1 files changed, 94 insertions, 0 deletions
diff --git a/filters/syntax-highlighting.py b/filters/syntax-highlighting.py
new file mode 100755
index 0000000..d757e2d
--- /dev/null
+++ b/filters/syntax-highlighting.py
@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+
+# This script uses Pygments and Python3. You must have both installed
+# for this to work.
+#
+# http://pygments.org/
+# http://python.org/
+#
+# It may be used with the source-filter or repo.source-filter settings
+# in cgitrc.
+#
+# The following environment variables can be used to retrieve the
+# configuration of the repository for which this script is called:
+# CGIT_REPO_URL        ( = repo.url       setting )
+# CGIT_REPO_NAME       ( = repo.name      setting )
+# CGIT_REPO_PATH       ( = repo.path      setting )
+# CGIT_REPO_OWNER      ( = repo.owner     setting )
+# CGIT_REPO_DEFBRANCH  ( = repo.defbranch setting )
+# CGIT_REPO_SECTION    ( = section        setting )
+# CGIT_REPO_CLONE_URL  ( = repo.clone-url setting )
+
+
+import sys
+import io
+from pygments import highlight
+from pygments.util import ClassNotFound
+from pygments.lexers import TextLexer
+from pygments.lexers import guess_lexer
+from pygments.lexers import guess_lexer_for_filename
+from pygments.formatters import HtmlFormatter
+
+
+# Pygments' token classes, mapped onto the --syn-* custom properties that
+# cgit.css defines. The fallbacks are the palette those properties default to,
+# so that the output stays readable under a stylesheet without them.
+SYNTAX_COLORS = (
+	(('k', 'kc', 'kd', 'kn', 'kr'), '--syn-keyword', '#000',
+		'font-weight: bold'),
+	(('kp',), '--syn-keyword', '#000', None),
+	(('kt',), '--syn-type', '#010181', None),
+	(('nc', 'nf', 'nn', 'ne'), '--syn-keyword-alt', '#0057ae', None),
+	(('s', 'sa', 'sb', 'sc', 'dl', 'sd', 's2', 'sh', 'sx', 'sr', 's1', 'ss'),
+		'--syn-string', '#bf0303', None),
+	(('se',), '--syn-escape', '#f0f', None),
+	(('si',), '--syn-interpolation', '#0057ae', None),
+	(('c', 'ch', 'cm', 'c1', 'cs'), '--syn-comment', '#838183',
+		'font-style: italic'),
+	(('cp', 'cpf'), '--syn-preproc', '#008200', None),
+	(('m', 'mb', 'mf', 'mh', 'mi', 'mo', 'il'), '--syn-number', '#b07e00',
+		None),
+	(('o', 'ow', 'p'), '--syn-operator', '#000', None),
+	(('err',), '--syn-error', '#bf0303', None),
+	(('gd',), '--red', 'red', None),
+	(('gi',), '--green', 'green', None),
+	(('lineno', 'linenos'), '--syn-linenum', '#555', None),
+)
+
+
+def style_defs(prefix='.highlight'):
+	rules = []
+	for classes, prop, fallback, extra in SYNTAX_COLORS:
+		selector = ', '.join('%s .%s' % (prefix, c) for c in classes)
+		decls = 'color: var(%s, %s)' % (prop, fallback)
+		if extra:
+			decls += '; ' + extra
+		rules.append('%s { %s }' % (selector, decls))
+	rules.append('%s .hll { background-color: var(--syn-mark-bg, #ffb) }'
+		% prefix)
+	return '\n'.join(rules) + '\n'
+
+
+sys.stdin = io.TextIOWrapper(sys.stdin.buffer, encoding='utf-8', errors='replace')
+sys.stdout = io.TextIOWrapper(sys.stdout.buffer, encoding='utf-8', errors='replace')
+data = sys.stdin.read()
+filename = sys.argv[1]
+formatter = HtmlFormatter(nobackground=True)
+
+try:
+	lexer = guess_lexer_for_filename(filename, data)
+except ClassNotFound:
+	# check if there is any shebang
+	if data[0:2] == '#!':
+		lexer = guess_lexer(data)
+	else:
+		lexer = TextLexer()
+except TypeError:
+	lexer = TextLexer()
+
+# highlight! :-)
+# printout the css definitions for pygments' token classes as well
+sys.stdout.write('<style>')
+sys.stdout.write(style_defs('.highlight'))
+sys.stdout.write('</style>')
+sys.stdout.write(highlight(data, lexer, formatter, outfile=None))