#!/bin/bash

set -eu

# Only execute in the verify pipeline
[[ "$BUILDKITE_PIPELINE_NAME" =~ verify$ ]] || exit 0

docker ps || true
free -m || true

# We've now seen cases where origin/master on the build hosts can get
# out of date. This causes us to build components unnecessarily.
# Fetching it here hopefully will prevent this situation.
echo "Fetching origin/master"
git fetch origin master

# DEBUGGING FOR RELENG
# Fetch the git tags to see if that addresses the weird smart build behavior for Habitat
git fetch --tags --force

# Rebase onto current master to ensure this PR is closer to what happens when it's merged.
# Only do this if it's actually a branch (i.e. a PR or a manually created build), not a
# post-merge CI run of master.
if [[ "$BUILDKITE_BRANCH" != "master" ]]; then
  git config user.email "you@example.com" # these are needed for the rebase attempt
  git config user.name "Your Name"
  master=$(git show-ref -s --abbrev origin/master)
  pr_head=$(git show-ref -s --abbrev HEAD)
  github="https://github.com/chef/chef/commit/"
  if git rebase origin/master >/dev/null; then
    buildkite-agent annotate --style success --context "rebase-pr-branch-${master}" \
      "Rebased onto master ([${master}](${github}${master}))."
  else
    git rebase --abort
    buildkite-agent annotate --style warning --context "rebase-pr-branch-${master}" \
      "Couldn't rebase onto master ([${master}](${github}${master})), building PR HEAD ([${pr_head}](${github}${pr_head}))."
  fi
fi