#!/bin/sh

# ----------------- Helper functions

log()
{
	echo $@
}

err()
{
	log $@
}

fatal()
{
	err $@
	exit 1
}

counter()
{
	[ "$n_projects" != 1 ] || return
	echo " [$cur/$n_projects]"
}

marker()
{
	log "# -------------$(counter) $@"
}

fat_marker()
{
	if [ "$n_projects" = 1 ]; then
		marker "$@"
		return
	fi
	log "# ====================================================$(counter) $@"
}

#
# Guess and set the following global variables:
#
# - projects_dir: The directory all projects are contained in
# - project_dirs: A space separated list of all directories containing a project
# - n_projects: the number of projects
#
set_global_variables()
{
	[ "$projects_dir" ] || {
		projects_dir=`pwd`
		# If we're in a toplevel directory, suppose projects_dir == project_dirs,
		# i.e. we only want to target this Git repo
		if [ ! -d .git ]; then
			while [ ! -r Makefile ] || ! grep -q some-random-string-to-id-this-makefile Makefile; do
				[ "$projects_dir" = / ] && fatal "Failed to find projects directory"
				projects_dir=`dirname $projects_dir`
			done
		fi
	}

	[ "$project_dirs" ] || {
		if [ "$PGIT_SH_PROJECTS" ]; then
			project_dirs="$PGIT_SH_PROJECTS"
		else
			project_dirs=`(cd $projects_dir; ls -d */.git 2>/dev/null | sed 's%/.git%%')`
		fi
	}
	n_projects=`echo $project_dirs | wc -w`
}

run_git()
{
	marker git "$@"
	git "$@"
}

# ----------------- Commands

cmd_run()
(
	local d
	local cmd=$1
	shift

	set_global_variables
	cd $projects_dir

	if [ "$PGIT_KEEP_GOING" != y ]; then set -e; fi
	for d in $project_dirs; do
		cur=`expr $cur + 1`
		run_git -C $d $cmd "$@"
	done
)

cmd_exec()
(
	local d

	set_global_variables
	cd $projects_dir

	if [ "$PGIT_KEEP_GOING" != y ]; then set -e; fi
	for d in $project_dirs; do
		cur=`expr $cur + 1`
		fat_marker $d: "$@"
		(
			cd $d
			"$@"
		)
	done
)

cmd_commit()
(
	local d do_cvs

	if [ "$1" = --cvs ]; then
		do_cvs=true
		shift
	fi

	set_global_variables
	cd $projects_dir

	if [ "$PGIT_KEEP_GOING" != y ]; then set -e; fi
	for d in $project_dirs; do
		cur=`expr $cur + 1`
		if run_git -C $d diff-index --quiet HEAD --; then
			log "Nothing to commit"
			continue
		fi
		run_git -C $d commit "$@"
	done
)

cmd_get()
(
	run_clone() {
		local url="$1"
		local p="$2"
		run_git $GIT_GLOBAL_OPTS clone "$url" "$p"
		if [[ "$GIT_GLOBAL_OPTS" =~ proactiveAuth ]]; then
			run_git -C $p config set http.proactiveAuth basic
		fi
	}

	local remote_base="$global_remote_base"
	local remote_subpath="$global_remote_subpath"
	local whoami="$(id -un)"
	set_global_variables
	cd $projects_dir
	local projects="$PGIT_SH_PROJECTS"
	local ignore="$PGIT_IGNORE"
	local this_dir="${0%/*}"
	local jw_projects="/usr/bin/python3 $this_dir/jw-pkg.py"
	local create_remote_user_repos=false
	local long_opts="create-remote-user-repos"
	local refspec_arg refspec=()
	long_opts="$long_opts,refspec:"

	local opts
	opts=$(getopt -o C --long "$long_opts" -n get -- "$@") || fatal "Failed to parse options $@"
	eval set -- "$opts"
	while [ "$1" != -- ]; do
	case "$1" in
		-C | --create-remote-user-repos)
			create_remote_user_repos=true
			;;
		--refspec)
			refspec_arg="$2"
			refspec=(${refspec_arg//:/ })
			shift
			;;
		*)
			fatal "Unknown option $1"
			;;
	esac
	shift
	done

	local git_srv_admin="$SSH $remote_user@git.janware.com /opt/jw-pkg/bin/git-srv-admin.sh"
	local from_user="${refspec[0]}"
	[ "$from_user" ] || from_user=$whoami

	if [ -z "$projects" ]; then
		projects=`$jw_projects projects list-repos --from-owner $from_user $remote_base`
		[ "$?" != 0 ] && exit 1
	fi

	if [ "$remote_user" ]; then
		[ "${remote_base/@/}" = "${remote_base}" ] || fatal "Specified both --login $remote_user and user in URL $remote_base"
		remote_base=$(echo $remote_base | sed "s|://|://$remote_user@|")
	fi

	n_projects=`echo $projects | wc -w`
	if [ "$PGIT_KEEP_GOING" != y ]; then set -e; fi
	local project_dir
	for project_dir in $projects; do
		local project_name=$(readlink -f $project_dir | xargs basename)
		echo $ignore | grep -q "\b$project_name\b" && continue
		cur=`expr $cur + 1`
		local pull_url=$remote_base/$from_user$remote_subpath/$project_name
		local push_url=$remote_base/$remote_user$remote_subpath/$project_name
		local cur_ref=$(git -C $project_dir rev-parse --abbrev-ref HEAD)
		local remote_name="jw-$from_user"
		local from_ref="${refspec[1]}"
		local to_ref="${refspec[2]}"
		[ "$from_ref" ] || from_ref=master
		[ "$from_user" = "$remote_user" ] && remote_name="origin"
		[ "$to_ref" = "current-branch" ] && to_ref=$cur_ref
		[ "$from_ref" = "current-branch" ] && from_ref=$cur_ref
		local log_refspec="$from_user:$from_ref"
		[ "$to_ref" ] && log_refspec="$log_refspec -> $to_ref"
		[ "$refspec_arg" -a "$refspec_arg" != "$from_user:$from_ref:$to_ref" ] && log_refspec="$log_refspec ($refspec_arg)"
		fat_marker "Getting project $project_name from $log_refspec"
		if [ -d $project_dir ]; then
			run_git -C $project_dir remote | grep -q "^$remote_name$" || {
				run_git -C $project_dir remote add $remote_name $pull_url
				[ "$from_user" = "$remote_user" ] || run_git -C $project_dir remote set-url --push $remote_name no_push
			}
			run_git -C $project_dir fetch --prune --recurse-submodules=on-demand $remote_name $from_ref
			run_git -C $project_dir submodule foreach --recursive 'git fetch --tags -f origin'
			if [ "$to_ref" ]; then
				run_git -C $project_dir rebase --autostash $remote_name/$from_ref $to_ref
				run_git -C $project_dir merge --ff-only $remote_name/$from_ref $to_ref
			fi
		else
			run_clone $remote_base/$from_user$remote_subpath/$project_name $project_dir
			if [ "$from_user" != "$remote_user" ]; then
				run_git -C $project_dir remote rename origin $remote_name || fatal "Failed to rename remote in $project_dir"
				run_git -C $project_dir remote set-url --push $remote_name no_push
				if [ $create_remote_user_repos = true ]; then
					$git_srv_admin -u $remote_user -j create-personal-project $project_name
					run_git -C $project_dir remote add origin $push_url
					run_git -C $project_dir push --recurse-submodules=on-demand origin master
					$git_srv_admin -u $remote_user -j update-descriptions $project_name
					run_git -C $project_dir branch --set-upstream-to origin/master master
				fi
			fi
		fi
		run_git -C $project_dir submodule update --init --recursive || fatal "git submodule update failed in $project_dir"
	done
)

cmd_diff()
(
	local d
	set_global_variables
	cd $projects_dir
	for d in $project_dirs; do
		cur=`expr $cur + 1`
		# marker $d
		run_git -C $d diff --src-prefix=$d/ --dst-prefix=$d/ "$@"
	done
)

echo "running $0 $@ GIT_SSH=$GIT_SSH" >&2

cur=0
SSH=ssh
[ "$GIT_SSH" ] && SSH=$GIT_SSH
global_remote_base="ssh://git.janware.com/srv/git"

while [ "${1:0:1}" = - ]; do
	case "$1" in
		'--remote-base')
			global_remote_base="$2"
			shift
			;;
	esac
	shift
done

# Only janware.com ssh git supports subdirectories below users
if [[ "$global_remote_base" =~ git.janware.com ]]; then
	global_remote_subpath="/proj"
else
	global_remote_subpath=""
fi

cmd=$1
shift

remote_user=$(id -un)
while [ "${1:0:1}" = - ]; do
	case $1 in
		'--login')
			remote_user="$2"
			shift 2
			;;
		*)
			break
			;;
	esac
done

case $cmd in
	get|diff|commit|exec)
		cmd_${cmd//-/_} "$@"
		;;
	*)
		cmd_run $cmd "$@"
		;;
esac