Make suggestions work in offline search

1 files changed, 38 insertions, 1 deletions

diff --git a/app/src/main/java/github/daneren2005/dsub/domain/SearchCritera.java b/app/src/main/java/github/daneren2005/dsub/domain/SearchCritera.java
index 20d46aa0..12c641f2 100644
--- a/app/src/main/java/github/daneren2005/dsub/domain/SearchCritera.java
+++ b/app/src/main/java/github/daneren2005/dsub/domain/SearchCritera.java
@@ -18,6 +18,8 @@
  */
 package github.daneren2005.dsub.domain;
 
+import java.util.regex.Pattern;
+
 /**
  * The criteria for a music search.
  *
@@ -29,6 +31,7 @@ public class SearchCritera {
     private final int artistCount;
     private final int albumCount;
     private final int songCount;
+    private Pattern pattern;
 
     public SearchCritera(String query, int artistCount, int albumCount, int songCount) {
         this.query = query;
@@ -52,4 +55,38 @@ public class SearchCritera {
     public int getSongCount() {
         return songCount;
     }
-}
\ No newline at end of file
+
+    /**
+     * Returns and caches a pattern instance that can be used to check if a
+     * string matches the query.
+     */
+    public Pattern getPattern() {
+
+      // If the pattern wasn't already cached, create a new regular expression
+      // from the search string :
+      //  * Surround the search string with ".*" (match anything)
+      //  * Replace spaces and wildcard '*' characters with ".*"
+      //  * All other characters are properly quoted
+      if (this.pattern == null) {
+        String regex = ".*";
+        String currentPart = "";
+        for (int i = 0; i < query.length(); i++) {
+          char c = query.charAt(i);
+          if (c == '*' || c == ' ') {
+            regex += Pattern.quote(currentPart);
+            regex += ".*";
+            currentPart = "";
+          } else {
+            currentPart += c;
+          }
+        }
+        if (currentPart.length() > 0) {
+          regex += Pattern.quote(currentPart);
+        }
+        regex += ".*";
+        this.pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);
+      }
+
+      return this.pattern;
+    }
+}