#pragma once

#include <boost/filesystem/path.hpp>
#include <SFML/Graphics/Texture.hpp>
#include <string>
#include <unordered_map>
#include <thread>
#include <mutex>
#include <vector>

namespace TinyProcessLib
{
    class Process;
}

namespace dchat
{
    class Gif;
    
    struct ImageByUrlResult
    {
        enum class Type
        {
            CACHED,
            DOWNLOADING,
            FAILED_DOWNLOAD
        };
        
        ImageByUrlResult() : texture(nullptr), type(Type::DOWNLOADING), isGif(false) {}
        ImageByUrlResult(sf::Texture *_texture, Type _type) : texture(_texture), type(_type), isGif(false) {}
        ImageByUrlResult(Gif *_gif, Type _type) : gif(_gif), type(_type), isGif(true) {}
        
        // @texture is null if @type is DOWNLOADING or FAILED_DOWNLOAD
        union
        {
            sf::Texture *texture;
            Gif *gif;
        };
        
        Type type;
        bool isGif;
    };
    
    class Cache
    {
    public:
        Cache();
        ~Cache();
        
        // Creates directory if it doesn't exist (recursively). Throws boost exception on failure
        static boost::filesystem::path getDchatDir();
        
        static void loadBindsFromFile();
        static void replaceBindsInFile(const std::unordered_map<std::string, std::string> &binds);
        
        // Get cached image or downloads it. 
        // Default download file limit is 12MB
        // Returns ImageByUrlResult describing texture status.
        const ImageByUrlResult getImageByUrl(const std::string &url, int downloadLimitBytes = 12582912);
    private:
        struct ImageDownloadInfo
        {
            TinyProcessLib::Process *process;
            std::string url;
        };
        
        std::thread downloadWaitThread;
        std::vector<ImageDownloadInfo> imageDownloadProcesses;
        std::vector<ImageDownloadInfo> imageDownloadProcessesQueue;
        std::mutex imageDownloadMutex;
        bool alive;
    };
}