/*
 * Copyright 2017 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 1
#define LOG_TAG "GraphicsEnv"
#include <graphicsenv/GraphicsEnv.h>

#include <sys/prctl.h>

#include <mutex>

#include <android/dlext.h>
#include <cutils/properties.h>
#include <log/log.h>

// TODO(b/37049319) Get this from a header once one exists
extern "C" {
  android_namespace_t* android_get_exported_namespace(const char*);
  android_namespace_t* android_create_namespace(const char* name,
                                                const char* ld_library_path,
                                                const char* default_library_path,
                                                uint64_t type,
                                                const char* permitted_when_isolated_path,
                                                android_namespace_t* parent);

  enum {
     ANDROID_NAMESPACE_TYPE_ISOLATED = 1,
     ANDROID_NAMESPACE_TYPE_SHARED = 2,
  };
}

namespace android {

/*static*/ GraphicsEnv& GraphicsEnv::getInstance() {
    static GraphicsEnv env;
    return env;
}

int GraphicsEnv::getCanLoadSystemLibraries() {
    if (property_get_bool("ro.debuggable", false) && prctl(PR_GET_DUMPABLE, 0, 0, 0, 0)) {
        // Return an integer value since this crosses library boundaries
        return 1;
    }
    return 0;
}

void GraphicsEnv::setDriverPath(const std::string path) {
    if (!mDriverPath.empty()) {
        ALOGV("ignoring attempt to change driver path from '%s' to '%s'",
                mDriverPath.c_str(), path.c_str());
        return;
    }
    ALOGV("setting driver path to '%s'", path.c_str());
    mDriverPath = path;
}

void GraphicsEnv::setAngleInfo(const std::string path, const std::string appName,
                               const std::string appPref, bool developerOptIn,
                               const int rulesFd, const long rulesOffset,
                               const long rulesLength) {
    if (!mAnglePath.empty()) {
        ALOGV("ignoring attempt to change ANGLE path from '%s' to '%s'", mAnglePath.c_str(),
              path.c_str());
    } else {
        ALOGV("setting ANGLE path to '%s'", path.c_str());
        mAnglePath = path;
    }

    if (!mAngleAppName.empty()) {
        ALOGV("ignoring attempt to change ANGLE app name from '%s' to '%s'", mAngleAppName.c_str(),
              appName.c_str());
    } else {
        ALOGV("setting ANGLE app name to '%s'", appName.c_str());
        mAngleAppName = appName;
    }

    if (!mAngleAppPref.empty()) {
        ALOGV("ignoring attempt to change ANGLE application opt-in from '%s' to '%s'",
              mAngleAppPref.c_str(), appPref.c_str());
    } else {
        ALOGV("setting ANGLE application opt-in to '%s'", appPref.c_str());
        mAngleAppPref = appPref;
    }

    mAngleDeveloperOptIn = developerOptIn;

    ALOGV("setting ANGLE rules file descriptor to '%i'", rulesFd);
    mAngleRulesFd = rulesFd;
    ALOGV("setting ANGLE rules offset to '%li'", rulesOffset);
    mAngleRulesOffset = rulesOffset;
    ALOGV("setting ANGLE rules length to '%li'", rulesLength);
    mAngleRulesLength = rulesLength;
}

void GraphicsEnv::setLayerPaths(NativeLoaderNamespace* appNamespace, const std::string layerPaths) {
    if (mLayerPaths.empty()) {
        mLayerPaths = layerPaths;
        mAppNamespace = appNamespace;
    } else {
        ALOGV("Vulkan layer search path already set, not clobbering with '%s' for namespace %p'",
                layerPaths.c_str(), appNamespace);
    }
}

NativeLoaderNamespace* GraphicsEnv::getAppNamespace() {
    return mAppNamespace;
}

const char* GraphicsEnv::getAngleAppName() {
    if (mAngleAppName.empty()) return nullptr;
    return mAngleAppName.c_str();
}

bool GraphicsEnv::getAngleDeveloperOptIn() {
    return mAngleDeveloperOptIn;
}

const char* GraphicsEnv::getAngleAppPref() {
    if (mAngleAppPref.empty()) return nullptr;
    return mAngleAppPref.c_str();
}

int GraphicsEnv::getAngleRulesFd() {
    return mAngleRulesFd;
}

long GraphicsEnv::getAngleRulesOffset() {
    return mAngleRulesOffset;
}

long GraphicsEnv::getAngleRulesLength() {
    return mAngleRulesLength;
}

const std::string GraphicsEnv::getLayerPaths(){
    return mLayerPaths;
}

const std::string GraphicsEnv::getDebugLayers() {
    return mDebugLayers;
}

void GraphicsEnv::setDebugLayers(const std::string layers) {
    mDebugLayers = layers;
}

android_namespace_t* GraphicsEnv::getDriverNamespace() {
    static std::once_flag once;
    std::call_once(once, [this]() {
        if (mDriverPath.empty())
            return;
        // If the sphal namespace isn't configured for a device, don't support updatable drivers.
        // We need a parent namespace to inherit the default search path from.
        auto sphalNamespace = android_get_exported_namespace("sphal");
        if (!sphalNamespace) return;
        mDriverNamespace = android_create_namespace("gfx driver",
                                                    mDriverPath.c_str(), // ld_library_path
                                                    mDriverPath.c_str(), // default_library_path
                                                    ANDROID_NAMESPACE_TYPE_SHARED |
                                                            ANDROID_NAMESPACE_TYPE_ISOLATED,
                                                    nullptr, // permitted_when_isolated_path
                                                    sphalNamespace);
    });
    return mDriverNamespace;
}

android_namespace_t* GraphicsEnv::getAngleNamespace() {
    static std::once_flag once;
    std::call_once(once, [this]() {
        if (mAnglePath.empty()) return;

        mAngleNamespace = android_create_namespace("ANGLE",
                                                   nullptr,            // ld_library_path
                                                   mAnglePath.c_str(), // default_library_path
                                                   ANDROID_NAMESPACE_TYPE_SHARED |
                                                           ANDROID_NAMESPACE_TYPE_ISOLATED,
                                                   nullptr, // permitted_when_isolated_path
                                                   nullptr);
        if (!mAngleNamespace) ALOGD("Could not create ANGLE namespace from default");
    });

    return mAngleNamespace;
}

} // namespace android

extern "C" {
android_namespace_t* android_getDriverNamespace() {
    return android::GraphicsEnv::getInstance().getDriverNamespace();
}
android_namespace_t* android_getAngleNamespace() {
    return android::GraphicsEnv::getInstance().getAngleNamespace();
}
const char* android_getAngleAppName() {
    return android::GraphicsEnv::getInstance().getAngleAppName();
}
bool android_getAngleDeveloperOptIn() {
    return android::GraphicsEnv::getInstance().getAngleDeveloperOptIn();
}
const char* android_getAngleAppPref() {
    return android::GraphicsEnv::getInstance().getAngleAppPref();
}
int android_getAngleRulesFd() {
   return android::GraphicsEnv::getInstance().getAngleRulesFd();
}
long android_getAngleRulesOffset() {
   return android::GraphicsEnv::getInstance().getAngleRulesOffset();
}
long android_getAngleRulesLength() {
   return android::GraphicsEnv::getInstance().getAngleRulesLength();
}
const char* android_getLayerPaths() {
    return android::GraphicsEnv::getInstance().getLayerPaths().c_str();
}
const char* android_getDebugLayers() {
    return android::GraphicsEnv::getInstance().getDebugLayers().c_str();
}
}