From ea61e8f2d3870ec3d5cc5ced2fe797be44893c85 Mon Sep 17 00:00:00 2001
From: Peter Serwylo <peter@serwylo.com>
Date: Mon, 25 May 2015 16:20:56 +1000
Subject: [PATCH] Organised SwapState class, moved methods around to make more
 sense.

Put all of the step handling code in one place, added some comments to
make sense of the different parts of the claass and their
responsibilities.
---
 .../fdroid/fdroid/localrepo/SwapState.java    | 115 ++++++++++--------
 1 file changed, 65 insertions(+), 50 deletions(-)

diff --git a/F-Droid/src/org/fdroid/fdroid/localrepo/SwapState.java b/F-Droid/src/org/fdroid/fdroid/localrepo/SwapState.java
index ad458c57d..635676c8b 100644
--- a/F-Droid/src/org/fdroid/fdroid/localrepo/SwapState.java
+++ b/F-Droid/src/org/fdroid/fdroid/localrepo/SwapState.java
@@ -22,46 +22,6 @@ public class SwapState {
 
     private static final String SHARED_PREFERENCES = "swap-state";
 
-    public static final int STEP_INTRO       = 1;
-    public static final int STEP_SELECT_APPS = 2;
-    public static final int STEP_JOIN_WIFI   = 3;
-    public static final int STEP_SHOW_NFC    = 4;
-    public static final int STEP_WIFI_QR     = 5;
-
-
-    @NonNull
-    private final Context context;
-
-    @NonNull
-    private Set<String> appsToSwap;
-
-    private int step;
-
-    private SwapState(@NonNull Context context, @SwapStep int step, @NonNull Set<String> appsToSwap) {
-        this.context = context.getApplicationContext();
-        this.step = step;
-        this.appsToSwap = appsToSwap;
-    }
-
-    /**
-     * Current screen that the swap process is up to.
-     * Will be one of the SwapState.STEP_* values.
-     */
-    @SwapStep
-    public int getStep() {
-        return step;
-    }
-
-    public SwapState setStep(@SwapStep int step) {
-        this.step = step;
-        persistStep();
-        return this;
-    }
-
-    public Set<String> getAppsToSwap() {
-        return appsToSwap;
-    }
-
     private static final String KEY_STEP         = "step";
     private static final String KEY_APPS_TO_SWAP = "appsToSwap";
 
@@ -81,14 +41,79 @@ public class SwapState {
         return instance;
     }
 
+    @NonNull
+    private final Context context;
+
+    @NonNull
+    private Set<String> appsToSwap;
+
+    private SwapState(@NonNull Context context, @SwapStep int step, @NonNull Set<String> appsToSwap) {
+        this.context = context.getApplicationContext();
+        this.step = step;
+        this.appsToSwap = appsToSwap;
+    }
+
+    /**
+     * Where relevant, the state of the swap process will be saved to disk using preferences.
+     * Note that this is not always useful, for example saving the "current wifi network" is
+     * bound to cause trouble when the user opens the swap process again and is connected to
+     * a different network.
+     */
     private SharedPreferences persistence() {
         return context.getSharedPreferences(SHARED_PREFERENCES, Context.MODE_APPEND);
     }
 
+    // ==========================================================
+    //                 Manage the current step
+    // ("Step" refers to the current view being shown in the UI)
+    // ==========================================================
+
+    public static final int STEP_INTRO       = 1;
+    public static final int STEP_SELECT_APPS = 2;
+    public static final int STEP_JOIN_WIFI   = 3;
+    public static final int STEP_SHOW_NFC    = 4;
+    public static final int STEP_WIFI_QR     = 5;
+
+    private @SwapStep int step;
+
+    /**
+     * Current screen that the swap process is up to.
+     * Will be one of the SwapState.STEP_* values.
+     */
+    @SwapStep
+    public int getStep() {
+        return step;
+    }
+
+    public SwapState setStep(@SwapStep int step) {
+        this.step = step;
+        persistStep();
+        return this;
+    }
+
+    public @NonNull Set<String> getAppsToSwap() {
+        return appsToSwap;
+    }
+
     private void persistStep() {
         persistence().edit().putInt(KEY_STEP, step).commit();
     }
 
+    /**
+     * Ensure that we don't get put into an incorrect state, by forcing people to pass valid
+     * states to setStep. Ideally this would be done by requiring an enum or something to
+     * be passed rather than in integer, however that is harder to persist on disk than an int.
+     * This is the same as, e.g. {@link Context#getSystemService(String)}
+     */
+    @IntDef({STEP_INTRO, STEP_SELECT_APPS, STEP_JOIN_WIFI, STEP_SHOW_NFC, STEP_WIFI_QR})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface SwapStep {}
+
+
+    // ==========================================
+    //      Remember apps user wants to swap
+    // ==========================================
+
     private void persistAppsToSwap() {
         persistence().edit().putString(KEY_APPS_TO_SWAP, serializePackages(appsToSwap)).commit();
     }
@@ -143,16 +168,6 @@ public class SwapState {
         persistAppsToSwap();
     }
 
-    /**
-     * Ensure that we don't get put into an incorrect state, by forcing people to pass valid
-     * states to setStep. Ideally this would be done by requiring an enum or something to
-     * be passed rather than in integer, however that is harder to persist on disk than an int.
-     * This is the same as, e.g. {@link Context#getSystemService(String)}
-     */
-    @IntDef({STEP_INTRO, STEP_SELECT_APPS, STEP_JOIN_WIFI, STEP_SHOW_NFC, STEP_WIFI_QR})
-    @Retention(RetentionPolicy.SOURCE)
-    public @interface SwapStep {}
-
 
     // ==========================================
     //   Local repo stop/start/restart handling