1 files changed, 55 insertions, 15 deletions
diff --git a/src/view/options.ts b/src/view/options.ts
index 31fd631..0782fe4 100644
--- a/src/view/options.ts
+++ b/src/view/options.ts
@@ -1,30 +1,70 @@
+import * as Chord from 'chord'
+
+// Model version: upgrade whenever the model is updated. Options are loaded
+// only if versions match.
+const version = '2'
+
 export interface Model {
-  major: boolean
-  minor: boolean
-  seventh: boolean
-  minorSeventh: boolean
-  majorSeventh: boolean
+  major: Chord.Chords
+  minor: Chord.Chords
+  seventh: Chord.Chords
+  minorSeventh: Chord.Chords
+  majorSeventh: Chord.Chords
   bpm: number
   beatsPerChord: number
 }
 
 let init: Model = {
-  major: true,
-  minor: false,
-  seventh: false,
-  minorSeventh: false,
-  majorSeventh: false,
+  major: new Set(Chord.plains),
+  minor: new Set(),
+  seventh: new Set(),
+  minorSeventh: new Set(),
+  majorSeventh: new Set(),
   bpm: 90,
   beatsPerChord: 4
 }
 
-let key: string = 'options'
-
 export function load(): Model {
-  let str = localStorage[key]
-  return str && JSON.parse(str) || init
+  let storedVersion = localStorage['version']
+
+  if (storedVersion === undefined || storedVersion !== version) {
+    return init
+  } else {
+    let str = localStorage['options']
+    return str && fromString(str) || init
+  }
 }
 
 export function save(options: Model): void {
-  localStorage[key] = JSON.stringify(options)
+  localStorage['version'] = version
+  localStorage['options'] = toString(options)
+}
+
+function toString(o: Model): string {
+  return JSON.stringify({
+    major: [...o.major],
+    minor: [...o.minor],
+    seventh: [...o.seventh],
+    minorSeventh: [...o.minorSeventh],
+    majorSeventh: [...o.majorSeventh],
+    bpm: o.bpm,
+    beatsPerChord: o.beatsPerChord
+  })
+}
+
+function fromString(str: string): Model | undefined {
+  const o = JSON.parse(str)
+  if (o === undefined) {
+    return undefined
+  } else {
+    return {
+      major: new Set(o.major),
+      minor: new Set(o.minor),
+      seventh: new Set(o.seventh),
+      minorSeventh: new Set(o.minorSeventh),
+      majorSeventh: new Set(o.majorSeventh),
+      bpm: o.bpm,
+      beatsPerChord: o.beatsPerChord
+    }
+  }
 }