feat: state manager

1 files changed, 82 insertions, 0 deletions

diff --git a/src/core/state_manager.cpp b/src/core/state_manager.cpp
new file mode 100644
index 0000000..5da601c
--- /dev/null
+++ b/src/core/state_manager.cpp
@@ -0,0 +1,82 @@
+#include "state_manager.h"
+#include "log.h"
+
+namespace Donut
+{
+    void StateManager::shutdown()
+    {
+        if (m_current_state)
+            m_current_state->on_exit();
+            
+        destroy_states();
+        DONUT_INFO("StateManager shutdown");
+    }
+
+    void StateManager::destroy_states()
+    {
+        m_states.clear();
+        m_current_state = nullptr;
+        m_current_state_name = "";
+    }
+
+    void StateManager::register_state(const std::string& state_name, std::unique_ptr<State> state)
+    {
+        if (m_states.find(state_name) != m_states.end())
+            DONUT_WARN("State '{}' already exists, overwriting", state_name);
+        m_states[state_name] = std::move(state);
+        DONUT_INFO("Registered state: {}", state_name);
+    }
+
+    void StateManager::switch_to_state(const std::string& state_name)
+    {
+        auto it = m_states.find(state_name);
+        if (it == m_states.end())
+        {
+            DONUT_ERROR("Attempted to switch to unknown state: {}", state_name);
+            return;
+        }
+
+        State* new_state = it->second.get();
+        if (new_state == m_current_state)
+            return;
+
+        if (m_current_state)
+            m_current_state->on_exit();
+
+        m_current_state = new_state;
+        m_current_state_name = state_name;
+        m_current_state->on_enter();
+        DONUT_INFO("Switched to state: {}", state_name);
+    }
+
+    State* StateManager::get_state(const std::string& state_name)
+    {
+        auto it = m_states.find(state_name);
+        if (it != m_states.end())
+            return it->second.get();
+        return nullptr;
+    }
+
+    bool StateManager::has_state(const std::string& state_name) const
+    {
+        return m_states.find(state_name) != m_states.end();
+    }
+
+    void StateManager::update(float delta_time)
+    {
+        if (m_current_state)
+            m_current_state->on_update(delta_time);
+    }
+
+    void StateManager::render()
+    {
+        if (m_current_state)
+            m_current_state->on_render();
+    }
+
+    void StateManager::on_event(Event& event)
+    {
+        if (m_current_state)
+            m_current_state->on_event(event);
+    }
+}