From 9fa5014d1694899c8ccb371baf0afdc2a75b3f79 Mon Sep 17 00:00:00 2001
From: Vinicius Rangel <me@viniciusrangel.dev>
Date: Thu, 30 Jan 2025 03:59:52 -0300
Subject: [PATCH] savedata: auto-restore backup if needed

---
 .../libraries/save_data/save_instance.cpp     | 20 ++++++++++++++-----
 src/core/libraries/save_data/save_instance.h  |  3 ++-
 src/core/libraries/save_data/save_memory.cpp  |  2 +-
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/src/core/libraries/save_data/save_instance.cpp b/src/core/libraries/save_data/save_instance.cpp
index 367d4871d..26708d2d6 100644
--- a/src/core/libraries/save_data/save_instance.cpp
+++ b/src/core/libraries/save_data/save_instance.cpp
@@ -10,6 +10,7 @@
 #include "common/path_util.h"
 #include "common/singleton.h"
 #include "core/file_sys/fs.h"
+#include "save_backup.h"
 #include "save_instance.h"
 
 constexpr auto OrbisSaveDataBlocksMin2 = 96;    // 3MiB
@@ -140,7 +141,8 @@ SaveInstance& SaveInstance::operator=(SaveInstance&& other) noexcept {
     return *this;
 }
 
-void SaveInstance::SetupAndMount(bool read_only, bool copy_icon, bool ignore_corrupt) {
+void SaveInstance::SetupAndMount(bool read_only, bool copy_icon, bool ignore_corrupt,
+                                 bool dont_restore_backup) {
     if (mounted) {
         UNREACHABLE_MSG("Save instance is already mounted");
     }
@@ -159,13 +161,21 @@ void SaveInstance::SetupAndMount(bool read_only, bool copy_icon, bool ignore_cor
         }
         exists = true;
     } else {
+        std::optional<fs::filesystem_error> err;
         if (!ignore_corrupt && fs::exists(corrupt_file_path)) {
-            throw fs::filesystem_error("Corrupted save data", corrupt_file_path,
+            err = fs::filesystem_error("Corrupted save data", corrupt_file_path,
+                                       std::make_error_code(std::errc::illegal_byte_sequence));
+        } else if (!param_sfo.Open(param_sfo_path)) {
+            err = fs::filesystem_error("Failed to read param.sfo", param_sfo_path,
                                        std::make_error_code(std::errc::illegal_byte_sequence));
         }
-        if (!param_sfo.Open(param_sfo_path)) {
-            throw fs::filesystem_error("Failed to read param.sfo", param_sfo_path,
-                                       std::make_error_code(std::errc::illegal_byte_sequence));
+        if (err.has_value()) {
+            if (dont_restore_backup) {
+                throw err.value();
+            }
+            if (Backup::Restore(save_path)) {
+                return SetupAndMount(read_only, copy_icon, ignore_corrupt, true);
+            }
         }
     }
 
diff --git a/src/core/libraries/save_data/save_instance.h b/src/core/libraries/save_data/save_instance.h
index fb4f544ce..6e7ac8f66 100644
--- a/src/core/libraries/save_data/save_instance.h
+++ b/src/core/libraries/save_data/save_instance.h
@@ -78,7 +78,8 @@ public:
     SaveInstance& operator=(const SaveInstance& other) = delete;
     SaveInstance& operator=(SaveInstance&& other) noexcept;
 
-    void SetupAndMount(bool read_only = false, bool copy_icon = false, bool ignore_corrupt = false);
+    void SetupAndMount(bool read_only = false, bool copy_icon = false, bool ignore_corrupt = false,
+                       bool dont_restore_backup = false);
 
     void Umount();
 
diff --git a/src/core/libraries/save_data/save_memory.cpp b/src/core/libraries/save_data/save_memory.cpp
index 6f05d8926..13e122c60 100644
--- a/src/core/libraries/save_data/save_memory.cpp
+++ b/src/core/libraries/save_data/save_memory.cpp
@@ -126,7 +126,7 @@ size_t SetupSaveMemory(OrbisUserServiceUserId user_id, u32 slot_id, std::string_
 
     const auto memory = save_dir / FilenameSaveDataMemory;
     if (fs::exists(memory)) {
-        return {fs::file_size(memory)};
+        return fs::file_size(memory);
     }
 
     return 0;