Dropdown on commits page to choose branch #1846

I've mostly duplicated the dropdown code from repo/home.tmpl, which
basically only required a change to the URL. This could probably be
broken out into something more modular.

public/js/gogs.js

@@ -218,8 +218,9 @@ function initRepository() {
         });
     }
 
-    // File list
-    if ($('.repository.file.list').length > 0) {
+    // File list and commits
+    if ($('.repository.file.list').length > 0 ||
+         ('.repository.commits').length > 0) {
         initFilterSearchDropdown('.choose.reference .dropdown');
 
         $('.reference.column').click(function () {

templates/repo/commits.tmpl

@@ -2,6 +2,50 @@
 <div class="repository commits">
 	{{template "repo/header" .}}
 	<div class="ui container">
+		<div class="fitted item choose reference">
+			<div class="ui floating filter dropdown" data-no-results="{{.i18n.Tr "repo.pulls.no_results"}}">
+				<div class="ui basic small button">
+					<span class="text">
+						<i class="octicon octicon-git-branch"></i>
+						{{if .IsViewBranch}}{{.i18n.Tr "repo.branch"}}{{else}}{{.i18n.Tr "repo.tree"}}{{end}}:
+						<strong>{{if .IsViewBranch}}{{.BranchName}}{{else}}{{ShortSha .BranchName}}{{end}}</strong>
+					</span>
+					<i class="dropdown icon"></i>
+				</div>
+				<div class="menu">
+					<div class="ui icon search input">
+						<i class="filter icon"></i>
+						<input name="search" placeholder="{{.i18n.Tr "repo.filter_branch_and_tag"}}...">
+					</div>
+					<div class="header">
+						<div class="ui grid">
+							<div class="two column row">
+								<a class="reference column" href="#" data-target="#branch-list">
+									<span class="text {{if .IsViewBranch}}black{{end}}">
+										<i class="icon octicon octicon-git-branch"></i> {{.i18n.Tr "repo.branches"}}
+									</span>
+								</a>
+								<a class="reference column" href="#" data-target="#tag-list">
+									<span class="text {{if .IsViewTag}}black{{end}}">
+										<i class="reference tags icon"></i> {{.i18n.Tr "repo.tags"}}
+									</span>
+								</a>
+							</div>
+						</div>
+					</div>
+					<div id="branch-list" class="scrolling menu" {{if .IsViewTag}}style="display: none"{{end}}>
+						{{range .Branches}}
+							<div class="item {{if eq $.BranchName .}}selected{{end}}" data-url="{{$.RepoLink}}/commits/{{EscapePound .}}">{{.}}</div>
+						{{end}}
+					</div>
+					<div id="tag-list" class="scrolling menu" {{if .IsViewBranch}}style="display: none"{{end}}>
+						{{range .Tags}}
+							<div class="item {{if eq $.BranchName .}}selected{{end}}" data-url="{{$.RepoLink}}/commits/{{EscapePound .}}">{{.}}</div>
+						{{end}}
+					</div>
+				</div>
+			</div>
+		</div>
 		{{template "repo/commits_table" .}}
 	</div>
 </div>