/****************************************************************************
 Copyright (c) 2013 cocos2d-x.org
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.

 https://axmolengine.github.io/

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/

#ifndef __Manifest__
#define __Manifest__

#include <string>
#include <unordered_map>
#include <vector>

#include "extensions/ExtensionMacros.h"
#include "extensions/ExtensionExport.h"
#include "network/Downloader.h"
#include "platform/FileUtils.h"

#include "rapidjson/document-wrapper.h"

NS_AX_EXT_BEGIN

struct DownloadUnit
{
    std::string srcUrl;
    std::string storagePath;
    std::string customId;
    float size;
};

struct ManifestAsset
{
    std::string md5;
    std::string path;
    bool compressed;
    float size;
    int downloadState;
};

typedef hlookup::string_map<DownloadUnit> DownloadUnits;

class AX_EX_DLL Manifest : public Ref
{
public:
    friend class AssetsManagerEx;

    //! The type of difference
    enum class DiffType
    {
        ADDED,
        DELETED,
        MODIFIED
    };

    enum DownloadState
    {
        UNSTARTED,
        DOWNLOADING,
        SUCCESSED,
        UNMARKED
    };

    //! Asset object
    typedef ManifestAsset Asset;

    //! Object indicate the difference between two Assets
    struct AssetDiff
    {
        Asset asset;
        DiffType type;
    };

    /** @brief Check whether the version informations have been fully loaded
     */
    bool isVersionLoaded() const;

    /** @brief Check whether the manifest have been fully loaded
     */
    bool isLoaded() const;

    /** @brief Gets remote package url.
     */
    std::string_view getPackageUrl() const;

    /** @brief Gets remote manifest file url.
     */
    std::string_view getManifestFileUrl() const;

    /** @brief Gets remote version file url.
     */
    std::string_view getVersionFileUrl() const;

    /** @brief Gets manifest version.
     */
    std::string_view getVersion() const;

    /** @brief Get the search paths list related to the Manifest.
     */
    std::vector<std::string> getSearchPaths() const;

protected:
    /** @brief Constructor for Manifest class
     * @param manifestUrl Url of the local manifest
     */
    Manifest(std::string_view manifestUrl = "");

    /** @brief Load the json file into local json object
     * @param url Url of the json file
     */
    void loadJson(std::string_view url);

    /** @brief Parse the version file information into this manifest
     * @param versionUrl Url of the local version file
     */
    void parseVersion(std::string_view versionUrl);

    /** @brief Parse the manifest file information into this manifest
     * @param manifestUrl Url of the local manifest
     */
    void parse(std::string_view manifestUrl);

    /** @brief Check whether the version of this manifest equals to another.
     * @param b   The other manifest
     * @return Equal or not
     */
    bool versionEquals(const Manifest* b) const;

    /** @brief Check whether the version of this manifest is greater than another.
     * @param b         The other manifest
     * @param [handle]  Customized comparasion handle function
     * @return Greater or not
     */
    bool versionGreater(const Manifest* b,
                        const std::function<int(std::string_view versionA, std::string_view versionB)>& handle) const;

    /** @brief Generate difference between this Manifest and another.
     * @param b   The other manifest
     */
    hlookup::string_map<AssetDiff> genDiff(const Manifest* b) const;

    /** @brief Generate resuming download assets list
     * @param units   The download units reference to be modified by the generation result
     */
    void genResumeAssetsList(DownloadUnits* units) const;

    /** @brief Prepend all search paths to the FileUtils.
     */
    void prependSearchPaths();

    void loadVersion(const rapidjson::Document& json);

    void loadManifest(const rapidjson::Document& json);

    void saveToFile(std::string_view filepath);

    Asset parseAsset(std::string_view path, const rapidjson::Value& json);

    void clear();

    /** @brief Gets all groups.
     */
    const std::vector<std::string>& getGroups() const;

    /** @brief Gets all groups version.
     */
    const hlookup::string_map<std::string>& getGroupVerions() const;

    /** @brief Gets version for the given group.
     * @param group   Key of the requested group
     */
    std::string_view getGroupVersion(std::string_view group) const;

    /**
     * @brief Gets assets.
     * @lua NA
     */
    const hlookup::string_map<Asset>& getAssets() const;

    /** @brief Set the download state for an asset
     * @param key   Key of the asset to set
     * @param state The current download state of the asset
     */
    void setAssetDownloadState(std::string_view key, const DownloadState& state);

    void setManifestRoot(std::string_view root) { _manifestRoot = root; };

private:
    //! Indicate whether the version informations have been fully loaded
    bool _versionLoaded;

    //! Indicate whether the manifest have been fully loaded
    bool _loaded;

    //! Reference to the global file utils
    FileUtils* _fileUtils;

    //! The local manifest root
    std::string _manifestRoot;

    //! The remote package url
    std::string _packageUrl;

    //! The remote path of manifest file
    std::string _remoteManifestUrl;

    //! The remote path of version file [Optional]
    std::string _remoteVersionUrl;

    //! The version of local manifest
    std::string _version;

    //! All groups exist in manifest [Optional]
    std::vector<std::string> _groups;

    //! The versions of all local group [Optional]
    hlookup::string_map<std::string> _groupVer;

    //! The version of local engine
    std::string _engineVer;

    //! Full assets list
    hlookup::string_map<Asset> _assets;

    //! All search paths
    std::vector<std::string> _searchPaths;

    rapidjson::Document _json;
};

NS_AX_EXT_END
#endif /* defined(__Manifest__) */