marc xpath parser and compiler. needs more testing

git-svn-id: svn://svn.open-ils.org/ILS/trunk@10553 dcc99617-32d9-48b4-a31d-7c20da2025e4

diff --git a/Open-ILS/web/js/dojo/openils/MarcXPathParser.js b/Open-ILS/web/js/dojo/openils/MarcXPathParser.js
new file mode 100644 (file)
index 0000000..579fc9a
--- /dev/null
+++ b/Open-ILS/web/js/dojo/openils/MarcXPathParser.js
@@ -0,0 +1,95 @@
+/* ---------------------------------------------------------------------------
+ * Copyright (C) 2008  Georgia Public Library Service
+ * Bill Erickson <erickson@esilibrary.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * ---------------------------------------------------------------------------
+ */
+
+if(!dojo._hasResource["openils.MarcXPathParser"]) {
+    dojo._hasResource["openils.MarcXPathParser"] = true;
+    dojo.provide("openils.MarcXPathParser");
+
+    dojo.declare('openils.MarcXPathParser', null, {
+        /**
+          * Parse a marc xpath expression and return the breakdown of tags, subfields, and match offset
+          */
+        parse : function(expr) {
+            // this is about as simple as it gets. will need more 
+            // smarts if the expressions get more complicated
+            var tags = expr.match(/\d{3}/g);
+            var subfields = expr.match(/['"]([a-z]+)['"]/);
+            var offset = expr.match(/\[(\d+)\]$/);
+            return {
+                tags : tags,
+                subfields : (subfields) ? subfields[1].split('') : [],
+                offset : (offset) ? offset[1] : null
+            }
+        },
+
+        /**
+          * Creates an XPath expression from a set of tags/subfields/offset
+          */
+        compile : function(parts) {
+            var str = '//*[';
+            for(var i = 0; i < parts.tags.length; i++) {
+                var tag = parts.tags[i];
+                if(i > 0)
+                    str += ' or ';
+                str += '@tag="'+tag+'"';
+            }
+            str += ']';
+            if(parts.subfields.length > 0) {
+                str += '/*[';
+                if(parts.subfields.length == 1) {
+                    str += '@code="' + parts.subfields[0] + '"]';
+                } else {
+                    str += 'contains("' + parts.subfields.join('') +'",@code)]';
+                }
+            }
+            if(parts.offset)
+                str += '[' + parts.offset + ']';
+            return str;
+        }
+    });
+}
+
+
+openils.MarcXPathParser.test = function() {
+    var expr = [
+        '//*[@tag="300"]/*[@code="a"][1]',
+        '//*[@tag="020"]/*[@code="a"]',
+        '//*[@tag="022"]/*[@code="a"]',
+        '//*[@tag="020" or @tag="022"]/*[@code="c"][1]',
+        '//*[@tag="001"]',
+        '//*[@tag="901"]/*[@code="a"]',
+        '//*[@tag="901"]/*[@code="b"]',
+        '//*[@tag="901"]/*[@code="c"]',
+        '//*[@tag="260"]/*[@code="b"][1]',
+        '//*[@tag="250"]/*[@code="a"][1]',
+        '//*[@tag="245"]/*[contains("abcmnopr",@code)]',
+        '//*[@tag="260"]/*[@code="c"][1]',
+        '//*[@tag="100" or @tag="110" or @tag="113"]/*[contains("ad",@code)]',
+        '//*[@tag="240"]/*[@code="l"][1]'
+    ];
+
+    var parser = new openils.MarcXPathParser();
+
+    for(var i = 0; i < expr.length; i++) {
+        var vals = parser.parse(expr[i]);
+        console.log(expr[i]);
+        console.log(vals.tags);
+        console.log(vals.subfields);
+        console.log(vals.offset);
+        console.log(parser.compile(vals));
+    }
+};
+