Feat/UI and or toggle

API.md

@@ -486,9 +486,11 @@ an `active` flag plus slider thresholds or selected categories.
 > Grammar, for reference only: a property path `section::subGroup::property`
 > followed by exactly one condition — `BETWEEN <low> AND <high>`,
 > `LOWER THAN <a> OR GREATER THAN <b>` (always two-sided — there is **no**
-> standalone `LOWER THAN`), or `IN [value1, value2]` — with clauses combined by
-> `AND` / `OR` / `NOT` and grouped in parentheses. There are no `<`, `>`, or `=`
-> operators.
+> standalone `LOWER THAN`), `IN [value1, value2]`, or the unary `IS MISSING`
+> (true when the property is absent/empty or belongs to the other element type;
+> emitted automatically by the filter panel's non-strict AND join) — with
+> clauses combined by `AND` / `OR` / `NOT` and grouped in parentheses. There are
+> no `<`, `>`, or `=` operators.
 
 ---
 

ARCHITECTURE.md

@@ -56,7 +56,7 @@ Business logic and UI:
 - `io.js` — `IOManager`: Excel/JSON loading, export (JSON / PNG / SVG), data
   preprocessing, Excel template generation
 - `ui.js` — loading overlays, UI enable/disable, notifications
-- `query.js` — query DSL with an AST (AND/OR/NOT, BETWEEN, IN, comparisons)
+- `query.js` — query DSL with an AST (AND/OR/NOT, BETWEEN, IN, IS MISSING, comparisons)
 - `ui_components.js` — filter UI (dropdown checklists, invertible range sliders), tooltips
 - `ui_style_div.js` — the styling panel (node/edge styles, badges, edge flow, density heatmap)
 - `metrics.js` — `NetworkMetrics`: degree/betweenness/closeness/eigenvector centrality, PageRank

CHANGELOG.md

@@ -1,5 +1,14 @@
 # Changelog
 
+## 1.15.4 — 2026-07-01
+
+Saved graph files load unchanged; older files default the two new per-view settings to the previous behavior (OR, non-strict).
+
+### Features
+
+* **OR / AND filter combination.** The filter panel (under ⚙ Details) can now combine active filters with **AND** as well as the default **OR**. AND counts only the filters you have actually narrowed, so switching modes while everything is at its default leaves the graph unchanged instead of emptying it. A **Complete cases only** option additionally hides elements that are missing any of those filters (evaluated per element type). The join mode and complete-cases flag are saved per workspace view in exported JSON.
+* Added an `IS MISSING` query-DSL operator — true when a property is absent/empty or belongs to the other element type — used to express the non-strict AND join. The query-editor help, guided tour, and API grammar reference now document it.
+
 ## 1.15.1 — 2026-06-17
 
 Saved graph files load unchanged — this release is bug fixes only.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "graph-lens-lite",
-  "version": "1.15.3",
+  "version": "1.15.4",
   "main": "src/package/electron_app.js",
   "description": "Visualise and explore property graphs in a lightweight desktop app.",
   "homepage": "https://github.com/Delta4AI/GraphLensLite",

src/config.js

@@ -1,7 +1,7 @@
 /**
  * Defaults for the graph, layouts and UI
  */
-const VERSION = "1.15.3";
+const VERSION = "1.15.4";
 
 const DEFAULTS = {
   NODE: {

src/graph/layout.js

@@ -706,6 +706,10 @@ class GraphLayoutManager {
       filters: structuredClone(this.cache.data.filterDefaults),
       isCustom: true, // All layouts are position-based
       query: undefined,
+      // How active filters combine (see updateQueryTextArea) and whether AND
+      // requires complete cases. Persisted per view via the workspace JSON.
+      filterJoinMode: 'OR',
+      filterStrict: false,
       hideDisconnectedNodes: false,
       // Per-view styles
       nodeStyles: new Map(),

src/managers/io.js

@@ -1,5 +1,5 @@
 /* global ExcelJS */ // loaded as a global via vendored src/lib/exceljs.min.js script tag
 import { DEFAULTS, CFG, VERSION } from '../config.js';
 import { StaticUtilities } from '../utilities/static.js';
 import { buildDataTable } from '../utilities/data_editor.js';
 import { EXPORT_SCALES } from '../utilities/export_scale.js';
@@ -1423,7 +1423,7 @@
           const filtersMap = new Map(Object.entries(layout.filters));
 
           // Restore Sets within each filter value
           for (const [propId, filterValue] of filtersMap.entries()) {
             if (filterValue.categories && Array.isArray(filterValue.categories)) {
               filterValue.categories = new Set(filterValue.categories);
             }
@@ -1467,7 +1467,7 @@
       const filterDefaultsMap = new Map(Object.entries(jsonContent.filterDefaults));
 
       // Restore Sets within each filter default value
       for (const [propId, filterValue] of filterDefaultsMap.entries()) {
         if (filterValue.categories && Array.isArray(filterValue.categories)) {
           filterValue.categories = new Set(filterValue.categories);
         }
@@ -2417,6 +2417,10 @@
         filters: this.parseFiltersAsMap(layout.filters),
         isCustom: layout.isCustom || false,
         query: layout['query'] || undefined,
+        // Per-view filter-join settings; default for pre-1.15.4 files that
+        // predate them (OR / non-strict = the historical behavior).
+        filterJoinMode: layout.filterJoinMode === 'AND' ? 'AND' : 'OR',
+        filterStrict: layout.filterStrict === true,
         // Per-view styles - check if already Maps
         hideDisconnectedNodes: layout.hideDisconnectedNodes || false,
         nodeStyles: