From afc383c3d924b16ecd8fcf799be0117a802b231b Mon Sep 17 00:00:00 2001
From: Ian Renton <ian@ianrenton.com>
Date: Fri, 3 Oct 2025 13:53:23 +0100
Subject: [PATCH] Persist filters to local storage. Closes #22

---
 webassets/js/code.js | 50 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 41 insertions(+), 9 deletions(-)

diff --git a/webassets/js/code.js b/webassets/js/code.js
index d2b5231..ee9e426 100644
--- a/webassets/js/code.js
+++ b/webassets/js/code.js
@@ -185,6 +185,9 @@ function loadOptions() {
         $("#filters-container-2").append(generateFilterCard("Modes", "mode_type", options["mode_types"]));
         $("#filters-container-2").append(generateFilterCard("Sources", "source", options["sources"]));
 
+        // Load filter settings from settings storage
+        loadSettings();
+
         // Load spots and set up the timer
         loadSpots();
         setInterval(loadSpots, REFRESH_INTERVAL_SEC * 1000)
@@ -213,7 +216,7 @@ function generateFilterCard(displayName, filterQuery, options) {
     $card_body.append(`<h5 class='card-title'>${displayName}</h5>`);
     $p = $("<p class='card-text filter-card-text'>");
     options.forEach(o => {
-        $p.append(`<input type="checkbox" class="btn-check filter-button-${filterQuery}" name="options" id="filter-button-${filterQuery}-${o}" value="${o}" autocomplete="off" onClick="loadSpots()" checked><label class="btn btn-outline-primary" for="filter-button-${filterQuery}-${o}">${o}</label> `);
+        $p.append(`<input type="checkbox" class="btn-check filter-button-${filterQuery} storeable-checkbox" name="options" id="filter-button-${filterQuery}-${o}" value="${o}" autocomplete="off" onClick="filtersUpdated()" checked><label class="btn btn-outline-primary" for="filter-button-${filterQuery}-${o}">${o}</label> `);
     });
     $card_body.append($p);
     $card.append($card_body);
@@ -232,7 +235,7 @@ function generateBandsFilterCard(displayName, filterQuery, band_options) {
         // CSS doesn't like IDs with decimal points in, so we need to replace that in the same way as when we originally
         // queried the options endpoint and set our CSS.
         var cssFormattedBandName = o['name'] ? o['name'].replace('.', 'p') : "unknown";
-        $p.append(`<input type="checkbox" class="btn-check filter-button-${filterQuery}" name="options" id="filter-button-${filterQuery}-${o['name']}" value="${o['name']}" autocomplete="off" onClick="loadSpots()" checked><label class="btn btn-outline" id="filter-button-label-${filterQuery}-${cssFormattedBandName}" for="filter-button-${filterQuery}-${o['name']}">${o['name']}</label> `);
+        $p.append(`<input type="checkbox" class="btn-check filter-button-${filterQuery} storeable-checkbox" name="options" id="filter-button-${filterQuery}-${o['name']}" value="${o['name']}" autocomplete="off" onClick="filtersUpdated()" checked><label class="btn btn-outline" id="filter-button-label-${filterQuery}-${cssFormattedBandName}" for="filter-button-${filterQuery}-${o['name']}">${o['name']}</label> `);
     });
     $card_body.append($p);
     $card.append($card_body);
@@ -240,6 +243,12 @@ function generateBandsFilterCard(displayName, filterQuery, band_options) {
     return $col;
 }
 
+// Method called when any filter is changed to reload the spots and persist the filter settings.
+function filtersUpdated() {
+    loadSpots();
+    saveSettings();
+}
+
 // Update the refresh timing display
 function updateRefreshDisplay() {
     if (lastUpdateTime != null) {
@@ -275,14 +284,27 @@ function escapeHtml(str) {
     return str.replace(/[&<>"'`]/g, escapeCharacter);
 }
 
-// Startup
-$(document).ready(function() {
-    // Call loadOptions(), this will then trigger loading spots and setting up timers.
-    loadOptions();
-    // Update the refresh timing display every second
-    setInterval(updateRefreshDisplay, 1000);
+// Save settings to local storage
+function saveSettings() {
+    // Find all storeable UI elements, store a key of "element id:property name" mapped to the value of that
+    // property. For a checkbox, that's the "checked" property.
+    return $(".storeable-checkbox").each(function() {
+        localStorage.setItem($(this)[0].id + ":checked", $(this)[0].checked);
+    });
+}
 
-    // Event listeners
+// Load settings from local storage and set up the filter selectors
+function loadSettings() {
+    // Find all local storage entries and push their data to the corresponding UI element
+    Object.keys(localStorage).forEach(function(key) {
+        // Split the key back into an element ID and a property
+        var split = key.split(":");
+        $("#" + split[0]).prop(split[1], JSON.parse(localStorage.getItem(key)));
+    });
+}
+
+// Set up UI element event listeners, after the document is ready
+function setUpEventListeners() {
     $("#status-button").click(function() {
         // If we are going to display status, load the data for the status panel
         if (!$("#status-area").is(":visible")) {
@@ -301,4 +323,14 @@ $(document).ready(function() {
         $("#filters-button").button("toggle");
         $("#filters-area").hide();
     });
+}
+
+// Startup
+$(document).ready(function() {
+    // Call loadOptions(), this will then trigger loading spots and setting up timers.
+    loadOptions();
+    // Update the refresh timing display every second
+    setInterval(updateRefreshDisplay, 1000);
+    // Set up event listeners
+    setUpEventListeners();
 });
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