From 816d003dd4a2a982c78c37bf52245726853db34a Mon Sep 17 00:00:00 2001
From: Ben Kurtovic <ben.kurtovic@gmail.com>
Date: Thu, 8 May 2014 13:10:57 -0400
Subject: [PATCH] More work on query parsing.

---
 bitshift/query/__init__.py | 106 +++++++++++++++++++++++++++++++++------------
 bitshift/query/nodes.py    |   2 +-
 2 files changed, 80 insertions(+), 28 deletions(-)

diff --git a/bitshift/query/__init__.py b/bitshift/query/__init__.py
index fc602f6..711e359 100644
--- a/bitshift/query/__init__.py
+++ b/bitshift/query/__init__.py
@@ -1,46 +1,98 @@
+"""
+This subpackage contains code to parse search queries received from the
+frontend into trees that can be used by the database backend.
+"""
+
+from shlex import split
+
 from .nodes import *  ## TODO
 from .tree import Tree
+from ..languages import LANGS
 
 __all__ = ["QueryParseException", "parse_query"]
 
 class QueryParseException(Exception):
-    """Raised by parse_query when a query is invalid."""
+    """Raised by parse_query() when a query is invalid."""
     pass
 
+class _QueryParser(object):
+    """Wrapper class with methods to parse queries. Used as a singleton."""
+
+    def __init__(self):
+        prefixes = {
+            "language": _parse_language,
+            "author": _parse_author,
+            "modified": _parse_modified,
+            "created": _parse_created,
+            "symbol": _parse_symbol,
+            "function": _parse_function,
+            "class": _parse_class,
+            "variable": _parse_variable
+        }
 
-def parse_query(query):
-    """
-    Parse a search query.
+    def _parse_language(self, term):
+        pass
+
+    def _parse_author(self, term):
+        pass
 
-    The result is normalized with a sorting function so that ``"foo OR bar"``
-    and ``"bar OR foo"`` result in the same tree. This is important for caching
-    purposes.
+    def _parse_modified(self, term):
+        pass
+
+    def _parse_created(self, term):
+        pass
+
+    def _parse_symbol(self, term):
+        pass
 
-    :param query: The query be converted.
-    :type query: str
+    def _parse_function(self, term):
+        pass
 
-    :return: A tree storing the data in the query.
-    :rtype: :py:class:`~.query.tree.Tree`
+    def _parse_class(self, term):
+        pass
 
-    :raises: :py:class:`.QueryParseException`
-    """
-    for term in query.split(" "):
+    def _parse_variable(self, term):
         pass
 
-    language:"Python"
-    lang:
-    l:
+    def parse(self, query):
+        """
+        Parse a search query.
+
+        The result is normalized with a sorting function so that ``"foo OR bar"``
+        and ``"bar OR foo"`` result in the same tree. This is important for caching
+        purposes.
+
+        :param query: The query be converted.
+        :type query: str
+
+        :return: A tree storing the data in the query.
+        :rtype: :py:class:`~.query.tree.Tree`
+
+        :raises: :py:class:`.QueryParseException`
+        """
+        for term in split(query):
+            if ":" in term and not term[0] == ":":
+                prefix = term.split(":")[0]
+
+
+
+        # language:"Python"
+        # lang:
+        # l:
+
+        # author:"Ben Kurtovic"
+
+        # modified:before
+        # modified:after
+        # created:before
+        # created:after:"Jaunary 4, 2014"
 
-    author:"Ben Kurtovic"
+        # func:"foobar"
+        # func:re|gex:"foo?b|car"
 
-    modified:before
-    modified:after
-    created:before
-    created:after:"Jaunary 4, 2014"
+        # "foo" -> Tree()
+        # "foo bar" -> "foo bar" OR ("foo" or "bar")
+        # "foo bar baz" -> ""foo bar baz" OR ("foo" OR "bar baz") OR ("foo" OR "bar baz") OR ('foo' OR 'bar' OR 'baz')"
 
-    func:"foobar"
-    func:re|gex:"foo?b|car"
 
-    # "foo" -> Tree()
-    # "foo bar" -> "foo bar" OR ("foo" or "bar")
-    # "foo bar baz" -> ""foo bar baz" OR ("foo" OR "bar baz") OR ("foo" OR "bar baz") OR ('foo' OR 'bar' OR 'baz')"
+parse_query = _QueryParser().parse
diff --git a/bitshift/query/nodes.py b/bitshift/query/nodes.py
index 8dc7fe9..ff9d21b 100644
--- a/bitshift/query/nodes.py
+++ b/bitshift/query/nodes.py
@@ -1,4 +1,4 @@
-# from ..languages import LANGS
+from ..languages import LANGS
 
 __all__ = ["String", "Regex", "Text", "Language", "Date", "Author", "Symbol",
            "BinaryOp", "UnaryOp"]