feat(heap): not quite working pop

src/heap/vieter_heap.c

@@ -64,6 +64,8 @@ vieter_heap_error vieter_heap_pop(void **out, vieter_heap *heap) {
     return vieter_heap_ok;
   }
 
+  vieter_heap_tree_pop(out, heap->tree);
+
   return vieter_heap_ok;
 }
 

src/heap/vieter_heap_tree.c

@@ -152,6 +152,50 @@ vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a,
   return out;
 }
 
-vieter_heap_tree *vieter_heap_tree_pop(vieter_heap_tree *tree) {
+vieter_heap_tree *vieter_heap_tree_pop(void **out, vieter_heap_tree *tree) {
+  vieter_heap_tree *tree_before_smallest = NULL;
+  vieter_heap_tree *previous_tree = NULL;
+  vieter_heap_tree *tree_out = tree;
 
+  uint64_t smallest_key = tree->root->key;
+
+  while (tree->next != NULL) {
+    previous_tree = tree;
+    tree = tree->next;
+
+    if (tree->root->key < smallest_key) {
+      smallest_key = tree->root->key;
+      *out = tree->root->data;
+      tree_before_smallest = previous_tree;
+    }
+  }
+
+  if (tree_before_smallest != NULL) {
+    previous_tree->next = tree->next;
+  } else {
+    tree_out = tree_out->next;
+  }
+
+  if (tree->order == 0) {
+    vieter_heap_tree_free(tree);
+
+    return NULL;
+  }
+
+  uint8_t old_order = tree->order;
+
+  vieter_heap_node *node = tree->root->largest_order;
+  free(tree->root);
+
+  previous_tree = vieter_heap_tree_init(node, NULL, old_order - 1);
+
+  uint8_t i = 2;
+  while (node->next_largest_order != NULL) {
+    node = node->next_largest_order;
+    previous_tree = vieter_heap_tree_init(node, previous_tree, old_order - i);
+
+    i++;
+  }
+
+  return vieter_heap_tree_merge(tree_out, previous_tree);
 }

src/heap/vieter_heap_tree.h

@@ -33,6 +33,6 @@ vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a, vieter_heap_t
 vieter_heap_tree *vieter_heap_tree_merge_same_order(vieter_heap_tree *tree_a,
                                                     vieter_heap_tree *tree_b);
 
-vieter_heap_tree *vieter_heap_tree_pop(vieter_heap_tree *tree);
+vieter_heap_tree *vieter_heap_tree_pop(void **out, vieter_heap_tree *tree);
 
 #endif

test/heap/test_heap.c

@@ -59,7 +59,7 @@ void test_pop() {
 
     for (uint64_t i = 50; i > 0; i--) {
         vieter_heap_insert(heap, i, (void *)i);
-        TEST_SIZE(heap, (uint64_t)50 - i);
+        TEST_SIZE(heap, (uint64_t)51 - i);
 
         TEST_CHECK(vieter_heap_peek(&data, heap) == vieter_heap_ok);
         TEST_CHECK(data == (void*)i);
@@ -80,5 +80,6 @@ TEST_LIST = {
     {"init", test_init},
     {"merge same order", test_merge_same_order},
     {"insert", test_insert},
+    {"pop", test_pop},
     {NULL, NULL}
 };