(search) Add view for showing mutual links between two websites

code/api/assistant-api/src/main/java/nu/marginalia/assistant/client/model/SimilarDomain.java

@@ -36,6 +36,10 @@ public record SimilarDomain(EdgeUrl url,
         BIDIRECTIONAL,
         NONE;
 
+        public boolean isLinked() {
+            return this != NONE;
+        }
+
         public static LinkType find(boolean linkStod,
                                     boolean linkDtos) {
             if (linkDtos && linkStod)

code/services-application/search-service/src/main/java/nu/marginalia/search/SearchOperator.java

@@ -85,6 +85,14 @@ public class SearchOperator {
 
         return searchQueryService.getResultsFromQuery(queryResponse);
     }
+
+    public List<UrlDetails> doLinkSearch(Context context, String source, String dest) {
+        var queryParams = paramFactory.forLinkSearch(source, dest);
+        var queryResponse = queryClient.search(context, queryParams);
+
+        return searchQueryService.getResultsFromQuery(queryResponse);
+    }
+
     public DecoratedSearchResults doSearch(Context ctx, SearchParameters userParams) {
 
         Future<String> eval = searchUnitConversionService.tryEval(ctx, userParams.query());
@@ -181,4 +189,5 @@ public class SearchOperator {
     }
 
 
+
 }

code/services-application/search-service/src/main/java/nu/marginalia/search/SearchQueryParamFactory.java

@@ -69,4 +69,21 @@ public class SearchQueryParamFactory {
                 SearchSetIdentifier.NONE
         );
     }
+
+    public QueryParams forLinkSearch(String sourceDomain, String destDomain) {
+        return new QueryParams(STR."site:\{sourceDomain} links:\{destDomain}",
+                null,
+                List.of(),
+                List.of(),
+                List.of(),
+                List.of(),
+                SpecificationLimit.none(),
+                SpecificationLimit.none(),
+                SpecificationLimit.none(),
+                SpecificationLimit.none(),
+                List.of(),
+                new QueryLimits(100, 100, 100, 512),
+                SearchSetIdentifier.NONE
+        );
+    }
 }

code/services-application/search-service/src/main/java/nu/marginalia/search/SearchService.java

@@ -32,6 +32,7 @@ public class SearchService extends Service {
                          SearchErrorPageService errorPageService,
                          SearchAddToCrawlQueueService addToCrawlQueueService,
                          SearchSiteInfoService siteInfoService,
+                         SearchCrosstalkService crosstalkService,
                          SearchQueryService searchQueryService
                              ) {
         super(params);
@@ -55,6 +56,8 @@ public class SearchService extends Service {
         Spark.get("/public/site/:site", siteInfoService::handle);
         Spark.post("/public/site/:site", siteInfoService::handlePost);
 
+        Spark.get("/public/crosstalk/", crosstalkService::handle);
+
         Spark.exception(Exception.class, (e,p,q) -> {
             logger.error("Error during processing", e);
             errorPageService.serveError(Context.fromRequest(p), p, q);

code/services-application/search-service/src/main/java/nu/marginalia/search/svc/SearchCrosstalkService.java

@@ -0,0 +1,70 @@
+package nu.marginalia.search.svc;
+
+import com.google.inject.Inject;
+import nu.marginalia.client.Context;
+import nu.marginalia.renderer.MustacheRenderer;
+import nu.marginalia.renderer.RendererFactory;
+import nu.marginalia.search.SearchOperator;
+import nu.marginalia.search.model.UrlDetails;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import spark.Request;
+import spark.Response;
+
+import java.io.IOException;
+import java.sql.SQLException;
+import java.util.List;
+
+public class SearchCrosstalkService {
+    private static final Logger logger = LoggerFactory.getLogger(SearchCrosstalkService.class);
+    private final SearchOperator searchOperator;
+    private final MustacheRenderer<CrosstalkResult> renderer;
+
+    @Inject
+    public SearchCrosstalkService(SearchOperator searchOperator,
+                                  RendererFactory rendererFactory) throws IOException
+    {
+        this.searchOperator = searchOperator;
+        this.renderer = rendererFactory.renderer("search/site-info/site-crosstalk");
+    }
+
+    public Object handle(Request request, Response response) throws SQLException {
+        String domains = request.queryParams("domains");
+        String[] parts = StringUtils.split(domains, ',');
+
+        if (parts.length != 2) {
+            throw new IllegalArgumentException("Expected exactly two domains");
+        }
+
+        response.type("text/html");
+
+        for (int i = 0; i < parts.length; i++) {
+            parts[i] = parts[i].trim();
+        }
+
+        var resAtoB = searchOperator.doLinkSearch(Context.fromRequest(request), parts[0], parts[1]);
+        var resBtoA = searchOperator.doLinkSearch(Context.fromRequest(request), parts[1], parts[0]);
+
+        var model = new CrosstalkResult(parts[0], parts[1], resAtoB, resBtoA);
+
+        return renderer.render(model);
+    }
+
+
+
+    private record CrosstalkResult(String domainA,
+                                   String domainB,
+                                   List<UrlDetails> forward,
+                                   List<UrlDetails> backward)
+    {
+
+        public boolean isFocusDomain() {
+            return true; // Hack to get the search result templates behave well
+        }
+        public boolean hasBoth() {
+            return !forward.isEmpty() && !backward.isEmpty();
+        }
+
+    }
+}

code/services-application/search-service/src/main/resources/static/search/serp.scss

@@ -352,6 +352,15 @@ footer {
   align-items: start;
 }
 
+#crosstalk-view {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  grid-template-rows: auto 1fr;
+  grid-gap: 1ch;
+  align-content: start;
+  justify-content: start;
+  align-items: start;
+}
 
 #similar-view {
     display: grid;
@@ -405,7 +414,7 @@ footer {
 }
 
 @media (max-device-width: 900px) {
-  #similar-view {
+  #similar-view, #crosstalk-view {
     display: block;
     * {
       margin-bottom: 1ch;

code/services-application/search-service/src/main/resources/templates/search/site-info/site-crosstalk.hdb

@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="UTF-8">
+    <title>Marginalia Search - {{domainA}} and {{domainB}}</title>
+
+    <link rel="stylesheet" href="/serp.css" />
+    <link rel="search" type="application/opensearchdescription+xml" href="/opensearch.xml" title="Marginalia">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <meta name="robots" content="noindex" />
+</head>
+<body>
+
+{{>search/parts/search-header}}
+
+{{>search/parts/search-form}}
+
+<div class="infobox">
+    Showing results containing links between <a href="/site/{{domainA}}">{{domainA}}</a> and <a href="/site/{{domainB}}">{{domainB}}</a>.
+</div>
+{{#each tests}}{{.}}{{/each}}
+<div {{#if hasBoth}}id="crosstalk-view"{{/if}}>
+    <div>
+        {{#each forward}}
+            {{>search/parts/search-result}}
+        {{/each}}
+    </div>
+    <div>
+        {{#each backward}}
+            {{>search/parts/search-result}}
+        {{/each}}
+    </div>
+</div>
+
+
+{{>search/parts/search-footer}}
+</body>
+
+

code/services-application/search-service/src/main/resources/templates/search/site-info/site-info-summary.hdb

@@ -44,7 +44,9 @@
                             {{#if screenshot}}📷{{/if}}
                         </td>
                         <td>
-                            <span title="{{linkType.description}}">{{{linkType}}}</span>
+                            {{#if linkType.isLinked}}
+                                <span title="{{linkType.description}}"><a href="/crosstalk/?domains={{domain}},{{url.domain}}">{{{linkType}}}</a></span>
+                            {{/if}}
                         </td>
                         <td>
                             <span title="{{rank}}%">{{{rankSymbols}}}</span>
@@ -92,7 +94,9 @@
                             {{#if screenshot}}&#x1f4f7;{{/if}}
                         </td>
                         <td>
-                            <span title="{{linkType.description}}">{{{linkType}}}</span>
+                            {{#if linkType.isLinked}}
+                                <span title="{{linkType.description}}"><a href="/crosstalk/?domains={{domain}},{{url.domain}}">{{{linkType}}}</a></span>
+                            {{/if}}
                         </td>
                         <td>
                             <span title="{{rank}}%">{{{rankSymbols}}}</span>