#include <string.h>

#include "fh_print.h"
#include "fh_error.h"
#include "fh_runtime.h"
#include "fh_mem.h"

void fh_setbase(struct fh_thread_s *fh, uint32_t base) {
  LOG("BASE = %d", base);
  fh->base = base;
}

enum fh_error fh_fetch(struct fh_thread_s *fh, uint32_t addr, uint32_t *dst)
{
  switch (addr) {
    case MAGICADDR_BASE:
      *dst = fh->base;
      break;
      // TODO more magic

    default:
      if (addr & 3) {
        LOGE("Address 0x%08x is not aligned!", addr);
        return FH_ERR_ILLEGAL_FETCH;
      }
      if (addr < HEAP_SIZE - 4) {
        *dst = *((uint32_t*)&fh->heap[addr]);
      } else {
        LOGE("Address 0x%08x too high!", addr);
        return FH_ERR_ILLEGAL_FETCH;
      }
  }

  return FH_OK;
}

enum fh_error fh_fetch_char(struct fh_thread_s *fh, uint32_t addr, char *dst)
{
  if (addr < HEAP_SIZE - 4) {
    *dst = (char) fh->heap[addr];
  } else {
    LOGE("Address 0x%08x too high!", addr);
    return FH_ERR_ILLEGAL_FETCH;
  }

  return FH_OK;
}

enum fh_error fh_store(struct fh_thread_s *fh, uint32_t addr, uint32_t val)
{
  switch (addr) {
    case MAGICADDR_BASE:
      fh_setbase(fh, val);
      break;
      // TODO more magic

    default:
      if (addr & 3) {
        LOGE("Address 0x%08x is not aligned!", addr);
        return FH_ERR_ILLEGAL_FETCH;
      }
      if (addr <= HEAP_SIZE - 4) {
        *((uint32_t*)&fh->heap[addr]) = val;
      } else {
        LOGE("Address 0x%08x too high!", addr);
        return FH_ERR_ILLEGAL_FETCH;
      }
  }

  return FH_OK;
}

enum fh_error fh_store_char(struct fh_thread_s *fh, uint32_t addr, char val)
{
  if (addr < HEAP_SIZE) {
    fh->heap[addr] = val;
  } else {
    LOGE("Address 0x%08x too high!", addr);
    return FH_ERR_ILLEGAL_FETCH;
  }

  return FH_OK;
}

/** Allocate a heap region, e.g. for a string. The address is stored to `addr` */
enum fh_error fh_heap_reserve(
    struct fh_thread_s *fh,
    size_t len,
    uint32_t *addr
)
{
  uint32_t p = fh->heap_top;

  if (p + len > HEAP_SIZE) {
    return FH_ERR_HEAP_FULL;
  }

  *addr = p;

  fh->heap_top = WORDALIGNED(p + len);

  return FH_OK;
}

/** Write bytes to heap at a given location. The region must have been previously allocated! */
void fh_heap_write(struct fh_thread_s *fh, uint32_t addr, const void *src, uint32_t len)
{
  memcpy(&fh->heap[addr], src, len);
}

/** Allocate heap region and write bytes to it */
enum fh_error fh_heap_put(struct fh_thread_s *fh, const void *src, uint32_t len)
{
  enum fh_error rv;
  uint32_t addr;
  TRY(fh_heap_reserve(fh, len, &addr));
  fh_heap_write(fh, addr, src, len);
  return FH_OK;
}

/** Copy bytes from compile area to heap. The region must have been previously allocated! */
void fh_heap_copy_from_compile(struct fh_thread_s *fh, uint32_t addr, uint32_t srcaddr, uint32_t len)
{
  memcpy(&fh->heap[addr], &fh->compile[srcaddr], len);
}

/** Reserve space in the compile memory area */
enum fh_error fh_compile_reserve(
    struct fh_thread_s *fh,
    size_t len,
    uint32_t *addr
)
{
  uint32_t p = fh->compile_top; // FIXME this shouldn't be needed

  if (p + len > COMPILED_BUFFER_SIZE) {
    return FH_ERR_HEAP_FULL;
  }

  *addr = p;

  fh->compile_top = WORDALIGNED(p + len);

  return FH_OK;
}

/** Write bytes to compile area at a given location. The region must have been previously allocated! */
void fh_compile_write(struct fh_thread_s *fh, uint32_t addr, const void *src, uint32_t len)
{
  memcpy(&fh->compile[addr], src, len);
}

/** Allocate compile region and write bytes to it */
enum fh_error fh_compile_put(struct fh_thread_s *fh, const void *src, uint32_t len)
{
  enum fh_error rv;
  uint32_t addr;
  TRY(fh_compile_reserve(fh, len, &addr));
  fh_compile_write(fh, addr, src, len);
  return FH_OK;
}