///////////////////////////////////////////////////////////////////////

// File:        workingpartset.h

// Description: Class to hold a working set of partitions of the page

//              during construction of text/image regions.

// Author:      Ray Smith

// Created:     Tue Ocr 28 17:21:01 PDT 2008

//

// (C) Copyright 2008, Google Inc.

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

//

///////////////////////////////////////////////////////////////////////

#ifndef TESSERACT_TEXTORD_WORKINGPARSET_H_

#define TESSERACT_TEXTORD_WORKINGPARSET_H_

#include "blobbox.h"      // For TO_BLOCK_LIST and BLOCK_LIST.

#include "colpartition.h" // For ColPartition_LIST.

namespace tesseract {

// WorkingPartSet holds a working set of ColPartitions during transformation

// from the grid-based storage to regions in logical reading order, and is

// therefore only used during construction of the regions.

class WorkingPartSet : public ELIST<WorkingPartSet>::LINK {

public:

  explicit WorkingPartSet(ColPartition *column)

      : column_(column), latest_part_(nullptr), part_it_(&part_set_) {}

  // Simple accessors.

  ColPartition *column() const {

    return column_;

  }

  void set_column(ColPartition *col) {

    column_ = col;

  }

  // Add the partition to this WorkingPartSet. Partitions are generally

  // stored in the order in which they are received, but if the partition

  // has a SingletonPartner, make sure that it stays with its partner.

  void AddPartition(ColPartition *part);

  // Make blocks out of any partitions in this WorkingPartSet, and append

  // them to the end of the blocks list. bleft, tright and resolution give

  // the bounds and resolution of the source image, so that blocks can be

  // made to fit in the bounds.

  // All ColPartitions go in the used_parts list, as they need to be kept

  // around, but are no longer needed.

  void ExtractCompletedBlocks(const ICOORD &bleft, const ICOORD &tright, int resolution,

                              ColPartition_LIST *used_parts, BLOCK_LIST *blocks,

                              TO_BLOCK_LIST *to_blocks);

  // Insert the given blocks at the front of the completed_blocks_ list so

  // they can be kept in the correct reading order.

  void InsertCompletedBlocks(BLOCK_LIST *blocks, TO_BLOCK_LIST *to_blocks);

private:

  // Convert the part_set_ into blocks, starting a new block at a break

  // in partnerships, or a change in linespacing (for text).

  void MakeBlocks(const ICOORD &bleft, const ICOORD &tright, int resolution,

                  ColPartition_LIST *used_parts);

  // The column that this working set applies to. Used by the caller.

  ColPartition *column_;

  // The most recently added partition.

  ColPartition *latest_part_;

  // All the partitions in the block that is currently under construction.

  ColPartition_LIST part_set_;

  // Iteratorn on part_set_ pointing to the most recent addition.

  ColPartition_IT part_it_;

  // The blocks that have been made so far and belong before the current block.

  BLOCK_LIST completed_blocks_;

  TO_BLOCK_LIST to_blocks_;

};

ELISTIZEH(WorkingPartSet)

} // namespace tesseract.

#endif // TESSERACT_TEXTORD_WORKINGPARSET_H_