Introduce next abstraction level of the AudioSource API

6 files changed, 118 insertions, 82 deletions

diff --git a/plugins/soundsourcem4a/soundsourcem4a.cpp b/plugins/soundsourcem4a/soundsourcem4a.cpp
index a6b3a00308..2649ee7f07 100644
--- a/plugins/soundsourcem4a/soundsourcem4a.cpp
+++ b/plugins/soundsourcem4a/soundsourcem4a.cpp
@@ -382,32 +382,33 @@ void SoundSourceM4A::restartDecoding(MP4SampleId sampleBlockId) {
     m_sampleBuffer.reset();
 }
 
-IndexRange SoundSourceM4A::readOrSkipSampleFrames(
-        IndexRange frameIndexRange,
-        SampleBuffer::WritableSlice* pOutputBuffer) {
-    auto readableFrames =
-            adjustReadableFrameIndexRangeAndOutputBuffer(
-                    frameIndexRange, pOutputBuffer);
-    if (readableFrames.empty()) {
-        return readableFrames;
+ReadableSampleFrames SoundSourceM4A::readSampleFrames(
+        ReadMode readMode,
+        WritableSampleFrames sampleFrames) {
+    const auto writableSampleFrames =
+            clampWritableSampleFrames(readMode, sampleFrames);
+    if (writableSampleFrames.frameIndexRange().empty()) {
+        return ReadableSampleFrames(writableSampleFrames.frameIndexRange());
     }
 
-    if (m_curFrameIndex != readableFrames.start()) {
+    const SINT firstFrameIndex = writableSampleFrames.frameIndexRange().start();
+
+    if (m_curFrameIndex != firstFrameIndex) {
         // NOTE(uklotzde): Resetting the decoder near to the beginning
         // of the stream when seeking backwards produces invalid sample
         // values! As a consequence the seeking test fails.
         if ((m_curSampleBlockId != MP4_INVALID_SAMPLE_ID) &&
-                (readableFrames.start() < m_curFrameIndex) &&
-                (readableFrames.start() <= (frameIndexMin() + kNumberOfPrefetchFrames))) {
+                (firstFrameIndex < m_curFrameIndex) &&
+                (firstFrameIndex <= (frameIndexMin() + kNumberOfPrefetchFrames))) {
             // Workaround: Reset the decoder when seeking near to the beginning
             // of the stream while decoding.
             reopenDecoder();
         }
 
         MP4SampleId sampleBlockId = kSampleBlockIdMin
-                + (readableFrames.start() / m_framesPerSampleBlock);
+                + (firstFrameIndex / m_framesPerSampleBlock);
         DEBUG_ASSERT(isValidSampleBlockId(sampleBlockId));
-        if ((readableFrames.start() < m_curFrameIndex) || // seeking backwards?
+        if ((firstFrameIndex < m_curFrameIndex) || // seeking backwards?
                 !isValidSampleBlockId(m_curSampleBlockId) || // invalid seek position?
                 (sampleBlockId
                         > (m_curSampleBlockId + m_numberOfPrefetchSampleBlocks))) { // jumping forward?
@@ -426,20 +427,25 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
         }
 
         // Decoding starts before the actual target position
-        DEBUG_ASSERT(m_curFrameIndex <= readableFrames.start());
+        DEBUG_ASSERT(m_curFrameIndex <= firstFrameIndex);
         const auto precedingFrames =
-                IndexRange::between(m_curFrameIndex, readableFrames.start());
+                IndexRange::between(m_curFrameIndex, firstFrameIndex);
         if (!precedingFrames.empty()
                 && (precedingFrames != skipSampleFrames(precedingFrames))) {
             kLogger.warning()
                     << "Failed to skip preceding frames"
                     << precedingFrames;
-            return IndexRange();
+            // Abort
+            return ReadableSampleFrames(
+                    IndexRange::between(
+                            m_curFrameIndex,
+                            m_curFrameIndex));
         }
     }
-    DEBUG_ASSERT(m_curFrameIndex == readableFrames.start());
+    DEBUG_ASSERT(m_curFrameIndex == firstFrameIndex);
+
+    const SINT numberOfSamplesTotal = frames2samples(writableSampleFrames.frameIndexRange().length());
 
-    const SINT numberOfSamplesTotal = frames2samples(readableFrames.length());
     SINT numberOfSamplesRemaining = numberOfSamplesTotal;
     SINT outputSampleOffset = 0;
     while (0 < numberOfSamplesRemaining) {
@@ -448,9 +454,9 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
             // Consume previously decoded sample data
             const SampleBuffer::ReadableSlice readableSlice(
                     m_sampleBuffer.readFromHead(numberOfSamplesRemaining));
-            if (pOutputBuffer) {
+            if (readMode == ReadMode::Store) {
                 SampleUtil::copy(
-                        pOutputBuffer->data(outputSampleOffset),
+                        writableSampleFrames.sampleBuffer().data(outputSampleOffset),
                         readableSlice.data(),
                         readableSlice.size());
                 outputSampleOffset += readableSlice.size();
@@ -499,9 +505,10 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
         CSAMPLE* pDecodeBuffer; // in/out parameter
         SINT decodeBufferCapacity;
         const SINT decodeBufferCapacityMin = frames2samples(m_framesPerSampleBlock);
-        if (pOutputBuffer && (decodeBufferCapacityMin <= numberOfSamplesRemaining)) {
+        if ((readMode == ReadMode::Store) &&
+                (decodeBufferCapacityMin <= numberOfSamplesRemaining)) {
             // Decode samples directly into the output buffer
-            pDecodeBuffer = pOutputBuffer->data(outputSampleOffset);
+            pDecodeBuffer = writableSampleFrames.sampleBuffer().data(outputSampleOffset);
             decodeBufferCapacity = numberOfSamplesRemaining;
         } else {
             // Decode next sample block into temporary buffer
@@ -555,7 +562,8 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
         const SINT numberOfSamplesDecoded = decFrameInfo.samples;
         DEBUG_ASSERT(numberOfSamplesDecoded <= decodeBufferCapacity);
         SINT numberOfSamplesRead;
-        if (pOutputBuffer && (pDecodeBuffer == pOutputBuffer->data(outputSampleOffset))) {
+        if ((readMode == ReadMode::Store) &&
+                (pDecodeBuffer == writableSampleFrames.sampleBuffer().data(outputSampleOffset))) {
             // Decoded in-place
             DEBUG_ASSERT(numberOfSamplesDecoded <= numberOfSamplesRemaining);
             numberOfSamplesRead = numberOfSamplesDecoded;
@@ -572,9 +580,9 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
             const SampleBuffer::ReadableSlice readableSlice(
                     m_sampleBuffer.readFromHead(numberOfSamplesRead));
             DEBUG_ASSERT(readableSlice.size() == numberOfSamplesRead);
-            if (pOutputBuffer) {
+            if (readMode == ReadMode::Store) {
                 SampleUtil::copy(
-                        pOutputBuffer->data(outputSampleOffset),
+                        writableSampleFrames.sampleBuffer().data(outputSampleOffset),
                         readableSlice.data(),
                         readableSlice.size());
                 outputSampleOffset += numberOfSamplesRead;
@@ -590,8 +598,12 @@ IndexRange SoundSourceM4A::readOrSkipSampleFrames(
 
     DEBUG_ASSERT(isValidFrameIndex(m_curFrameIndex));
     DEBUG_ASSERT(numberOfSamplesTotal >= numberOfSamplesRemaining);
-    return readableFrames.cutFrontRange(
-            samples2frames(numberOfSamplesTotal - numberOfSamplesRemaining));
+    const SINT numberOfSamples = numberOfSamplesTotal - numberOfSamplesRemaining;
+    return ReadableSampleFrames(
+            IndexRange::forward(firstFrameIndex, samples2frames(numberOfSamples)),
+            SampleBuffer::ReadableSlice(
+                    writableSampleFrames.sampleBuffer().data(),
+                    std::min(writableSampleFrames.sampleBuffer().size(), numberOfSamples)));
 }
 
 QString SoundSourceProviderM4A::getName() const {
diff --git a/plugins/soundsourcem4a/soundsourcem4a.h b/plugins/soundsourcem4a/soundsourcem4a.h
index e8f1950967..94088b8363 100644
--- a/plugins/soundsourcem4a/soundsourcem4a.h
+++ b/plugins/soundsourcem4a/soundsourcem4a.h
@@ -24,9 +24,9 @@ public:
 
     void close() override;
 
-    IndexRange readOrSkipSampleFrames(
-            IndexRange frameIndexRange,
-            SampleBuffer::WritableSlice* pOutputBuffer) override;
+    ReadableSampleFrames readSampleFrames(
+            ReadMode readMode,
+            WritableSampleFrames sampleFrames) override;
 
 private:
     OpenResult tryOpen(const AudioSourceConfig& audioSrcCfg) override;
diff --git a/plugins/soundsourcemediafoundation/soundsourcemediafoundation.cpp b/plugins/soundsourcemediafoundation/soundsourcemediafoundation.cpp
index d69b7d3e1a..a078b8f1dd 100755
--- a/plugins/soundsourcemediafoundation/soundsourcemediafoundation.cpp
+++ b/plugins/soundsourcemediafoundation/soundsourcemediafoundation.cpp
@@ -238,26 +238,35 @@ void SoundSourceMediaFoundation::seekSampleFrame(SINT frameIndex) {
     }
 }
 
-IndexRange SoundSourceMediaFoundation::readOrSkipSampleFrames(
-        IndexRange frameIndexRange,
-        SampleBuffer::WritableSlice* pOutputBuffer) {
-    auto readableFrames =
-            adjustReadableFrameIndexRangeAndOutputBuffer(
-                    frameIndexRange, pOutputBuffer);
-    if (readableFrames.empty()) {
-        return readableFrames;
-    }
-
-    seekSampleFrame(readableFrames.start());
-    if (m_currentFrameIndex != readableFrames.start()) {
+ReadableSampleFrames SoundSourceMediaFoundation::readSampleFrames(
+        ReadMode readMode,
+        WritableSampleFrames sampleFrames) {
+    const auto writableSampleFrames =
+            clampWritableSampleFrames(readMode, sampleFrames);
+    if (writableSampleFrames.frameIndexRange().empty()) {
+        return ReadableSampleFrames(writableSampleFrames.frameIndexRange());
+    }
+
+    const SINT firstFrameIndex = writableSampleFrames.frameIndexRange().start();
+
+    seekSampleFrame(firstFrameIndex);
+    if (m_currentFrameIndex != firstFrameIndex) {
          kLogger.warning()
                 << "Failed to position reader at beginning of decoding range"
-                << readableFrames;
-         return mixxx::IndexRange(); // abort
+                << writableSampleFrames.frameIndexRange();
+         // Abort
+         return ReadableSampleFrames(
+                 mixxx::IndexRange::between(
+                         m_currentFrameIndex,
+                         m_currentFrameIndex));
     }
+    DEBUG_ASSERT(m_curFrameIndex == firstFrameIndex);
+
+    const SINT numberOfFramesTotal = writableSampleFrames.frameIndexRange().length();
 
-    SINT numberOfFramesRemaining = readableFrames.length();
-    CSAMPLE* pSampleBuffer = pOutputBuffer ? pOutputBuffer->data() : nullptr;
+    CSAMPLE* pSampleBuffer = (readMode == ReadMode::Store) ?
+            writableSampleFrames.sampleBuffer().data() : nullptr;
+    SINT numberOfFramesRemaining = numberOfFramesTotal;
     while (numberOfFramesRemaining > 0) {
         SampleBuffer::ReadableSlice readableSlice(
                 m_sampleBuffer.readFromHead(
@@ -452,7 +461,14 @@ IndexRange SoundSourceMediaFoundation::readOrSkipSampleFrames(
         }
     }
 
-    return readableFrames.cutFrontRange(readableFrames.length() - numberOfFramesRemaining);
+    DEBUG_ASSERT(isValidFrameIndex(m_curFrameIndex));
+    DEBUG_ASSERT(numberOfFramesTotal >= numberOfFramesRemaining);
+    const SINT numberOfFrames = numberOfFramesTotal - numberOfFramesRemaining;
+    return ReadableSampleFrames(
+            IndexRange::forward(firstFrameIndex, numberOfFrames),
+            SampleBuffer::ReadableSlice(
+                    writableSampleFrames.sampleBuffer().data(),
+                    std::min(writableSampleFrames.sampleBuffer().size(), frames2samples(numberOfFrames))));
 }
 
 //-------------------------------------------------------------------
diff --git a/plugins/soundsourcemediafoundation/soundsourcemediafoundation.h b/plugins/soundsourcemediafoundation/soundsourcemediafoundation.h
index 7e738a9d08..58d19934bf 100755
--- a/plugins/soundsourcemediafoundation/soundsourcemediafoundation.h
+++ b/plugins/soundsourcemediafoundation/soundsourcemediafoundation.h
@@ -57,9 +57,9 @@ public:
 
     void close() override;
 
-    IndexRange readOrSkipSampleFrames(
-            IndexRange frameIndexRange,
-            SampleBuffer::WritableSlice* pOutputBuffer) override;
+    ReadableSampleFrames readSampleFrames(
+            ReadMode readMode,
+            WritableSampleFrames sampleFrames) override;
 
 private:
     OpenResult tryOpen(const mixxx::AudioSourceConfig& audioSrcCfg) override;
diff --git a/plugins/soundsourcewv/soundsourcewv.cpp b/plugins/soundsourcewv/soundsourcewv.cpp
index c5c385773d..18e0f686e5 100644
--- a/plugins/soundsourcewv/soundsourcewv.cpp
+++ b/plugins/soundsourcewv/soundsourcewv.cpp
@@ -102,26 +102,27 @@ void SoundSourceWV::close() {
     }
 }
 
-IndexRange SoundSourceWV::readOrSkipSampleFrames(
-        IndexRange frameIndexRange,
-        SampleBuffer::WritableSlice* pOutputBuffer) {
-    auto readableFrames =
-            adjustReadableFrameIndexRangeAndOutputBuffer(
-                    frameIndexRange, pOutputBuffer);
-    if (readableFrames.empty()) {
-        return readableFrames;
+ReadableSampleFrames SoundSourceWV::readSampleFrames(
+        ReadMode readMode,
+        WritableSampleFrames sampleFrames) {
+    const auto writableSampleFrames =
+            clampWritableSampleFrames(readMode, sampleFrames);
+    if (writableSampleFrames.frameIndexRange().empty()) {
+        return ReadableSampleFrames(writableSampleFrames.frameIndexRange());
     }
 
-    if (pOutputBuffer) {
-        if (m_curFrameIndex != readableFrames.start()) {
-            if (WavpackSeekSample(m_wpc, readableFrames.start())) {
-                m_curFrameIndex = readableFrames.start();
+    const SINT firstFrameIndex = writableSampleFrames.frameIndexRange().start();
+
+    if (readMode == ReadMode::Store) {
+        if (m_curFrameIndex != firstFrameIndex) {
+            if (WavpackSeekSample(m_wpc, firstFrameIndex)) {
+                m_curFrameIndex = firstFrameIndex;
             } else {
                 kLogger.warning()
-                        << "Could not seek to frame index range"
-                        << readableFrames;
+                        << "Could not seek to first frame index"
+                        << firstFrameIndex;
                 m_curFrameIndex = WavpackGetSampleIndex(m_wpc);
-                return IndexRange();
+                return ReadableSampleFrames(IndexRange::between(m_curFrameIndex, m_curFrameIndex));
             }
         }
     } else {
@@ -131,40 +132,47 @@ IndexRange SoundSourceWV::readOrSkipSampleFrames(
         // we don't want to read samples into a temporary buffer that
         // has to be allocated we are seeking to the position after
         // the skipped samples.
-        if (m_curFrameIndex != readableFrames.end()) {
-            if (WavpackSeekSample(m_wpc, readableFrames.end())) {
-                m_curFrameIndex = readableFrames.end();
-                return readableFrames;
+        if (m_curFrameIndex != writableSampleFrames.frameIndexRange().end()) {
+            if (WavpackSeekSample(m_wpc, writableSampleFrames.frameIndexRange().end())) {
+                m_curFrameIndex = writableSampleFrames.frameIndexRange().end();
+                return ReadableSampleFrames(writableSampleFrames.frameIndexRange());
             } else {
                 kLogger.warning()
                         << "Could not skip frame index range"
-                        << readableFrames;
+                        << writableSampleFrames.frameIndexRange();
                 m_curFrameIndex = WavpackGetSampleIndex(m_wpc);
-                return IndexRange::between(m_curFrameIndex, m_curFrameIndex);
+                return ReadableSampleFrames(IndexRange::between(m_curFrameIndex, m_curFrameIndex));
             }
         }
     }
+    DEBUG_ASSERT(m_curFrameIndex == firstFrameIndex);
+    DEBUG_ASSERT(readMode == ReadMode::Store);
+
+    const SINT numberOfFramesTotal = writableSampleFrames.frameIndexRange().length();
 
-    DEBUG_ASSERT(m_curFrameIndex == readableFrames.start());
-    DEBUG_ASSERT(pOutputBuffer);
     static_assert(sizeof(CSAMPLE) == sizeof(int32_t),
             "CSAMPLE and int32_t must have the same size");
+    CSAMPLE* pOutputBuffer = writableSampleFrames.sampleBuffer().data();
     SINT unpackCount = WavpackUnpackSamples(m_wpc,
-            reinterpret_cast<int32_t*>(pOutputBuffer->data()), readableFrames.length());
+            reinterpret_cast<int32_t*>(pOutputBuffer), numberOfFramesTotal);
     DEBUG_ASSERT(unpackCount >= 0);
-    DEBUG_ASSERT(unpackCount <= readableFrames.length());
+    DEBUG_ASSERT(unpackCount <= numberOfFramesTotal);
     if (!(WavpackGetMode(m_wpc) & MODE_FLOAT)) {
         // signed integer -> float
         const SINT sampleCount = frames2samples(unpackCount);
         for (SINT i = 0; i < sampleCount; ++i) {
             const int32_t sampleValue =
-                    *reinterpret_cast<int32_t*>(pOutputBuffer->data(i));
-            *pOutputBuffer->data(i) = CSAMPLE(sampleValue) * m_sampleScaleFactor;
+                    *reinterpret_cast<int32_t*>(pOutputBuffer);
+            *pOutputBuffer++ = CSAMPLE(sampleValue) * m_sampleScaleFactor;
         }
     }
-    const auto result = IndexRange::forward(m_curFrameIndex, unpackCount);
+    const auto resultRange = IndexRange::forward(m_curFrameIndex, unpackCount);
     m_curFrameIndex += unpackCount;
-    return result;
+    return ReadableSampleFrames(
+            resultRange,
+            SampleBuffer::ReadableSlice(
+                    writableSampleFrames.sampleBuffer().data(),
+                    frames2samples(unpackCount)));
 }
 
 QString SoundSourceProviderWV::getName() const {
diff --git a/plugins/soundsourcewv/soundsourcewv.h b/plugins/soundsourcewv/soundsourcewv.h
index 295a5dc9c3..5e4640a66e 100644
--- a/plugins/soundsourcewv/soundsourcewv.h
+++ b/plugins/soundsourcewv/soundsourcewv.h
@@ -16,9 +16,9 @@ class SoundSourceWV: public SoundSourcePlugin {
 
     void close() override;
 
-    IndexRange readOrSkipSampleFrames(
-            IndexRange frameIndexRange,
-            SampleBuffer::WritableSlice* pOutputBuffer) override;
+    ReadableSampleFrames readSampleFrames(
+            ReadMode readMode,
+            WritableSampleFrames sampleFrames) override;
 
   private:
     OpenResult tryOpen(const AudioSourceConfig& audioSrcCfg) override;