#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifndef _XOPEN_SOURCE
#define _XOPEN_SOURCE 600 /* PTHREAD_MUTEX_RECURSIVE */
#endif

#include <stdlib.h>
#include <stdio.h>
#include <assert.h>

#if defined(HAVE_EXECINFO_H)
#include <execinfo.h>
#endif

static void
show_stackframe()
{
#if defined HAVE_EXECINFO_H && defined backtrace_size_t && defined HAVE_BACKTRACE
  void *trace[16];
  backtrace_size_t trace_size = backtrace(trace, 16);
  char **messages = backtrace_symbols(trace, trace_size);

  fprintf(stderr, "[bt] Execution path:\n");
  if (messages)
    {
      for (backtrace_size_t i = 0; i < trace_size; ++i) fprintf(stderr, "[bt] %s\n", messages[i]);
      free(messages);
    }
#endif
}

#include "dmemory.h"
#include "resource_handle.h"
#include "namespace.h"
#include "serialize.h"
#include "cdi.h"
#include "error.h"
#include "file.h"
#include "resource_unpack.h"
#include "institution.h"
#include "model.h"

enum
{
  MIN_LIST_SIZE = 128
};

static void listInitialize(void);

typedef struct listElem
{
  union
  {
    /* free-list management data */
    struct
    {
      int next, prev;
    } free;
    /* holding an actual value */
    struct
    {
      const resOps *ops;
      void *val;  // ptr
    } v;
  } res;
  int status;
} listElem_t;

struct resHList_t
{
  int size, freeHead, hasDefaultRes;
  listElem_t *resources;
};

static struct resHList_t *resHList;

static int resHListSize = 0;

#if defined(HAVE_LIBPTHREAD)
#include <pthread.h>

static pthread_once_t listInitThread = PTHREAD_ONCE_INIT;
static pthread_mutex_t listMutex;

#define LIST_LOCK() pthread_mutex_lock(&listMutex)
#define LIST_UNLOCK() pthread_mutex_unlock(&listMutex)
#define LIST_INIT(init0)                                                       \
  do                                                                           \
    {                                                                          \
      pthread_once(&listInitThread, listInitialize);                           \
      pthread_mutex_lock(&listMutex);                                          \
      if ((init0) && (!resHList || !resHList[0].resources)) reshListCreate(0); \
      pthread_mutex_unlock(&listMutex);                                        \
    }                                                                          \
  while (0)

#else

static int listInit = 0;

#define LIST_LOCK()
#define LIST_UNLOCK()
#define LIST_INIT(init0)                                                           \
  do                                                                               \
    {                                                                              \
      if (!listInit)                                                               \
        {                                                                          \
          listInitialize();                                                        \
          if ((init0) && (!resHList || !resHList[0].resources)) reshListCreate(0); \
          listInit = 1;                                                            \
        }                                                                          \
    }                                                                              \
  while (0)

#endif

/**************************************************************/

static void
listInitResources(int nsp)
{
  xassert(nsp < resHListSize && nsp >= 0);
  int size = resHList[nsp].size = MIN_LIST_SIZE;
  xassert(resHList[nsp].resources == NULL);
  resHList[nsp].resources = (listElem_t *) Calloc(MIN_LIST_SIZE, sizeof(listElem_t));
  listElem_t *p = resHList[nsp].resources;

  for (int i = 0; i < size; i++)
    {
      p[i].res.free.next = i + 1;
      p[i].res.free.prev = i - 1;
      p[i].status = RESH_UNUSED;
    }

  p[size - 1].res.free.next = -1;
  resHList[nsp].freeHead = 0;
  int oldNsp = namespaceGetActive();
  namespaceSetActive(nsp);
  instituteDefaultEntries();
  modelDefaultEntries();
  namespaceSetActive(oldNsp);
}

static inline void
reshListClearEntry(int i)
{
  resHList[i].size = 0;
  resHList[i].resources = NULL;
  resHList[i].freeHead = -1;
}

void
reshListCreate(int namespaceID)
{
  LIST_INIT(namespaceID != 0);
  LIST_LOCK();
  if (resHListSize <= namespaceID)
    {
      resHList = (struct resHList_t *) Realloc(resHList, (size_t) (namespaceID + 1) * sizeof(resHList[0]));
      for (int i = resHListSize; i <= namespaceID; ++i) reshListClearEntry(i);
      resHListSize = namespaceID + 1;
    }
  listInitResources(namespaceID);
  LIST_UNLOCK();
}

/**************************************************************/

void
reshListDestruct(int namespaceID)
{
  LIST_LOCK();
  xassert(resHList && namespaceID >= 0 && namespaceID < resHListSize);
  int callerNamespaceID = namespaceGetActive();
  namespaceSetActive(namespaceID);
  if (resHList[namespaceID].resources)
    {
      for (int j = 0; j < resHList[namespaceID].size; j++)
        {
          listElem_t *listElem = resHList[namespaceID].resources + j;
          if (listElem->status & RESH_IN_USE_BIT) listElem->res.v.ops->valDestroy(listElem->res.v.val);
        }
      Free(resHList[namespaceID].resources);
      resHList[namespaceID].resources = NULL;
      reshListClearEntry(namespaceID);
    }
  if (resHList[callerNamespaceID].resources) namespaceSetActive(callerNamespaceID);
  LIST_UNLOCK();
}

static void
listDestroy(void)
{
  LIST_LOCK();
  for (int i = resHListSize; i > 0; --i)
    if (resHList[i - 1].resources) namespaceDelete(i - 1);
  resHListSize = 0;
  Free(resHList);
  resHList = NULL;
  cdiReset();
  LIST_UNLOCK();
}

/**************************************************************/

static void
listInitialize(void)
{
#if defined(HAVE_LIBPTHREAD)
  pthread_mutexattr_t ma;
  pthread_mutexattr_init(&ma);
  pthread_mutexattr_settype(&ma, PTHREAD_MUTEX_RECURSIVE);
  /* initialize global API mutex lock */
  pthread_mutex_init(&listMutex, &ma);
  pthread_mutexattr_destroy(&ma);
#endif
  /* file is special and has its own table, which needs to be
   * created, before we register the listDestroy exit handler */
  {
    int null_id;
    null_id = fileOpen_serial("/dev/null", "r");
    if (null_id != -1) fileClose_serial(null_id);
  }
  atexit(listDestroy);
}

/**************************************************************/

static void
listSizeExtend()
{
  int nsp = namespaceGetActive();
  int oldSize = resHList[nsp].size;
  size_t newListSize = (size_t) oldSize + MIN_LIST_SIZE;

  resHList[nsp].resources = (listElem_t *) Realloc(resHList[nsp].resources, newListSize * sizeof(listElem_t));

  listElem_t *r = resHList[nsp].resources;
  for (size_t i = (size_t) oldSize; i < newListSize; ++i)
    {
      r[i].res.free.next = (int) i + 1;
      r[i].res.free.prev = (int) i - 1;
      r[i].status = RESH_UNUSED;
    }

  if (resHList[nsp].freeHead != -1) r[resHList[nsp].freeHead].res.free.prev = (int) newListSize - 1;
  r[newListSize - 1].res.free.next = resHList[nsp].freeHead;
  r[oldSize].res.free.prev = -1;
  resHList[nsp].freeHead = oldSize;
  resHList[nsp].size = (int) newListSize;
}

/**************************************************************/

static void
reshPut_(int nsp, int entry, void *p, const resOps *ops)
{
  listElem_t *newListElem = resHList[nsp].resources + entry;
  int next = newListElem->res.free.next, prev = newListElem->res.free.prev;
  if (next != -1) resHList[nsp].resources[next].res.free.prev = prev;
  if (prev != -1)
    resHList[nsp].resources[prev].res.free.next = next;
  else
    resHList[nsp].freeHead = next;
  newListElem->res.v.val = p;
  newListElem->res.v.ops = ops;
  newListElem->status = RESH_DESYNC_IN_USE;
}

int
reshPut(void *p, const resOps *ops)
{
  xassert(p && ops);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();

  if (resHList[nsp].freeHead == -1) listSizeExtend();
  int entry = resHList[nsp].freeHead;
  cdiResH resH = namespaceIdxEncode2(nsp, entry);
  reshPut_(nsp, entry, p, ops);

  LIST_UNLOCK();

  return resH;
}

/**************************************************************/

static void
reshRemove_(int nsp, int idx)
{
  int curFree = resHList[nsp].freeHead;
  listElem_t *r = resHList[nsp].resources;
  r[idx].res.free.next = curFree;
  r[idx].res.free.prev = -1;
  if (curFree != -1) r[curFree].res.free.prev = idx;
  r[idx].status = RESH_DESYNC_DELETED;
  resHList[nsp].freeHead = idx;
}

void
reshDestroy(cdiResH resH)
{
  int nsp;
  namespaceTuple_t nspT;

  LIST_LOCK();

  nsp = namespaceGetActive();

  nspT = namespaceResHDecode(resH);

  xassert(nspT.nsp == nsp && nspT.idx >= 0 && nspT.idx < resHList[nsp].size && resHList[nsp].resources[nspT.idx].res.v.ops);

  if (resHList[nsp].resources[nspT.idx].status & RESH_IN_USE_BIT) reshRemove_(nsp, nspT.idx);

  LIST_UNLOCK();
}

void
reshRemove(cdiResH resH, const resOps *ops)
{
  int nsp;
  namespaceTuple_t nspT;

  LIST_LOCK();

  nsp = namespaceGetActive();

  nspT = namespaceResHDecode(resH);

  xassert(nspT.nsp == nsp && nspT.idx >= 0 && nspT.idx < resHList[nsp].size
          && (resHList[nsp].resources[nspT.idx].status & RESH_IN_USE_BIT) && resHList[nsp].resources[nspT.idx].res.v.ops
          && resHList[nsp].resources[nspT.idx].res.v.ops == ops);

  reshRemove_(nsp, nspT.idx);

  LIST_UNLOCK();
}

/**************************************************************/

void
reshReplace(cdiResH resH, void *p, const resOps *ops)
{
  xassert(p && ops);
  LIST_INIT(1);
  LIST_LOCK();
  int nsp = namespaceGetActive();
  namespaceTuple_t nspT = namespaceResHDecode(resH);
  while (resHList[nsp].size <= nspT.idx) listSizeExtend();
  listElem_t *q = resHList[nsp].resources + nspT.idx;
  if (q->status & RESH_IN_USE_BIT)
    {
      q->res.v.ops->valDestroy(q->res.v.val);
      reshRemove_(nsp, nspT.idx);
    }
  reshPut_(nsp, nspT.idx, p, ops);
  LIST_UNLOCK();
}

static listElem_t *
reshGetElem(const char *caller, const char *expressionString, cdiResH resH, const resOps *ops)
{
  listElem_t *listElem;
  xassert(ops);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();

  namespaceTuple_t nspT = namespaceResHDecode(resH);
  assert(nspT.idx >= 0);

  if (nspT.nsp == nsp && nspT.idx < resHList[nsp].size)
    {
      listElem = resHList[nsp].resources + nspT.idx;
      LIST_UNLOCK();
    }
  else
    {
      LIST_UNLOCK();
      show_stackframe();

      if (resH == CDI_UNDEFID)
        {
          xabortC(caller,
                  "Error while trying to resolve the ID \"%s\" in `%s()`: the value is CDI_UNDEFID (= %d).\n\tThis is most likely "
                  "the result of a failed earlier call. Please check the IDs returned by CDI.",
                  expressionString, caller, resH);
        }
      else
        {
          xabortC(caller,
                  "Error while trying to resolve the ID \"%s\" in `%s()`: the value is garbage (= %d, which resolves to namespace "
                  "= %d, index = %d).\n\tThis is either the result of using an uninitialized variable,\n\tof using a value as an "
                  "ID that is not an ID,\n\tor of using an ID after it has been invalidated.",
                  expressionString, caller, resH, nspT.nsp, nspT.idx);
        }
    }

  if (!(listElem && listElem->res.v.ops == ops))
    {
      show_stackframe();

      xabortC(caller, "Error while trying to resolve the ID \"%s\" in `%s()`: list element not found. The failed ID is %d",
              expressionString, caller, (int) resH);
    }

  return listElem;
}

void *
reshGetValue(const char *caller, const char *expressionString, cdiResH resH, const resOps *ops)
{
  return reshGetElem(caller, expressionString, resH, ops)->res.v.val;
}

/**************************************************************/

void
reshGetResHListOfType(unsigned numIDs, int resHs[], const resOps *ops)
{
  xassert(resHs && ops);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();
  unsigned j = 0;
  for (int i = 0; i < resHList[nsp].size && j < numIDs; i++)
    if ((resHList[nsp].resources[i].status & RESH_IN_USE_BIT) && resHList[nsp].resources[i].res.v.ops == ops)
      resHs[j++] = namespaceIdxEncode2(nsp, i);

  LIST_UNLOCK();
}

enum cdiApplyRet
cdiResHApply(enum cdiApplyRet (*func)(int id, void *res, const resOps *p, void *data), void *data)
{
  xassert(func);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();
  enum cdiApplyRet ret = CDI_APPLY_GO_ON;
  for (int i = 0; i < resHList[nsp].size && ret > 0; ++i)
    if (resHList[nsp].resources[i].status & RESH_IN_USE_BIT)
      ret = func(namespaceIdxEncode2(nsp, i), resHList[nsp].resources[i].res.v.val, resHList[nsp].resources[i].res.v.ops, data);
  LIST_UNLOCK();
  return ret;
}

enum cdiApplyRet
cdiResHFilterApply(const resOps *p, enum cdiApplyRet (*func)(int id, void *res, void *data), void *data)
{
  xassert(p && func);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();
  enum cdiApplyRet ret = CDI_APPLY_GO_ON;
  listElem_t *r = resHList[nsp].resources;
  for (int i = 0; i < resHList[nsp].size && ret > 0; ++i)
    if ((r[i].status & RESH_IN_USE_BIT) && r[i].res.v.ops == p) ret = func(namespaceIdxEncode2(nsp, i), r[i].res.v.val, data);
  LIST_UNLOCK();
  return ret;
}

/**************************************************************/

unsigned
reshCountType(const resOps *ops)
{
  unsigned countType = 0;

  xassert(ops);

  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();

  listElem_t *r = resHList[nsp].resources;
  size_t len = (size_t) resHList[nsp].size;
  for (size_t i = 0; i < len; i++) countType += ((r[i].status & RESH_IN_USE_BIT) && r[i].res.v.ops == ops);

  LIST_UNLOCK();

  return countType;
}

/**************************************************************/

int
reshResourceGetPackSize_intern(int resH, const resOps *ops, void *context, const char *caller, const char *expressionString)
{
  listElem_t *curr = reshGetElem(caller, expressionString, resH, ops);
  return curr->res.v.ops->valGetPackSize(curr->res.v.val, context);
}

void
reshPackResource_intern(int resH, const resOps *ops, void *buf, int buf_size, int *position, void *context, const char *caller,
                        const char *expressionString)
{
  listElem_t *curr = reshGetElem(caller, expressionString, resH, ops);
  curr->res.v.ops->valPack(curr->res.v.val, buf, buf_size, position, context);
}

enum
{
  resHPackHeaderNInt = 2,
  resHDeleteNInt = 2,
};

static int
getPackBufferSize(void *context)
{
  int intpacksize, packBufferSize = 0;

  int nsp = namespaceGetActive();

  /* pack start marker, namespace and sererator marker */
  packBufferSize += resHPackHeaderNInt * (intpacksize = serializeGetSize(1, CDI_DATATYPE_INT, context));

  /* pack resources, type marker and seperator marker */
  listElem_t *r = resHList[nsp].resources;
  for (int i = 0; i < resHList[nsp].size; i++)
    if (r[i].status & RESH_SYNC_BIT)
      {
        if (r[i].status == RESH_DESYNC_DELETED)
          {
            packBufferSize += resHDeleteNInt * intpacksize;
          }
        else if (r[i].status == RESH_DESYNC_IN_USE)
          {
            xassert(r[i].res.v.ops);
            /* packed resource plus 1 int for type */
            packBufferSize += r[i].res.v.ops->valGetPackSize(r[i].res.v.val, context) + intpacksize;
          }
      }
  /* end marker */
  packBufferSize += intpacksize;

  return packBufferSize;
}

/**************************************************************/

void
reshPackBufferDestroy(char **buffer)
{
  if (buffer) free(*buffer);
}

/**************************************************************/

int
reshGetTxCode(cdiResH resH)
{
  int type = 0;

  LIST_LOCK();

  int nsp = namespaceGetActive();

  namespaceTuple_t nspT = namespaceResHDecode(resH);
  assert(nspT.idx >= 0);

  if (nspT.nsp == nsp && nspT.idx < resHList[nsp].size)
    {
      listElem_t *listElem = resHList[nsp].resources + nspT.idx;
      xassert(listElem->res.v.ops);
      type = listElem->res.v.ops->valTxCode();
    }

  LIST_UNLOCK();

  return type;
}

/**************************************************************/

int
reshPackBufferCreate(char **packBuffer, int *packBufferSize, void *context)
{
  int packBufferPos = 0;
  int end = END;

  xassert(packBuffer);

  LIST_LOCK();

  int nsp = namespaceGetActive();

  int pBSize = *packBufferSize = getPackBufferSize(context);
  char *pB = *packBuffer = (char *) Malloc((size_t) pBSize);

  {
    int header[resHPackHeaderNInt] = { START, nsp };
    serializePack(header, resHPackHeaderNInt, CDI_DATATYPE_INT, pB, pBSize, &packBufferPos, context);
  }

  listElem_t *r = resHList[nsp].resources;
  for (int i = 0; i < resHList[nsp].size; i++)
    if (r[i].status & RESH_SYNC_BIT)
      {
        if (r[i].status == RESH_DESYNC_DELETED)
          {
            int temp[resHDeleteNInt] = { RESH_DELETE, namespaceIdxEncode2(nsp, i) };
            serializePack(temp, resHDeleteNInt, CDI_DATATYPE_INT, pB, pBSize, &packBufferPos, context);
          }
        else
          {
            listElem_t *curr = r + i;
            xassert(curr->res.v.ops);
            int type = curr->res.v.ops->valTxCode();
            if (!type) continue;
            serializePack(&type, 1, CDI_DATATYPE_INT, pB, pBSize, &packBufferPos, context);
            curr->res.v.ops->valPack(curr->res.v.val, pB, pBSize, &packBufferPos, context);
          }
        r[i].status &= ~RESH_SYNC_BIT;
      }

  LIST_UNLOCK();

  serializePack(&end, 1, CDI_DATATYPE_INT, pB, pBSize, &packBufferPos, context);

  return packBufferPos;
}

/**************************************************************/

/* for thread safety this feature would have to be integrated in reshPut */

void
reshSetStatus(cdiResH resH, const resOps *ops, int status)
{
  int nsp;
  namespaceTuple_t nspT;
  listElem_t *listElem;

  xassert((ops != NULL) ^ !(status & RESH_IN_USE_BIT));

  LIST_INIT(1);

  LIST_LOCK();

  nsp = namespaceGetActive();

  nspT = namespaceResHDecode(resH);

  xassert(nspT.nsp == nsp && nspT.idx >= 0 && nspT.idx < resHList[nsp].size);

  xassert(resHList[nsp].resources);
  listElem = resHList[nsp].resources + nspT.idx;

  xassert((!ops || (listElem->res.v.ops == ops)) && (listElem->status & RESH_IN_USE_BIT) == (status & RESH_IN_USE_BIT));

  listElem->status = status;

  LIST_UNLOCK();
}

/**************************************************************/

int
reshGetStatus(cdiResH resH, const resOps *ops)
{
  LIST_INIT(1);

  LIST_LOCK();

  int nsp = namespaceGetActive();

  namespaceTuple_t nspT = namespaceResHDecode(resH);

  xassert(nspT.nsp == nsp && nspT.idx >= 0);

  int status = RESH_UNUSED;
  if (nspT.idx < resHList[nsp].size)
    {
      listElem_t *listElem = resHList[nsp].resources + nspT.idx;
      const resOps *elemOps = listElem->res.v.ops;
      xassert(listElem && (!(listElem->status & RESH_IN_USE_BIT) || elemOps == ops));
      status = listElem->status;
    }

  LIST_UNLOCK();

  return status;
}

/**************************************************************/

void
reshLock()
{
  LIST_LOCK();
}

/**************************************************************/

void
reshUnlock()
{
  LIST_UNLOCK();
}

/**************************************************************/

int
reshListCompare(int nsp0, int nsp1)
{
  LIST_INIT(1);
  LIST_LOCK();

  xassert(resHListSize > nsp0 && resHListSize > nsp1 && nsp0 >= 0 && nsp1 >= 0);

  int valCompare = 0;
  int i, listSizeMin = (resHList[nsp0].size <= resHList[nsp1].size) ? resHList[nsp0].size : resHList[nsp1].size;
  listElem_t *resources0 = resHList[nsp0].resources, *resources1 = resHList[nsp1].resources;
  for (i = 0; i < listSizeMin; i++)
    {
      int occupied0 = (resources0[i].status & RESH_IN_USE_BIT) != 0, occupied1 = (resources1[i].status & RESH_IN_USE_BIT) != 0;
      /* occupation mismatch ? */
      int diff = occupied0 ^ occupied1;
      valCompare |= (diff << cdiResHListOccupationMismatch);
      if (!diff && occupied0)
        {
          /* both occupied, do resource types match? */
          diff = (resources0[i].res.v.ops != resources1[i].res.v.ops || resources0[i].res.v.ops == NULL);
          valCompare |= (diff << cdiResHListResourceTypeMismatch);
          if (!diff)
            {
              /* types match, does content match also? */
              diff = resources0[i].res.v.ops->valCompare(resources0[i].res.v.val, resources1[i].res.v.val);
              valCompare |= (diff << cdiResHListResourceContentMismatch);
            }
        }
    }
  /* find resources in nsp 0 beyond end of nsp 1 */
  for (int j = listSizeMin; j < resHList[nsp0].size; ++j)
    valCompare |= (((resources0[j].status & RESH_IN_USE_BIT) != 0) << cdiResHListOccupationMismatch);
  /* find resources in nsp 1 beyond end of nsp 0 */
  for (; i < resHList[nsp1].size; ++i)
    valCompare |= (((resources1[i].status & RESH_IN_USE_BIT) != 0) << cdiResHListOccupationMismatch);

  LIST_UNLOCK();

  return valCompare;
}

/**************************************************************/

void
reshListPrint(FILE *fp)
{
  int i, j, temp;
  listElem_t *curr;

  LIST_INIT(1);

  temp = namespaceGetActive();

  fprintf(fp, "\n\n##########################################\n#\n#  print "
              "global resource list \n#\n");

  for (i = 0; i < namespaceGetNumber(); i++)
    {
      namespaceSetActive(i);

      fprintf(fp, "\n");
      fprintf(fp, "##################################\n");
      fprintf(fp, "#\n");
      fprintf(fp, "# namespace=%d\n", i);
      fprintf(fp, "#\n");
      fprintf(fp, "##################################\n\n");

      fprintf(fp, "resHList[%d].size=%d\n", i, resHList[i].size);

      for (j = 0; j < resHList[i].size; j++)
        {
          curr = resHList[i].resources + j;
          if (!(curr->status & RESH_IN_USE_BIT))
            {
              curr->res.v.ops->valPrint(curr->res.v.val, fp);
              fprintf(fp, "\n");
            }
        }
    }
  fprintf(fp, "#\n#  end global resource list"
              "\n#\n##########################################\n\n");

  namespaceSetActive(temp);
}

/*
 * Local Variables:
 * c-file-style: "Java"
 * c-basic-offset: 2
 * indent-tabs-mode: nil
 * show-trailing-whitespace: t
 * require-trailing-newline: t
 * End:
 */
