getOrSyncHistoryMessages method

void getOrSyncHistoryMessages(String channelId, int channelType, int oldestOrderSeq, bool contain, int pullMode, int limit, dynamic iGetOrSyncHistoryMsgBack(List<WKMsg>), dynamic syncBack(),)

Implementation

void getOrSyncHistoryMessages(
    String channelId,
    int channelType,
    int oldestOrderSeq,
    bool contain,
    int pullMode,
    int limit,
    final Function(List<WKMsg>) iGetOrSyncHistoryMsgBack,
    final Function() syncBack) async {
  //获取原始数据
  List<WKMsg> list = await getMessages(
      channelId, channelType, oldestOrderSeq, contain, pullMode, limit);
  //业务判断数据
  List<WKMsg> tempList = [];
  for (int i = 0, size = list.length; i < size; i++) {
    tempList.add(list[i]);
  }

  //先通过message_seq排序
  if (tempList.isNotEmpty) {
    tempList.sort((a, b) => a.messageSeq.compareTo(b.messageSeq));
  }
  //获取最大和最小messageSeq
  int minMessageSeq = 0;
  int maxMessageSeq = 0;
  for (int i = 0, size = tempList.length; i < size; i++) {
    if (tempList[i].messageSeq != 0) {
      if (minMessageSeq == 0) minMessageSeq = tempList[i].messageSeq;
      if (tempList[i].messageSeq > maxMessageSeq) {
        maxMessageSeq = tempList[i].messageSeq;
      }

      if (tempList[i].messageSeq < minMessageSeq) {
        minMessageSeq = tempList[i].messageSeq;
      }
    }
  }
  //是否同步消息
  bool isSyncMsg = false;
  int startMsgSeq = 0;
  int endMsgSeq = 0;
  //判断页与页之间是否连续
  int oldestMsgSeq;

  //如果获取到的messageSeq为0说明oldestOrderSeq这条消息是本地消息则获取他上一条或下一条消息的messageSeq做为判断
  if (oldestOrderSeq % 1000 != 0) {
    oldestMsgSeq =
        await getMsgSeq(channelId, channelType, oldestOrderSeq, pullMode);
  } else {
    oldestMsgSeq = oldestOrderSeq ~/ 1000;
  }

  if (pullMode == 0) {
    //下拉获取消息
    if (oldestMsgSeq == 1) {
      iGetOrSyncHistoryMsgBack([]);
      return;
    }
    if (maxMessageSeq != 0 &&
        oldestMsgSeq != 0 &&
        oldestMsgSeq - maxMessageSeq > 1) {
      isSyncMsg = true;
      if (contain) {
        startMsgSeq = oldestMsgSeq;
      } else {
        startMsgSeq = oldestMsgSeq - 1;
      }
      endMsgSeq = maxMessageSeq;
    }
  } else {
    //上拉获取消息
    if (minMessageSeq != 0 &&
        oldestMsgSeq != 0 &&
        minMessageSeq - oldestMsgSeq > 1) {
      isSyncMsg = true;
      if (contain) {
        startMsgSeq = oldestMsgSeq;
      } else {
        startMsgSeq = oldestMsgSeq + 1;
      }
      endMsgSeq = minMessageSeq;
    }
  }
  if (!isSyncMsg) {
    //判断当前页是否连续
    for (int i = 0, size = tempList.length; i < size; i++) {
      int nextIndex = i + 1;
      if (nextIndex < tempList.length) {
        if (tempList[nextIndex].messageSeq != 0 &&
            tempList[i].messageSeq != 0 &&
            tempList[nextIndex].messageSeq - tempList[i].messageSeq > 1) {
          //判断该条消息是否被删除
          int num = await getDeletedCount(tempList[i].messageSeq,
              tempList[nextIndex].messageSeq, channelId, channelType);
          if (num <
              (tempList[nextIndex].messageSeq - tempList[i].messageSeq) - 1) {
            isSyncMsg = true;
            int max = tempList[nextIndex].messageSeq;
            int min = tempList[i].messageSeq;
            if (tempList[nextIndex].messageSeq < tempList[i].messageSeq) {
              max = tempList[i].messageSeq;
              min = tempList[nextIndex].messageSeq;
            }
            if (pullMode == 0) {
              // 下拉
              if (max > startMsgSeq) {
                startMsgSeq = max;
              }
              if (endMsgSeq == 0 || min < endMsgSeq) {
                endMsgSeq = min;
              }
            } else {
              if (startMsgSeq == 0 || min < startMsgSeq) {
                startMsgSeq = min;
              }
              if (max > endMsgSeq) {
                endMsgSeq = max;
              }
            }
          }
        }
      }
    }
  }
  if (!isSyncMsg) {
    if (minMessageSeq == 1) {
      requestCount = 0;
      iGetOrSyncHistoryMsgBack(list);
      return;
    }
  }
  //计算最后一页后是否还存在消息
  int syncLimit = limit;
  if (!isSyncMsg && tempList.length < limit) {
    isSyncMsg = true;
    if (contain) {
      startMsgSeq = oldestMsgSeq;
    } else {
      if (pullMode == 0) {
        startMsgSeq = oldestMsgSeq - 1;
      } else {
        startMsgSeq = oldestMsgSeq + 1;
      }
    }
    endMsgSeq = 0;
  }
  if (startMsgSeq == 0 && endMsgSeq == 0 && tempList.length < limit) {
    isSyncMsg = true;
    endMsgSeq = oldestMsgSeq;
    startMsgSeq = 0;
  }
  if (isSyncMsg &&
      (startMsgSeq != endMsgSeq || (startMsgSeq == 0 && endMsgSeq == 0)) &&
      requestCount < 5) {
    if (requestCount == 0) {
      syncBack();
    }
    //同步消息
    requestCount++;
    WKIM.shared.messageManager.setSyncChannelMsgListener(
        channelId, channelType, startMsgSeq, endMsgSeq, syncLimit, pullMode,
        (syncChannelMsg) {
      if (syncChannelMsg != null) {
        if (oldestMsgSeq == 0 ||
            (syncChannelMsg.messages != null &&
                syncChannelMsg.messages!.length < limit)) {
          requestCount = 5;
        }
        getOrSyncHistoryMessages(channelId, channelType, oldestOrderSeq,
            contain, pullMode, limit, iGetOrSyncHistoryMsgBack, syncBack);
      } else {
        requestCount = 0;
        iGetOrSyncHistoryMsgBack(list);
      }
    });
  } else {
    requestCount = 0;
    iGetOrSyncHistoryMsgBack(list);
  }
}