Insert sort the fetched files, discard any extras

CYD-Klipper/src/core/files_query.cpp

@@ -9,7 +9,7 @@
 // Always has +1 entry with a null'd name
 FILESYSTEM_FILE* last_query = NULL;
 
-FILESYSTEM_FILE* get_files(){
+FILESYSTEM_FILE* get_files(int limit){
     freeze_request_thread();
 
     if (last_query != NULL){
@@ -22,42 +22,77 @@ FILESYSTEM_FILE* get_files(){
 
         free(last_query);
     }
+
     Serial.printf("Heap space pre-file-parse: %d bytes\n", esp_get_free_heap_size());
     std::list<FILESYSTEM_FILE> files;
+
+    auto timer_request = millis();
     char buff[256] = {};
     sprintf(buff, "http://%s:%d/server/files/list", global_config.klipperHost, global_config.klipperPort);
     HTTPClient client;
     client.useHTTP10(true);
     client.begin(buff);
     int httpCode = client.GET();
-    int count = 0;
+    auto timer_parse = millis();
+
     if (httpCode == 200){
         JsonDocument doc;
         auto parseResult = deserializeJson(doc, client.getStream());
         Serial.printf("Json parse: %s\n", parseResult.c_str());
         auto result = doc["result"].as<JsonArray>();
+
         for (auto file : result){
             FILESYSTEM_FILE f = {0};
             const char* path = file["path"];
+            float modified = file["modified"];
+            auto file_iter = files.begin();
+
+            while (file_iter != files.end()){
+                if ((*file_iter).modified < modified)
+                    break;
+
+                file_iter++;
+            }
+            
+            // Little inefficient as it always allocates a string, even if it doesn't have to
             f.name = (char*)malloc(strlen(path) + 1);
             if (f.name == NULL){
                 Serial.println("Failed to allocate memory");
                 continue;
             }
             strcpy(f.name, path);
-            f.modified = file["modified"];
-            files.push_back(f);
-            count++;
-        }
-    }
+            f.modified = modified;
 
-    //Serial.printf("Found %d files\n", count);
-    files.sort([](FILESYSTEM_FILE a, FILESYSTEM_FILE b){return a.modified < b.modified;});
-    files.reverse(); // TODO: Reverse is unneeded here, we can iterate backwards
+            if (file_iter != files.end())
+                files.insert(file_iter, f);
+            else 
+                files.push_back(f);
+
+            if (files.size() > limit){
+                auto last_entry = files.back();
+
+                if (last_entry.name != NULL)
+                    free(last_entry.name);
+
+                files.pop_back();
+            }
+        }
+    }
 
     size_t size = sizeof(FILESYSTEM_FILE) * (files.size() + 1);
     FILESYSTEM_FILE* result = (FILESYSTEM_FILE*)malloc(size);
-    //Serial.printf("Allocated %d bytes\n", size);
+
+    if (result == NULL){
+        Serial.println("Failed to allocate memory");
+
+        for (auto file : files){
+            free(file.name);
+        }
+
+        unfreeze_request_thread();
+        return NULL;
+    }
+
     last_query = result;
     result[files.size()].name = NULL;
 
@@ -67,6 +102,7 @@ FILESYSTEM_FILE* get_files(){
     }
 
     Serial.printf("Heap space post-file-parse: %d bytes\n", esp_get_free_heap_size());
+    Serial.printf("Got %d files. Request took %dms, parsing took %dms\n", files.size(), timer_parse - timer_request, millis() - timer_parse);
     unfreeze_request_thread();
     return last_query;
 }

CYD-Klipper/src/core/files_query.h

@@ -19,4 +19,4 @@ typedef struct _FILESYSTEM_FILE {
     float modified;
 } FILESYSTEM_FILE;
 
-FILESYSTEM_FILE* get_files();
+FILESYSTEM_FILE* get_files(int limit);

CYD-Klipper/src/ui/panels/print_panel.cpp

@@ -95,13 +95,20 @@ void print_panel_init(lv_obj_t* panel){
     lv_obj_set_size(list, panel_width_margin, panel_height_margin);
     lv_obj_align(list, LV_ALIGN_CENTER, 0, 0);
 
-    FILESYSTEM_FILE* files = get_files();
+    FILESYSTEM_FILE* files = get_files(25);
     int count = 0;
-    while (files->name != NULL && count <= 20){
+    while (files != NULL && files->name != NULL && count <= 20){
         lv_obj_t * btn = lv_list_add_btn(list, LV_SYMBOL_FILE, files->name);
         lv_obj_add_event_cb(btn, btn_print_file_verify, LV_EVENT_CLICKED, (void*)files);
 
         files += 1;
         count++;
     }
+
+    if (count <= 0){
+        lv_obj_del(list);
+        lv_obj_t * label = lv_label_create(panel);
+        lv_label_set_text(label, "Failed to read files.");
+        lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);
+    }
 }