#include <errcode.h>
#include <dtb.h>
#include <utils.h>
#include <string.h>
#include <uart.h>
#include <kmalloc.h>
#include <vector.h>

void *dtb_addr;

void fdt_callback(const char *path, const vector_t *cbs, const vector_t *props)
{
  for (int i = 0; i < (int)cbs->size; ++i)
    if (!strcmp(path, VEC_AT(fdt_callback_t, cbs, i)->name))
      VEC_AT(fdt_callback_t, cbs, i)->func(props);
}

uint32_t *fdt_struct_cur;

#define nextnode(ptr) (void *)((((uint64_t)(ptr) >> 2) + 1) << 2)
void traverse(const char *path, const vector_t *cbs)
{
  vector_t *props = make_vector(0);

  fdt_prop_t *prop;
  const fdt_prop_header_t *prop_header;
  const char *fdt_node_path = 0x0;

  for (;;) {
    fdt_struct_cur = ALIGN4(fdt_struct_cur);

    switch (ntoh32(*fdt_struct_cur)) {
    case FDT_BEGIN_NODE:
      BUMP(uint32_t, uint32_t, fdt_struct_cur);
      fdt_node_path = (void *)fdt_struct_cur;
      do {
        BUMP(uint32_t, char, fdt_struct_cur);
      } while (*(char *)fdt_struct_cur != '\0');
      BUMP(uint32_t, char, fdt_struct_cur); // '\0'

      fdt_struct_cur = ALIGN4(fdt_struct_cur);
      traverse(fdt_node_path, cbs);
      break;
    case FDT_END_NODE:
      fdt_struct_cur = nextnode(fdt_struct_cur);
      goto traverse_callback;
    case FDT_PROP:
      BUMP(uint32_t, uint32_t, fdt_struct_cur);
      prop_header = BUMP(uint32_t, fdt_prop_header_t, fdt_struct_cur);

      prop = kmalloc(sizeof(fdt_prop_t));
      prop->len = ntoh32(prop_header->len);
      prop->name = dtb_addr + 
                   ntoh32(((fdt_header_t *)dtb_addr)->off_dt_strings) +
                   ntoh32(prop_header->nameoff);
      prop->value = (void *)fdt_struct_cur;
      VEC_PUSH(props, prop);

      fdt_struct_cur = (void *)((uint64_t)fdt_struct_cur + 
                                ntoh32(prop_header->len));
      fdt_struct_cur = ALIGN4(fdt_struct_cur);
      break;
    case FDT_NOP:
      fdt_struct_cur = nextnode(fdt_struct_cur);
      break;
    case FDT_END:
      return;
    default:
      exit(ERR_UNREACHABLE);
    }
  }
traverse_callback:
  fdt_callback(path, cbs, props);
}

void fdt_traverse(const vector_t *cbs)
{
  fdt_struct_cur = dtb_addr + ntoh32(((fdt_header_t *)dtb_addr)->off_dt_struct);

  traverse("", cbs);
}