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#pragma once
#include "../include/Storage.hpp"
#include "../include/MessageQueue.hpp"
#include "../include/FileAnalyzer.hpp"
#include "../include/AsyncTask.hpp"
#include <SFML/System/Vector2.hpp>
#include <SFML/Graphics/Texture.hpp>
#include <SFML/System/Clock.hpp>
#include <string>
#include <memory>
#include <unordered_map>
namespace QuickMedia {
enum class LoadingState {
NOT_LOADED,
LOADING,
FINISHED_LOADING,
APPLIED_TO_TEXTURE
};
struct ThumbnailData {
LoadingState loading_state = LoadingState::NOT_LOADED;
sf::Texture texture;
std::unique_ptr<sf::Image> image; // Set in another thread. This should be .reset after loading it into |texture|, to save memory
size_t counter = 0;
};
// This function is async
bool create_thumbnail(const Path &thumbnail_path, const Path &thumbnail_path_resized, sf::Vector2i resize_target_size, ContentType content_type);
constexpr int NUM_IMAGE_LOAD_THREADS = 4;
class AsyncImageLoader {
public:
static AsyncImageLoader& get_instance();
// Never returns nullptr. Instead check the |loading_state| of the thumbnail data to see if it has finished loading.
// This function should be called every frame for the objects that need to display this thumbnail, otherwise it can be unloaded.
// set |resize_target_size| to {0, 0} to disable resizing.
// Note: this method is not thread-safe
std::shared_ptr<ThumbnailData> get_thumbnail(const std::string &url, bool local, sf::Vector2i resize_target_size);
// Note: this should only be called once every frame.
// Note: this method is not thread-safe
void update();
private:
AsyncImageLoader();
~AsyncImageLoader();
AsyncImageLoader(AsyncImageLoader &other) = delete;
AsyncImageLoader& operator=(AsyncImageLoader &other) = delete;
struct ThumbnailLoadData {
Path path;
Path thumbnail_path;
bool local;
std::shared_ptr<ThumbnailData> thumbnail_data;
sf::Vector2i resize_target_size;
};
// set |resize_target_size| to {0, 0} to disable resizing.
// Note: this method is not thread-safe
void load_thumbnail(const std::string &url, bool local, sf::Vector2i resize_target_size, std::shared_ptr<ThumbnailData> thumbnail_data);
// Returns -1 if all threads are busy
int get_free_load_index() const;
private:
bool loading_image[NUM_IMAGE_LOAD_THREADS];
// TODO: Use curl single-threaded multi-download feature instead
AsyncTask<void> download_image_thread[NUM_IMAGE_LOAD_THREADS];
AsyncTask<void> load_image_thread;
MessageQueue<ThumbnailLoadData> image_load_queue;
std::unordered_map<std::string, std::shared_ptr<ThumbnailData>> thumbnails;
size_t counter = 0;
};
}
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