From 226cc92b01784f9fb7583821f2e982232068599c Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 29 Jun 2024 16:18:43 +0530
Subject: [PATCH] API to add font file to system font lookup

---
 kitty/core_text.m         | 11 +++++++++++
 kitty/fast_data_types.pyi |  4 ++++
 kitty/fontconfig.c        | 15 +++++++++++++++
 kitty/fonts/render.py     |  2 ++
 4 files changed, 32 insertions(+)

diff --git a/kitty/core_text.m b/kitty/core_text.m
index 88ec9bda3..471432018 100644
--- a/kitty/core_text.m
+++ b/kitty/core_text.m
@@ -1103,8 +1103,19 @@ repr(CTFace *self) {
 }
 
 
+static PyObject*
+coretext_add_font_file(PyObject UNUSED *_self, PyObject *args) {
+    const unsigned char *path = NULL; Py_ssize_t sz;
+    if (!PyArg_ParseTuple(args, "s#", &path, &sz)) return NULL;
+    RAII_CoreFoundation(CFURLRef, url, CFURLCreateFromFileSystemRepresentation(kCFAllocatorDefault, path, sz, false));
+    RAII_CoreFoundation(CFArrayRef, descriptors, CTFontManagerCreateFontDescriptorsFromURL(url));
+    CTFontManagerEnableFontDescriptors(descriptors, true);
+    Py_RETURN_TRUE;
+}
+
 static PyMethodDef module_methods[] = {
     METHODB(coretext_all_fonts, METH_O),
+    METHODB(coretext_add_font_file, METH_VARARGS),
     {NULL, NULL, 0, NULL}        /* Sentinel */
 };
 
diff --git a/kitty/fast_data_types.pyi b/kitty/fast_data_types.pyi
index a8c715f6f..5411d5c7a 100644
--- a/kitty/fast_data_types.pyi
+++ b/kitty/fast_data_types.pyi
@@ -425,6 +425,10 @@ def fc_match_postscript_name(
     pass
 
 
+def fc_add_font_file(path: str) -> bool: ...
+def coretext_add_font_file(path: str) -> bool: ...
+
+
 class FeatureData(TypedDict):
     name: NotRequired[str]
     tooltip: NotRequired[str]
diff --git a/kitty/fontconfig.c b/kitty/fontconfig.c
index bd82a5b44..7f75467d5 100644
--- a/kitty/fontconfig.c
+++ b/kitty/fontconfig.c
@@ -41,6 +41,7 @@ static void* libfontconfig_handle = NULL;
 #define FcPatternCreate dynamically_loaded_fc_symbol.PatternCreate
 #define FcPatternGetBool dynamically_loaded_fc_symbol.PatternGetBool
 #define FcPatternAddCharSet dynamically_loaded_fc_symbol.PatternAddCharSet
+#define FcConfigAppFontAddFile dynamically_loaded_fc_symbol.ConfigAppFontAddFile
 
 static struct {
     FcBool(*Init)(void);
@@ -65,6 +66,7 @@ static struct {
     FcPattern * (*PatternCreate) (void);
     FcResult (*PatternGetBool) (const FcPattern *p, const char *object, int n, FcBool *b);
     FcBool (*PatternAddCharSet) (FcPattern *p, const char *object, const FcCharSet *c);
+    FcBool (*ConfigAppFontAddFile) (FcConfig *config, const FcChar8 *file);
 } dynamically_loaded_fc_symbol = {0};
 #define LOAD_FUNC(name) {\
     *(void **) (&dynamically_loaded_fc_symbol.name) = dlsym(libfontconfig_handle, "Fc" #name); \
@@ -115,6 +117,7 @@ load_fontconfig_lib(void) {
         LOAD_FUNC(PatternCreate);
         LOAD_FUNC(PatternGetBool);
         LOAD_FUNC(PatternAddCharSet);
+        LOAD_FUNC(ConfigAppFontAddFile);
 }
 #undef LOAD_FUNC
 
@@ -491,10 +494,22 @@ end:
 }
 
 #undef AP
+
+static PyObject*
+fc_add_font_file(PyObject UNUSED *self, PyObject *args) {
+    ensure_initialized();
+    const char *path = NULL;
+    if (!PyArg_ParseTuple(args, "s", &path)) return NULL;
+    if (FcConfigAppFontAddFile(NULL, (const unsigned char*)path)) Py_RETURN_TRUE;
+    Py_RETURN_FALSE;
+}
+
+
 static PyMethodDef module_methods[] = {
     {"fc_list", (PyCFunction)(void (*) (void))(fc_list), METH_VARARGS | METH_KEYWORDS, NULL},
     METHODB(fc_match, METH_VARARGS),
     METHODB(fc_match_postscript_name, METH_VARARGS),
+    METHODB(fc_add_font_file, METH_VARARGS),
     {NULL, NULL, 0, NULL}        /* Sentinel */
 };
 
diff --git a/kitty/fonts/render.py b/kitty/fonts/render.py
index 2db1c3dcb..091480405 100644
--- a/kitty/fonts/render.py
+++ b/kitty/fonts/render.py
@@ -33,7 +33,9 @@ from .common import get_font_files
 
 if is_macos:
     from .core_text import font_for_family as font_for_family_macos
+    from kitty.fast_data_types import coretext_add_font_file as add_font_file
 else:
+    from kitty.fast_data_types import fc_add_font_file as add_font_file
     from .fontconfig import font_for_family as font_for_family_fontconfig
 
 FontObject = Union[CoreTextFont, FontConfigPattern]