#include <stdbool.h>
#include <stddef.h>

#ifndef ZIVUOS_DISABLE_DYNAMIC
#include <malloc.h>
#endif

#include "process.h"
#include "kernel.h"
#include "models.h"
#include "state.h"

#ifndef ZV_ALLOC_STEP
#define ZV_ALLOC_STEP 0x08
#endif

void zv_kernel_init(
    zv_kernel_t *self, 
    zv_process_t **processes, 
    zv_pid_t processes_count
) {
    self->processes_stack = processes;
    self->processes_stack_size = processes_count;
#ifndef ZIVUOS_DISABLE_DYNAMIC
    self->is_dynamic = false;
#endif
}

zv_pid_t zv_kernel_count_processes(zv_kernel_t *self) {
    zv_pid_t result = 0;

    for (zv_pid_t count = 0; count < self->processes_stack_size; ++count) {
        if (self->processes_stack[count] == NULL) {
            continue;
        }

        ++result;
    }

    return result;
}

#ifndef ZIVUOS_DISABLE_DYNAMIC

static inline size_t zv_get_stack_size(zv_pid_t count) {
    return (count * sizeof(zv_process_t *));
}   

zv_kernel_t * zv_kernel_create() {
    zv_kernel_t *self = (zv_kernel_t *) malloc(sizeof(zv_kernel_t));
    
    if (self == NULL) {
        return NULL;
    }

#define STACK_SIZE zv_get_stack_size(ZV_ALLOC_STEP)
    zv_process_t **stack = (zv_process_t **) malloc(STACK_SIZE);
#undef STACK_SIZE

    if (stack == NULL) {
        free(self);
        return NULL;
    }

    zv_kernel_init(self, stack, ZV_ALLOC_STEP);
    self->is_dynamic = true;

    return self;
}

#endif