/*
* Copyright 2000-2014 JetBrains s.r.o.
*
* 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.intellij.vcs.log.graph;
import com.intellij.vcs.log.VcsLogRefManager;
public interface GraphColorManager<CommitId> {
/**
* Returns the color which should be used to draw the given branch.
*
* @param headCommit branch head commit index.
*/
int getColorOfBranch(CommitId headCommit);
/**
* Returns the color which should be used to draw a not-main fragment of a branch
* (e.g. there was master, then I've checked out a feature, made some commits and merged back to master - these my commits form such
* a fragment which is the same branch in terms of VCS, but is a separate branch in terms of graph,
* and therefore we may want to color it separately.
*
* @param headCommit commit of the branch head which the fragment belongs to.
* @param magicIndex some magic index identifying the fragment (we don't know which one - it is some Graph internal thing).
* @return the colorId which should be used to draw this fragment.
*/
int getColorOfFragment(CommitId headCommit, int magicIndex);
/**
* Compares two head commits, which represent graph branches, by expected positions of these branches in the graph,
* and thus by their "importance".
* <p/>
* If branch1 is more important than branch2, branch1 will be laid out more to the left from the branch2, and
* the color of branch1 will be reused by the subgraph below the point when these branches have diverged.
* <p/>
* <ul>
* <li><b>Negative</b> value is returned if the branch represented by {@code head1} should be laid out at the left,
* i.e. if {@code head1} is more important than {@code head2}.
* <li><b>Positive</b> value is returned if the branch represented by {@code head1} should be laid out at the right from {@code head2}.
* i.e. if {@code head1} is less important than {@code head2}.
* <li>Zero is returned if the given commits are equal.
* </ul>
*
* @see VcsLogRefManager#getBranchLayoutComparator()
*/
int compareHeads(CommitId head1, CommitId head2);
}