Added rate limiting and settings fixes.

src/Routes/Images.c

@@ -1,10 +1,21 @@
 #include "Images.h"
+#include "../Cache/Cache.h"
+#include "../Limiter/RateLimit.h"
 #include "../Scraping/ImageScraping.h"
 #include "../Utility/Unescape.h"
 #include "../Utility/Utility.h"
 #include "Config.h"
 
+static char *build_images_request_cache_key(const char *query, int page,
+                                            const char *client_key) {
+  char scope_key[BUFFER_SIZE_MEDIUM];
+  snprintf(scope_key, sizeof(scope_key), "images_request:%s",
+           client_key ? client_key : "unknown");
+  return cache_compute_key(query, page, scope_key);
+}
+
 int images_handler(UrlParams *params) {
+  extern Config global_config;
   TemplateContext ctx = new_context();
   char *raw_query = "";
   int page = 1;
@@ -52,12 +63,55 @@ int images_handler(UrlParams *params) {
     return -1;
   }
 
+  char client_key[BUFFER_SIZE_SMALL];
+  rate_limit_get_client_key(client_key, sizeof(client_key));
+
+  char *request_cache_key =
+      build_images_request_cache_key(raw_query, page, client_key);
+  int request_is_cached = 0;
+
+  if (request_cache_key && get_cache_ttl_image() > 0) {
+    char *cached_marker = NULL;
+    size_t cached_marker_size = 0;
+
+    if (cache_get(request_cache_key, (time_t)get_cache_ttl_image(),
+                  &cached_marker, &cached_marker_size) == 0) {
+      request_is_cached = 1;
+    }
+
+    free(cached_marker);
+  }
+
+  if (!request_is_cached) {
+    RateLimitConfig rate_limit_config = {
+        .max_requests = global_config.rate_limit_images_requests,
+        .interval_seconds = global_config.rate_limit_images_interval,
+    };
+    RateLimitResult rate_limit_result =
+        rate_limit_check("images", &rate_limit_config);
+    if (rate_limit_result.limited) {
+      char response[256];
+      snprintf(response, sizeof(response),
+               "<h1>Slow down!</h1><p>Too many image searches from you!</p>");
+      send_response(response);
+      free(request_cache_key);
+      free(display_query);
+      free_context(&ctx);
+      return -1;
+    }
+
+    if (request_cache_key && get_cache_ttl_image() > 0) {
+      cache_set(request_cache_key, "1", 1);
+    }
+  }
+
   ImageResult *results = NULL;
   int result_count = 0;
 
   if (scrape_images(raw_query, page, &results, &result_count) != 0 ||
       !results) {
     send_response("<h1>Error fetching images</h1>");
+    free(request_cache_key);
     free(display_query);
     free_context(&ctx);
     return -1;
@@ -72,6 +126,7 @@ int images_handler(UrlParams *params) {
     if (inner_counts)
       free(inner_counts);
     free_image_results(results, result_count);
+    free(request_cache_key);
     free(display_query);
     free_context(&ctx);
     return -1;
@@ -106,6 +161,7 @@ int images_handler(UrlParams *params) {
   free(inner_counts);
 
   free_image_results(results, result_count);
+  free(request_cache_key);
   free(display_query);
   free_context(&ctx);