From 79baffbd34558d1a8fe451ed71421b0905d95edc Mon Sep 17 00:00:00 2001
From: Christoph Reiter <reiter.christoph@gmail.com>
Date: Tue, 26 Sep 2023 08:29:04 +0200
Subject: [PATCH] Add font options custom palette color APIs

Adds:

* FontOptions.set_custom_palette_color
* FontOptions.get_custom_palette_color

See #309
---
 cairo/__init__.pyi | 32 ++++++++++++++++++++++++++++++++
 cairo/font.c       | 30 ++++++++++++++++++++++++++++++
 tests/test_font.py | 11 +++++++++++
 3 files changed, 73 insertions(+)

diff --git a/cairo/__init__.pyi b/cairo/__init__.pyi
index 53a50705..3b9ab4cd 100644
--- a/cairo/__init__.pyi
+++ b/cairo/__init__.pyi
@@ -1653,6 +1653,38 @@ class FontOptions:
         .. versionadded:: 1.25.0 Only available with cairo 1.17.8+
         """
 
+    def set_custom_palette_color(self, index: int, red: float, green: float, blue: float, alpha: float) -> None:
+        """
+        :param index: the index of the color to set
+        :param red: red component of color
+        :param green: green component of color
+        :param blue: blue component of color
+        :param alpha: alpha component of color
+
+        Sets a custom palette color for the font options object. This overrides
+        the palette color at the specified color index. This override is
+        independent of the selected palette index and will remain in place even
+        if :meth:`FontOptions.set_color_palette` is called to change the palette
+        index.
+
+        It is only possible to override color indexes already in the font
+        palette.
+
+        .. versionadded:: 1.25.0 Only available with cairo 1.17.8+
+        """
+
+    def get_custom_palette_color(self, index: int) -> Tuple[float, float, float, float]:
+        """
+        :param index: the index of the color to get
+        :returns: a (red, green, blue, alpha) tuple of float
+        :raises Error: if no custom color exists for the color index.
+
+        Gets the custom palette color for the color index for the font options
+        object.
+
+        .. versionadded:: 1.25.0 Only available with cairo 1.17.8+
+        """
+
 class ScaledFont:
     """
     A *ScaledFont* is a font scaled to a particular size and device resolution. A
diff --git a/cairo/font.c b/cairo/font.c
index 3a6b2a9b..f2833aa1 100644
--- a/cairo/font.c
+++ b/cairo/font.c
@@ -710,6 +710,34 @@ static PyObject *
 font_options_get_color_palette (PycairoFontOptions *o, PyObject *ignored) {
   return PyLong_FromUnsignedLong (cairo_font_options_get_color_palette (o->font_options));
 }
+
+static PyObject *
+font_options_set_custom_palette_color (PycairoFontOptions *o, PyObject *args) {
+  double red, green, blue, alpha;
+  unsigned int index;
+
+  if (!PyArg_ParseTuple (args, "Idddd:FontOptions.set_custom_palette_color",
+      &index, &red, &green, &blue, &alpha))
+    return NULL;
+
+  cairo_font_options_set_custom_palette_color (o->font_options, index, red, green, blue, alpha);
+  RETURN_NULL_IF_CAIRO_FONT_OPTIONS_ERROR(o->font_options);
+  Py_RETURN_NONE;
+}
+
+static PyObject *
+font_options_get_custom_palette_color (PycairoFontOptions *o, PyObject *args) {
+  double red, green, blue, alpha;
+  unsigned int index;
+  cairo_status_t status;
+
+  if (!PyArg_ParseTuple (args, "I:FontOptions.get_custom_palette_color", &index))
+    return NULL;
+
+  status = cairo_font_options_get_custom_palette_color (o->font_options, index, &red, &green, &blue, &alpha);
+  RETURN_NULL_IF_CAIRO_ERROR (status);
+  return Py_BuildValue("(dddd)", red, green, blue, alpha);
+}
 #endif
 
 static PyObject *
@@ -865,6 +893,8 @@ static PyMethodDef font_options_methods[] = {
   {"set_color_mode",    (PyCFunction)font_options_set_color_mode, METH_VARARGS},
   {"get_color_palette", (PyCFunction)font_options_get_color_palette, METH_NOARGS},
   {"set_color_palette", (PyCFunction)font_options_set_color_palette, METH_VARARGS},
+  {"get_custom_palette_color", (PyCFunction)font_options_get_custom_palette_color, METH_VARARGS},
+  {"set_custom_palette_color", (PyCFunction)font_options_set_custom_palette_color, METH_VARARGS},
 #endif
   {"get_antialias",     (PyCFunction)font_options_get_antialias,  METH_NOARGS},
   {"get_hint_metrics",  (PyCFunction)font_options_get_hint_metrics,
diff --git a/tests/test_font.py b/tests/test_font.py
index d6fa40c7..e504a374 100644
--- a/tests/test_font.py
+++ b/tests/test_font.py
@@ -23,6 +23,17 @@ def scaled_font(font_face, font_options):
         font_face, cairo.Matrix(), cairo.Matrix(), font_options)
 
 
+@pytest.mark.skipif(not hasattr(cairo.FontOptions, "set_custom_palette_color"),
+                    reason="too old cairo")
+def test_font_options_custom_palette_color(font_options):
+    font_options.set_custom_palette_color(42, 0.25, 0.5, 0.75, 1.0)
+    with pytest.raises(cairo.Error) as exc_info:
+        font_options.get_custom_palette_color(24)
+    assert exc_info.value.status == cairo.Status.INVALID_INDEX
+    assert font_options.get_custom_palette_color(42) == (0.25, 0.5, 0.75, 1.0)
+    assert isinstance(font_options.get_custom_palette_color(42), tuple)
+
+
 @pytest.mark.skipif(not hasattr(cairo.FontOptions, "set_color_mode"),
                     reason="too old cairo")
 def test_font_options_set_color_mode(font_options):