#!/bin/bash

GIT_SYNCD_CONFIG_DIR=${GIT_SYNCD_CONFIG_DIR:-"$HOME/.config/git-sync"}
GIT_SYNCD_CONFIG=${GIT_SYNCD_CONFIG:-"$GIT_SYNCD_CONFIG_DIR/syncd.rc"}

git_syncd=$0

git_syncd_repos=()

# auto sync exclude regex pattern
declare -g -A git_syncd_exclude=()

# maximum time seconds between fetching changes and syncing
git_syncd_default_sync_timeout=600
declare -g -A git_syncd_sync_timeout=()

# number of seconds to wait after deteced change to push
git_syncd_default_sync_delay=300
declare -g -A git_syncd_sync_delay=()

sync() {
	echo "starting sync.."
	cd "$repo" && git-sync -n -s || notify-send "Sync failed for $repo"
}

watcher() {
	repo=$1
	echo $repo ${git_syncd_exclude[@]} ${git_syncd_exclude[$repo]}
	exclude=${git_syncd_exclude[$repo]:-'\.git'}
	sync_delay=${git_syncd_sync_delay[$repo]:-$git_syncd_default_sync_delay}
	sync_timeout=${git_syncd_sync_timeout[$repo]:-$git_syncd_default_sync_timeout}
	sync "$repo"
	timeout=$sync_timeout
	while true; do
		if [ ! -e "$repo" ]; then
			echo "Repo does not exist"
			echo "sleeping (${timeout}s)"
			sleep $timeout
			continue
		fi
		echo "watching (${timeout}s)"
		file=$(timeout "$timeout" wd "$repo" inotifywait "." -r \
			-e modify,move,create,delete --exclude "$exclude" 2>/dev/null)
		rc=$?
		if [ ! -z "$file" ]; then
			echo "inotify wake: $file"
			timeout=$sync_delay
		elif [ $rc -eq 124 ]; then
			sync "$repo"
			timeout=$sync_timeout
		fi
		sleep 1
	done
}

log_prefix() {
	repo="$1"
	repo_name=$(basename "$repo")
	repo_dir_name=$(basename $(dirname "$repo"))
	while read -r line; do
		prefix="$(date "+%Y-%m-%d %T")" #$repo_dir_name/$repo_name"
		prefix="$(echo "$prefix" | tr -d "\"" | tr -d "'")"
		echo "[$prefix] $line"
	done
}

kill_all() {
	pkill -A -9 git-syncd
}

git_syncd_watchers=()
kill_watchers() {
	kill_all
	return
	fail=0
	for pid in "${git_syncd_watchers[@]}"; do
		echo "killing $pid.." >&2
		pkill -P "$pid" &>/dev/null
		waitpid -t 10 "$pid" &>/dev/null
		kill -0 -P "$pid" &>/dev/null && notify-send "Failed to kill git-syncd watcher" && fail=1
	done
	[ $fail -ne 0 ] && exit 1
	git_syncd_watchers=()
}
start_watchers() {
	for repo in "${git_syncd_repos[@]}"; do
		echo "watching '$repo'.."
		$git_syncd watch "$repo" &
		sleep 1 # wait a bit
		git_syncd_watchers+=($!)
	done
}

load_config() {
	git_syncd_repos=()
	declare -g -A git_syncd_exclude=()
	declare -g -A git_syncd_sync_delay=()
	declare -g -A git_syncd_sync_timeout=()
	if [ -e "$GIT_SYNCD_CONFIG" ]; then
		echo "sourcing '$GIT_SYNCD_CONFIG'.."
		source "$GIT_SYNCD_CONFIG"
	fi
}

if [ "$1" = "watch" ]; then
	shift
	repo="$1"; shift
	repo_dir_name="$(basename $(dirname "$repo"))"
	repo_name="$(basename "$repo")"
	log_path="$HOME/.log/git-sync/$repo_dir_name"
	mkdir -p "$log_path"
	load_config
	watcher "$repo" 2>&1 | log_prefix "$repo" > "$log_path/$repo_name"
	exit
fi

load_config
trap kill_all EXIT
start_watchers
while true; do
	file=$(inotifywait --format "%w%f" -e modify,delete "$GIT_SYNCD_CONFIG")
	if [ ! -z "$file" ]; then
		mod_path="$(realpath "$file" 2>/dev/null)"
		config_path="$(realpath "$GIT_SYNCD_CONFIG" 2>/dev/null)"
		echo "config $mod_path $config_path"
		if [ "$mod_path" = "$config_path" -o "$mod_path" = "$config_path~" ]; then
			kill_watchers
			load_config
			start_watchers
		fi
	fi
	sleep 2
done