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

#include "multiboot.h"
#include "monitor.h"
#include "sys.h"
#include <task/idt.h>
#include <task/timer.h>
#include <task/task.h>
#include <mem/gdt.h>
#include <mem/paging.h>
#include <mem/mem.h>
#include <linker/elf.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);

	size_t totalRam = 0;
	uint32_t i;

	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 (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;
	}

	monitor_clear();

	monitor_write(K_OS_NAME);
	monitor_write(" version ");
	monitor_write(K_OS_VER);
	monitor_write(" codename '");
	monitor_write(K_OS_CODENAME);
	monitor_write("' starting up :\n");


	idt_init();

	totalRam = ((mbd->mem_upper + mbd->mem_lower) * 1024);
	paging_init(totalRam);
	gdt_init();
	paging_cleanup();
	_no_more_ksbrk = true;

	//kheap_init();
	timer_init(30);
	tasking_init();
	
	monitor_write("\nLoading modules :\n");
	for (i = 0; i < mbd->mods_count; i++) {
		monitor_write(" * ");
		monitor_write((char*)mods[i].string);
		if (elf_check((uint8_t*)mods[i].mod_start)) {
			monitor_write(" : Invalid ELF file\n");
		} else {
			process *pr = elf_exec((uint8_t*)mods[i].mod_start, PL_USER);
			if (pr == 0) {
				monitor_write(" : Error loading\n");
			} else {
				monitor_write(" : OK, pid="); monitor_writeDec(pr->pid); monitor_write("\n");
			}
		}
	}

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