parens handler + parser in progress

src/services/search/parser.js

@@ -0,0 +1,81 @@
+const AndExp = require('./expressions/and');
+const OrExp = require('./expressions/or');
+const NotExp = require('./expressions/not');
+const ExistsExp = require('./expressions/exists');
+const EqualsExp = require('./expressions/equals');
+const NoteCacheFulltextExp = require('./expressions/note_cache_fulltext');
+const NoteContentFulltextExp = require('./expressions/note_content_fulltext');
+
+function getFulltext(tokens, includingNoteContent) {
+    if (includingNoteContent) {
+        return [
+            new OrExp([
+                new NoteCacheFulltextExp(tokens),
+                new NoteContentFulltextExp(tokens)
+            ])
+        ]
+    }
+    else {
+        return [
+            new NoteCacheFulltextExp(tokens)
+        ]
+    }
+}
+
+function isOperator(str) {
+    return str.matches(/^[=<>*]+$/);
+}
+
+function getExpressions(tokens) {
+    const expressions = [];
+    let op = null;
+
+    for (let i = 0; i < tokens.length; i++) {
+        const token = tokens[i];
+
+        if (token === '#' || token === '@') {
+            continue;
+        }
+
+        if (Array.isArray(token)) {
+            expressions.push(getExpressions(token));
+        }
+        else if (token.startsWith('#') || token.startsWith('@')) {
+            const type = token.startsWith('#') ? 'label' : 'relation';
+
+            if (i < tokens.length - 2 && isOperator(tokens[i + 1])) {
+                expressions.push(new EqualsExp(type, token.substr(1), tokens[i + 1], tokens[i + 2]));
+
+                i += 2;
+            }
+            else {
+                expressions.push(new ExistsExp(type, token.substr(1)));
+            }
+        }
+        else if (['and', 'or'].includes(token.toLowerCase())) {
+            if (!op) {
+                op = token.toLowerCase();
+            }
+            else if (op !== token.toLowerCase()) {
+                throw new Error('Mixed usage of AND/OR - always use parenthesis to group AND/OR expressions.');
+            }
+        }
+        else if (isOperator(token)) {
+            throw new Error(`Misplaced or incomplete expression "${token}"`);
+        }
+        else {
+            throw new Error(`Unrecognized expression "${token}"`);
+        }
+
+        if (!op && expressions.length > 1) {
+            op = 'and';
+        }
+    }
+}
+
+function parse(fulltextTokens, expressionTokens, includingNoteContent) {
+    return AndExp.of([
+        ...getFulltext(fulltextTokens, includingNoteContent),
+        ...getExpressions(expressionTokens)
+    ]);
+}