// Munge is the workhorse the will actually make updates to the PR
func (c *ClearPickAfterMerge) Munge(obj *github.MungeObject) {
	if !obj.IsPR() {
		return
	}
	if !obj.HasLabel(cpCandidateLabel) {
		return
	}

	if merged, err := obj.IsMerged(); !merged || err != nil {
		return
	}

	releaseMilestone := obj.ReleaseMilestone()
	if releaseMilestone == "" || len(releaseMilestone) != 4 {
		glog.Errorf("Found invalid milestone: %q", releaseMilestone)
		return
	}
	rel := releaseMilestone[1:]
	branch := "release-" + rel

	sha := obj.MergeCommit()
	if sha == nil {
		glog.Errorf("Unable to get SHA of merged %d", sha)
		return
	}

	logMsg := fmt.Sprintf("Merge pull request #%d from ", *obj.Issue.Number)
	bLogMsg := []byte(logMsg)

	cherrypickMsg := fmt.Sprintf("(cherry picked from commit %s)", *sha)
	args := []string{"log", "--pretty=tformat:%H%n%s%n%b", "--grep", cherrypickMsg, "origin/" + branch}
	out, err := c.features.Repos.GitCommand(args)
	if err != nil {
		glog.Errorf("Error grepping for cherrypick -x message out=%q: %v", string(out), err)
		return
	}
	if bytes.Contains(out, bLogMsg) {
		glog.Infof("Found cherry-pick using -x information")
		handleFound(obj, out, branch)
		return
	}

	args = []string{"log", "--pretty=tformat:%H%n%s%n%b", "--grep", logMsg, "origin/" + branch}
	out, err = c.features.Repos.GitCommand(args)
	if err != nil {
		glog.Errorf("Error grepping for log message out=%q: %v", string(out), err)
		return
	}
	if bytes.Contains(out, bLogMsg) {
		glog.Infof("Found cherry-pick using log matching")
		handleFound(obj, out, branch)
		return
	}

	return
}
// Can we find a commit in the changelog that looks like it was done using git cherry-pick -m1 -x ?
func (c *ClearPickAfterMerge) foundByPickDashX(obj *github.MungeObject, branch string) bool {
	sha := obj.MergeCommit()
	if sha == nil {
		glog.Errorf("Unable to get SHA of merged PR %d", *obj.Issue.Number)
		return false
	}

	cherrypickMsg := fmt.Sprintf("(cherry picked from commit %s)", *sha)
	found, logs := c.foundLog(branch, cherrypickMsg)
	if !found {
		return false
	}

	// double check for the 'non -x' message
	logMsg := fmt.Sprintf("Merge pull request #%d from ", *obj.Issue.Number)
	if !strings.Contains(logs, logMsg) {
		return false
	}
	glog.Infof("Found cherry-pick for %d using -x information in branch %q", *obj.Issue.Number, branch)
	return true
}