#include "process.h"
#include "alloc.h"
#include "interrupts.h"
#include "memory.h"
#include "thread.h"

#include "string.h"
#include <stdint.h>

struct pcb *create_process(uid_t uid)
{
	static pid_t pid = 1;
	struct pcb *new_pcb = kmalloc(sizeof(struct pcb));
	if (!new_pcb)
		return NULL;
	new_pcb->uid = uid;
	new_pcb->pid = pid++;
	new_pcb->tid = 1;

	new_pcb->heap = kalloc_pages(4096);
	if (!new_pcb->heap) {
		kfree(new_pcb);
		return NULL;
	}
	new_pcb->cr3 =
	    (void *)((uint32_t)VA2PTE((uint32_t)new_pcb->heap) & PAGE_MASK);
	memcpy(new_pcb->heap, PD, 4096);
	new_pcb->heap[1023] = (uint32_t) new_pcb->cr3 | INIT_FLAGS;

	new_pcb->daddy = NULL;
	new_pcb->children = NULL;
	new_pcb->next = new_pcb;
	new_pcb->prev = new_pcb;

	if (current_pcb) {
		new_pcb->next = current_pcb->next;
		new_pcb->prev = current_pcb;
		current_pcb->next = new_pcb;
		if (current_pcb->prev == current_pcb)
			current_pcb->prev = new_pcb;
	} else {
		current_pcb = new_pcb;
	}
	new_pcb->signals.pending = SIG_IGN;
	new_pcb->thread_list = NULL;

	return new_pcb;
}

void remove_process(struct pcb *pcb)
{
	struct pcb *left = pcb->prev;
	struct pcb *right = pcb->next;
	if (pcb->heap)
		kfree_pages(pcb->heap, 4096);
	left->next = right;
	right->prev = left;
	kfree(pcb);
}