1 files changed, 155 insertions, 0 deletions
diff --git a/item_list.c b/item_list.c
new file mode 100644
index 0000000..93da3e9
--- /dev/null
+++ b/item_list.c
@@ -0,0 +1,155 @@
+/*
+ * item_list.c -- Implementa las listas de objetos.
+ * Copyright (C) 2018 Juan Marín Noguera
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include <stdlib.h>
+#include "collision_type.h"
+#include "error.h"
+#include "item.h"
+#include "item_list.h"
+#include "screen.h"
+
+struct ItemNode {
+	ItemList l;
+	int n;
+};
+
+struct ItemList {
+	int len;
+	int capacity;
+	Item *elems;
+};
+
+ItemList item_list_create()
+{
+	ItemList il;
+
+	il = malloc(sizeof(struct ItemList));
+
+	if (il == NULL)
+		error_libc_exit();
+
+	il->len = 0;
+	il->capacity = 1;
+
+	il->elems = malloc(sizeof(Item));
+
+	if (il->elems == NULL)
+		error_libc_exit();
+
+	return il;
+}
+
+void item_list_free(ItemList il)
+{
+	int i;
+
+	for (i = il->len - 1; i >= 0; i--)
+		item_free(il->elems[i]);
+
+	free(il->elems);
+	free(il);
+}
+
+ItemNode item_list_begin(ItemList il)
+{
+	ItemNode in = malloc(sizeof(struct ItemNode));
+
+	if (in == NULL)
+		error_libc_exit();
+
+	in->l = il;
+	in->n = 0;
+
+	return in;
+}
+
+Item item_list_current(ItemNode in)
+{
+	return in->l->elems[in->n];
+}
+
+void item_list_advance(ItemNode in)
+{
+	in->n++;
+}
+
+void item_list_delete(ItemNode in)
+{
+	item_free(in->l->elems[in->n]);
+	in->l->elems[in->n] = in->l->elems[--in->l->len];
+
+	if (in->l->len > 0 && in->l->len * 2 <= in->l->capacity) {
+		in->l->capacity /= 2;
+		in->l->elems = realloc (in->l->elems,
+					in->l->capacity * sizeof(Item));
+
+		if (in->l->elems == NULL)
+			error_libc_exit();
+	}
+}
+
+int item_list_isend(ItemNode in)
+{
+	return in->n >= in->l->len;
+}
+
+void item_list_free_node(ItemNode in)
+{
+	free(in);
+}
+
+void item_list_append(ItemList il, Item e)
+{
+	if (il->len == il->capacity) {
+		il->capacity *= 2;
+		il->elems = realloc(il->elems, il->capacity * sizeof(Item));
+
+		if (il->elems == NULL)
+			error_libc_exit();
+	}
+
+	il->elems[il->len++] = e;
+}
+
+void item_list_update(ItemList il, int scroll, int w)
+{
+	ItemNode in = item_list_begin(il);
+	Item i;
+
+	while (!item_list_isend(in)) {
+		if (item_x(i = item_list_current(in)) < scroll + w &&
+			(item_update(i) ||
+			 item_y(i) + item_height(i) <= 0 ||
+			 item_x(i) + item_width(i) <= scroll))
+			item_list_delete(in);
+		else
+			item_list_advance(in);
+	}
+
+	item_list_free_node(in);
+}
+
+void item_list_render(Screen scr, ItemList il, int scroll)
+{
+	ItemNode in;
+
+	for (in = item_list_begin(il); !item_list_isend(in);
+			item_list_advance(in))
+		item_render(scr, item_list_current(in), scroll);
+
+	item_list_free_node(in);
+}