Centralize legacy app startup

src/app_core/app_startup.h

@@ -0,0 +1,112 @@
+#pragma once
+
+#include "foundation/result.h"
+
+#include <limits>
+
+namespace pp::app {
+
+struct AppStartupPlan {
+    int previous_run_counter = 0;
+    int next_run_counter = 1;
+    bool save_preferences = true;
+    bool start_timelapse = false;
+    bool vr_controllers_enabled = true;
+    bool show_license_warning = false;
+};
+
+class AppStartupServices {
+public:
+    virtual ~AppStartupServices() = default;
+
+    virtual void store_run_counter(int value) = 0;
+    virtual void save_preferences() = 0;
+    virtual void start_timelapse_recording() = 0;
+    virtual void apply_vr_controllers_enabled(bool enabled) = 0;
+    virtual void show_license_warning() = 0;
+};
+
+[[nodiscard]] inline pp::foundation::Result<AppStartupPlan> plan_app_startup(
+    int current_run_counter,
+    bool auto_timelapse_enabled,
+    bool stored_vr_controllers_enabled,
+    bool license_valid)
+{
+    if (current_run_counter < 0) {
+        return pp::foundation::Result<AppStartupPlan>::failure(
+            pp::foundation::Status::invalid_argument("run counter must not be negative"));
+    }
+
+    if (current_run_counter == std::numeric_limits<int>::max()) {
+        return pp::foundation::Result<AppStartupPlan>::failure(
+            pp::foundation::Status::out_of_range("run counter would overflow"));
+    }
+
+    AppStartupPlan plan;
+    plan.previous_run_counter = current_run_counter;
+    plan.next_run_counter = current_run_counter + 1;
+    plan.start_timelapse = auto_timelapse_enabled;
+    plan.vr_controllers_enabled = stored_vr_controllers_enabled;
+    plan.show_license_warning = !license_valid;
+    return pp::foundation::Result<AppStartupPlan>::success(plan);
+}
+
+[[nodiscard]] inline pp::foundation::Status execute_app_startup_plan(
+    const AppStartupPlan& plan,
+    AppStartupServices& services)
+{
+    if (plan.previous_run_counter < 0 || plan.next_run_counter <= plan.previous_run_counter) {
+        return pp::foundation::Status::invalid_argument("startup plan has invalid run counter state");
+    }
+
+    services.store_run_counter(plan.next_run_counter);
+    if (plan.save_preferences) {
+        services.save_preferences();
+    }
+    if (plan.start_timelapse) {
+        services.start_timelapse_recording();
+    }
+    services.apply_vr_controllers_enabled(plan.vr_controllers_enabled);
+    if (plan.show_license_warning) {
+        services.show_license_warning();
+    }
+
+    return pp::foundation::Status::success();
+}
+
+[[nodiscard]] inline pp::foundation::Status execute_app_startup_persistence_plan(
+    const AppStartupPlan& plan,
+    AppStartupServices& services)
+{
+    if (plan.previous_run_counter < 0 || plan.next_run_counter <= plan.previous_run_counter) {
+        return pp::foundation::Status::invalid_argument("startup plan has invalid run counter state");
+    }
+
+    services.store_run_counter(plan.next_run_counter);
+    if (plan.save_preferences) {
+        services.save_preferences();
+    }
+
+    return pp::foundation::Status::success();
+}
+
+[[nodiscard]] inline pp::foundation::Status execute_app_startup_runtime_plan(
+    const AppStartupPlan& plan,
+    AppStartupServices& services)
+{
+    if (plan.previous_run_counter < 0 || plan.next_run_counter <= plan.previous_run_counter) {
+        return pp::foundation::Status::invalid_argument("startup plan has invalid run counter state");
+    }
+
+    if (plan.start_timelapse) {
+        services.start_timelapse_recording();
+    }
+    services.apply_vr_controllers_enabled(plan.vr_controllers_enabled);
+    if (plan.show_license_warning) {
+        services.show_license_warning();
+    }
+
+    return pp::foundation::Status::success();
+}
+
+} // namespace pp::app