Implement very rough message context for Conpherence search

Summary: Ref T3165. This is pretty awful looking, but should pull the correct data.

Test Plan: {F387567}

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T3165

Differential Revision: https://secure.phabricator.com/D12589

src/__phutil_library_map__.php

@@ -4807,6 +4807,7 @@ phutil_register_library_map(array(
       'PhabricatorPolicyInterface',
       'PhabricatorMarkupInterface',
       'PhabricatorApplicationTransactionInterface',
+      'PhabricatorSubscribableInterface',
     ),
     'PhabricatorCalendarEventDeleteController' => 'PhabricatorCalendarController',
     'PhabricatorCalendarEventEditController' => 'PhabricatorCalendarController',

src/applications/conpherence/query/ConpherenceFulltextQuery.php

@@ -4,6 +4,7 @@ final class ConpherenceFulltextQuery
   extends PhabricatorOffsetPagedQuery {
 
   private $threadPHIDs;
+  private $previousTransactionPHIDs;
   private $fulltext;
 
   public function withThreadPHIDs(array $phids) {
@@ -11,6 +12,11 @@ final class ConpherenceFulltextQuery
     return $this;
   }
 
+  public function withPreviousTransactionPHIDs(array $phids) {
+    $this->previousTransactionPHIDs = $phids;
+    return $this;
+  }
+
   public function withFulltext($fulltext) {
     $this->fulltext = $fulltext;
     return $this;
@@ -42,6 +48,13 @@ final class ConpherenceFulltextQuery
         $this->threadPHIDs);
     }
 
+    if ($this->previousTransactionPHIDs !== null) {
+      $where[] = qsprintf(
+        $conn_r,
+        'i.previousTransactionPHID IN (%Ls)',
+        $this->previousTransactionPHIDs);
+    }
+
     if (strlen($this->fulltext)) {
       $where[] = qsprintf(
         $conn_r,

src/applications/conpherence/query/ConpherenceThreadSearchEngine.php

@@ -149,6 +149,27 @@ final class ConpherenceThreadSearchEngine
       $viewer,
       $conpherences);
 
+    $fulltext = $query->getParameter('fulltext');
+    if (strlen($fulltext) && $conpherences) {
+      $context = $this->loadContextMessages($conpherences, $fulltext);
+
+      $author_phids = array();
+      foreach ($context as $messages) {
+        foreach ($messages as $group) {
+          foreach ($group as $message) {
+            $xaction = $message['xaction'];
+            if ($xaction) {
+              $author_phids[] = $xaction->getAuthorPHID();
+            }
+          }
+        }
+      }
+
+      $handles = $viewer->loadHandles($author_phids);
+    } else {
+      $context = array();
+    }
+
     $list = new PHUIObjectItemListView();
     $list->setUser($viewer);
     foreach ($conpherences as $conpherence) {
@@ -181,6 +202,47 @@ final class ConpherenceThreadSearchEngine
               phabricator_datetime($conpherence->getDateModified(), $viewer)),
           ));
 
+      $messages = idx($context, $conpherence->getPHID());
+      if ($messages) {
+
+        // TODO: This is egregiously under-designed.
+
+        foreach ($messages as $group) {
+          $rows = array();
+          $rowc = array();
+          foreach ($group as $message) {
+            $xaction = $message['xaction'];
+            if (!$xaction) {
+              continue;
+            }
+
+            $rowc[] = ($message['match'] ? 'highlighted' : null);
+            $rows[] = array(
+              $handles->renderHandle($xaction->getAuthorPHID()),
+              $xaction->getComment()->getContent(),
+              phabricator_datetime($xaction->getDateCreated(), $viewer),
+            );
+          }
+          $table = id(new AphrontTableView($rows))
+            ->setHeaders(
+              array(
+                pht('User'),
+                pht('Message'),
+                pht('At'),
+              ))
+            ->setRowClasses($rowc)
+            ->setColumnClasses(
+              array(
+                '',
+                'wide',
+              ));
+          $box = id(new PHUIBoxView())
+            ->appendChild($table)
+            ->addMargin(PHUI::MARGIN_SMALL);
+          $item->appendChild($box);
+        }
+      }
+
       $list->addItem($item);
     }
 
@@ -195,4 +257,209 @@ final class ConpherenceThreadSearchEngine
     );
   }
 
+  private function loadContextMessages(array $threads, $fulltext) {
+    $phids = mpull($threads, 'getPHID');
+
+    // We want to load a few messages for each thread in the result list, to
+    // show some of the actual content hits to help the user find what they
+    // are looking for.
+
+    // This method is trying to batch this lookup in most cases, so we do
+    // between one and "a handful" of queries instead of one per thread in
+    // most cases. To do this:
+    //
+    //   - Load a big block of results for all of the threads.
+    //   - If we didn't get a full block back, we have everything that matches
+    //     the query. Sort it out and exit.
+    //   - Otherwise, some threads had a ton of hits, so we might not be
+    //     getting everything we want (we could be getting back 1,000 hits for
+    //     the first thread). Remove any threads which we have enough results
+    //     for and try again.
+    //   - Repeat until we have everything or every thread has enough results.
+    //
+    // In the worst case, we could end up degrading to one query per thread,
+    // but this is incredibly unlikely on real data.
+
+    // Size of the result blocks we're going to load.
+    $limit = 1000;
+
+    // Number of messages we want for each thread.
+    $want = 3;
+
+    $need = $phids;
+    $hits = array();
+    while ($need) {
+      $rows = id(new ConpherenceFulltextQuery())
+        ->withThreadPHIDs($need)
+        ->withFulltext($fulltext)
+        ->setLimit($limit)
+        ->execute();
+
+      foreach ($rows as $row) {
+        $hits[$row['threadPHID']][] = $row;
+      }
+
+      if (count($rows) < $limit) {
+        break;
+      }
+
+      foreach ($need as $key => $phid) {
+        if (count($hits[$phid]) >= $want) {
+          unset($need[$key]);
+        }
+      }
+    }
+
+    // Now that we have all the fulltext matches, throw away any extras that we
+    // aren't going to render so we don't need to do lookups on them.
+    foreach ($hits as $phid => $rows) {
+      if (count($rows) > $want) {
+        $hits[$phid] = array_slice($rows, 0, $want);
+      }
+    }
+
+    // For each fulltext match, we want to render a message before and after
+    // the match to give it some context. We already know the transactions
+    // before each match because the rows have a "previousTransactionPHID",
+    // but we need to do one more query to figure out the transactions after
+    // each match.
+
+    // Collect the transactions we want to find the next transactions for.
+    $after = array();
+    foreach ($hits as $phid => $rows) {
+      foreach ($rows as $row) {
+        $after[] = $row['transactionPHID'];
+      }
+    }
+
+    // Look up the next transactions.
+    if ($after) {
+      $after_rows = id(new ConpherenceFulltextQuery())
+        ->withPreviousTransactionPHIDs($after)
+        ->execute();
+    } else {
+      $after_rows = array();
+    }
+
+    // Build maps from PHIDs to the previous and next PHIDs.
+    $prev_map = array();
+    $next_map = array();
+    foreach ($after_rows as $row) {
+      $next_map[$row['previousTransactionPHID']] = $row['transactionPHID'];
+    }
+
+    foreach ($hits as $phid => $rows) {
+      foreach ($rows as $row) {
+        $prev = $row['previousTransactionPHID'];
+        if ($prev) {
+          $prev_map[$row['transactionPHID']] = $prev;
+          $next_map[$prev] = $row['transactionPHID'];
+        }
+      }
+    }
+
+    // Now we're going to collect the actual transaction PHIDs, in order, that
+    // we want to show for each thread.
+    $groups = array();
+    foreach ($hits as $thread_phid => $rows) {
+      $rows = ipull($rows, null, 'transactionPHID');
+      foreach ($rows as $phid => $row) {
+        unset($rows[$phid]);
+
+        $group = array();
+
+        // Walk backward, finding all the previous results. We can just keep
+        // going until we run out of results because we've only loaded things
+        // that we want to show.
+        $prev = $phid;
+        while (true) {
+          if (!isset($prev_map[$prev])) {
+            // No previous transaction, so we're done.
+            break;
+          }
+
+          $prev = $prev_map[$prev];
+
+          if (isset($rows[$prev])) {
+            $match = true;
+            unset($rows[$prev]);
+          } else {
+            $match = false;
+          }
+
+          $group[] = array(
+            'phid' => $prev,
+            'match' => $match,
+          );
+        }
+
+        if (count($group) > 1) {
+          $group = array_reverse($group);
+        }
+
+        $group[] = array(
+          'phid' => $phid,
+          'match' => true,
+        );
+
+        $next = $phid;
+        while (true) {
+          if (!isset($next_map[$next])) {
+            break;
+          }
+
+          $next = $next_map[$next];
+
+          if (isset($rows[$next])) {
+            $match = true;
+            unset($rows[$next]);
+          } else {
+            $match = false;
+          }
+
+          $group[] = array(
+            'phid' => $next,
+            'match' => $match,
+          );
+        }
+
+        $groups[$thread_phid][] = $group;
+      }
+    }
+
+    // Load all the actual transactions we need.
+    $xaction_phids = array();
+    foreach ($groups as $thread_phid => $group) {
+      foreach ($group as $list) {
+        foreach ($list as $item) {
+          $xaction_phids[] = $item['phid'];
+        }
+      }
+    }
+
+    if ($xaction_phids) {
+      $xactions = id(new ConpherenceTransactionQuery())
+        ->setViewer($this->requireViewer())
+        ->withPHIDs($xaction_phids)
+        ->needComments(true)
+        ->execute();
+      $xactions = mpull($xactions, null, 'getPHID');
+    } else {
+      $xactions = array();
+    }
+
+    foreach ($groups as $thread_phid => $group) {
+      foreach ($group as $key => $list) {
+        foreach ($list as $lkey => $item) {
+          $xaction = idx($xactions, $item['phid']);
+          $groups[$thread_phid][$key][$lkey]['xaction'] = $xaction;
+        }
+      }
+    }
+
+    // TODO: Sort the groups chronologically?
+
+    return $groups;
+  }
+
 }