1 files changed, 87 insertions, 0 deletions
diff --git a/lib/exTpl/Scanner.php b/lib/exTpl/Scanner.php
new file mode 100644
index 0000000..76cbc01
--- /dev/null
+++ b/lib/exTpl/Scanner.php
@@ -0,0 +1,87 @@
+<?php
+/**
+ * Scanner.php - template parser lexical scanner
+ *
+ * Simple wrapper class around the Zend engine's lexical scanner. It
+ *  automatically skips whitespace.
+ *
+ * @copyright 2013  Elmar Ludwig
+ * @license GPL2 or any later version
+ */
+namespace exTpl;
+
+class Scanner
+{
+    private array $tokens;
+    private mixed $token_type;
+    private mixed $token_value;
+
+    /**
+     * Initializes a new Scanner instance for the given text.
+     *
+     * @param string $text string to parse
+     */
+    public function __construct(string $text)
+    {
+        $this->tokens = token_get_all('<?php ' . $text);
+    }
+
+    /**
+     * Advances the scanner to the next token and returns its token type.
+     * The valid token types are those defined for token_get_all() in the
+     * PHP documentation. Returns false when the end of input is reached.
+     */
+    public function nextToken(): mixed
+    {
+        do {
+            $token = next($this->tokens);
+            $key   = key($this->tokens);
+
+            // FIXME this workaround should be dropped
+            while (
+                $token && $token[0] === T_STRING
+                && isset($this->tokens[$key + 2])
+                && $this->tokens[++$key] === '-'
+                && $this->tokens[++$key][0] === T_STRING
+            ) {
+                $token[1] .= '-' . $this->tokens[$key][1];
+                next($this->tokens);
+                next($this->tokens);
+            }
+        } while (is_array($token) && $token[0] === T_WHITESPACE);
+
+        if (is_string($token) || $token === false) {
+            $this->token_type  = $token;
+            $this->token_value = null;
+        } else {
+            $this->token_type = $token[0];
+
+            $this->token_value = match ($token[0]) {
+                T_CONSTANT_ENCAPSED_STRING => stripcslashes(substr($token[1], 1, -1)),
+                T_DNUMBER => (double) $token[1],
+                T_LNUMBER => (int) $token[1],
+                default => $token[1],
+            };
+        }
+
+        return $this->token_type;
+    }
+
+    /**
+     * Returns the current token type. The valid token types are
+     * those defined for token_get_all() in the PHP documentation.
+     */
+    public function tokenType(): mixed
+    {
+        return $this->token_type;
+    }
+
+    /**
+     * Returns the current token value if the token type supports
+     * a value (T_STRING, T_LNUMBER etc.). Returns null otherwise.
+     */
+    public function tokenValue(): mixed
+    {
+        return $this->token_value;
+    }
+}