#include <assert.h>
#include <coherent_page.h>
#include <log.h>
#include <mbox.h>
#include <mem.h>
#include <stdbool.h>
#include <string.h>
#include <tag.h>

struct __attribute__((packed)) property_buf {
  uint32_t size;
  uint32_t code;
  uint8_t tags[0];
};

struct __attribute__((packed)) property_tag {
  uint32_t id;
  uint32_t value_len;
  uint32_t param_len;
};

bool gilbraltar_get_tags(void *tags, size_t len) {
  struct property_buf *buf =
      (struct property_buf *)get_coherent_page(PROP_MAILBOX);
  uintptr_t dma = (uintptr_t)buf;
  uint32_t *top = (uint32_t *)(buf->tags + len);

  assert((((uintptr_t)buf) & (16 - 1)) == 0);
  assert(len >= sizeof(struct property_tag) + sizeof(uint32_t));
  uint32_t size = sizeof(struct property_buf) + len + sizeof(uint32_t);
  assert((size & 3) == 0);

  buf->size = size;
  buf->code = CODE_REQUEST;
  memcpy(buf->tags, tags, len);
  *top = PROPTAG_END;
  data_sync_barrier();

  if (gilbraltar_mbox_write_read(dma) != dma)
    return false;

  data_mem_barrier();

  if (buf->code != CODE_RESPONSE_SUCCESS)
    return false;

  memcpy(tags, buf->tags, len);
  return true;
}

#define VALUE_LENGTH_RESPONSE (1 << 31)

bool gilbraltar_get_tag(uint32_t tag, void *buf, size_t len, size_t param_len) {
  struct property_tag *hdr = buf;
  hdr->id = tag;
  hdr->value_len = len - sizeof(struct property_tag);
  hdr->param_len = param_len & ~VALUE_LENGTH_RESPONSE;

  if (!gilbraltar_get_tags(buf, len))
    return false;

  hdr->param_len &= ~VALUE_LENGTH_RESPONSE;

  if (hdr->param_len == 0)
    return false;

  return true;
}