Optionally show surrounding context during search

opengrok-indexer/src/main/java/org/opengrok/indexer/search/Results.java

@@ -141,13 +141,13 @@ private static Reader getXrefReader(
     /**
      * Prints out results in html form. The following search helper fields are
      * required to be properly initialized: <ul>
-     * <li>{@link SearchHelper#dataRoot}</li>
-     * <li>{@link SearchHelper#contextPath}</li>
-     * <li>{@link SearchHelper#searcher}</li> <li>{@link SearchHelper#hits}</li>
-     * <li>{@link SearchHelper#historyContext} (ignored if {@code null})</li>
-     * <li>{@link SearchHelper#sourceContext} (ignored if {@code null})</li>
-     * <li>{@link SearchHelper#summarizer} (if sourceContext is not
-     * {@code null})</li> <li>{@link SearchHelper#sourceRoot} (if
+     * <li>{@link SearchHelper#getDataRoot()}</li>
+     * <li>{@link SearchHelper#getContextPath()}</li>
+     * <li>{@link SearchHelper#getSearcher()}</li> <li>{@link SearchHelper#getHits()}</li>
+     * <li>{@link SearchHelper#getHistoryContext()} (ignored if {@code null})</li>
+     * <li>{@link SearchHelper#getSourceContext()} (ignored if {@code null})</li>
+     * <li>{@link SearchHelper#getSummarizer()} (if sourceContext is not
+     * {@code null})</li> <li>{@link SearchHelper#getSourceRoot()} (if
      * sourceContext or historyContext is not {@code null})</li> </ul>
      *
      * @param out write destination
@@ -271,9 +271,9 @@ private static void printPlain(PrintPlainFinalArgs fargs, Document doc,
 
         fargs.shelp.getSourceContext().toggleAlt();
 
-        boolean didPresentNew = fargs.shelp.getSourceContext().getContext2(fargs.env,
+        boolean didPresentNew = fargs.shelp.getSourceContext().getContext2(
             fargs.shelp.getSearcher(), docId, fargs.out, fargs.xrefPrefix,
-            fargs.morePrefix, true, fargs.tabSize);
+            fargs.morePrefix, fargs.shelp.getLimitedContextArgs(), fargs.tabSize);
 
         if (!didPresentNew) {
             /*

opengrok-indexer/src/main/java/org/opengrok/indexer/search/context/Context.java

@@ -47,6 +47,7 @@
 import org.opengrok.indexer.search.Hit;
 import org.opengrok.indexer.search.QueryBuilder;
 import org.opengrok.indexer.util.IOUtils;
+import org.opengrok.indexer.web.QueryParameters;
 import org.opengrok.indexer.web.Util;
 
 /**
@@ -112,26 +113,19 @@ public boolean isEmpty() {
     /**
      * Look for context for this instance's initialized query in a search result
      * {@link Document}, and output according to the parameters.
-     * @param env required environment
      * @param searcher required search that produced the document
      * @param docId document ID for producing context
      * @param dest required target to write
      * @param urlPrefix prefix for links
      * @param morePrefix optional link to more... page
-     * @param limit a value indicating if the number of matching lines should be
-     * limited. N.b. unlike
-     * {@link #getContext(java.io.Reader, java.io.Writer, java.lang.String, java.lang.String, java.lang.String,
-     * org.opengrok.indexer.analysis.Definitions, boolean, boolean, java.util.List, org.opengrok.indexer.analysis.Scopes)},
-     * the {@code limit} argument will not be interpreted w.r.t.
-     * {@link RuntimeEnvironment#isQuickContextScan()}.
+     * @param contextArgs a value specifying how much context to show
      * @param tabSize optional positive tab size that must accord with the value
      * used when indexing or else postings may be wrongly shifted until
      * re-indexing
      * @return Did it get any matching context?
      */
-    public boolean getContext2(RuntimeEnvironment env, IndexSearcher searcher,
-        int docId, Appendable dest, String urlPrefix, String morePrefix,
-        boolean limit, int tabSize) {
+    public boolean getContext2(IndexSearcher searcher, int docId, Appendable dest,
+            String urlPrefix, String morePrefix, ContextArgs contextArgs, int tabSize) {
 
         if (isEmpty()) {
             return false;
@@ -178,35 +172,29 @@ public boolean getContext2(RuntimeEnvironment env, IndexSearcher searcher,
 
         String path = doc.get(QueryBuilder.PATH);
         String pathE = Util.uriEncodePath(path);
-        String urlPrefixE = urlPrefix == null ? "" : Util.uriEncodePath(urlPrefix);
-        String moreURL = morePrefix == null ? null : Util.uriEncodePath(morePrefix) + pathE + "?" + queryAsURI;
+        String urlPrefixE = urlPrefix == null ? "" : Util.uriEncodePath(
+            urlPrefix);
+        String moreURL = morePrefix == null ? null : Util.uriEncodePath(morePrefix) + pathE + "?" +
+                QueryParameters.CONTEXT_SURROUND_PARAM_EQ + contextArgs.getContextSurround() +
+                "&" + queryAsURI;
 
-        ContextArgs args = new ContextArgs(env.getContextSurround(), env.getContextLimit());
-        /*
-         * Lucene adds to the following value in FieldHighlighter, so avoid
-         * integer overflow by not using Integer.MAX_VALUE -- Short is good
-         * enough.
-         */
-        int linelimit = limit ? args.getContextLimit() : Short.MAX_VALUE;
-
-        ContextFormatter formatter = new ContextFormatter(args);
+        ContextFormatter formatter = new ContextFormatter(contextArgs);
         formatter.setUrl(urlPrefixE + pathE);
         formatter.setDefs(tags);
         formatter.setScopes(scopes);
         formatter.setMoreUrl(moreURL);
-        formatter.setMoreLimit(linelimit);
 
-        OGKUnifiedHighlighter uhi = new OGKUnifiedHighlighter(env, searcher, anz);
+        OGKUnifiedHighlighter uhi = new OGKUnifiedHighlighter(searcher, anz);
         uhi.setBreakIterator(StrictLineBreakIterator::new);
         uhi.setFormatter(formatter);
         uhi.setTabSize(tabSize);
+        uhi.setContextArgs(contextArgs);
 
         try {
             List<String> fieldList = qbuilder.getContextFields();
             String[] fields = fieldList.toArray(new String[0]);
 
-            String res = uhi.highlightFieldsUnion(fields, query, docId,
-                linelimit);
+            String res = uhi.highlightFieldsUnion(fields, query, docId);
             if (res != null) {
                 dest.append(res);
                 return true;

opengrok-indexer/src/main/java/org/opengrok/indexer/search/context/ContextArgs.java

@@ -27,6 +27,13 @@
  * to producing context presentations.
  */
 public class ContextArgs {
+    /**
+     * The maximum number of lines of surrounding context in a single direction
+     * to allow during a search. If there is sufficient content both preceding
+     * and following a hit, then the total context might be twice this value.
+     */
+    public static final short MAX_CONTEXT_SURROUND = 4;
+
     /** Not Lucene-related, so {@code int} does fine. */
     private static final int CONTEXT_WIDTH = 100;