Add italics, link detection, lists to minimd

minimd.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+
+import re
+
+# https://stackoverflow.com/a/6041965
+RE_URL = re.compile(r'(https?://([\w_-]+(?:(?:\.[\w_-]+)+))([\w.,@?^=%&:/~+#-]*[\w@?^=%&/~+#-]))')
+RE_EM = re.compile(r'\*(.*?)\*')
+RE_LIST = re.compile(r'(-|[0-9]\.) .*')
+
+def html(text):
+    # Replace angle brackets to prevent XSS
+    # Also replace ampersands to prevent surprises.
+    text = text.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
+
+    html = ['<p>']
+    lines = text.split('\n')
+    in_code = False
+    in_list = False
+
+    for l in lines:
+        if l == '':
+            in_list = False
+            if in_code:
+                html.append('</pre>')
+                in_code = False
+            html.append('</p><p>')
+            continue
+        if l.startswith('  '):
+            in_list = False
+            l = l[2:]
+            if not in_code:
+                html.append('<pre>')
+                in_code = True
+            html.append(l)
+            continue
+        if in_code:
+            html.append('</pre>')
+            in_code = False
+        l = RE_EM.sub(r'<em>\1</em>', l)
+        l = RE_URL.sub(r'<a href="\1">\1</a>', l)
+        if RE_LIST.match(l):
+            if in_list:
+                html.append('<br>')
+            in_list = True
+        else:
+            in_list = False
+        html.append(l)
+
+    if in_code:
+        html.append('</pre>')
+    html.append('</p>')
+    return ''.join(html)
+
+
+if __name__ == '__main__':
+    import sys
+    print(html(sys.stdin.read()))
+