From 7919683748ce567a93db43f99fa7cf3af54c7102 Mon Sep 17 00:00:00 2001
From: Jan <jan@laupetin.net>
Date: Tue, 23 Jan 2024 21:53:01 +0100
Subject: [PATCH] chore: write header with git version

---
 premake5.lua              |  8 ++++++++
 tools/scripts/version.lua | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)
 create mode 100644 tools/scripts/version.lua

diff --git a/premake5.lua b/premake5.lua
index 0152b930..6d9b19f7 100644
--- a/premake5.lua
+++ b/premake5.lua
@@ -3,6 +3,7 @@ include "tools/scripts/including.lua"
 include "tools/scripts/linking.lua"
 include "tools/scripts/options.lua"
 include "tools/scripts/platform.lua"
+include "tools/scripts/version.lua"
 
 -- ==================
 -- Workspace
@@ -63,6 +64,13 @@ workspace "OpenAssetTools"
         "__STDC_WANT_LIB_EXT1__=1",
         "_CRT_SECURE_NO_WARNINGS"
     }
+
+    -- Write the current version to a header
+    -- This is better than adding it as macro here since changing a global macro would cause a full rebuild
+    WriteVersionHeader()
+    includedirs {
+        GetVersionHeaderFolder()
+    }
     
     filter "options:debug-structureddatadef"
         defines { "STRUCTUREDDATADEF_DEBUG" }
diff --git a/tools/scripts/version.lua b/tools/scripts/version.lua
new file mode 100644
index 00000000..dc0087f9
--- /dev/null
+++ b/tools/scripts/version.lua
@@ -0,0 +1,36 @@
+local BuildSubFolderFolder = "premake"
+local HeaderFileName = "GitVersion.h"
+
+function GetGitVersion()
+    result, errorCode = os.outputof("git describe --tags")
+
+    if errorCode == 0 then
+        return result
+    end
+
+    return "Unknown"
+end
+
+function GetVersionHeaderFolder()
+    return path.join(BuildFolder(), BuildSubFolderFolder)
+end
+
+function WriteVersionHeader()
+    local folder = GetVersionHeaderFolder()
+    local file = path.join(folder, HeaderFileName)
+    local content = string.format([[
+#pragma once
+
+#define GIT_VERSION "%s"
+    ]], GetGitVersion())
+
+    if os.isdir(folder) ~= True then
+        os.mkdir(folder)
+    end
+
+    local ok, err = os.writefile_ifnotequal(content, file)
+
+    if ok == -1 then
+        error("Could not create version file: " .. err)
+    end
+end