 0xFFFFF000) + 0x1000;
	}


	// Init memory managment functions
	idt_init();
	size_t totalRam = ((mbd->mem_upper + mbd->mem_lower) * 1024);
	paging_init(totalRam);
	gdt_init();
	paging_cleanup();
	_no_more_ksbrk = true;

	// Init higher level stuff
	timer_init(30);
	tasking_init();
	vfs_setup();

	// Init display devices
	text_display = new vgatxt(dot_dev);
	dot_dev->add_child("vgatxt", text_display);
	ke_vt = new vt(dot_dev, 80, 25);
	dot_ui->add_child("klog", ke_vt);
	ke_vt->outputTo(text_display);

	// Say hello
	ke_vt->fgcolor = TC_LIGHTGRAY;
	*ke_vt << "Hello. This is ";
	ke_vt->fgcolor = TC_WHITE; 		*ke_vt << K_OS_NAME;
	ke_vt->fgcolor = TC_LIGHTGRAY; 	*ke_vt << " version ";
	ke_vt->fgcolor = TC_WHITE; 		*ke_vt << K_OS_VER;
	ke_vt->fgcolor = TC_LIGHTGRAY;	*ke_vt << " codename '";
	ke_vt->fgcolor = TC_WHITE;		*ke_vt << K_OS_CODENAME;
	ke_vt->fgcolor = TC_LIGHTGRAY;	*ke_vt << "'. Enjoy!\n";

	// Init devices
	kbd = new ps2kbd(dot_dev);
	dot_dev->add_child("ps2kbd", kbd);

	// Load modules
	*ke_vt << "Loading modules :\n";
	for (unsigned i = 0; i < mbd->mods_count; i++) {
		*ke_vt << " * " << (char*)mods[i].string;
		if (elf_check((uint8_t*)mods[i].mod_start)) {
			*ke_vt << " : Invalid ELF file\n";
		} else {
			process *pr = elf_exec((uint8_t*)mods[i].mod_start, PL_USER);
			if (pr == 0) {
				*ke_vt << " : Error loading\n";
			} else {
				*ke_vt << " : OK, pid=" << (int)pr->pid << "\n";
			}
		}
	}

	*ke_vt << "Giving control to userland processes.\n\n";
	sti();
	schedule();
	PANIC("Should never happen. Something probably went wrong with multitasking.");
}