Add support for link group and its sort

src/main/java/run/halo/app/controller/admin/api/LinkController.java

@@ -5,6 +5,8 @@
 
 import io.swagger.annotations.ApiOperation;
 import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
 import javax.validation.Valid;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.web.SortDefault;
@@ -17,6 +19,7 @@
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import run.halo.app.model.dto.LinkDTO;
+import run.halo.app.model.dto.base.InputConverter;
 import run.halo.app.model.entity.Link;
 import run.halo.app.model.params.LinkParam;
 import run.halo.app.service.LinkService;
@@ -75,4 +78,26 @@ public void deletePermanently(@PathVariable("id") Integer id) {
     public List<String> teams() {
         return linkService.listAllTeams();
     }
+
+    /**
+     * Update the links in batch.
+     *
+     * <p>To realize the draggable sort approach for link priority,
+     * a links batch update API is in demand.
+     *
+     * @param linkParams the modified links params.
+     * @return the links after updated.
+     */
+    @PutMapping("/batch")
+    @ApiOperation("Updates links in batch")
+    public List<LinkDTO> updateBatchBy(@RequestBody List<@Valid LinkParam> linkParams) {
+        List<Link> links = linkParams
+            .stream()
+            .filter(linkParam -> Objects.nonNull(linkParam.getId()))
+            .map(InputConverter::convertTo)
+            .collect(Collectors.toList());
+        return linkService.updateInBatch(links).stream()
+            .map(link -> (LinkDTO) new LinkDTO().convertFrom(link))
+            .collect(Collectors.toList());
+    }
 }

src/main/java/run/halo/app/model/params/LinkParam.java

@@ -17,6 +17,8 @@
 @Data
 public class LinkParam implements InputConverter<Link> {
 
+    private Integer id;
+
     @NotBlank(message = "友情链接名称不能为空")
     @Size(max = 255, message = "友情链接名称的字符长度不能超过 {max}")
     private String name;

src/main/java/run/halo/app/repository/LinkRepository.java

@@ -17,7 +17,7 @@ public interface LinkRepository extends BaseRepository<Link, Integer> {
      *
      * @return a list of teams
      */
-    @Query(value = "select distinct a.team from Link a")
+    @Query(value = "select a.team from Link a group by a.team order by max(a.priority) DESC")
     List<String> findAllTeams();
 
     boolean existsByNameAndIdNot(String name, Integer id);

src/main/java/run/halo/app/service/impl/LinkServiceImpl.java

@@ -1,6 +1,7 @@
 package run.halo.app.service.impl;
 
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -61,21 +62,38 @@ public LinkServiceImpl(LinkRepository linkRepository) {
             ServiceUtils.convertToListMap(teams, links, LinkDTO::getTeam);
 
         List<LinkTeamVO> result = new LinkedList<>();
-
+        Map<LinkTeamVO, Integer> teamPriorities = new HashMap<>();
         // Wrap link team vo list
         teamLinkListMap.forEach((team, linkList) -> {
             // Build link team vo
             LinkTeamVO linkTeamVO = new LinkTeamVO();
             linkTeamVO.setTeam(team);
             linkTeamVO.setLinks(linkList);
 
+            teamPriorities.put(linkTeamVO, getTeamPriority(linkTeamVO));
             // Add it to result
             result.add(linkTeamVO);
         });
 
+        result.sort((a, b) -> teamPriorities.get(b) - teamPriorities.get(a));
+
         return result;
     }
 
+
+    /**
+     * Get the priority of a link team, which is the maximum priority of its link members.
+     *
+     * @param linkTeam A team of links.
+     * @return the priority of a link team.
+     */
+    private Integer getTeamPriority(LinkTeamVO linkTeam) {
+        return linkTeam.getLinks().stream()
+            .mapToInt(LinkDTO::getPriority)
+            .max()
+            .orElse(-1);
+    }
+
     @Override
     public @NonNull List<LinkTeamVO> listTeamVosByRandom(@NonNull Sort sort) {
         Assert.notNull(sort, "Sort info must not be null");