#!/usr/bin/env bash
set -euo pipefail


## CONSTANTS ##
readonly CODEBASE_DIR="/opt/etebase"
readonly DATA_DIR="/opt/etebase-data"


## HANDLE EXIT SIGNALS ##
trap trap_exit EXIT SIGINT SIGTERM
trap_exit(){
	if [[ "${pid:+x}" ]]; then
		kill -- $pid 2> /dev/null || true
		q=0
		while proc_running $pid; do
			q=$(( q + 1 ))
			snore 1
			if [[ "$q" -ge 15 ]]; then
				echo "Sending kill to Etebase" 1>&2
				kill -s KILL -- $pid 2> /dev/null || true
				break
			fi
		done
	fi
	exit 0
}



#
# LIB: Efficient sleep (does not create a new process).
#
snore(){
	local IFS
	[[ -n "${_snore_fd:-}" ]] || exec {_snore_fd}<> <(:)
	read ${1:+-t "$1"} -u $_snore_fd || true
}



#
# HELPER: Check whether given pid is running.
# 
# @param $1		Process ID.
# 
# @exit			0:		Process is running
#				1:		Process is not running.
#
proc_running(){
	# try reading state
	local state_path="/proc/$1/stat"
	[[ ! -f "$state_path" ]] && return 1
	local state
	state=$(cat "$state_path" 2> /dev/null | cut -d ' ' -f3) || return 1
	
	# parse state
	case "$state" in
		R|S|D|Z|W|W|P|I) return 0;;
		*) return 1;;
	esac
}



#
# HELPER: Initialize etebase config files.
#
etebase_config_init(){
	## MAYBE CREATE SYMLINK ##
	if [[ ! -h "${CODEBASE_DIR}/etebase-server.ini" ]]; then
		ln -s "${DATA_DIR}/server.ini" "${CODEBASE_DIR}/etebase-server.ini"
	fi
	
	
	## MAYBE WRITE DEFAULT FILE ##
	if [[ ! -f "${DATA_DIR}/server.ini" ]]; then
		echo "[global]
debug = false
secret_file = ${DATA_DIR}/secret.txt
static_root = ${CODEBASE_DIR}/static
media_root = ${DATA_DIR}/media
;language_code = en-us
;time_zone = UTC

[allowed_hosts]
allowed_host1 = *

[database]
engine = django.db.backends.sqlite3
name = ${DATA_DIR}/db.sqlite3" > "${DATA_DIR}/server.ini"
	fi
}



#
# HELPER: Initialize django app.
#
etebase_app_init(){
	## RUN MIGRATIONS ##
	.venv/bin/python3 ./manage.py migrate
	
	
	## MAYBE COPY STATIC FILES ##
	if [[ ! -d "${CODEBASE_DIR}/static" ]]; then
		.venv/bin/python3 ./manage.py collectstatic
	fi
	
	
	## OVERWRITE INDEX PAGE ##
	cat /index.html > "${CODEBASE_DIR}/etebase_server/templates/success.html"
}





## SET UP DATA DIRECTORIES ##
mkdir -p "$DATA_DIR"
mkdir -p "${DATA_DIR}/media"


## INITIALIZE CONFIG ##
etebase_config_init


## INITIALIZE DJANGO APP ##
etebase_app_init


## RUN SERVER ##
.venv/bin/uvicorn etebase_server.asgi:application --host 0.0.0.0 --port 80 & pid=$!
wait $pid