#/bin/bash
# This script was indeed self-updated!

# Catch signals so we don't leave zombie tasks behind if we Ctrl^C
# No idea why but it seems to prevent the script from working? Disable!
#trap "exit" INT TERM ERR
#trap "kill 0" EXIT

BASEDIR="$HOME/.git-build"

# Default logging levels (error is always enabled)
INFO=1
DEBUG=0

# Extract two letters from $LANG
locale="${LANG:0:2}"

# Initialize translations
[ -f i18n/$locale.json ] && locale_strings="$(cat i18n/$locale.json)" || locale_strings="$(cat i18n/en.json)"

# Takes one argument, looks up translation
trans() {
    res="$(echo "$locale_strings" | jq ".$1")"
    if [[ "$res" = "" ]]; then
        echo "ERROR: Failed to translate $1"
        exit 1
    fi
    res=${res#"\""}
    res=${res%"\""}
    echo -n "$res"
}

# We set custom logging functions so that later we can decorate stuff
warn() {
    [[ $INFO = 1 ]] && echo -e "\e[33m$(trans warning)\e[0m$(trans $1)" | envsubst > /dev/stderr
}

info() {
    [[ $INFO = 1 ]] && echo "[git-build] $(trans $1)" | envsubst
}

error () {
    echo -e "\e[31m$(trans error)\e[0m$(trans $1)" | envsubst > /dev/stderr
}

debug () {
    [[ $DEBUG = 1 ]] && echo -e "\e[36m$(trans debug)\e[0m$(trans $1)" | envsubst
}

# Logging is done with the LOG="debug|info|error" environment variable
if [ ! -z $LOG ] && [ "$LOG" != "" ]; then
    case $LOG in
        "debug"|"DEBUG")
            DEBUG=1
            ;;
        "error"|"ERROR")
            INFO=0
            ;;
        "info"|"INFO")
            # Default settings
            ;;
        *)
            warn loglevel_bad
            ;;
    esac
fi

run() {
	p_name="$1"
    i18n_task="$p_name" info run
	# Run in background and redirect output to $p_name.log
	(GITBUILDCONF="$CONFDIR" GITBUILDDIR="$BASEDIR" nohup $BASEDIR/$p_name $p_name > $BASEDIR/$p_name.log 2> $BASEDIR/$p_name.err) &
}

# So scripts can know we're still running (for autoupdater)
# TODO needs to be reworked so multiple instances can run at the same time https://tildegit.org/southerntofu/git-build.sh/issues/13
touch $BASEDIR/.LOCK

# Overriden by -f/--force to force rebuild when no update is available
FORCE=0

# Check if we have host-specific config then LOCAL=0
# TODO: maybe we should just match for $BASEDIR/$HOSTNAME directly? Would allow to fallback to global config for multihost setup where one host is not configured.. but is that desired? Also enables to have more folders in $BASEDIR (maybe logs/)
LOCAL=1
for folder in $BASEDIR/*/; do
	# Hidden folders (repos) are ignored by the pattern, so we can assume if a folder is not config/ then there are host-based configs here.
	 [[ "$(basename $folder)" != "config" ]] && LOCAL=0 && break
done

# Pass either local or global config to the task
[[ LOCAL = 1 ]] && CONFDIR=$BASEDIR/config || CONFDIR="$BASEDIR/$HOSTNAME"
export i18n_config="$CONFDIR"
info config

# Find targeted projects from args and extra arguments
PROJECTS=()
for arg in "$@"; do
	if [[ "$arg" = "-f" ]] || [[ "$arg" = "--force" ]]; then
        info force_flag
		FORCE=1
    # Maybe it's a task name and we find a corresponding source?
    # TODO: Support source-less tasks https://tildegit.org/southerntofu/git-build.sh/issues/8
	elif [ -f $BASEDIR/$arg.source ]; then
        export i18n_task="$arg"
        debug found_task
		PROJECTS+=("$arg")
    # Maybe it's a repo URL and we find a corresponding task?
    elif matches="$(grep --files-with-matches --word-regexp "$arg" $BASEDIR/*.source)"; then
        # Iterate over the files found to extract the task name
        IFS= echo "$matches" | while read -r file; do
            task_name="$(basename "$file" .source)"
            # Make sure we don't have a .source file without name lying around, just in case
            if [[ "$task_name" != "" ]]; then
                export i18n_task="$task_name" i18n_source="$arg"
                debug found_url
                PROJECT+=("$task_name")
            fi
        done
    else
        export i18n_arg="$arg"
        error unknown_arg
        exit 1
	fi
done

# If no project argument passed, default to all projects
if [[ ${#PROJECTS[*]} = 0 ]]; then
    info no_task
    # TODO: sourceless tasks
	for file in $BASEDIR/*.source; do
		# Extract the project name from path
        task="$(basename $file .source)"
        export i18n_task="$task"
        debug found_task
		PROJECTS+=("$task")
	done
fi


# TODO: sourceless tasks
for p_name in ${PROJECTS[*]}; do
    # For translations
    export i18n_task="$p_name"
    debug start_proc
	# Check if task should run on host
	if [[ $LOCAL = 0 ]]; then
        if [ -f $BASEDIR/$p_name.host ]; then
            for_host="$(cat $BASEDIR/$p_name.host)"
            if [[ "$for_host" != "$HOSTNAME" ]]; then
                # The task is specifically configured for a different host, ignore
                export i18n_host="$for_host"
                debug skipped
                continue
            fi
		fi
		# The task has a PROJECT.ignore file in host config, ignore
        if [ -f $BASEDIR/$HOSTNAME/$p_name.ignore ]; then
            info host_ignored
            continue
        fi
	fi
	info process
    # TODO: Should be able to switch branch after a repo was cloned
	if [ -f $BASEDIR/$p_name.branch ]; then
       p_branch="$(cat $BASEDIR/$p_name.branch)"
       export i18n_branch="$p_branch"
       info to_branch
    else
        p_branch="master"
        export i18n_branch="$p_branch"
        debug default_branch
    fi
	p_dir="$BASEDIR/.$p_name"
	if [ ! -d $p_dir ]; then
		source="$(cat $BASEDIR/$p_name.source)"
        export i18n_source="$source"
		info clone
		# Don't forget the git submodules!
		if ! git clone --recursive "$source" "$p_dir"; then
            error clone_failed
            exit 1
        fi
		cd $p_dir
		if [[ "$p_branch" != "master" ]]; then
			debug checkout
			if ! git checkout "$p_branch"; then
                error checkout_failed
                exit 1
            fi
		fi
		run $p_name
        # Skip to the next task!
        continue
	fi
    debug already_cloned
	cd "$p_dir"
	# Refresh remote before comparing with local
	git fetch --quiet origin
	git diff --quiet remotes/origin/$p_branch
	if [[ $? != 0 ]]; then
		info pull
		# Update all submodules, for now only when the main repo changed (TODO)
		if ! git pull --quiet --recurse-submodules; then
            error pull_failed
            exit 1
        fi
		run $p_name
	# If no update was found, we can still force rebuild with -f/--force
	elif [[ $FORCE = 1 ]]; then
        debug forcing
		run $p_name
    else
        debug no_update
	fi
done

# TODO: better locking mechanism
rm $BASEDIR/.LOCK