require 'spec_helper'

feature 'Expand and collapse diffs', js: true, feature: true do
  let(:branch) { 'expand-collapse-diffs' }
  let(:project) { create(:project, :repository) }

  before do
    # Set the limits to those when these specs were written, to avoid having to
    # update the test repo every time we change them.
    allow(Gitlab::Git::Diff).to receive(:size_limit).and_return(100.kilobytes)
    allow(Gitlab::Git::Diff).to receive(:collapse_limit).and_return(10.kilobytes)

    login_as :admin

    # Ensure that undiffable.md is in .gitattributes
    project.repository.copy_gitattributes(branch)
    visit namespace_project_commit_path(project.namespace, project, project.commit(branch))
    execute_script('window.ajaxUris = []; $(document).ajaxSend(function(event, xhr, settings) { ajaxUris.push(settings.url) });')
  end

  def file_container(filename)
    find("[data-blob-diff-path*='#{filename}']")
  end

  # Use define_method instead of let (which is memoized) so that this just works across a
  # reload.
  #
  files = [
    'small_diff.md', 'large_diff.md', 'large_diff_renamed.md', 'undiffable.md',
    'too_large.md', 'too_large_image.jpg'
  ]

  files.each do |file|
    define_method(file.split('.').first) { file_container(file) }
  end

  it 'should show the diff content with a highlighted line when linking to line' do
    expect(large_diff).not_to have_selector('.code')
    expect(large_diff).to have_selector('.nothing-here-block')

    visit namespace_project_commit_path(project.namespace, project, project.commit(branch), anchor: "#{large_diff[:id]}_0_1")
    execute_script('window.location.reload()')

    wait_for_requests

    expect(large_diff).to have_selector('.code')
    expect(large_diff).not_to have_selector('.nothing-here-block')
    expect(large_diff).to have_selector('.hll')
  end

  it 'should show the diff content when linking to file' do
    expect(large_diff).not_to have_selector('.code')
    expect(large_diff).to have_selector('.nothing-here-block')

    visit namespace_project_commit_path(project.namespace, project, project.commit(branch), anchor: large_diff[:id])
    execute_script('window.location.reload()')

    wait_for_requests

    expect(large_diff).to have_selector('.code')
    expect(large_diff).not_to have_selector('.nothing-here-block')
  end

  context 'visiting a commit with collapsed diffs' do
    it 'shows small diffs immediately' do
      expect(small_diff).to have_selector('.code')
      expect(small_diff).not_to have_selector('.nothing-here-block')
    end

    it 'shows non-renderable diffs as such immediately, regardless of their size' do
      expect(undiffable).not_to have_selector('.code')
      expect(undiffable).to have_selector('.nothing-here-block')
      expect(undiffable).to have_content('gitattributes')
    end

    it 'does not allow diffs that are larger than the maximum size to be expanded' do
      expect(too_large).not_to have_selector('.code')
      expect(too_large).to have_selector('.nothing-here-block')
      expect(too_large).to have_content('too large')
    end

    it 'shows image diffs immediately, regardless of their size' do
      expect(too_large_image).not_to have_selector('.nothing-here-block')
      expect(too_large_image).to have_selector('.image')
    end

    context 'expanding a diff for a renamed file' do
      before do
        large_diff_renamed.find('.click-to-expand').click
        wait_for_requests
      end

      it 'shows the old content' do
        old_line = large_diff_renamed.find('.line_content.old')

        expect(old_line).to have_content('two copies')
      end

      it 'shows the new content' do
        new_line = large_diff_renamed.find('.line_content.new', match: :prefer_exact)

        expect(new_line).to have_content('three copies')
      end
    end

    context 'expanding a large diff' do
      before do
        # Wait for diffs
        find('.js-file-title', match: :first)
        # Click `large_diff.md` title
        all('.diff-toggle-caret')[1].click
        wait_for_requests
      end

      it 'makes a request to get the content' do
        ajax_uris = evaluate_script('ajaxUris')

        expect(ajax_uris).not_to be_empty
        expect(ajax_uris.first).to include('large_diff.md')
      end

      it 'shows the diff content' do
        expect(large_diff).to have_selector('.code')
        expect(large_diff).not_to have_selector('.nothing-here-block')
      end

      context 'adding a comment to the expanded diff' do
        let(:comment_text) { 'A comment' }

        before do
          large_diff.find('.diff-line-num', match: :prefer_exact).hover
          large_diff.find('.add-diff-note').click
          large_diff.find('.note-textarea').send_keys comment_text
          large_diff.find_button('Comment').click
          wait_for_requests
        end

        it 'adds the comment' do
          expect(large_diff.find('.notes')).to have_content comment_text
        end

        context 'reloading the page' do
          before do
            refresh
          end

          it 'collapses the large diff by default' do
            expect(large_diff).not_to have_selector('.code')
            expect(large_diff).to have_selector('.nothing-here-block')
          end

          context 'expanding the diff' do
            before do
              # Wait for diffs
              find('.js-file-title', match: :first)
              # Click `large_diff.md` title
              all('.diff-toggle-caret')[1].click
              wait_for_requests
            end

            it 'shows the diff content' do
              expect(large_diff).to have_selector('.code')
              expect(large_diff).not_to have_selector('.nothing-here-block')
            end

            it 'shows the diff comment' do
              expect(large_diff.find('.notes')).to have_content comment_text
            end
          end
        end
      end
    end

    context 'collapsing an expanded diff' do
      before do
        # Wait for diffs
        find('.js-file-title', match: :first)
        # Click `small_diff.md` title
        all('.diff-toggle-caret')[3].click
      end

      it 'hides the diff content' do
        expect(small_diff).not_to have_selector('.code')
        expect(small_diff).to have_selector('.nothing-here-block')
      end

      context 're-expanding the same diff' do
        before do
          # Wait for diffs
          find('.js-file-title', match: :first)
          # Click `small_diff.md` title
          all('.diff-toggle-caret')[3].click
        end

        it 'shows the diff content' do
          expect(small_diff).to have_selector('.code')
          expect(small_diff).not_to have_selector('.nothing-here-block')
        end

        it 'does not make a new HTTP request' do
          expect(evaluate_script('ajaxUris')).not_to include(a_string_matching('small_diff.md'))
        end
      end
    end

    context 'expanding a diff when symlink was converted to a regular file' do
      let(:branch) { 'symlink-expand-diff' }

      it 'shows the content of the regular file' do
        expect(page).to have_content('This diff is collapsed')
        expect(page).to have_no_content('No longer a symlink')

        find('.click-to-expand').click
        wait_for_requests

        expect(page).to have_content('No longer a symlink')
      end
    end
  end

  context 'visiting a commit without collapsed diffs' do
    let(:branch) { 'feature' }

    it 'does not show Expand all button' do
      expect(page).not_to have_link('Expand all')
    end
  end

  context 'visiting a commit with more than safe files' do
    let(:branch) { 'expand-collapse-files' }

    # safe-files -> 100 | safe-lines -> 5000 | commit-files -> 105
    it 'does collapsing from the safe number of files to the end on small files' do
      expect(page).to have_link('Expand all')

      expect(page).to have_selector('.diff-content', count: 105)
      expect(page).to have_selector('.diff-collapsed', count: 5)

      %w(file-95.txt file-96.txt file-97.txt file-98.txt file-99.txt).each do |filename|
        expect(find("[data-blob-diff-path*='#{filename}']")).to have_selector('.diff-collapsed')
      end
    end
  end

  context 'visiting a commit with more than safe lines' do
    let(:branch) { 'expand-collapse-lines' }

    # safe-files -> 100 | safe-lines -> 5000 | commit_files -> 8 (each 1250 lines)
    it 'does collapsing from the safe number of lines to the end' do
      expect(page).to have_link('Expand all')

      expect(page).to have_selector('.diff-content', count: 6)
      expect(page).to have_selector('.diff-collapsed', count: 2)

      %w(file-4.txt file-5.txt).each do |filename|
        expect(find("[data-blob-diff-path*='#{filename}']")).to have_selector('.diff-collapsed')
      end
    end
  end

  context 'expanding all diffs' do
    before do
      click_link('Expand all')

      # Wait for elements to appear to ensure full page reload
      expect(page).to have_content('This diff was suppressed by a .gitattributes entry')
      expect(page).to have_content('This source diff could not be displayed because it is too large.')
      expect(page).to have_content('too_large_image.jpg')
      find('.note-textarea')

      wait_for_requests
      execute_script('window.ajaxUris = []; $(document).ajaxSend(function(event, xhr, settings) { ajaxUris.push(settings.url) });')
    end

    it 'reloads the page with all diffs expanded' do
      expect(small_diff).to have_selector('.code')
      expect(small_diff).not_to have_selector('.nothing-here-block')

      expect(large_diff).to have_selector('.code')
      expect(large_diff).not_to have_selector('.nothing-here-block')
    end

    context 'collapsing an expanded diff' do
      before do
        # Wait for diffs
        find('.js-file-title', match: :first)
        # Click `small_diff.md` title
        all('.diff-toggle-caret')[3].click
      end

      it 'hides the diff content' do
        expect(small_diff).not_to have_selector('.code')
        expect(small_diff).to have_selector('.nothing-here-block')
      end

      context 're-expanding the same diff' do
        before do
          # Wait for diffs
          find('.js-file-title', match: :first)
          # Click `small_diff.md` title
          all('.diff-toggle-caret')[3].click
        end

        it 'shows the diff content' do
          expect(small_diff).to have_selector('.code')
          expect(small_diff).not_to have_selector('.nothing-here-block')
        end

        it 'does not make a new HTTP request' do
          expect(evaluate_script('ajaxUris')).not_to include(a_string_matching('small_diff.md'))
        end
      end
    end
  end
end