Remove select callbacks and use observable instead

src/index.js

@@ -116,7 +116,7 @@ function load() {
 
   panzoom.start(svg);
   gameboard.start(svg);
-  recordSheet.start(startLocs, gameboard.getUnits(), gameboard.unSelect, gameboard.select);
+  recordSheet.start(startLocs, gameboard.getUnits());
 }
 
 document.querySelectorAll('.end-turn').forEach(el =>
@@ -158,14 +158,13 @@ gameboard.setDistanceCallback((count = '-') => {
 });
 
 gameboard.setProneFlagCallback(checked => proneToggle.checked = checked);
-gameboard.setSelectCallback(data => recordSheet.select(data));
 
 document.querySelectorAll('.end-move').forEach(el => el.addEventListener('click', () => {
   recordSheet.endMove();
   gameboard.endMove();
 }));
 
-document.querySelector('#fullscreen').addEventListener('click', e => {
+document.querySelector('#fullscreen').addEventListener('click', () => {
   if (!document.fullscreenElement) {
     document.documentElement.requestFullscreen();
   } else if (document.exitFullscreen) {

src/modules/gameboard.js

@@ -1,8 +1,9 @@
 import * as firingArc from './game/firing_arc.js';
 import * as sightLine from './game/sight_line.js';
 import * as soldier from './game/soldier.js';
+import { Observable } from "./observable";
 
-let svg, distanceCallback, proneFlagCallback, selectCallback,
+let svg, distanceCallback, proneFlagCallback,
   selected,
   placing = [];
 
@@ -74,6 +75,17 @@ function getSelected() {
   return svg.querySelector(`.counter.selected[data-allegiance][data-number]`);
 }
 
+function deselect() {
+  const selected = getSelected();
+  placing = [];
+
+  if (selected) {
+    selected.classList.remove(soldier.getSelectedClass());
+    clearSightLine();
+    firingArc.clipAll(svg);
+  }
+}
+
 function clearSightLine() {
   sightLine.setHexes([]);
   sightLine.clear();
@@ -159,7 +171,7 @@ function hasPreviousMoveInHistory(counter) {
 }
 
 function selectOffBoard() {
-  this.classList.contains(soldier.getSelectedClass()) ? unSelect() : select(this);
+  Observable.notify('select', this);
 }
 
 export function getUnits() {
@@ -174,10 +186,6 @@ export function setProneFlagCallback(callback) {
   proneFlagCallback = callback;
 }
 
-export function setSelectCallback(callback) {
-  selectCallback = callback;
-}
-
 export function start(el) {
   svg = el;
 
@@ -202,10 +210,10 @@ export function start(el) {
             placing.push(toPlace);
             getLockedSightLine(svg) ? updateSightLine(toPlace.parentElement) : drawSightLine(toPlace.parentElement, cell);
           } else {
-            unSelect();
+            deselect();
           }
         } else if (!occupant.classList.contains('clone')) {
-          select(occupant);
+          Observable.notify('select', occupant);
         } else {
           if (isClone(occupant).of(toPlace)) {
             if (hasPreviousMoveInHistory(occupant)) {
@@ -218,7 +226,7 @@ export function start(el) {
           placing.push(toPlace);
         }
       } else if (!toPlace && occupant) {
-        select(occupant);
+        Observable.notify('select', occupant);
       } else {
         console.log('removing cell contents');
         getCellContents(cell).forEach(el => el.remove());
@@ -234,7 +242,7 @@ export function start(el) {
           selector = `[data-allegiance="${allegiance}"][data-number="${number}"]`;
 
         svg.querySelectorAll(selector).forEach(el => el.remove());
-        selectCallback();
+        Observable.notify('select');
       }
     });
 
@@ -271,33 +279,23 @@ export function start(el) {
     });
   });
 
+  Observable.subscribe('select', select);
   console.log('gameboard.js loaded');
 }
 
-export function select(selected) {
-  unSelect();
-  let counter = soldier.getCounter(svg, selected);
+export function select(data) {
+  if (!data) return;
 
-  if (counter) {
-    firingArc.get(svg, counter).forEach(el => el.removeAttribute('clip-path'));
-  } else {
-    counter = soldier.createCounter(selected);
-  }
+  const counter = soldier.getCounter(svg, data) || soldier.createCounter(data);
+  const isSelected = counter.classList.contains(soldier.getSelectedClass());
+
+  deselect();
+
+  if (isSelected) return;
 
-  placing.push(counter);
   counter.classList.add(soldier.getSelectedClass());
-  selectCallback && selectCallback({ prone: soldier.hasProne(counter), ...counter.dataset });
-}
-
-export function unSelect() {
-  const selected = getSelected();
-  placing = [];
-
-  if (selected) {
-    getSelected().classList.remove(soldier.getSelectedClass());
-    clearSightLine();
-    firingArc.clipAll(svg);
-  }
+  firingArc.get(svg, counter).forEach(el => el.removeAttribute('clip-path'));
+  placing.push(counter);
 }
 
 export function endMove() {
@@ -305,7 +303,7 @@ export function endMove() {
 
   if (selected) {
     soldier.endMove(svg, selected);
-    unSelect();
+    deselect();
   }
 }
 

src/modules/observable.js

@@ -0,0 +1,19 @@
+const observers = {};
+
+export const Observable = Object.freeze({
+  notify: (event, data) => {
+    observers[event].forEach((observer) => observer(data))
+  },
+
+  subscribe: (event, func) => {
+    (observers[event] ??= []).push(func);
+  },
+
+  unsubscribe: (event, func) => {
+    [...observers[event] || []].forEach((observer, index) => {
+      if (observer === func) {
+        observers[event].splice(index, 1);
+      }
+    });
+  },
+});

src/modules/record_sheet.js

@@ -1,3 +1,5 @@
+import { Observable } from "./observable";
+
 const weapons = {
   rifle: {
     name: 'Rifle',
@@ -98,27 +100,19 @@ function createRecords(units) {
   return grouped;
 }
 
-function addEventListeners(unSelectCounter, selectCounter) {
+function getRecord({ dataset: { allegiance: al, number: n }}) {
+  const selector = `.soldier-record[data-number="${n}"][data-allegiance="${al}"]`;
+
+  return document.querySelector(selector);
+}
+
+function addEventListeners() {
   document.querySelectorAll('.soldier-record').forEach(el =>
-    el.addEventListener('click', () => {
-      if (el.classList.contains('selected')) {
-        el.classList.remove('selected');
-        unSelectCounter();
-        unSelect();
-      } else {
-        selectCounter(el);
-      }
-    })
+    el.addEventListener('click', () => Observable.notify('select', el))
   );
 }
 
-export function clear() {
-  document.querySelectorAll('#record-sheet .soldier-record').forEach(el => el.remove());
-  document.querySelector('#attacker-record .name').textContent = 'attacker';
-  document.querySelector('#defender-record .name').textContent = 'defender';
-}
-
-export function unSelect() {
+function deselect() {
   const selected = getSelected();
 
   if (selected) {
@@ -128,24 +122,28 @@ export function unSelect() {
   document.getElementById('toggle-prone-counter').checked = false;
 }
 
-export function getSelected() {
-  return document.querySelector('.soldier-record.selected');
+function clear() {
+  document.querySelectorAll('#record-sheet .soldier-record').forEach(el => el.remove());
+  document.querySelector('#attacker-record .name').textContent = 'attacker';
+  document.querySelector('#defender-record .name').textContent = 'defender';
 }
 
-export function select(data) {
-  unSelect();
+function select(data) {
+  const record = data && getRecord(data);
+  const isSelected = record?.classList.contains('selected');
 
-  if (!data) {
-    return;
-  }
+  deselect();
 
-  const { allegiance: al, number: n } = data,
-    selector = `.soldier-record[data-number="${n}"][data-allegiance="${al}"]`;
+  if (isSelected || !data) return;
 
-  document.querySelector(selector).classList.add('selected');
+  record.classList.add('selected');
   document.querySelector('#toggle-prone-counter').checked = data.prone;
 }
 
+export function getSelected() {
+  return document.querySelector('.soldier-record.selected');
+}
+
 export function endMove() {
   const selected = getSelected();
 
@@ -153,10 +151,10 @@ export function endMove() {
     selected.classList.toggle('movement-ended');
   }
 
-  unSelect();
+  deselect();
 }
 
-export function start(startLoc, units, gbUnSelect, gbSelect) {
+export function start(startLoc, units) {
   clear();
   const forces = createRecords(units);
 
@@ -171,5 +169,6 @@ export function start(startLoc, units, gbUnSelect, gbSelect) {
     forces[affiliation].forEach(r => records.appendChild(r));
   }
 
-  addEventListeners(gbUnSelect, gbSelect);
+  Observable.subscribe('select', select);
+  addEventListeners();
 }