/*
 * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
 *
 * This program is free software: you can use, redistribute, and/or modify
 * it under the terms of the GNU Affero General Public License, version 3
 * or later ("AGPL"), as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "streamInc.h"

static int32_t streamTaskExecImpl(SStreamTask* pTask, void* data, SArray* pRes) {
  void* exec = pTask->exec.executor;

  // set input
  SStreamQueueItem* pItem = (SStreamQueueItem*)data;
  if (pItem->type == STREAM_INPUT__GET_RES) {
    SStreamTrigger* pTrigger = (SStreamTrigger*)data;
    qSetMultiStreamInput(exec, pTrigger->pBlock, 1, STREAM_INPUT__DATA_BLOCK, false);
  } else if (pItem->type == STREAM_INPUT__DATA_SUBMIT) {
    ASSERT(pTask->isDataScan);
    SStreamDataSubmit* pSubmit = (SStreamDataSubmit*)data;
    qDebug("task %d %p set submit input %p %p %d", pTask->taskId, pTask, pSubmit, pSubmit->data, *pSubmit->dataRef);
    qSetStreamInput(exec, pSubmit->data, STREAM_INPUT__DATA_SUBMIT, false);
  } else if (pItem->type == STREAM_INPUT__DATA_BLOCK || pItem->type == STREAM_INPUT__DATA_RETRIEVE) {
    SStreamDataBlock* pBlock = (SStreamDataBlock*)data;
    SArray*           blocks = pBlock->blocks;
    qDebug("task %d %p set ssdata input", pTask->taskId, pTask);
    qSetMultiStreamInput(exec, blocks->pData, blocks->size, STREAM_INPUT__DATA_BLOCK, false);
  } else if (pItem->type == STREAM_INPUT__DROP) {
    // TODO exec drop
    return 0;
  }

  // exec
  while (1) {
    SSDataBlock* output = NULL;
    uint64_t     ts = 0;
    if (qExecTask(exec, &output, &ts) < 0) {
      ASSERT(false);
    }
    if (output == NULL) {
      if (pItem->type == STREAM_INPUT__DATA_RETRIEVE) {
        SSDataBlock       block = {0};
        SStreamDataBlock* pRetrieveBlock = (SStreamDataBlock*)data;
        ASSERT(taosArrayGetSize(pRetrieveBlock->blocks) == 1);
        assignOneDataBlock(&block, taosArrayGet(pRetrieveBlock->blocks, 0));
        block.info.type = STREAM_PULL_OVER;
        block.info.childId = pTask->selfChildId;
        taosArrayPush(pRes, &block);
      }
      break;
    }

    if (output->info.type == STREAM_RETRIEVE) {
      if (streamBroadcastToChildren(pTask, output) < 0) {
        // TODO
      }
      continue;
    }

    SSDataBlock block = {0};
    assignOneDataBlock(&block, output);
    block.info.childId = pTask->selfChildId;
    taosArrayPush(pRes, &block);
  }
  return 0;
}

static FORCE_INLINE int32_t streamUpdateVer(SStreamTask* pTask, SStreamDataBlock* pBlock) {
  ASSERT(pBlock->type == STREAM_INPUT__DATA_BLOCK);
  int32_t             childId = pBlock->childId;
  int64_t             ver = pBlock->sourceVer;
  SStreamChildEpInfo* pChildInfo = taosArrayGetP(pTask->childEpInfo, childId);
  pChildInfo->processedVer = ver;
  return 0;
}

static SArray* streamExecForQall(SStreamTask* pTask, SArray* pRes) {
  int32_t cnt = 0;
  void*   data = NULL;
  while (1) {
    SStreamQueueItem* qItem = streamQueueNextItem(pTask->inputQueue);
    if (qItem == NULL) {
      qDebug("stream exec over, queue empty");
      break;
    }
    if (data == NULL) {
      data = qItem;
      if (qItem->type == STREAM_INPUT__DATA_BLOCK) {
        /*streamUpdateVer(pTask, (SStreamDataBlock*)qItem);*/
      }
      streamQueueProcessSuccess(pTask->inputQueue);
    } else {
      if (streamAppendQueueItem(data, qItem) < 0) {
        streamQueueProcessFail(pTask->inputQueue);
        break;
      } else {
        cnt++;
        /*streamUpdateVer(pTask, (SStreamDataBlock*)qItem);*/
        streamQueueProcessSuccess(pTask->inputQueue);
        taosArrayDestroy(((SStreamDataBlock*)qItem)->blocks);
        taosFreeQitem(qItem);
      }
    }
  }
  if (pTask->taskStatus == TASK_STATUS__DROPPING) {
    if (data) streamFreeQitem(data);
    taosArrayDestroyEx(pRes, (FDelete)blockDataFreeRes);
    return NULL;
  }

  if (data == NULL) return pRes;

  if (pTask->execType == TASK_EXEC__NONE) {
    ASSERT(((SStreamQueueItem*)data)->type == STREAM_INPUT__DATA_BLOCK);
    streamTaskOutput(pTask, data);
    return pRes;
  }

  qDebug("stream task %d exec begin, msg batch: %d", pTask->taskId, cnt);
  streamTaskExecImpl(pTask, data, pRes);
  qDebug("stream task %d exec end", pTask->taskId);

  if (taosArrayGetSize(pRes) != 0) {
    SStreamDataBlock* qRes = taosAllocateQitem(sizeof(SStreamDataBlock), DEF_QITEM);
    if (qRes == NULL) {
      streamQueueProcessFail(pTask->inputQueue);
      taosArrayDestroy(pRes);
      return NULL;
    }
    qRes->type = STREAM_INPUT__DATA_BLOCK;
    qRes->blocks = pRes;
    if (streamTaskOutput(pTask, qRes) < 0) {
      /*streamQueueProcessFail(pTask->inputQueue);*/
      taosArrayDestroyEx(pRes, (FDelete)blockDataFreeRes);
      taosFreeQitem(qRes);
      return NULL;
    }
    if (((SStreamQueueItem*)data)->type == STREAM_INPUT__DATA_SUBMIT) {
      SStreamDataSubmit* pSubmit = (SStreamDataSubmit*)data;
      qRes->childId = pTask->selfChildId;
      qRes->sourceVer = pSubmit->ver;
    }
    /*streamQueueProcessSuccess(pTask->inputQueue);*/
    pRes = taosArrayInit(0, sizeof(SSDataBlock));
  }

  streamFreeQitem(data);
  return pRes;
}

// TODO: handle version
int32_t streamExec(SStreamTask* pTask, SMsgCb* pMsgCb) {
  SArray* pRes = taosArrayInit(0, sizeof(SSDataBlock));
  if (pRes == NULL) return -1;
  while (1) {
    int8_t execStatus =
        atomic_val_compare_exchange_8(&pTask->execStatus, TASK_EXEC_STATUS__IDLE, TASK_EXEC_STATUS__EXECUTING);
    if (execStatus == TASK_EXEC_STATUS__IDLE) {
      // first run
      qDebug("stream exec, enter exec status");
      pRes = streamExecForQall(pTask, pRes);
      if (pRes == NULL) goto FAIL;

      // set status closing
      atomic_store_8(&pTask->execStatus, TASK_EXEC_STATUS__CLOSING);

      // second run, make sure inputQ and qall are cleared
      qDebug("stream exec, enter closing status");
      pRes = streamExecForQall(pTask, pRes);
      if (pRes == NULL) goto FAIL;

      taosArrayDestroyEx(pRes, (FDelete)blockDataFreeRes);
      atomic_store_8(&pTask->execStatus, TASK_EXEC_STATUS__IDLE);
      qDebug("stream exec, return result");
      return 0;
    } else if (execStatus == TASK_EXEC_STATUS__CLOSING) {
      continue;
    } else if (execStatus == TASK_EXEC_STATUS__EXECUTING) {
      ASSERT(taosArrayGetSize(pRes) == 0);
      taosArrayDestroyEx(pRes, (FDelete)blockDataFreeRes);
      return 0;
    } else {
      ASSERT(0);
    }
  }
FAIL:
  if (pRes) taosArrayDestroy(pRes);
  if (pTask->taskStatus == TASK_STATUS__DROPPING) {
    tFreeSStreamTask(pTask);
    return 0;
  } else {
    atomic_store_8(&pTask->execStatus, TASK_EXEC_STATUS__IDLE);
    return -1;
  }
}