#!/usr/bin/env bash

# Usage: git-push-all.sh -t <test-branch-prefix> -r <remote-name> <git-opts>
#        env vars: TOR_UPSTREAM_REMOTE_NAME=upstream TOR_PUSH_DELAY=0
#        git-opts: --no-atomic --dry-run (any other git push option)
#
# TOR_PUSH_DELAY pushes the master and maint branches separately, so that CI
# runs in a sensible order.
# push --atomic is the default when TOR_PUSH_DELAY=0, and for release branches.

set -e

#################
# Configuration #
#################

# Don't change this configuration - set the env vars in your .profile
#
# The upstream remote which git.torproject.org/tor.git points to.
# In test branch mode, override this setting with -r <remote-name>
UPSTREAM_REMOTE=${TOR_UPSTREAM_REMOTE_NAME:-"upstream"}
# Add a delay between pushes, so CI runs on the most important branches first
PUSH_DELAY=${TOR_PUSH_DELAY:-0}

#######################
# Argument processing #
#######################

# Controlled by the -t <test-branch-prefix> option. The test branch base
# name option makes git-merge-forward.sh create new test branches:
# <tbbn>_029, <tbbn>_035, ... , <tbbn>_master, and merge forward.
TEST_BRANCH_PREFIX=

while getopts ":r:t:" opt; do
  case "$opt" in
    r) UPSTREAM_REMOTE="$OPTARG"
       echo "    *** PUSHING TO REMOTE: ${UPSTREAM_REMOTE} ***"
       shift
       shift
       OPTIND=$[$OPTIND - 2]
       ;;
    t) TEST_BRANCH_PREFIX="$OPTARG"
       echo "    *** PUSHING TEST BRANCHES: ${TEST_BRANCH_PREFIX}_nnn ***"
       shift
       shift
       OPTIND=$[$OPTIND - 2]
       ;;
    *)
       # Assume git push will handle the option
       ;;
  esac
done

if [ "$TEST_BRANCH_PREFIX" ]; then
  if [ "$UPSTREAM_REMOTE" = ${TOR_UPSTREAM_REMOTE_NAME:-"upstream"} ]; then
    echo "Pushing test branches ${TEST_BRANCH_PREFIX}_nnn to " \
      "$UPSTREAM_REMOTE is not allowed."
    echo "Usage: $0 -r <remote-name> -t <test-branch-prefix> <git-opts>"
    exit 1
  fi
fi

########################
# Git branches to push #
########################

PUSH_BRANCHES=$(echo \
  master \
  {release,maint}-0.4.1 \
  {release,maint}-0.4.0 \
  {release,maint}-0.3.5 \
  {release,maint}-0.2.9 \
  )

if [ -z "$TEST_BRANCH_PREFIX" ]; then

  # maint/release push mode
  #
  # List of branches to push. Ordering is not important.
  PUSH_BRANCHES=$(echo \
    master \
    {release,maint}-0.4.1 \
    {release,maint}-0.4.0 \
    {release,maint}-0.3.5 \
    {release,maint}-0.2.9 \
    )
else

  # Test branch mode: merge to maint only, and create a new branch for 0.2.9
  #
  # List of branches to push. Ordering is not important.
  PUSH_BRANCHES=$(echo \
    ${TEST_BRANCH_PREFIX}_master \
    ${TEST_BRANCH_PREFIX}_041 \
    ${TEST_BRANCH_PREFIX}_040 \
    ${TEST_BRANCH_PREFIX}_035 \
    ${TEST_BRANCH_PREFIX}_029 \
    )
fi

###############
# Entry point #
###############

if [ "$PUSH_DELAY" -le 0 ]; then
  echo "Pushing $PUSH_BRANCHES"
  # We know that there are no spaces in any branch within $PUSH_BRANCHES, so
  # it is safe to use it unquoted.  (This also applies to the other shellcheck
  # exceptions below.)
  #
  # shellcheck disable=SC2086
  git push --atomic "$@" "$UPSTREAM_REMOTE" $PUSH_BRANCHES
else
  PUSH_BRANCHES=$(echo "$PUSH_BRANCHES" | tr " " "\n" | sort -V)
  MASTER_BRANCH=$(echo "$PUSH_BRANCHES" | tr " " "\n" | grep master)
  if [ -z "$TEST_BRANCH_PREFIX" ]; then
    MAINT_BRANCHES=$(echo "$PUSH_BRANCHES" | tr " " "\n" | grep maint)
    RELEASE_BRANCHES=$(echo "$PUSH_BRANCHES" | tr " " "\n" | grep release | \
      tr "\n" " ")
    printf "Pushing with %ss delays, so CI runs in this order:\n%s\n%s\n%s\n" \
      "$PUSH_DELAY" "$MASTER_BRANCH" "$MAINT_BRANCHES" "$RELEASE_BRANCHES"
  else
    # Actually test branches based on maint branches
    MAINT_BRANCHES=$(echo "$PUSH_BRANCHES" | tr " " "\n" | grep -v master)
    printf "Pushing with %ss delays, so CI runs in this order:\n%s\n%s\n" \
      "$PUSH_DELAY" "$MASTER_BRANCH" "$MAINT_BRANCHES"
    # No release branches
    RELEASE_BRANCHES=
  fi
  git push "$@" "$UPSTREAM_REMOTE" "$MASTER_BRANCH"
  sleep "$PUSH_DELAY"
  # shellcheck disable=SC2086
  for b in $MAINT_BRANCHES; do
    git push "$@" "$UPSTREAM_REMOTE" "$b"
    sleep "$PUSH_DELAY"
  done
  if [ "$RELEASE_BRANCHES" ]; then
    # shellcheck disable=SC2086
    git push --atomic "$@" "$UPSTREAM_REMOTE" $RELEASE_BRANCHES
  fi
fi