/*
 * Copyright 2012, The Android Open Source Project
 *
 * 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.
 */

//#define LOG_NDEBUG 0
#define LOG_TAG "MediaCodecList"
#include <utils/Log.h>

#include "MediaCodecListOverrides.h"

#include <binder/IServiceManager.h>

#include <media/IMediaCodecList.h>
#include <media/IMediaPlayerService.h>
#include <media/MediaCodecInfo.h>

#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/AMessage.h>
#include <media/stagefright/foundation/MediaDefs.h>
#include <media/stagefright/omx/OMXUtils.h>
#include <media/stagefright/xmlparser/MediaCodecsXmlParser.h>
#include <media/stagefright/CCodec.h>
#include <media/stagefright/Codec2InfoBuilder.h>
#include <media/stagefright/MediaCodecList.h>
#include <media/stagefright/MediaErrors.h>
#include <media/stagefright/OmxInfoBuilder.h>
#include <media/stagefright/PersistentSurface.h>

#include <sys/stat.h>
#include <utils/threads.h>

#include <cutils/properties.h>

#include <algorithm>

namespace android {

namespace {

Mutex sInitMutex;

Mutex sRemoteInitMutex;

constexpr const char* kProfilingResults =
        MediaCodecsXmlParser::defaultProfilingResultsXmlPath;

bool isProfilingNeeded() {
    int8_t value = property_get_bool("debug.stagefright.profilecodec", 0);
    if (value == 0) {
        return false;
    }

    bool profilingNeeded = true;
    FILE *resultsFile = fopen(kProfilingResults, "r");
    if (resultsFile) {
        AString currentVersion = getProfilingVersionString();
        size_t currentVersionSize = currentVersion.size();
        char *versionString = new char[currentVersionSize + 1];
        fgets(versionString, currentVersionSize + 1, resultsFile);
        if (strcmp(versionString, currentVersion.c_str()) == 0) {
            // profiling result up to date
            profilingNeeded = false;
        }
        fclose(resultsFile);
        delete[] versionString;
    }
    return profilingNeeded;
}

OmxInfoBuilder sOmxInfoBuilder{true /* allowSurfaceEncoders */};
OmxInfoBuilder sOmxNoSurfaceEncoderInfoBuilder{false /* allowSurfaceEncoders */};

Mutex sCodec2InfoBuilderMutex;
std::unique_ptr<MediaCodecListBuilderBase> sCodec2InfoBuilder;

MediaCodecListBuilderBase *GetCodec2InfoBuilder() {
    Mutex::Autolock _l(sCodec2InfoBuilderMutex);
    if (!sCodec2InfoBuilder) {
        sCodec2InfoBuilder.reset(new Codec2InfoBuilder);
    }
    return sCodec2InfoBuilder.get();
}

std::vector<MediaCodecListBuilderBase *> GetBuilders() {
    std::vector<MediaCodecListBuilderBase *> builders;
    // if plugin provides the input surface, we cannot use OMX video encoders.
    // In this case, rely on plugin to provide list of OMX codecs that are usable.
    sp<PersistentSurface> surfaceTest = CCodec::CreateInputSurface();
    if (surfaceTest == nullptr) {
        ALOGD("Allowing all OMX codecs");
        builders.push_back(&sOmxInfoBuilder);
    } else {
        ALOGD("Allowing only non-surface-encoder OMX codecs");
        builders.push_back(&sOmxNoSurfaceEncoderInfoBuilder);
    }
    builders.push_back(GetCodec2InfoBuilder());
    return builders;
}

}  // unnamed namespace

// static
sp<IMediaCodecList> MediaCodecList::sCodecList;

// static
void *MediaCodecList::profilerThreadWrapper(void * /*arg*/) {
    ALOGV("Enter profilerThreadWrapper.");
    remove(kProfilingResults);  // remove previous result so that it won't be loaded to
                                // the new MediaCodecList
    sp<MediaCodecList> codecList(new MediaCodecList(GetBuilders()));
    if (codecList->initCheck() != OK) {
        ALOGW("Failed to create a new MediaCodecList, skipping codec profiling.");
        return nullptr;
    }

    const auto& infos = codecList->mCodecInfos;
    ALOGV("Codec profiling started.");
    profileCodecs(infos, kProfilingResults);
    ALOGV("Codec profiling completed.");
    codecList = new MediaCodecList(GetBuilders());
    if (codecList->initCheck() != OK) {
        ALOGW("Failed to parse profiling results.");
        return nullptr;
    }

    {
        Mutex::Autolock autoLock(sInitMutex);
        sCodecList = codecList;
    }
    return nullptr;
}

// static
sp<IMediaCodecList> MediaCodecList::getLocalInstance() {
    Mutex::Autolock autoLock(sInitMutex);

    if (sCodecList == nullptr) {
        MediaCodecList *codecList = new MediaCodecList(GetBuilders());
        if (codecList->initCheck() == OK) {
            sCodecList = codecList;

            if (isProfilingNeeded()) {
                ALOGV("Codec profiling needed, will be run in separated thread.");
                pthread_t profiler;
                if (pthread_create(&profiler, nullptr, profilerThreadWrapper, nullptr) != 0) {
                    ALOGW("Failed to create thread for codec profiling.");
                }
            }
        } else {
            // failure to initialize may be temporary. retry on next call.
            delete codecList;
        }
    }

    return sCodecList;
}

sp<IMediaCodecList> MediaCodecList::sRemoteList;

sp<MediaCodecList::BinderDeathObserver> MediaCodecList::sBinderDeathObserver;
sp<IBinder> MediaCodecList::sMediaPlayer;  // kept since linked to death

void MediaCodecList::BinderDeathObserver::binderDied(const wp<IBinder> &who __unused) {
    Mutex::Autolock _l(sRemoteInitMutex);
    sRemoteList.clear();
    sBinderDeathObserver.clear();
}

// static
sp<IMediaCodecList> MediaCodecList::getInstance() {
    Mutex::Autolock _l(sRemoteInitMutex);
    if (sRemoteList == nullptr) {
        sMediaPlayer = defaultServiceManager()->getService(String16("media.player"));
        sp<IMediaPlayerService> service =
            interface_cast<IMediaPlayerService>(sMediaPlayer);
        if (service.get() != nullptr) {
            sRemoteList = service->getCodecList();
            if (sRemoteList != nullptr) {
                sBinderDeathObserver = new BinderDeathObserver();
                sMediaPlayer->linkToDeath(sBinderDeathObserver.get());
            }
        }
        if (sRemoteList == nullptr) {
            // if failed to get remote list, create local list
            sRemoteList = getLocalInstance();
        }
    }
    return sRemoteList;
}

MediaCodecList::MediaCodecList(std::vector<MediaCodecListBuilderBase*> builders) {
    mGlobalSettings = new AMessage();
    mCodecInfos.clear();
    MediaCodecListWriter writer;
    for (MediaCodecListBuilderBase *builder : builders) {
        if (builder == nullptr) {
            ALOGD("ignored a null builder");
            continue;
        }
        mInitCheck = builder->buildMediaCodecList(&writer);
        if (mInitCheck != OK) {
            break;
        }
    }
    writer.writeGlobalSettings(mGlobalSettings);
    writer.writeCodecInfos(&mCodecInfos);
    std::stable_sort(
            mCodecInfos.begin(),
            mCodecInfos.end(),
            [](const sp<MediaCodecInfo> &info1, const sp<MediaCodecInfo> &info2) {
                // null is lowest
                return info1 == nullptr
                        || (info2 != nullptr && info1->getRank() < info2->getRank());
            });

    // remove duplicate entries
    bool dedupe = property_get_bool("debug.stagefright.dedupe-codecs", true);
    if (dedupe) {
        std::set<std::string> codecsSeen;
        for (auto it = mCodecInfos.begin(); it != mCodecInfos.end(); ) {
            std::string codecName = (*it)->getCodecName();
            if (codecsSeen.count(codecName) == 0) {
                codecsSeen.emplace(codecName);
                it++;
            } else {
                it = mCodecInfos.erase(it);
            }
        }
    }
}

MediaCodecList::~MediaCodecList() {
}

status_t MediaCodecList::initCheck() const {
    return mInitCheck;
}

// legacy method for non-advanced codecs
ssize_t MediaCodecList::findCodecByType(
        const char *type, bool encoder, size_t startIndex) const {
    static const char *advancedFeatures[] = {
        "feature-secure-playback",
        "feature-tunneled-playback",
    };

    size_t numCodecInfos = mCodecInfos.size();
    for (; startIndex < numCodecInfos; ++startIndex) {
        const MediaCodecInfo &info = *mCodecInfos[startIndex];

        if (info.isEncoder() != encoder) {
            continue;
        }
        sp<MediaCodecInfo::Capabilities> capabilities = info.getCapabilitiesFor(type);
        if (capabilities == nullptr) {
            continue;
        }
        const sp<AMessage> &details = capabilities->getDetails();

        int32_t required;
        bool isAdvanced = false;
        for (size_t ix = 0; ix < ARRAY_SIZE(advancedFeatures); ix++) {
            if (details->findInt32(advancedFeatures[ix], &required) &&
                    required != 0) {
                isAdvanced = true;
                break;
            }
        }

        if (!isAdvanced) {
            return startIndex;
        }
    }

    return -ENOENT;
}

ssize_t MediaCodecList::findCodecByName(const char *name) const {
    Vector<AString> aliases;
    for (size_t i = 0; i < mCodecInfos.size(); ++i) {
        if (strcmp(mCodecInfos[i]->getCodecName(), name) == 0) {
            return i;
        }
        mCodecInfos[i]->getAliases(&aliases);
        for (const AString &alias : aliases) {
            if (alias == name) {
                return i;
            }
        }
    }

    return -ENOENT;
}

size_t MediaCodecList::countCodecs() const {
    return mCodecInfos.size();
}

const sp<AMessage> MediaCodecList::getGlobalSettings() const {
    return mGlobalSettings;
}

//static
bool MediaCodecList::isSoftwareCodec(const AString &componentName) {
    return componentName.startsWithIgnoreCase("OMX.google.")
            || componentName.startsWithIgnoreCase("c2.android.")
            || (!componentName.startsWithIgnoreCase("OMX.")
                    && !componentName.startsWithIgnoreCase("c2."));
}

static int compareSoftwareCodecsFirst(const AString *name1, const AString *name2) {
    // sort order 1: software codecs are first (lower)
    bool isSoftwareCodec1 = MediaCodecList::isSoftwareCodec(*name1);
    bool isSoftwareCodec2 = MediaCodecList::isSoftwareCodec(*name2);
    if (isSoftwareCodec1 != isSoftwareCodec2) {
        return isSoftwareCodec2 - isSoftwareCodec1;
    }

    // sort order 2: Codec 2.0 codecs are first (lower)
    bool isC2_1 = name1->startsWithIgnoreCase("c2.");
    bool isC2_2 = name2->startsWithIgnoreCase("c2.");
    if (isC2_1 != isC2_2) {
        return isC2_2 - isC2_1;
    }

    // sort order 3: OMX codecs are first (lower)
    bool isOMX1 = name1->startsWithIgnoreCase("OMX.");
    bool isOMX2 = name2->startsWithIgnoreCase("OMX.");
    return isOMX2 - isOMX1;
}

//static
void MediaCodecList::findMatchingCodecs(
        const char *mime, bool encoder, uint32_t flags,
        Vector<AString> *matches) {
    matches->clear();

    const sp<IMediaCodecList> list = getInstance();
    if (list == nullptr) {
        return;
    }

    size_t index = 0;
    for (;;) {
        ssize_t matchIndex =
            list->findCodecByType(mime, encoder, index);

        if (matchIndex < 0) {
            break;
        }

        index = matchIndex + 1;

        const sp<MediaCodecInfo> info = list->getCodecInfo(matchIndex);
        CHECK(info != nullptr);
        AString componentName = info->getCodecName();

        if ((flags & kHardwareCodecsOnly) && isSoftwareCodec(componentName)) {
            ALOGV("skipping SW codec '%s'", componentName.c_str());
        } else {
            matches->push(componentName);
            ALOGV("matching '%s'", componentName.c_str());
        }
    }

    if (flags & kPreferSoftwareCodecs ||
            property_get_bool("debug.stagefright.swcodec", false)) {
        matches->sort(compareSoftwareCodecsFirst);
    }
}

}  // namespace android