--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+module re_app
+
+import re_parser
+import popcorn
+import popcorn::pop_config
+
+class REHandler
+ super Handler
+
+ redef fun get(req, res) do
+ res.html new RETemplate
+ end
+
+ redef fun post(req, res) do
+ # TODO Retrieve re from post body
+ var re = req.string_arg("re")
+
+ var tpl = new RETemplate
+
+ if re == null or re.is_empty then
+ tpl.error = "Error: empty regexp"
+ res.html tpl
+ return
+ end
+
+ tpl.re = re
+
+ # Parse re
+ var re_parser = new REParser
+ var node = re_parser.parse_re(re)
+
+ if node == null then
+ tpl.error = re_parser.last_error.as(not null)
+ res.html tpl
+ return
+ end
+
+ # Build nfa and dfa
+ var nfa = re_parser.make_nfa(node)
+ tpl.nfa = automaton_to_svg(nfa)
+ tpl.dfa = automaton_to_svg(nfa.to_dfa)
+
+ res.html tpl
+ end
+
+ private fun automaton_to_svg(automaton: Automaton): String do
+ automaton.to_dot(false).write_to_file "dot.tmp"
+ sys.system "dot -Tsvg -osvg.tmp dot.tmp"
+ var svg = "svg.tmp".to_path.read_all
+ sys.system "rm -f dot.tmp svg.tmp"
+ return svg
+ end
+end
+
+class RETemplate
+ super Template
+
+ var re = "a*(b|cd?)+"
+ var nfa: nullable String = null
+ var dfa: nullable String = null
+ var error: nullable String = null
+
+ redef fun rendering do
+ add """
+<!DOCTYPE html>
+<html lang="en">
+ <head>
+ <meta charset="utf-8" />
+ <meta http-equiv="X-UA-Compatible" content="IE=edge" />
+ <meta name="viewport" content="width=device-width, initial-scale=1" />
+ <title>REParser</title>
+ <link rel="stylesheet"
+ href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" />
+ </head>
+ <body>
+ <div class="container">
+ <h1>Regular Expressions to NFA and DFA</h1>
+ <br><br>
+ <label for="re">Enter a regular expression:</label>
+ <form action="/" method="POST" class="input-group">
+ <input id="re" name="re" type="text" class="form-control" value="{{{re}}}">
+ <span class="input-group-btn">
+ <input type="submit" class="btn btn-default" value="Convert" />
+ </span>
+ </form>
+ <br><br>"""
+
+ var error = self.error
+ if error != null then
+ add """<p class="text-danger">{{{error}}}</p>"""
+ end
+
+ var nfa = self.nfa
+ if nfa != null then
+ add """
+ <h2>NFA</h2>
+ <div>{{{nfa}}}</div><br><br>"""
+ end
+
+ var dfa = self.dfa
+ if dfa != null then
+ add """
+ <h2>DFA</h2>
+ <div>{{{dfa}}}</div><br><br>"""
+ end
+
+ add """</div>
+ <div class="text-center text-muted">
+ <p>Powered by <a href="http://nitlanguage.org">nit</a>!</p>
+ </div>
+ </body>
+</html>"""
+ end
+end
+
+var config = new AppConfig
+config.parse_options(args)
+
+var app = new App
+app.use("/", new REHandler)
+app.listen(config.app_host, config.app_port)
nitlanguage / nit.git / commitdiff