1 files changed, 164 insertions, 0 deletions
diff --git a/src/shared/item/items.cc b/src/shared/item/items.cc
new file mode 100644
index 0000000..a5540fb
--- /dev/null
+++ b/src/shared/item/items.cc
@@ -0,0 +1,164 @@
+#include "shared/item/items.hh"
+
+namespace shared {
+namespace item {
+
+item_t make_item(const item::type_t& type,
+                 const std::uint32_t& quantity) noexcept {
+    if (type >= block::type_offset) {
+        return std::make_shared<block>(type, quantity);
+    }
+    // TODO others
+    return std::make_shared<block>(type, quantity);
+}
+
+item_t make_item(const enum shared::world::block::type& type,
+                 const std::uint32_t& quantity) noexcept {
+    return std::make_shared<block>(type, quantity);
+}
+
+item_t make_item(const proto::item& item) noexcept {
+    const auto type = item.type();
+
+    constexpr auto offset = shared::item::block::type_offset;
+    if (type >= offset) {
+        const auto block =
+            static_cast<enum shared::world::block::type>(type - offset);
+        return make_item(block, item.quantity());
+    }
+    return make_item(static_cast<item::type_t>(item.type()), item.quantity());
+}
+
+items::items(const proto::item_array& proto) noexcept {
+    const auto length = static_cast<unsigned long>(proto.items_size());
+    for (auto i = 0ul; i < length; ++i) {
+
+        const auto& item = proto.items().at(static_cast<int>(i));
+
+        const auto index = item.index();
+        this->contents[index] = make_item(item);
+    }
+}
+
+// Annoying logic because we have to add into existing first, then start
+// adding new stacks after.
+bool items::maybe_add(const item::type_t& type, const std::uint32_t& quantity,
+                      const make_item_func_t& func) noexcept {
+
+    const auto stack_size = item::get_max_stack(type);
+
+    std::uint32_t added = 0;
+    const auto get_existing =
+        std::ranges::find_if(this->contents, [&](const auto& item) {
+            if (item == nullptr) {
+                return false;
+            }
+            if (item->type != type) {
+                return false;
+            }
+            if (item->quantity >= stack_size) {
+                return false;
+            }
+            return true;
+        });
+    for (auto it = get_existing; get_existing != std::end(this->contents);
+         it = get_existing) {
+
+        const auto addition =
+            std::min(quantity - added, stack_size - (*it)->quantity);
+        (*it)->quantity += addition;
+        added += addition;
+        if (added != quantity) {
+            continue;
+        }
+
+        return true;
+    }
+
+    for (auto& item : this->contents) {
+        if (item != nullptr) {
+            continue;
+        }
+
+        const auto addition = std::min(quantity - added, stack_size);
+        item = func(type, addition);
+        added += addition;
+        if (added != quantity) {
+            continue;
+        }
+
+        return true;
+    }
+
+    return false;
+}
+
+bool items::maybe_remove(const item::type_t& type,
+                         const std::uint32_t& quantity) noexcept {
+    const auto existing_it =
+        std::ranges::find_if(this->contents, [&type](const auto& i) {
+            if (i == nullptr) {
+                return false;
+            }
+            return type == i->get_type();
+        });
+    if (existing_it == std::end(this->contents)) {
+        return false;
+    }
+
+    auto& existing = (*existing_it)->quantity;
+    if (existing > quantity) {
+        existing -= quantity;
+        return true;
+    }
+
+    if (existing == quantity) {
+        (*existing_it) = nullptr;
+        return true;
+    }
+
+    const auto diff = quantity - existing;
+    (*existing_it) = nullptr;
+    return this->maybe_remove(type, diff);
+}
+
+void items::pack(proto::item_array* const proto) const noexcept {
+    const auto items = proto->mutable_items();
+    for (auto i = 0ul; i < std::size(this->contents); ++i) {
+        const auto& item = contents[i];
+        if (item == nullptr) {
+            continue;
+        }
+
+        proto::item proto_item;
+        item->pack(&proto_item, static_cast<std::uint32_t>(i));
+        items->Add(std::move(proto_item));
+    }
+}
+
+void items::increment(const std::uint32_t& index,
+                      const make_item_func_t& func) noexcept {
+    auto& item = this->contents[index];
+    if (item == nullptr) {
+        return;
+    }
+    if (item->quantity < shared::item::item::get_max_stack(item->type)) {
+        ++item->quantity;
+        return;
+    }
+    this->maybe_add(item->type, 1, func);
+}
+
+void items::decrement(const std::uint32_t& index) noexcept {
+    auto& item = this->contents[index];
+    if (item == nullptr) {
+        return;
+    }
+    item->quantity -= 1;
+    if (item->quantity == 0) {
+        item = nullptr;
+    }
+}
+
+} // namespace item
+} // namespace shared