From 9b8d3be7df307cc921d82b0f66f55787a0125559 Mon Sep 17 00:00:00 2001
From: ytnuf <161308826+ytnuf@users.noreply.github.com>
Date: Wed, 13 Nov 2024 22:02:15 +0000
Subject: [PATCH] Make godot-cpp installable via ScCons

This aims to have feature parity with the installation via cmake
---
 SConstruct        |  2 ++
 tools/godotcpp.py | 88 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 90 insertions(+)

diff --git a/SConstruct b/SConstruct
index 8acea26245..f4caa47659 100644
--- a/SConstruct
+++ b/SConstruct
@@ -48,4 +48,6 @@ if scons_cache_path is not None:
 cpp_tool.generate(env)
 library = env.GodotCPP()
 
+env.InstallableGodotCPP(library)
+
 Return("env")
diff --git a/tools/godotcpp.py b/tools/godotcpp.py
index 77a0740fcd..ca56787ad3 100644
--- a/tools/godotcpp.py
+++ b/tools/godotcpp.py
@@ -338,6 +338,42 @@ def options(opts, env):
     opts.Add(BoolVariable("dev_build", "Developer build with dev-only debugging code (DEV_ENABLED)", False))
     opts.Add(BoolVariable("verbose", "Enable verbose output for the compilation", False))
 
+
+    # Scons lack a default install prefix, so use CMake's as a default for feature parity
+    # https://cmake.org/cmake/help/latest/variable/CMAKE_INSTALL_PREFIX.html
+    opts.Add(
+        PathVariable(
+            "install_prefix_dir",
+            "The directory to install to",
+            "C:/Program Files/godot-cpp" if default_platform == "windows" else "/usr/local",
+            PathVariable.PathAccept
+        )
+    )
+    opts.Add(
+        PathVariable(
+            "install_lib_dir",
+            "The directory to install the library (relative from the prefix)",
+            "lib",
+            PathVariable.PathAccept
+        )
+    )
+    opts.Add(
+        PathVariable(
+            "install_include_dir",
+            "The directory to install the headers (relative from the prefix)",
+            "include",
+            PathVariable.PathAccept
+        )
+    )
+    opts.Add(
+        PathVariable(
+            "install_data_dir",
+            "The directory to install misc files (relative from the prefix)",
+            "share/godot-cpp",
+            PathVariable.PathAccept
+        )
+    )
+
     # Add platform options (custom tools can override platforms)
     for pl in sorted(set(platforms + custom_platforms)):
         tool = Tool(pl, toolpath=get_platform_tools_paths(env))
@@ -526,6 +562,7 @@ def generate(env):
         }
     )
     env.AddMethod(_godot_cpp, "GodotCPP")
+    env.AddMethod(_installable, "InstallableGodotCPP")
 
 
 def _godot_cpp(env):
@@ -571,3 +608,54 @@ def _godot_cpp(env):
 
     env.AppendUnique(LIBS=[env.File("bin/%s" % library_name)])
     return library
+
+
+def _installable(env, library):
+    import itertools
+    import json
+
+    install_lib_dir = os.path.join(env["install_prefix_dir"], env["install_lib_dir"])
+    install_pkgconfig_dir = os.path.join(install_lib_dir, "pkgconfig")
+    install_include_dir = os.path.join(env["install_prefix_dir"], env["install_include_dir"])
+    install_data_dir = os.path.join(env["install_prefix_dir"], env["install_data_dir"])
+
+    # Obtain the gdextension version
+    extension_dir = normalize_path(env.get("gdextension_dir", env.Dir("gdextension").abspath), env)
+    api_filename = normalize_path(env.get("custom_api_file", env.File(extension_dir + "/extension_api.json").abspath), env)
+    with open(api_filename, "r") as api_json_file:
+        api_data = json.load(api_json_file)
+        version_major = api_data["header"]["version_major"]
+        version_minor = api_data["header"]["version_minor"]
+        version_patch = api_data["header"]["version_patch"]
+        gd_version = f"{version_major}.{version_minor}.{version_patch}"
+        api_data = None
+
+    #Configure and install the pkgconfig file
+    libname = str(library[0])
+    pkgconfig = env.Substfile(target="gen/godot-cpp.pc", source="cmake/godot-cpp.pc.in", SUBST_DICT={
+        "@PROJECT_NAME@": "godot-cpp",
+        "@CMAKE_INSTALL_LIBDIR@": install_lib_dir,
+        "@CMAKE_INSTALL_INCLUDEDIR@" : install_include_dir,
+        "@GODOT_API_VERSION@": gd_version,
+        "@GODOTCPP_OUTPUT_NAME@": libname
+    })
+    env.Install(install_pkgconfig_dir, pkgconfig)
+
+    # Install the headers
+    headers_from = []
+    headers_to = []
+    for dir_from, _, file_lst in itertools.chain(os.walk("include/godot_cpp"), os.walk("gen/include/godot_cpp") ):
+        headers_from += [os.path.join(dir_from,filename) for filename in file_lst]
+        dir_to = os.path.join(install_include_dir, dir_from[dir_from.find("/godot_cpp")+1:])
+        headers_to += [os.path.join(dir_to,filename) for filename in file_lst]
+    env.InstallAs(headers_to, headers_from)
+
+    # Install the gdextension files
+    interface_header = os.path.join(extension_dir, "gdextension_interface.h")
+    env.Install(install_include_dir, interface_header)
+    env.Install(install_data_dir, api_filename)
+
+    # Install the static library
+    env.Install(install_lib_dir, library)
+
+    env.Alias("install", env["install_prefix_dir"])