/*
  ==============================================================================

   This file is part of the JUCE framework.
   Copyright (c) Raw Material Software Limited

   JUCE is an open source framework subject to commercial or open source
   licensing.

   By downloading, installing, or using the JUCE framework, or combining the
   JUCE framework with any other source code, object code, content or any other
   copyrightable work, you agree to the terms of the JUCE End User Licence
   Agreement, and all incorporated terms including the JUCE Privacy Policy and
   the JUCE Website Terms of Service, as applicable, which will bind you. If you
   do not agree to the terms of these agreements, we will not license the JUCE
   framework to you, and you must discontinue the installation or download
   process and cease use of the JUCE framework.

   JUCE End User Licence Agreement: https://juce.com/legal/juce-8-licence/
   JUCE Privacy Policy: https://juce.com/juce-privacy-policy
   JUCE Website Terms of Service: https://juce.com/juce-website-terms-of-service/

   Or:

   You may also use this code under the terms of the AGPLv3:
   https://www.gnu.org/licenses/agpl-3.0.en.html

   THE JUCE FRAMEWORK IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL
   WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING WARRANTY OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

namespace MidiBufferHelpers
{
    inline int getEventTime (const void* d) noexcept
    {
        return readUnaligned<int32> (d);
    }

    inline uint16 getEventDataSize (const void* d) noexcept
    {
        return readUnaligned<uint16> (static_cast<const char*> (d) + sizeof (int32));
    }

    inline uint16 getEventTotalSize (const void* d) noexcept
    {
        return (uint16) (getEventDataSize (d) + sizeof (int32) + sizeof (uint16));
    }

    static int findActualEventLength (const uint8* data, int maxBytes) noexcept
    {
        auto byte = (unsigned int) *data;

        if (byte == 0xf0 || byte == 0xf7)
        {
            int i = 1;

            while (i < maxBytes)
                if (data[i++] == 0xf7)
                    break;

            return i;
        }

        if (byte == 0xff)
        {
            if (maxBytes == 1)
                return 1;

            const auto var = MidiMessage::readVariableLengthValue (data + 1, maxBytes - 1);
            return jmin (maxBytes, var.value + 2 + var.bytesUsed);
        }

        if (byte >= 0x80)
            return jmin (maxBytes, MidiMessage::getMessageLengthFromFirstByte ((uint8) byte));

        return 0;
    }

    static uint8* findEventAfter (uint8* d, uint8* endData, int samplePosition) noexcept
    {
        while (d < endData && getEventTime (d) <= samplePosition)
            d += getEventTotalSize (d);

        return d;
    }
}

//==============================================================================
MidiBufferIterator& MidiBufferIterator::operator++() noexcept
{
    data += sizeof (int32) + sizeof (uint16) + size_t (MidiBufferHelpers::getEventDataSize (data));
    return *this;
}

MidiBufferIterator MidiBufferIterator::operator++ (int) noexcept
{
    auto copy = *this;
    ++(*this);
    return copy;
}

MidiBufferIterator::reference MidiBufferIterator::operator*() const noexcept
{
    return { data + sizeof (int32) + sizeof (uint16),
             MidiBufferHelpers::getEventDataSize (data),
             MidiBufferHelpers::getEventTime (data) };
}

//==============================================================================
MidiBuffer::MidiBuffer (const MidiMessage& message) noexcept
{
    addEvent (message, 0);
}

void MidiBuffer::swapWith (MidiBuffer& other) noexcept      { data.swapWith (other.data); }
void MidiBuffer::clear() noexcept                           { data.clearQuick(); }
void MidiBuffer::ensureSize (size_t minimumNumBytes)        { data.ensureStorageAllocated ((int) minimumNumBytes); }
bool MidiBuffer::isEmpty() const noexcept                   { return data.size() == 0; }

void MidiBuffer::clear (int startSample, int numSamples)
{
    auto start = MidiBufferHelpers::findEventAfter (data.begin(), data.end(), startSample - 1);
    auto end   = MidiBufferHelpers::findEventAfter (start,        data.end(), startSample + numSamples - 1);

    data.removeRange ((int) (start - data.begin()), (int) (end - start));
}

bool MidiBuffer::addEvent (const MidiMessage& m, int sampleNumber)
{
    return addEvent (m.getRawData(), m.getRawDataSize(), sampleNumber);
}

bool MidiBuffer::addEvent (const void* newData, int maxBytes, int sampleNumber)
{
    auto numBytes = MidiBufferHelpers::findActualEventLength (static_cast<const uint8*> (newData), maxBytes);

    if (numBytes <= 0)
        return true;

    if (std::numeric_limits<uint16>::max() < numBytes)
    {
        // This method only supports messages smaller than (1 << 16) bytes
        return false;
    }

    auto newItemSize = (size_t) numBytes + sizeof (int32) + sizeof (uint16);
    auto offset = (int) (MidiBufferHelpers::findEventAfter (data.begin(), data.end(), sampleNumber) - data.begin());

    data.insertMultiple (offset, 0, (int) newItemSize);

    auto* d = data.begin() + offset;
    writeUnaligned<int32>  (d, sampleNumber);
    d += sizeof (int32);
    writeUnaligned<uint16> (d, static_cast<uint16> (numBytes));
    d += sizeof (uint16);
    memcpy (d, newData, (size_t) numBytes);

    return true;
}

void MidiBuffer::addEvents (const MidiBuffer& otherBuffer,
                            int startSample, int numSamples, int sampleDeltaToAdd)
{
    for (auto i = otherBuffer.findNextSamplePosition (startSample); i != otherBuffer.cend(); ++i)
    {
        const auto metadata = *i;

        if (metadata.samplePosition >= startSample + numSamples && numSamples >= 0)
            break;

        addEvent (metadata.data, metadata.numBytes, metadata.samplePosition + sampleDeltaToAdd);
    }
}

int MidiBuffer::getNumEvents() const noexcept
{
    int n = 0;
    auto end = data.end();

    for (auto d = data.begin(); d < end; ++n)
        d += MidiBufferHelpers::getEventTotalSize (d);

    return n;
}

int MidiBuffer::getFirstEventTime() const noexcept
{
    return data.size() > 0 ? MidiBufferHelpers::getEventTime (data.begin()) : 0;
}

int MidiBuffer::getLastEventTime() const noexcept
{
    if (data.size() == 0)
        return 0;

    auto endData = data.end();

    for (auto d = data.begin();;)
    {
        auto nextOne = d + MidiBufferHelpers::getEventTotalSize (d);

        if (nextOne >= endData)
            return MidiBufferHelpers::getEventTime (d);

        d = nextOne;
    }
}

MidiBufferIterator MidiBuffer::findNextSamplePosition (int samplePosition) const noexcept
{
    return std::find_if (cbegin(), cend(), [&] (const MidiMessageMetadata& metadata) noexcept
    {
        return metadata.samplePosition >= samplePosition;
    });
}

//==============================================================================
JUCE_BEGIN_IGNORE_DEPRECATION_WARNINGS

MidiBuffer::Iterator::Iterator (const MidiBuffer& b) noexcept
    : buffer (b), iterator (b.data.begin())
{
}

void MidiBuffer::Iterator::setNextSamplePosition (int samplePosition) noexcept
{
    iterator = buffer.findNextSamplePosition (samplePosition);
}

bool MidiBuffer::Iterator::getNextEvent (const uint8*& midiData, int& numBytes, int& samplePosition) noexcept
{
    if (iterator == buffer.cend())
        return false;

    const auto metadata = *iterator++;
    midiData = metadata.data;
    numBytes = metadata.numBytes;
    samplePosition = metadata.samplePosition;
    return true;
}

bool MidiBuffer::Iterator::getNextEvent (MidiMessage& result, int& samplePosition) noexcept
{
    if (iterator == buffer.cend())
        return false;

    const auto metadata = *iterator++;
    result = metadata.getMessage();
    samplePosition = metadata.samplePosition;
    return true;
}

JUCE_END_IGNORE_DEPRECATION_WARNINGS

//==============================================================================
//==============================================================================
#if JUCE_UNIT_TESTS

struct MidiBufferTest final : public UnitTest
{
    MidiBufferTest()
        : UnitTest ("MidiBuffer", UnitTestCategories::midi)
    {}

    void runTest() override
    {
        beginTest ("Clear messages");
        {
            const auto message = MidiMessage::noteOn (1, 64, 0.5f);

            const auto testBuffer = [&]
            {
                MidiBuffer buffer;
                buffer.addEvent (message, 0);
                buffer.addEvent (message, 10);
                buffer.addEvent (message, 20);
                buffer.addEvent (message, 30);
                return buffer;
            }();

            {
                auto buffer = testBuffer;
                buffer.clear (10, 0);
                expectEquals (buffer.getNumEvents(), 4);
            }

            {
                auto buffer = testBuffer;
                buffer.clear (10, 1);
                expectEquals (buffer.getNumEvents(), 3);
            }

            {
                auto buffer = testBuffer;
                buffer.clear (10, 10);
                expectEquals (buffer.getNumEvents(), 3);
            }

            {
                auto buffer = testBuffer;
                buffer.clear (10, 20);
                expectEquals (buffer.getNumEvents(), 2);
            }

            {
                auto buffer = testBuffer;
                buffer.clear (10, 30);
                expectEquals (buffer.getNumEvents(), 1);
            }

            {
                auto buffer = testBuffer;
                buffer.clear (10, 300);
                expectEquals (buffer.getNumEvents(), 1);
            }
        }
    }
};

static MidiBufferTest midiBufferTest;

#endif

} // namespace juce
