gerrit/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html

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Copyright (C) 2016 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

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distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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limitations under the License.
-->
<link rel="import" href="../../../bower_components/polymer/polymer.html">
<link rel="import" href="../gr-diff-processor/gr-diff-processor.html">

<dom-module id="gr-diff-builder">
  <template>
    <div class="contentWrapper">
      <content></content>
    </div>
    <gr-diff-processor
        id="processor"
        groups="{{_groups}}"></gr-diff-processor>
  </template>
  <script src="../gr-diff/gr-diff-line.js"></script>
  <script src="../gr-diff/gr-diff-group.js"></script>
  <script src="gr-diff-builder.js"></script>
  <script src="gr-diff-builder-side-by-side.js"></script>
  <script src="gr-diff-builder-unified.js"></script>
  <script src="gr-diff-builder-image.js"></script>
  <script>
    (function() {
      'use strict';

      var DiffViewMode = {
        SIDE_BY_SIDE: 'SIDE_BY_SIDE',
        UNIFIED: 'UNIFIED_DIFF',
      };

      Polymer({
        is: 'gr-diff-builder',

        /**
         * Fired when the diff is rendered.
         *
         * @event render
         */

        properties: {
          viewMode: String,
          isImageDiff: Boolean,
          baseImage: Object,
          revisionImage: Object,
          _builder: Object,
          _groups: Array,
        },

        get diffElement() {
          return this.queryEffectiveChildren('#diffTable');
        },

        observers: [
          '_groupsChanged(_groups.splices)',
        ],

        render: function(diff, comments, prefs) {
          // Stop the processor (if it's running).
          this.$.processor.cancel();

          this._builder = this._getDiffBuilder(diff, comments, prefs);

          this.$.processor.context = prefs.context;
          this.$.processor.keyLocations = this._getCommentLocations(comments);

          this._clearDiffContent();

          this.$.processor.process(diff.content).then(function() {
            if (this.isImageDiff) {
              this._builder.renderDiffImages();
            }
            this.fire('render');
          }.bind(this));
        },

        getLineElByChild: function(node) {
          while (node) {
            if (node instanceof Element) {
              if (node.classList.contains('lineNum')) {
                return node;
              }
              if (node.classList.contains('section')) {
                return null;
              }
            }
            node = node.previousSibling || node.parentElement;
          }
          return null;
        },

        renderLineRange: function(startLine, endLine, opt_side) {
          var groups =
              this._builder.getGroupsByLineRange(startLine, endLine, opt_side);
          groups.forEach(function(group) {
            var newElement = this._builder.buildSectionElement(group);
            var oldElement = group.element;

            // Transfer comment threads from existing section to new one.
            var threads = Polymer.dom(newElement).querySelectorAll(
                'gr-diff-comment-thread');
            threads.forEach(function(threadEl) {
              var lineEl = this.getLineElByChild(threadEl, oldElement);
              if (!lineEl) { // New comment thread.
                return;
              }
              var side = this.getSideByLineEl(lineEl);
              var line = lineEl.getAttribute('data-value');
              var oldThreadEl =
                  this.getCommentThreadByLine(line, side, oldElement);
              threadEl.parentNode.replaceChild(oldThreadEl, threadEl);
            }, this);

            // Replace old group elements with new ones.
            group.element.parentNode.replaceChild(newElement, group.element);
            group.element = newElement;
          }, this);

          this.async(function() {
            this.fire('render');
          }, 1);
        },

        getContentByLine: function(lineNumber, opt_side, opt_root) {
          var root = Polymer.dom(opt_root || this.diffElement);
          var sideSelector = !!opt_side ? ('.' + opt_side) : '';
          return root.querySelector('td.lineNum[data-value="' + lineNumber +
              '"]' + sideSelector + ' ~ td.content');
        },

        getContentByLineEl: function(lineEl) {
          var root = Polymer.dom(lineEl.parentElement);
          var side = this.getSideByLineEl(lineEl);
          var line = lineEl.getAttribute('data-value');
          return this.getContentByLine(line, side, root);
        },

        getLineElByNumber: function(lineNumber, opt_side) {
          var sideSelector = !!opt_side ? ('.' + opt_side) : '';
          return this.diffElement.querySelector(
              '.lineNum[data-value="' + lineNumber + '"]' + sideSelector);
        },

        getContentsByLineRange: function(startLine, endLine, opt_side) {
          var groups =
              this._builder.getGroupsByLineRange(startLine, endLine, opt_side);
          // In each group, search Element for lines in range.
          return groups.reduce((function(acc, group) {
            for (var line = startLine; line <= endLine; line++) {
              var content =
                  this.getContentByLine(line, opt_side, group.element);
              if (content) {
                acc.push(content);
              }
            }
            return acc;
          }).bind(this), []);
        },

        getCommentThreadByLine: function(lineNumber, opt_side, opt_root) {
          var root = Polymer.dom(opt_root || this.diffElement);
          var sideSelector = !!opt_side ? ('.' + opt_side) : '';
          var content = this.getContentByLine(lineNumber, opt_side, opt_root);
          return this.getCommentThreadByContentEl(content);
        },

        getCommentThreadByContentEl: function(contentEl) {
          return contentEl.querySelector('gr-diff-comment-thread');
        },

        getSideByLineEl: function(lineEl) {
          return lineEl.classList.contains(GrDiffBuilder.Side.RIGHT) ?
              GrDiffBuilder.Side.RIGHT : GrDiffBuilder.Side.LEFT;
        },

        createCommentThread: function(changeNum, patchNum, path, side,
            projectConfig) {
          return this._builder.createCommentThread(changeNum, patchNum, path,
              side, projectConfig);
        },

        emitGroup: function(group, sectionEl) {
          this._builder.emitGroup(group, sectionEl);
        },

        showContext: function(newGroups, sectionEl) {
          var groups = this._builder.groups;
          // TODO(viktard): Polyfill findIndex for IE10.
          var contextIndex = groups.findIndex(function(group) {
            return group.element == sectionEl;
          });
          groups.splice.apply(groups, [contextIndex, 1].concat(newGroups));

          newGroups.forEach(function(newGroup) {
            this._builder.emitGroup(newGroup, sectionEl);
          }, this);
          sectionEl.parentNode.removeChild(sectionEl);

          this.async(function() {
            this.fire('render');
          }, 1);
        },

        _getDiffBuilder: function(diff, comments, prefs) {
          if (this.isImageDiff) {
            return new GrDiffBuilderImage(diff, comments, prefs,
                this.diffElement, this.baseImage, this.revisionImage);
          } else if (this.viewMode === DiffViewMode.SIDE_BY_SIDE) {
            return new GrDiffBuilderSideBySide(
                diff, comments, prefs, this.diffElement);
          } else if (this.viewMode === DiffViewMode.UNIFIED) {
            return new GrDiffBuilderUnified(
                diff, comments, prefs, this.diffElement);
          }
          throw Error('Unsupported diff view mode: ' + this.viewMode);
        },

        _clearDiffContent: function() {
          this.diffElement.innerHTML = null;
        },

        _getCommentLocations: function(comments) {
          var result = {
            left: {},
            right: {},
          };
          for (var side in comments) {
            if (side !== GrDiffBuilder.Side.LEFT &&
                side !== GrDiffBuilder.Side.RIGHT) {
              continue;
            }
            comments[side].forEach(function(c) {
              result[side][c.line || GrDiffLine.FILE] = true;
            });
          }
          return result;
        },

        _groupsChanged: function(changeRecord) {
          if (!changeRecord) { return; }
          changeRecord.indexSplices.forEach(function(splice) {
            var group;
            for (var i = 0; i < splice.addedCount; i++) {
              group = splice.object[splice.index + i];
              this._builder.groups.push(group);
              this._builder.emitGroup(group);
            }
          }, this);
        },
      });
    })();
  </script>
</dom-module>