#!/usr/bin/env bash

# TODO:
#
# - Check if the branch already exists in the remote => checkout
# - Better error handling
# - Just checkout, don't build
# - Rebase functionality
#

set -x
set -e
set -o pipefail

# setup_contrib_git("_build_ci/fiat", "https://github.com/ejgallego/fiat-core.git")
setup_contrib_git() {

    local _DIR=$1
    local _GITURL=$2

    ( cd $_DIR
      git checkout -b $OVERLAY_BRANCH         || true # allow the branch to exist already
      git remote add $DEVELOPER_NAME $_GITURL || true # allow the remote to exist already
      if [ -d .git ]; then # TODO handle submodules
        template_file=.git/OVERLAY_COMMIT_TEMPLATE
        printf 'Adapt to rocq-prover/rocq#%s (short decription here)\n' "$PR_NUMBER" > "$template_file"

        # don't override config if already set, maybe the user prefers something else
        if ! git config --get --local commit.template; then
          git config --local commit.template "$template_file"
        fi
      fi
    )

}

if [ $# -lt 3 ]; then
  echo "usage: $0 github_username pr_number contrib1 ... contribN"
  exit 1
fi

set +x
. dev/ci/ci-basic-overlay.sh
set -x

DEVELOPER_NAME=$1
shift
PR_NUMBER=$1
shift
OVERLAY_BRANCH=$(git rev-parse --abbrev-ref HEAD)
OVERLAY_FILE=$(mktemp overlay-XXXX)

# Create the overlay file
> "$OVERLAY_FILE"

skipped_repos=

# We first try to build the contribs
while test $# -gt 0
do
    _CONTRIB_NAME=$1
    _CONTRIB_GITURL=${_CONTRIB_NAME}_CI_GITURL
    _CONTRIB_GITURL=${!_CONTRIB_GITURL}
    _CONTRIB_SUBMODULE_GITURL=${_CONTRIB_NAME}_CI_SUBMODULE_GITURL
    _CONTRIB_SUBMODULE_GITURL=${!_CONTRIB_SUBMODULE_GITURL}
    _CONTRIB_SUBMODULE_BRANCH=${_CONTRIB_NAME}_CI_SUBMODULE_BRANCH
    _CONTRIB_SUBMODULE_BRANCH=${!_CONTRIB_SUBMODULE_BRANCH}
    if [[ -n "${_CONTRIB_SUBMODULE_GITURL}" ]]; then
        _CONTRIB_GITURL="${_CONTRIB_SUBMODULE_GITURL}"
    fi
    echo "Processing Contrib $_CONTRIB_NAME"
    shift

    # check _CONTRIB_GIT exists and it is of the from github...

    _CONTRIB_DIR=_build_ci/$_CONTRIB_NAME

    # extract the relevant part of the repository
    if [[ $_CONTRIB_GITURL == https://github.com/*/* ]]; then
        _CONTRIB_GITSUFFIX=${_CONTRIB_GITURL#https://github.com/*/}
        _CONTRIB_GITURL="https://github.com/$DEVELOPER_NAME/$_CONTRIB_GITSUFFIX"
        _CONTRIB_GITPUSHURL="git@github.com:$DEVELOPER_NAME/${_CONTRIB_GITSUFFIX}.git"
    else
        skipped_repos="$skipped_repos $_CONTRIB_NAME"
        continue
    fi

    DOWNLOAD_ONLY=1 make ci-$_CONTRIB_NAME || true
    setup_contrib_git $_CONTRIB_DIR $_CONTRIB_GITPUSHURL

    echo "overlay ${_CONTRIB_NAME} $_CONTRIB_GITURL $OVERLAY_BRANCH $PR_NUMBER" >> $OVERLAY_FILE
    if [ -n "${_CONTRIB_SUBMODULE_BRANCH}${_CONTRIB_SUBMODULE_GITURL}" ]; then
        echo "# Make PRs against ${_CONTRIB_SUBMODULE_GITURL} base branch ${_CONTRIB_SUBMODULE_BRANCH}" >> $OVERLAY_FILE
    fi
    if [ $# -gt 0 ]; then echo "" >> $OVERLAY_FILE; fi
done

# Copy to overlays folder.
PR_NUMBER=$(printf '%05d' "$PR_NUMBER")
mv $OVERLAY_FILE dev/ci/user-overlays/$PR_NUMBER-$DEVELOPER_NAME-${OVERLAY_BRANCH///}.sh

if [ -n "$skipped_repos" ]; then
    >&2 echo "Skipped non-github repos: $skipped_repos"
    exit 1
fi
