/*
 * Copyright (C) 2019 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.
 */

#include "FFilamentAsset.h"

#include <gltfio/Animator.h>

#include <filament/RenderableManager.h>
#include <filament/Scene.h>

#include <utils/EntityManager.h>
#include <utils/Log.h>
#include <utils/NameComponentManager.h>

#include "Wireframe.h"

using namespace filament;
using namespace utils;

namespace filament::gltfio {

FFilamentAsset::~FFilamentAsset() {
    releaseSourceData();

    // The only things we need to free in the instances are their animators.
    // The union of all instance entities will be destroyed below.
    for (FFilamentInstance* instance : mInstances) {
        delete instance->animator;
        delete instance;
    }

    delete mAnimator;
    delete mWireframe;

    mEngine->destroy(mRoot);
    mEntityManager->destroy(mRoot);

    for (auto entity : mEntities) {
        // Destroy the entity's renderable, light, transform, and camera components.
        mEngine->destroy(entity);
        // Destroy the name component.
        if (mNameManager) {
            mNameManager->removeComponent(entity);
        }
        // Destroy the node component.
        mNodeManager->destroy(entity);
        // Destroy the actual entity.
        mEntityManager->destroy(entity);
    }
    for (auto mi : mMaterialInstances) {
        mEngine->destroy(mi);
    }
    for (auto vb : mVertexBuffers) {
        mEngine->destroy(vb);
    }
    for (auto bo : mBufferObjects) {
        mEngine->destroy(bo);
    }
    for (auto ib : mIndexBuffers) {
        mEngine->destroy(ib);
    }
    for (auto tx : mTextures) {
        mEngine->destroy(tx);
    }
    for (auto tb : mMorphTargetBuffers) {
        mEngine->destroy(tb);
    }
}

const char* FFilamentAsset::getExtras(utils::Entity entity) const noexcept {
    if (entity.isNull()) {
        return mAssetExtras.c_str();
    }
    return mNodeManager->getExtras(mNodeManager->getInstance(entity)).c_str();
}

void FFilamentAsset::createAnimators() {
    assert_invariant(mAnimator == nullptr);
    mAnimator = new Animator(this, nullptr);
    for (FFilamentInstance* instance : mInstances) {
        instance->createAnimator();
    }
}

size_t FFilamentAsset::getSkinCount() const noexcept {
    return mSkins.size();
}

const char* FFilamentAsset::getSkinNameAt(size_t skinIndex) const noexcept {
    if (mSkins.size() <= skinIndex) {
        return nullptr;
    }
    return mSkins[skinIndex].name.c_str();
}

size_t FFilamentAsset::getJointCountAt(size_t skinIndex) const noexcept {
    if (mSkins.size() <= skinIndex) {
        return 0;
    }
    return mSkins[skinIndex].joints.size();
}

const utils::Entity* FFilamentAsset::getJointsAt(size_t skinIndex) const noexcept {
    if (mSkins.size() <= skinIndex) {
        return nullptr;
    }
    return mSkins[skinIndex].joints.data();
}

void FFilamentAsset::attachSkin(size_t skinIndex, Entity target) noexcept {
    if (UTILS_UNLIKELY(mSkins.size() <= skinIndex || target.isNull())) {
        return;
    }
    mSkins[skinIndex].targets.insert(target);
}

void FFilamentAsset::detachSkin(size_t skinIndex, Entity target) noexcept {
    if (UTILS_UNLIKELY(mSkins.size() <= skinIndex || target.isNull())) {
        return;
    }
    mSkins[skinIndex].targets.erase(target);
}

const char* FFilamentAsset::getMorphTargetNameAt(utils::Entity entity,
        size_t targetIndex) const noexcept {
    if (!mResourcesLoaded) {
        return nullptr;
    }

    const auto& names =  mNodeManager->getMorphTargetNames(mNodeManager->getInstance(entity));
    if (targetIndex >= names.size()) {
        return nullptr;
    }

    return names[targetIndex].c_str();
}

size_t FFilamentAsset::getMorphTargetCountAt(utils::Entity entity) const noexcept {
    if (!mResourcesLoaded) {
        return 0;
    }

    const auto& names = mNodeManager->getMorphTargetNames(mNodeManager->getInstance(entity));
    return names.size();
}

size_t FFilamentAsset::getMaterialVariantCount() const noexcept {
    return mVariants.size();
}

const char* FFilamentAsset::getMaterialVariantName(size_t variantIndex) const noexcept {
    if (variantIndex >= mVariants.size()) {
        return nullptr;
    }
    return mVariants[variantIndex].name.c_str();
}

void FFilamentAsset::applyMaterialVariant(size_t variantIndex) noexcept {
    if (variantIndex >= mVariants.size()) {
        return;
    }
    const std::vector<VariantMapping>& mappings = mVariants[variantIndex].mappings;
    RenderableManager& rm = mEngine->getRenderableManager();
    for (const auto& mapping : mappings) {
        auto instance = rm.getInstance(mapping.renderable);
        rm.setMaterialInstanceAt(instance, mapping.primitiveIndex, mapping.material);
    }
}

Entity FFilamentAsset::getWireframe() noexcept {
    if (!mWireframe) {
        mWireframe = new Wireframe(this);
    }
    return mWireframe->mEntity;
}

void FFilamentAsset::releaseSourceData() noexcept {
    // To ensure that all possible memory is freed, we reassign to new containers rather than
    // calling clear(). With many container types (such as robin_map), clearing is a fast
    // operation that merely frees the storage for the items.
    mMatInstanceCache = {};
    mMeshCache = {};
    mResourceUris = {};
    mNodeMap = {};
    mPrimitives = {};
    mBufferSlots = {};
    mTextureSlots = {};
    mSourceAsset.reset();
    for (FFilamentInstance* instance : mInstances) {
        instance->nodeMap = {};
    }
}

const char* FFilamentAsset::getName(utils::Entity entity) const noexcept {
    if (mNameManager == nullptr) {
        return nullptr;
    }
    auto nameInstance = mNameManager->getInstance(entity);
    return nameInstance ? mNameManager->getName(nameInstance) : nullptr;
}

Entity FFilamentAsset::getFirstEntityByName(const char* name) noexcept {
    const auto iter = mNameToEntity.find(name);
    if (iter == mNameToEntity.end()) {
        return {};
    }
    return iter->front();
}

size_t FFilamentAsset::getEntitiesByName(const char* name, Entity* entities,
        size_t maxCount) const noexcept {
    const auto iter = mNameToEntity.find(name);
    if (iter == mNameToEntity.end()) {
        return 0;
    }
    const auto& source = *iter;
    if (entities == nullptr) {
        return source.size();
    }
    maxCount = std::min(maxCount, source.size());
    if (maxCount == 0) {
        return 0;
    }
    size_t count = 0;
    for (Entity entity : source) {
        entities[count] = entity;
        if (++count >= maxCount) {
            return count;
        }
    }
    return count;
}

size_t FFilamentAsset::getEntitiesByPrefix(const char* prefix, Entity* entities,
        size_t maxCount) const noexcept {
    const auto range = mNameToEntity.equal_prefix_range(prefix);
    size_t count = 0;
    for (auto iter = range.first; iter != range.second; ++iter) {
        count += iter->size();
    }
    if (entities == nullptr) {
        return count;
    }
    maxCount = std::min(maxCount, count);
    if (maxCount == 0) {
        return 0;
    }
    count = 0;
    for (auto iter = range.first; iter != range.second; ++iter) {
        const auto& source = *iter;
        for (Entity entity : source) {
            entities[count] = entity;
            if (++count >= maxCount) {
                return count;
            }
        }
    }
    return count;
}

void FFilamentAsset::addEntitiesToScene(Scene& targetScene, const Entity* entities,
        size_t count, SceneMask sceneFilter) {
    auto& nm = *mNodeManager;
    for (size_t ei = 0; ei < count; ++ei) {
        const Entity entity = entities[ei];
        NodeManager::SceneMask mask = nm.getSceneMembership(nm.getInstance(entity));
        if ((mask & sceneFilter).any()) {
            targetScene.addEntity(entity);
        }
    }
}

size_t FilamentAsset::getEntityCount() const noexcept {
    return upcast(this)->getEntityCount();
}

const Entity* FilamentAsset::getEntities() const noexcept {
    return upcast(this)->getEntities();
}

const Entity* FilamentAsset::getLightEntities() const noexcept {
    return upcast(this)->getLightEntities();
}

size_t FilamentAsset::getLightEntityCount() const noexcept {
    return upcast(this)->getLightEntityCount();
}

const Entity* FilamentAsset::getRenderableEntities() const noexcept {
    return upcast(this)->getRenderableEntities();
}

size_t FilamentAsset::getRenderableEntityCount() const noexcept {
    return upcast(this)->getRenderableEntityCount();
}

const utils::Entity* FilamentAsset::getCameraEntities() const noexcept {
    return upcast(this)->getCameraEntities();
}

size_t FilamentAsset::getCameraEntityCount() const noexcept {
    return upcast(this)->getCameraEntityCount();
}

Entity FilamentAsset::getRoot() const noexcept {
    return upcast(this)->getRoot();
}

Entity FilamentAsset::popRenderable() noexcept {
    Entity result[1];
    const bool empty = !popRenderables(result, 1);
    return empty ? Entity() : result[0];
}

size_t FilamentAsset::popRenderables(Entity* result, size_t count) noexcept {
    return upcast(this)->popRenderables(result, count);
}

size_t FilamentAsset::getMaterialInstanceCount() const noexcept {
    return upcast(this)->getMaterialInstanceCount();
}

const MaterialInstance* const* FilamentAsset::getMaterialInstances() const noexcept {
    return upcast(this)->getMaterialInstances();
}

MaterialInstance* const* FilamentAsset::getMaterialInstances() noexcept {
    return upcast(this)->getMaterialInstances();
}

size_t FilamentAsset::getResourceUriCount() const noexcept {
    return upcast(this)->getResourceUriCount();
}

const char* const* FilamentAsset::getResourceUris() const noexcept {
    return upcast(this)->getResourceUris();
}

filament::Aabb FilamentAsset::getBoundingBox() const noexcept {
    return upcast(this)->getBoundingBox();
}

const char* FilamentAsset::getName(Entity entity) const noexcept {
    return upcast(this)->getName(entity);
}

Entity FilamentAsset::getFirstEntityByName(const char* name) noexcept {
    return upcast(this)->getFirstEntityByName(name);
}

size_t FilamentAsset::getEntitiesByName(const char* name, Entity* entities,
        size_t maxCount) const noexcept {
    return upcast(this)->getEntitiesByName(name, entities, maxCount);
}

size_t FilamentAsset::getEntitiesByPrefix(const char* prefix, Entity* entities,
        size_t maxCount) const noexcept {
    return upcast(this)->getEntitiesByPrefix(prefix, entities, maxCount);
}

const char* FilamentAsset::getExtras(Entity entity) const noexcept {
    return upcast(this)->getExtras(entity);
}

Animator* FilamentAsset::getAnimator() const noexcept {
    return upcast(this)->getAnimator();
}

size_t FilamentAsset::getSkinCount() const noexcept {
    return upcast(this)->getSkinCount();
}

const char* FilamentAsset::getSkinNameAt(size_t skinIndex) const noexcept {
    return upcast(this)->getSkinNameAt(skinIndex);
}

size_t FilamentAsset::getJointCountAt(size_t skinIndex) const noexcept {
    return upcast(this)->getJointCountAt(skinIndex);
}

const utils::Entity* FilamentAsset::getJointsAt(size_t skinIndex) const noexcept {
    return upcast(this)->getJointsAt(skinIndex);
}

void FilamentAsset::attachSkin(size_t skinIndex, Entity target) noexcept {
    upcast(this)->attachSkin(skinIndex, target);
}

void FilamentAsset::detachSkin(size_t skinIndex, Entity target) noexcept {
    upcast(this)->detachSkin(skinIndex, target);
}

const char* FilamentAsset::getMorphTargetNameAt(utils::Entity entity,
        size_t targetIndex) const noexcept {
    return upcast(this)->getMorphTargetNameAt(entity, targetIndex);
}

size_t FilamentAsset::getMorphTargetCountAt(utils::Entity entity) const noexcept {
    return upcast(this)->getMorphTargetCountAt(entity);
}

const char* FilamentAsset::getMaterialVariantName(size_t variantIndex) const noexcept {
    return upcast(this)->getMaterialVariantName(variantIndex);
}

void FilamentAsset::applyMaterialVariant(size_t variantIndex) noexcept {
    return upcast(this)->applyMaterialVariant(variantIndex);
}

size_t FilamentAsset::getMaterialVariantCount() const noexcept {
    return upcast(this)->getMaterialVariantCount();
}

Entity FilamentAsset::getWireframe() noexcept {
    return upcast(this)->getWireframe();
}

Engine* FilamentAsset::getEngine() const noexcept {
    return upcast(this)->getEngine();
}

void FilamentAsset::releaseSourceData() noexcept {
    return upcast(this)->releaseSourceData();
}

const void* FilamentAsset::getSourceAsset() noexcept {
    return upcast(this)->getSourceAsset();
}

FilamentInstance** FilamentAsset::getAssetInstances() noexcept {
    return upcast(this)->getAssetInstances();
}

size_t FilamentAsset::getAssetInstanceCount() const noexcept {
    return upcast(this)->getAssetInstanceCount();
}

size_t FilamentAsset::getSceneCount() const noexcept {
    return upcast(this)->getSceneCount();
}

const char* FilamentAsset::getSceneName(size_t sceneIndex) const noexcept {
    return upcast(this)->getSceneName(sceneIndex);
}

void FilamentAsset::addEntitiesToScene(Scene& targetScene, const Entity* entities, size_t count,
        SceneMask sceneFilter) {
    upcast(this)->addEntitiesToScene(targetScene, entities, count, sceneFilter);
}

} // namespace filament::gltfio