[PATCH] Bump RPC API Version 6

[Kevin Morris]

API Version 6 modifies `type=search` functionality: Split `arg` into
keywords separated by spaces (quoted keywords are preserved).

Search for packages containing the literal keyword `blah blah` AND `haha`:
https://aur.archlinux.org/rpc/?v=6&type=search&arg="blah blah"%20haha

Search for packages containing the literal keyword `abc 123`:
https://aur.archlinux.org/rpc/?v=6&type=search&arg="abc 123"

The following example searches for packages that contain `blah` AND `abc`:
https://aur.archlinux.org/rpc/?v=6&type=search&arg=blah%20abc

The legacy method still searches for packages that contain 'blah abc':
https://aur.archlinux.org/rpc/?v=5&type=search&arg=blah%20abc
https://aur.archlinux.org/rpc/?v=5&type=search&arg=blah%20abc

API Version 6 is only considered during a `search` of `name` or
`name-desc`.

Note: This change was written as a solution to
https://bugs.archlinux.org/task/49133.

PS: + Some spacing issues fixed in comments.

Signed-off-by: Kevin Morris <kevr.gtalk at gmail.com>
---
 doc/rpc.txt               |  4 +++
 web/lib/aurjson.class.php | 66 ++++++++++++++++++++++++++++++++++-----
 2 files changed, 62 insertions(+), 8 deletions(-)

diff --git a/doc/rpc.txt b/doc/rpc.txt
index 3148ebea..b0f5c4e1 100644
--- a/doc/rpc.txt
+++ b/doc/rpc.txt
@@ -39,6 +39,10 @@ Examples
   `/rpc/?v=5&type=search&by=makedepends&arg=boost`
 `search` with callback::
   `/rpc/?v=5&type=search&arg=foobar&callback=jsonp1192244621103`
+`search` with API Version 6 for packages containing `cookie` AND `milk`::
+  `/rpc/?v=6&type=search&arg=cookie%20milk`
+`search` with API Version 6 for packages containing `cookie milk`::
+  `/rpc/?v=6&type=search&arg="cookie milk"`
 `info`::
   `/rpc/?v=5&type=info&arg[]=foobar`
 `info` with multiple packages::
diff --git a/web/lib/aurjson.class.php b/web/lib/aurjson.class.php
index 0ac586fe..a3224e57 100644
--- a/web/lib/aurjson.class.php
+++ b/web/lib/aurjson.class.php
@@ -80,7 +80,7 @@ class AurJSON {
 		if (isset($http_data['v'])) {
 			$this->version = intval($http_data['v']);
 		}
-		if ($this->version < 1 || $this->version > 5) {
+		if ($this->version < 1 || $this->version > 6) {
 			return $this->json_error('Invalid version specified.');
 		}
 
@@ -140,7 +140,7 @@ class AurJSON {
 	}
 
 	/*
-	 * Check if an IP needs to be  rate limited.
+	 * Check if an IP needs to be rate limited.
 	 *
 	 * @param $ip IP of the current request
 	 *
@@ -192,7 +192,7 @@ class AurJSON {
 		$value = get_cache_value('ratelimit-ws:' . $ip, $status);
 		if (!$status || ($status && $value < $deletion_time)) {
 			if (set_cache_value('ratelimit-ws:' . $ip, $time, $window_length) &&
-			    set_cache_value('ratelimit:' . $ip, 1, $window_length)) {
+				set_cache_value('ratelimit:' . $ip, 1, $window_length)) {
 				return;
 			}
 		} else {
@@ -370,7 +370,7 @@ class AurJSON {
 		} elseif ($this->version >= 2) {
 			if ($this->version == 2 || $this->version == 3) {
 				$fields = implode(',', self::$fields_v2);
-			} else if ($this->version == 4 || $this->version == 5) {
+			} else if ($this->version >= 4 && $this->version <= 6) {
 				$fields = implode(',', self::$fields_v4);
 			}
 			$query = "SELECT {$fields} " .
@@ -472,6 +472,33 @@ class AurJSON {
 		return array('ids' => $id_args, 'names' => $name_args);
 	}
 
+	/*
+	 * Prepare a WHERE statement for each keyword: append $func($keyword)
+	 * separated by $delim. Each keyword is sanitized as wildcards before
+	 * it's passed to $func.
+	 *
+	 * @param $delim Delimiter to use in the middle of two keywords.
+	 * @param $keywords Array of keywords to prepare.
+	 * @param $func A function that returns a string. This value is concatenated.
+	 *
+	 * @return A WHERE condition statement of keywords separated by $delim.
+	 */
+	private function join_where($delim, $keywords, $func) {
+		// Applied to each item to concatenate our entire statement.
+		$reduce_func = function($carry, $item) use(&$func) {
+			array_push($carry, $func($item));
+			return $carry;
+		};
+
+		// Manual array_reduce with a local lambda.
+		$acc = array(); // Initial
+		foreach ($keywords as &$keyword) {
+			$acc += $reduce_func($acc, $keyword);
+		}
+
+		return join(" $delim ", $acc);
+	}
+
 	/*
 	 * Performs a fulltext mysql search of the package database.
 	 *
@@ -492,13 +519,36 @@ class AurJSON {
 			if (strlen($keyword_string) < 2) {
 				return $this->json_error('Query arg too small.');
 			}
-			$keyword_string = $this->dbh->quote("%" . addcslashes($keyword_string, '%_') . "%");
 
 			if ($search_by === 'name') {
-				$where_condition = "(Packages.Name LIKE $keyword_string)";
+				if ($this->version >= 6) {
+					$keywords = preg_split('/"([^"]*)"|\h+/', $keyword_string, -1, 
+						PREG_SPLIT_NO_EMPTY|PREG_SPLIT_DELIM_CAPTURE);
+					$func = function($keyword) {
+						$str = $this->dbh->quote("%" . addcslashes($keyword, '%_') . "%");
+						return "(Packages.Name LIKE $str)";
+					};
+					$where_condition = $this->join_where("AND", $keywords, $func);
+				} else {
+					$keyword_string = $this->dbh->quote(
+						"%" . addcslashes($keyword_string, '%_') . "%");
+					$where_condition = "(Packages.Name LIKE $keyword_string)";
+				}
 			} else if ($search_by === 'name-desc') {
-				$where_condition = "(Packages.Name LIKE $keyword_string OR ";
-				$where_condition .= "Description LIKE $keyword_string)";
+				if ($this->version >= 6) {
+					$keywords = preg_split('/"([^"]*)"|\h+/', $keyword_string, -1, 
+						PREG_SPLIT_NO_EMPTY|PREG_SPLIT_DELIM_CAPTURE);
+					$func = function($keyword) {
+						$str = $this->dbh->quote("%" . addcslashes($keyword, '%_') . "%");
+						return "(Packages.Name LIKE $str OR Description LIKE $str)";
+					};
+					$where_condition = $this->join_where("AND", $keywords, $func);
+				} else {
+					$keyword_string = $this->dbh->quote(
+						"%" . addcslashes($keyword_string, '%_') . "%");
+					$where_condition = "(Packages.Name LIKE $keyword_string ";
+					$where_condition .= "OR Description LIKE $keyword_string)";
+				}
 			}
 		} else if ($search_by === 'maintainer') {
 			if (empty($keyword_string)) {
-- 
2.20.1