From 7cd7d118e284df0e17967f5874afdd3806f10c4a Mon Sep 17 00:00:00 2001
From: djcb <djcb@djcbsoftware.nl>
Date: Thu, 26 Oct 2017 21:31:22 +0300
Subject: [PATCH] query-parser: support phrase queries

---
 lib/parser/test-tokenizer.cc |  7 +++---
 lib/parser/tokenizer.cc      | 20 +++++++++--------
 lib/parser/utils.cc          | 14 ++++++++++++
 lib/parser/utils.hh          | 12 +++++++++++
 lib/parser/xapian.cc         | 42 ++++++++++++++++++++++++++++--------
 5 files changed, 73 insertions(+), 22 deletions(-)

diff --git a/lib/parser/test-tokenizer.cc b/lib/parser/test-tokenizer.cc
index 2e4cdeec..a773890c 100644
--- a/lib/parser/test-tokenizer.cc
+++ b/lib/parser/test-tokenizer.cc
@@ -118,11 +118,10 @@ static void
 test_escape ()
 {
 	CaseVec cases = {
-		{ "foo\"bar\"",      Tokens{Token{3, TT::Data, "foo"},
-					      Token{8, TT::Data, "bar"}}},
+		{ "foo\"bar\"",      Tokens{Token{8, TT::Data, "foobar"}}},
 		{ "\"fnorb\"",      Tokens{Token{7, TT::Data, "fnorb"}}},
-		{ "\\\"fnorb\\\"",  Tokens{Token{9, TT::Data, "\"fnorb\""}}},
-		{ "foo\\\"bar\\\"",  Tokens{Token{10, TT::Data, "foo\"bar\""}}}
+		{ "\\\"fnorb\\\"",  Tokens{Token{9, TT::Data, "fnorb"}}},
+		{ "foo\\\"bar\\\"",  Tokens{Token{10, TT::Data, "foobar"}}}
 	};
 
 	test_cases (cases);
diff --git a/lib/parser/tokenizer.cc b/lib/parser/tokenizer.cc
index 7267ff25..75e0dfcf 100644
--- a/lib/parser/tokenizer.cc
+++ b/lib/parser/tokenizer.cc
@@ -27,12 +27,11 @@ using namespace Mux;
 static bool
 is_separator (char c)
 {
-	const auto seps = std::string (":()\"");
-
 	if (isblank(c))
 		return true;
-	else
-		return seps.find(c) != std::string::npos;
+
+	const auto seps = std::string ("()");
+	return seps.find(c) != std::string::npos;
 }
 
 
@@ -80,8 +79,14 @@ eat_token (std::string& food, size_t& pos)
 				continue;
 		}
 
-		if (kar == '"' && !escaped && quoted)
-			return Token{pos, Token::Type::Data, value};
+		if (kar == '"') {
+			if (!escaped && quoted)
+				return Token{pos, Token::Type::Data, value};
+			else {
+				quoted = true;
+				continue;
+			}
+		}
 
 		if (!quoted && !escaped && is_separator(kar)) {
 
@@ -90,9 +95,6 @@ eat_token (std::string& food, size_t& pos)
 				return op_or_value(pos, value);
 			}
 
-			if (kar == '"')
-				quoted = true;
-
 			if (quoted || isblank(kar))
 				continue;
 
diff --git a/lib/parser/utils.cc b/lib/parser/utils.cc
index 6b27991d..a21b26cc 100644
--- a/lib/parser/utils.cc
+++ b/lib/parser/utils.cc
@@ -110,6 +110,20 @@ Mux::utf8_flatten (const std::string& str)
 }
 
 
+std::vector<std::string>
+Mux::split (const std::string& str, const std::string& sepa)
+{
+	char **parts = g_strsplit(str.c_str(), sepa.c_str(), -1);
+	std::vector<std::string> vec;
+	for (auto part = parts; part && *part; ++part)
+		vec.push_back (*part);
+
+	g_strfreev(parts);
+
+	return vec;
+}
+
+
 std::string
 Mux::quote (const std::string& str)
 {
diff --git a/lib/parser/utils.hh b/lib/parser/utils.hh
index 2a916430..f9389f9e 100644
--- a/lib/parser/utils.hh
+++ b/lib/parser/utils.hh
@@ -18,6 +18,7 @@
 */
 
 #include <string>
+#include <vector>
 
 #ifndef __UTILS_HH__
 #define __UTILS_HH__
@@ -33,6 +34,17 @@ namespace Mux {
  */
 std::string utf8_flatten (const std::string& str);
 
+/**
+ * Split a string in parts
+ *
+ * @param str a string
+ * @param sepa the separator
+ *
+ * @return the parts.
+ */
+std::vector<std::string> split (const std::string& str,
+				const std::string& sepa);
+
 /**
  * Quote & escape a string
  *
diff --git a/lib/parser/xapian.cc b/lib/parser/xapian.cc
index a14e304f..229c9ce5 100644
--- a/lib/parser/xapian.cc
+++ b/lib/parser/xapian.cc
@@ -48,6 +48,35 @@ xapian_query_op (const Mux::Tree& tree)
 	return Xapian::Query(op, childvec.begin(), childvec.end());
 }
 
+static Xapian::Query
+xapian_query_value (const Mux::Tree& tree)
+{
+	const auto v = dynamic_cast<Value*> (tree.node.data.get());
+	const auto parts = split (v->value, " ");
+
+	std::vector<Xapian::Query> phvec;
+	for (const auto p: parts)
+		phvec.push_back(Xapian::Query(v->prefix + p));
+
+	if (parts.empty())
+		return Xapian::Query::MatchNothing; // shouldn't happen
+
+	if (parts.size() == 1)
+		return phvec.front();
+
+	return Xapian::Query (Xapian::Query::OP_PHRASE,
+			      phvec.begin(), phvec.end());
+}
+
+static Xapian::Query
+xapian_query_range (const Mux::Tree& tree)
+{
+	const auto r = dynamic_cast<Range*> (tree.node.data.get());
+	return Xapian::Query(Xapian::Query::OP_VALUE_RANGE,
+			     (Xapian::valueno)r->id, r->lower, r->upper);
+}
+
+
 Xapian::Query
 Mux::xapian_query (const Mux::Tree& tree)
 {
@@ -60,15 +89,10 @@ Mux::xapian_query (const Mux::Tree& tree)
 	case Node::Type::OpXor:
 	case Node::Type::OpAndNot:
 		return xapian_query_op (tree);
-	case Node::Type::Value: {
-		const auto v = dynamic_cast<Value*> (tree.node.data.get());
-		return Xapian::Query(v->prefix + v->value);
-	}
-	case Node::Type::Range: {
-		const auto r = dynamic_cast<Range*> (tree.node.data.get());
-		return Xapian::Query(Xapian::Query::OP_VALUE_RANGE,
-				     (Xapian::valueno)r->id, r->lower, r->upper);
-	}
+	case Node::Type::Value:
+		return xapian_query_value (tree);
+	case Node::Type::Range:
+		return xapian_query_range (tree);
 	default:
 		throw std::runtime_error ("invalid query"); // bug
 	}