Allow moving wiki pages from the UI

7 files changed, 94 insertions, 19 deletions

diff --git a/app/assets/stylesheets/pages/wiki.scss b/app/assets/stylesheets/pages/wiki.scss
index d8fec583121..e70a57c2a67 100644
--- a/app/assets/stylesheets/pages/wiki.scss
+++ b/app/assets/stylesheets/pages/wiki.scss
@@ -6,6 +6,14 @@
   }
 }
 
+.wiki-form {
+  .edit-wiki-page-slug-tip {
+    display: inline-block;
+    max-width: 100%;
+    margin-top: 5px;
+  }
+}
+
 .title .edit-wiki-header {
   width: 780px;
   margin-left: auto;
diff --git a/app/controllers/projects/wikis_controller.rb b/app/controllers/projects/wikis_controller.rb
index 292e4158f8b..fde96cbd35d 100644
--- a/app/controllers/projects/wikis_controller.rb
+++ b/app/controllers/projects/wikis_controller.rb
@@ -54,8 +54,8 @@ class Projects::WikisController < Projects::ApplicationController
     else
       render 'edit'
     end
-  rescue WikiPage::PageChangedError
-    @conflict = true
+  rescue WikiPage::PageChangedError, WikiPage::PageRenameError => e
+    @error = e
     render 'edit'
   end
 
diff --git a/app/helpers/wiki_helper.rb b/app/helpers/wiki_helper.rb
index 815fab9e061..41f9eedd4bd 100644
--- a/app/helpers/wiki_helper.rb
+++ b/app/helpers/wiki_helper.rb
@@ -21,4 +21,22 @@ module WikiHelper
         add_to_breadcrumb_dropdown link_to(WikiPage.unhyphenize(dir_or_page).capitalize, project_wiki_path(@project, current_slug)), location: :after
       end
   end
+
+  def wiki_page_errors(error)
+    return unless error
+
+    content_tag(:div, class: 'alert alert-danger') do
+      case error
+      when WikiPage::PageChangedError
+        page_link = link_to s_("WikiPageConflictMessage|the page"), project_wiki_path(@project, @page), target: "_blank"
+        concat(
+          (s_("WikiPageConflictMessage|Someone edited the page the same time you did. Please check out %{page_link} and make sure your changes will not unintentionally remove theirs.") % { page_link: page_link }).html_safe
+        )
+      when WikiPage::PageRenameError
+        s_("WikiEdit|There is already a page with the same title in that path.")
+      else
+        error.message
+      end
+    end
+  end
 end
diff --git a/app/models/project_wiki.rb b/app/models/project_wiki.rb
index 459d1673125..f6041da986c 100644
--- a/app/models/project_wiki.rb
+++ b/app/models/project_wiki.rb
@@ -119,6 +119,8 @@ class ProjectWiki
   end
 
   def delete_page(page, message = nil)
+    return unless page
+
     wiki.delete_page(page.path, commit_details(:deleted, message, page.title))
 
     update_project_activity
@@ -131,6 +133,8 @@ class ProjectWiki
   end
 
   def page_title_and_dir(title)
+    return unless title
+
     title_array = title.split("/")
     title = title_array.pop
     [title, title_array.join("/")]
diff --git a/app/models/wiki_page.rb b/app/models/wiki_page.rb
index e6254183baf..0f5536415f7 100644
--- a/app/models/wiki_page.rb
+++ b/app/models/wiki_page.rb
@@ -1,5 +1,6 @@
 class WikiPage
   PageChangedError = Class.new(StandardError)
+  PageRenameError = Class.new(StandardError)
 
   include ActiveModel::Validations
   include ActiveModel::Conversion
@@ -102,7 +103,7 @@ class WikiPage
 
   # The hierarchy of the directory this page is contained in.
   def directory
-    wiki.page_title_and_dir(slug).last
+    wiki.page_title_and_dir(slug)&.last.to_s
   end
 
   # The processed/formatted content of this page.
@@ -177,7 +178,7 @@ class WikiPage
   # Creates a new Wiki Page.
   #
   # attr - Hash of attributes to set on the new page.
-  #       :title   - The title for the new page.
+  #       :title   - The title (optionally including dir) for the new page.
   #       :content - The raw markup content.
   #       :format  - Optional symbol representing the
   #                  content format. Can be any type
@@ -189,7 +190,7 @@ class WikiPage
   # Returns the String SHA1 of the newly created page
   # or False if the save was unsuccessful.
   def create(attrs = {})
-    @attributes.merge!(attrs)
+    update_attributes(attrs)
 
     save(page_details: title) do
       wiki.create_page(title, content, format, message)
@@ -204,24 +205,29 @@ class WikiPage
   #                           See ProjectWiki::MARKUPS Hash for available formats.
   #        :message         - Optional commit message to set on the new version.
   #        :last_commit_sha - Optional last commit sha to validate the page unchanged.
-  #        :title           - The Title to replace existing title
+  #        :title           - The Title (optionally including dir) to replace existing title
   #
   # Returns the String SHA1 of the newly created page
   # or False if the save was unsuccessful.
   def update(attrs = {})
     last_commit_sha = attrs.delete(:last_commit_sha)
+
     if last_commit_sha && last_commit_sha != self.last_commit_sha
-      raise PageChangedError.new("You are attempting to update a page that has changed since you started editing it.")
+      raise PageChangedError
     end
 
-    attrs.slice!(:content, :format, :message, :title)
-    @attributes.merge!(attrs)
-    page_details =
-      if title.present? && @page.title != title
-        title
-      else
-        @page.url_path
+    update_attributes(attrs)
+
+    if title_changed?
+      page_details = title
+
+      if wiki.find_page(page_details).present?
+        @attributes[:title] = @page.url_path
+        raise PageRenameError
       end
+    else
+      page_details = @page.url_path
+    end
 
     save(page_details: page_details) do
       wiki.update_page(
@@ -255,8 +261,44 @@ class WikiPage
     page.version.to_s
   end
 
+  def title_changed?
+    title.present? && self.class.unhyphenize(@page.url_path) != title
+  end
+
   private
 
+  # Process and format the title based on the user input.
+  def process_title(title)
+    return if title.blank?
+
+    title = deep_title_squish(title)
+    current_dirname = File.dirname(title)
+
+    if @page.present?
+      return title[1..-1] if current_dirname == '/'
+      return File.join([directory.presence, title].compact) if current_dirname == '.'
+    end
+
+    title
+  end
+
+  # This method squishes all the filename
+  # i.e: '   foo   /  bar  / page_name' => 'foo/bar/page_name'
+  def deep_title_squish(title)
+    components = title.split(File::SEPARATOR).map(&:squish)
+
+    File.join(components)
+  end
+
+  # Updates the current @attributes hash by merging a hash of params
+  def update_attributes(attrs)
+    attrs[:title] = process_title(attrs[:title]) if attrs[:title].present?
+
+    attrs.slice!(:content, :format, :message, :title)
+
+    @attributes.merge!(attrs)
+  end
+
   def set_attributes
     attributes[:slug] = @page.url_path
     attributes[:title] = @page.title
diff --git a/app/views/projects/wikis/_form.html.haml b/app/views/projects/wikis/_form.html.haml
index 4e265bf733a..d285251d06f 100644
--- a/app/views/projects/wikis/_form.html.haml
+++ b/app/views/projects/wikis/_form.html.haml
@@ -9,7 +9,13 @@
 
   .form-group
     .col-sm-12= f.label :title, class: 'control-label-full-width'
-    .col-sm-12= f.text_field :title, class: 'form-control', value: @page.title
+    .col-sm-12
+      = f.text_field :title, class: 'form-control', value: @page.title
+      - if @page.persisted?
+        %span.edit-wiki-page-slug-tip
+          = icon('lightbulb-o')
+          = s_("WikiEditPageTip|Tip: You can move this page by adding the path to the beginning of the title.")
+          = link_to icon('question-circle'), help_page_path('user/project/wiki/index', anchor: 'moving-a-wiki-page'), target: '_blank'
   .form-group
     .col-sm-12= f.label :format, class: 'control-label-full-width'
     .col-sm-12
diff --git a/app/views/projects/wikis/edit.html.haml b/app/views/projects/wikis/edit.html.haml
index 0d77e5bd16d..9d3d4072027 100644
--- a/app/views/projects/wikis/edit.html.haml
+++ b/app/views/projects/wikis/edit.html.haml
@@ -1,10 +1,7 @@
 - @content_class = "limit-container-width limit-container-width-sm" unless fluid_layout
 - page_title _("Edit"), @page.title.capitalize, _("Wiki")
 
-- if @conflict
-  .alert.alert-danger
-    - page_link = link_to s_("WikiPageConflictMessage|the page"), project_wiki_path(@project, @page), target: "_blank"
-    = (s_("WikiPageConflictMessage|Someone edited the page the same time you did. Please check out %{page_link} and make sure your changes will not unintentionally remove theirs.") % { page_link: page_link }).html_safe
+= wiki_page_errors(@error)
 
 .wiki-page-header.has-sidebar-toggle
   %button.btn.btn-default.sidebar-toggle.js-sidebar-wiki-toggle{ role: "button", type: "button" }