Light Boolean search implementation (#1828)

* Light Boolean search implementation

"Hello intitle:World OR date:P1D example"
https://github.com/FreshRSS/FreshRSS/issues/879

* Doc Boolean search

* Doc typos

1 files changed, 55 insertions, 0 deletions

diff --git a/app/Models/BooleanSearch.php b/app/Models/BooleanSearch.php
new file mode 100644
index 000000000..6e016f7e9
--- /dev/null
+++ b/app/Models/BooleanSearch.php
@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * Contains Boolean search from the search form.
+ */
+class FreshRSS_BooleanSearch {
+
+	private $raw_input = '';
+	private $searches = array();
+
+	public function __construct($input) {
+		$input = trim($input);
+		if ($input == '') {
+			return;
+		}
+		$this->raw_input = $input;
+
+		$input = preg_replace('/:&quot;(.*?)&quot;/', ':"\1"', $input);
+		$splits = preg_split('/\b(OR)\b/i', $input, -1, PREG_SPLIT_DELIM_CAPTURE);
+
+		$segment = '';
+		$ns = count($splits);
+		for ($i = 0; $i < $ns; $i++) {
+			$segment = $segment . $splits[$i];
+			if (trim($segment) == '' || strcasecmp($segment, 'OR') === 0) {
+				$segment = '';
+			} else {
+				$quotes = substr_count($segment, '"') + substr_count($segment, '&quot;');
+				if ($quotes % 2 === 0) {
+					$segment = trim($segment);
+					if ($segment != '') {
+						$this->searches[] = new FreshRSS_Search($segment);
+					}
+					$segment = '';
+				}
+			}
+		}
+		$segment = trim($segment);
+		if ($segment != '') {
+			$this->searches[] = new FreshRSS_Search($segment);
+		}
+	}
+
+	public function searches() {
+		return $this->searches;
+	}
+
+	public function __toString() {
+		return $this->getRawInput();
+	}
+
+	public function getRawInput() {
+		return $this->raw_input;
+	}
+}