vibed a cached downloader for images

src/services/textureCache.cpp

@@ -0,0 +1,67 @@
+#include "services/textureCache.hpp"
+
+#include <curl/curl.h>
+#include <vector>
+
+#include "glibmm/bytes.h"
+
+namespace {
+size_t write_to_buffer(void *contents, size_t size, size_t nmemb, void *userp) {
+    auto *buffer = static_cast<std::vector<unsigned char> *>(userp);
+    auto total = size * nmemb;
+    auto *bytes = static_cast<unsigned char *>(contents);
+    buffer->insert(buffer->end(), bytes, bytes + total);
+    return total;
+}
+
+Glib::RefPtr<Gdk::Texture> download_texture_from_url(const std::string &url) {
+    if (url.empty()) {
+        return {};
+    }
+
+    CURL *curl = curl_easy_init();
+    if (!curl) {
+        return {};
+    }
+
+    std::vector<unsigned char> buffer;
+    curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
+    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
+    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_to_buffer);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
+    curl_easy_setopt(curl, CURLOPT_USERAGENT, "bar/1.0");
+
+    auto res = curl_easy_perform(curl);
+    curl_easy_cleanup(curl);
+
+    if (res != CURLE_OK || buffer.empty()) {
+        return {};
+    }
+
+    auto bytes = Glib::Bytes::create(buffer.data(), buffer.size());
+    return Gdk::Texture::create_from_bytes(bytes);
+}
+} // namespace
+
+TextureCacheService *TextureCacheService::getInstance() {
+    static TextureCacheService instance;
+    return &instance;
+}
+
+Glib::RefPtr<Gdk::Texture> TextureCacheService::getTexture(const std::string &url) {
+    if (url.empty()) {
+        return {};
+    }
+
+    auto it = cache.find(url);
+    if (it != cache.end()) {
+        return it->second;
+    }
+
+    auto texture = download_texture_from_url(url);
+    if (texture) {
+        cache.emplace(url, texture);
+    }
+
+    return texture;
+}