Refactor Chapter Ordering Logic20171015

The bug impacting the CCB integration was due to the "Introduction"
chapter having a higher "score" than every other chapter. It was a
mistake to use Score to compared chapter progress, particularly since
there are more chapters than scores.

This change gathers the chapter ordering logic, which was scattered
throughout the code into a new Chapters enum. Playlist and Chapter now
use Chapters as a key, instead of loose strings. Same for the
ProgressReporter interface.

1 files changed, 46 insertions, 0 deletions

diff --git a/src/main/java/com/p4square/grow/model/Chapters.java b/src/main/java/com/p4square/grow/model/Chapters.java
new file mode 100644
index 0000000..175b6fb
--- /dev/null
+++ b/src/main/java/com/p4square/grow/model/Chapters.java
@@ -0,0 +1,46 @@
+package com.p4square.grow.model;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import java.util.Optional;
+
+/**
+ * The chapters of the training section.
+ */
+public enum Chapters {
+    INTRODUCTION,
+    SEEKER,
+    BELIEVER,
+    DISCIPLE,
+    TEACHER,
+    LEADER;
+
+    /**
+     * A case-insensitive version of Chapters.valueOf().
+     */
+    @JsonCreator
+    public static Chapters fromString(String s) {
+        return valueOf(s.toUpperCase());
+    }
+
+    @JsonValue
+    public String identifier() {
+        return toString().toLowerCase();
+    }
+
+    /**
+     * Convert the Chapter to a score, if possible.
+     */
+    public Optional<Double> toScore() {
+        switch (this) {
+            case SEEKER:
+            case BELIEVER:
+            case DISCIPLE:
+            case TEACHER:
+                return Optional.of(Score.numericScore(this.toString()));
+            default:
+                return Optional.empty();
+        }
+    }
+}