/*
 * synergy -- mouse and keyboard sharing utility
 * Copyright (C) 2015-2016 Symless Ltd.
 * 
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file LICENSE that should have accompanied this file.
 * 
 * This package is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "synergy/ClipboardChunk.h"

#include "synergy/ProtocolUtil.h"
#include "synergy/protocol_types.h"
#include "io/IStream.h"
#include "base/Log.h"
#include <cstring>

size_t ClipboardChunk::s_expectedSize = 0;

ClipboardChunk::ClipboardChunk(size_t size) :
    Chunk(size)
{
        m_dataSize = size - CLIPBOARD_CHUNK_META_SIZE;
}

ClipboardChunk*
ClipboardChunk::start(
                    ClipboardID id,
                    UInt32 sequence,
                    const String& size)
{
    size_t sizeLength = size.size();
    ClipboardChunk* start = new ClipboardChunk(sizeLength + CLIPBOARD_CHUNK_META_SIZE);
    char* chunk = start->m_chunk;

    chunk[0] = id;
    std::memcpy (&chunk[1], &sequence, 4);
    chunk[5] = kDataStart;
    memcpy(&chunk[6], size.c_str(), sizeLength);
    chunk[sizeLength + CLIPBOARD_CHUNK_META_SIZE - 1] = '\0';

    return start;
}

ClipboardChunk*
ClipboardChunk::data(
                    ClipboardID id,
                    UInt32 sequence,
                    const String& data)
{
    size_t dataSize = data.size();
    ClipboardChunk* chunk = new ClipboardChunk(dataSize + CLIPBOARD_CHUNK_META_SIZE);
    char* chunkData = chunk->m_chunk;

    chunkData[0] = id;
    std::memcpy (&chunkData[1], &sequence, 4);
    chunkData[5] = kDataChunk;
    memcpy(&chunkData[6], data.c_str(), dataSize);
    chunkData[dataSize + CLIPBOARD_CHUNK_META_SIZE - 1] = '\0';

    return chunk;
}

ClipboardChunk*
ClipboardChunk::end(ClipboardID id, UInt32 sequence)
{
    ClipboardChunk* end = new ClipboardChunk(CLIPBOARD_CHUNK_META_SIZE);
    char* chunk = end->m_chunk;
    
    chunk[0] = id;
    std::memcpy (&chunk[1], &sequence, 4);
    chunk[5] = kDataEnd;
    chunk[CLIPBOARD_CHUNK_META_SIZE - 1] = '\0';

    return end;
}

int
ClipboardChunk::assemble(synergy::IStream* stream,
                    String& dataCached,
                    ClipboardID& id,
                    UInt32& sequence)
{
    UInt8 mark;
    String data;

    if (!ProtocolUtil::readf(stream, kMsgDClipboard + 4, &id, &sequence, &mark, &data)) {
        return kError;
    }
    
    if (mark == kDataStart) {
        s_expectedSize = synergy::string::stringToSizeType(data);
        LOG((CLOG_DEBUG "start receiving clipboard data"));
        dataCached.clear();
        return kStart;
    }
    else if (mark == kDataChunk) {
        dataCached.append(data);
        return kNotFinish;
    }
    else if (mark == kDataEnd) {
        // validate
        if (id >= kClipboardEnd) {
            return kError;
        }
        else if (s_expectedSize != dataCached.size()) {
            LOG((CLOG_ERR "corrupted clipboard data, expected size=%d actual size=%d", s_expectedSize, dataCached.size()));
            return kError;
        }
        return kFinish;
    }

    LOG((CLOG_ERR "clipboard transmission failed: unknown error"));
    return kError;
}

void
ClipboardChunk::send(synergy::IStream* stream, void* data)
{
    ClipboardChunk* clipboardData = static_cast<ClipboardChunk*>(data);

    LOG((CLOG_DEBUG1 "sending clipboard chunk"));

    char* chunk = clipboardData->m_chunk;
    ClipboardID id = chunk[0];
    UInt32 sequence;
    std::memcpy (&sequence, &chunk[1], 4);
    UInt8 mark = chunk[5];
    String dataChunk(&chunk[6], clipboardData->m_dataSize);

    switch (mark) {
    case kDataStart:
        LOG((CLOG_DEBUG2 "sending clipboard chunk start: size=%s", dataChunk.c_str()));
        break;

    case kDataChunk:
        LOG((CLOG_DEBUG2 "sending clipboard chunk data: size=%i", dataChunk.size()));
        break;

    case kDataEnd:
        LOG((CLOG_DEBUG2 "sending clipboard finished"));
        break;
    }

    ProtocolUtil::writef(stream, kMsgDClipboard, id, sequence, mark, &dataChunk);
}
