From 751e39c35bbf5fd34d9167558070851cbb68ee01 Mon Sep 17 00:00:00 2001
From: Cristian Le <cristian.le@mpsd.mpg.de>
Date: Tue, 27 Jun 2023 11:16:09 +0200
Subject: [PATCH] Add doxygen and graphviz support

---
 .readthedocs.yaml |  3 +++
 Doxyfile          |  6 +++---
 docs/conf.py      | 27 +++++++++++++++++++++++++--
 3 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index ffba68da..5ae534d9 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -7,6 +7,9 @@ python:
         - docs
 build:
   os: ubuntu-22.04
+  apt_packages:
+    - doxygen
+    - graphviz
   tools:
     python: "3.11"
 sphinx:
diff --git a/Doxyfile b/Doxyfile
index 07b385ec..a1143702 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -57,7 +57,7 @@ PROJECT_BRIEF          = "Popular C++ unit testing framework"
 # entered, it will be relative to the location where doxygen was started. If
 # left blank the current directory will be used.
 
-OUTPUT_DIRECTORY       = docs/doxygen
+OUTPUT_DIRECTORY       = docs/build/doxygen
 
 # If the CREATE_SUBDIRS tag is set to YES then doxygen will create 4096 sub-
 # directories (in 2 levels) under the output directory of each output format and
@@ -1088,7 +1088,7 @@ IGNORE_PREFIX          =
 # If the GENERATE_HTML tag is set to YES, doxygen will generate HTML output
 # The default value is: YES.
 
-GENERATE_HTML          = YES
+GENERATE_HTML          = NO
 
 # The HTML_OUTPUT tag is used to specify where the HTML docs will be put. If a
 # relative path is entered the value of OUTPUT_DIRECTORY will be put in front of
@@ -1946,7 +1946,7 @@ MAN_LINKS              = NO
 # captures the structure of the code including all documentation.
 # The default value is: NO.
 
-GENERATE_XML           = NO
+GENERATE_XML           = YES
 
 # The XML_OUTPUT tag is used to specify where the XML pages will be put. If a
 # relative path is entered the value of OUTPUT_DIRECTORY will be put in front of
diff --git a/docs/conf.py b/docs/conf.py
index 8e161469..37d16f2f 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,3 +1,9 @@
+import os
+import subprocess
+
+from sphinx.application import Sphinx
+from pathlib import Path
+
 project = 'Catch2'
 copyright = '2023, Martin Hořeňovský'
 author = 'Martin Hořeňovský'
@@ -19,11 +25,28 @@ exclude_patterns = [
 ]
 source_suffix = [".md"]
 
-
 html_theme = 'furo'
-#html_static_path = ['_static']
+# html_static_path = ['_static']
 
 myst_enable_extensions = [
     "tasklist",
     "colon_fence",
 ]
+
+breathe_projects = {
+    "Catch2": "build/doxygen/xml",
+}
+breathe_default_project = "Catch2"
+
+
+def generate_doxygen_xml(app: Sphinx):
+    """
+    Run the doxygen commands
+    """
+    os.chdir(Path(app.confdir).parent)
+    subprocess.run(["doxygen"])
+
+
+def setup(app: Sphinx):
+    # Add hook for building doxygen xml when needed
+    app.connect("builder-inited", generate_doxygen_xml)