Mercurial > hg > svcore
view data/fileio/CSVStreamWriter.h @ 1443:cdb316c6a151 streaming-csv-writer
Fix typo of old name
author | Lucas Thompson <dev@lucas.im> |
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date | Tue, 17 Apr 2018 10:03:50 +0100 |
parents | 51493540a753 |
children | 4507be815384 |
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2017 Queen Mary, University of London. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #ifndef CSV_STREAM_WRITER_H #define CSV_STREAM_WRITER_H #include "base/BaseTypes.h" #include "base/Selection.h" #include "base/ProgressReporter.h" #include "base/DataExportOptions.h" #include "data/model/Model.h" #include <QString> #include <algorithm> namespace { const auto initProgressCalculator = [](sv_frame_t nFramesToWrite) { return [nFramesToWrite](sv_frame_t nFramesWritten) { return 100 * nFramesWritten / nFramesToWrite; }; }; } // namespace namespace CSVStreamWriter { template < class OutStream, class ProgressCalculatorInit = decltype(initProgressCalculator) > bool writeInChunks(OutStream& oss, const Model& model, const Selection& extents, ProgressReporter* reporter = nullptr, QString delimiter = ",", DataExportOptions options = DataExportDefaults, const sv_frame_t blockSize = 16384, const ProgressCalculatorInit& initCalc = initProgressCalculator) { if (blockSize <= 0) return false; const auto startFrame = extents.isEmpty() ? model.getStartFrame() : extents.getStartFrame(); const auto endFrame = extents.isEmpty() ? model.getEndFrame() : extents.getEndFrame(); const auto hasValidExtents = startFrame >= 0 && endFrame > startFrame; if (!hasValidExtents) return false; const auto calculateProgress = initCalc(endFrame - startFrame); auto readPtr = startFrame; int previousPercentagePoint = 0; const auto wasCancelled = [&reporter]() { return reporter && reporter->wasCancelled(); }; while (readPtr < endFrame) { if (wasCancelled()) return false; const auto start = readPtr; const auto end = std::min(start + blockSize, endFrame); oss << model.toDelimitedDataStringSubsetWithOptions( delimiter, options, start, end ) << (end < endFrame ? "\n" : ""); const auto nFramesWritten = end - startFrame; const auto currentPercentage = calculateProgress(nFramesWritten); const bool hasIncreased = currentPercentage > previousPercentagePoint; if (hasIncreased) { if (reporter) reporter->setProgress(currentPercentage); previousPercentagePoint = currentPercentage; } readPtr = end; } return !wasCancelled(); // setProgress could process event loop } template <class OutStream> bool writeInChunks(OutStream& oss, const Model& model, ProgressReporter* reporter = nullptr, QString delimiter = ",", DataExportOptions options = DataExportDefaults, const sv_frame_t blockSize = 16384) { const Selection empty; return CSV::writeInChunks( oss, model, empty, reporter, delimiter, options, blockSize ); } } // namespace CSVStreamWriter #endif