#!/bin/bash
cd "$(dirname "$0")"

CONF_DIR="./nginx/conf.d/"
SLICE_DIR="./nginx/conf.d/slice/"
TPL_DIR="./nginx/template.d/"
CERTBOT_DIR="./certbot/etc/live/"

if [ $# = 0 ]; then BATCH_MODE=0; else BATCH_MODE=1; fi

exit_by_error() { echo "$1"; exit 1; }
read_value() { read -rp "> " "$1" || exit_by_error $'\n'"Failed to read!"; }

# Step 1: Enter the priority of config (01 to 99)
PRIORITY=
if [ "$BATCH_MODE" = 1 ]; then
	[ $# -gt 0 ] || exit_by_error "$0: Miss priority!"
	[[ "$1" =~ ^[0-9]{2}$ ]] || exit_by_error "$0: Invalid priority: \"$1\""
	PRIORITY="$1"; shift
else
	PRIORITY=50
	echo "Enter the priority of config: (01 to 99) (Default: ${PRIORITY})"
	while true; do
		read_value input
		[ -n "$input" ] || break
		[[ "$input" =~ ^[0-9]{2}$ ]] || { echo "Invalid priority!"; continue; }
		PRIORITY="$input"; break
	done
fi

# Step 2: Enter your domain
DOMAIN=
if [ "$BATCH_MODE" = 1 ]; then
	[ $# -gt 0 ] || exit_by_error "$0: Miss domain!"
	[ -n "$1" ] || exit_by_error "$0: Invalid domain: \"\""
	DOMAIN="$1"; shift
else
	echo "Enter your domain: (e.g. example.com)"
	while [ -z "$DOMAIN" ]; do
		read_value DOMAIN
		[ -n "$DOMAIN" ] || echo "Invalid domain!"
	done
fi

# Step 3: Enter your template
TPL_NAME=
if [ "$BATCH_MODE" = 1 ]; then
	[ $# -gt 0 ] || exit_by_error "$0: Miss template name!"
	[ -n "$1" ] || exit_by_error "$0: Invalid template name: \"\""
	[ -f "${TPL_DIR}${1}.conf" ] || exit_by_error "$0: Miss template file: \"${TPL_DIR}${1}.conf\""
	TPL_NAME="$1"; shift
else
	tpl_names=( $(find "$TPL_DIR" -type f -name "*.conf" -exec basename \{\} .conf \; | sort) )
	max_idx="$(( ${#tpl_names[@]} - 1 ))"
	[ "$max_idx" -ge 0 ] || exit_by_error  "Miss templates in directory ${TPL_DIR} !"
	echo "Available templates:"
	i=0; for tpl in "${tpl_names[@]}"; do
		echo "  $i) ${tpl} : $(sed -nE 's/^### *\{\{desc\}\} *(.*)$/\1/p' "${TPL_DIR}${tpl}.conf")"
		i=$((1+$i))
	done
	echo "Select a template (0 to ${max_idx}):"
	while true; do
		read_value input
		[[ "$input" =~ ^[0-9]{1,3}$ ]] && [ "${tpl_names[$input]}" ] \
			|| { echo "Invalid number!"; continue; }
		TPL_NAME="${tpl_names[$input]}"; break
	done
fi
TPL_FILE="${TPL_DIR}${TPL_NAME}.conf"

# Step 4: Setup template arguments
TPL_PARAM_LINES=()
TPL_PARAM_PAIRS=()
PORT=
while read -r line; do
	[ -z "$line" ] || TPL_PARAM_LINES+=("$line")
done <<<"$(sed -nE 's/^### *(\{\{params.*)$/\1/p' "$TPL_FILE")"
i=0; for line in "${TPL_PARAM_LINES[@]}"; do
	name="${line%% *}"
	value=
	if [ "$BATCH_MODE" = 1 ]; then
		[ $# -gt 0 ] || exit_by_error "$0: Miss value of \"${name}\" !"
		[ -n "$1" ] || exit_by_error "$0: Invalid value of \"${name}\": \"$1\""
		value="$1"; shift
	elif [ "$name" = "{{params.slice}}" ]; then
		# For convenience, select a slice instead of enter a slice name
		slice_names=( $(find "$SLICE_DIR" -type f -name "*.slice" ! -name '_*' -exec basename \{\} .slice \; | sort) )
		max_idx="$(( ${#slice_names[@]} - 1 ))"
		[ "$max_idx" -ge 0 ] || exit_by_error "Miss slices in directory ${TPL_DIR} !"
		echo "Available slices:"
		j=0; for slice in "${slice_names[@]}"; do
			echo "  $j) ${slice}"
			j=$((1+$j))
		done
		echo "Select a slice (0 to ${max_idx}):"
		while true; do
			read_value input
			[[ "$input" =~ ^[0-9]{1,3}$ ]] && [ -n "${slice_names[$input]}" ] \
				|| { echo "Invalid number!"; continue; }
			value="${slice_names[$input]}"; break
		done
	else
		echo "Set ${line}"
		value="$(echo "$line" | sed -nE 's/^.*\(Default: *([^\)]+)\).*$/\1/p')"
		read_value input
		[ -z "$input" ] || value="$input"
	fi
	TPL_PARAM_PAIRS+=("$name" "$value")
	if [ "$name" = "{{params.port}}" ]; then
		PORT="${value##*:}"
	fi
	i=$((1+$i))
done

TARGET_NAME="${DOMAIN}${PORT:+-$PORT}"
TARGET_FILE="${CONF_DIR}${PRIORITY}-${TARGET_NAME}.conf"

handle_template() {
	local tpl_file="${TPL_DIR}${1}.conf"; shift
	[ -f "$tpl_file" ] || { echo "$0: Miss template file: ${tpl_file}"; return 1; }
	local awk_vars=()
	local awk_script=
	i=0; while [ $# -gt 0 ]; do
		awk_vars+=(-v "n${i}=${1}" -v "v${i}=${2}")
		awk_script="${awk_script} gsub(n${i}, v${i}, s);"
		shift 2
		i=$((1+$i))
	done
	awk_script="!/^###/ { s=\$0; ${awk_script} print s; }"
	awk -F $'\n' "${awk_vars[@]}" "$awk_script" "$tpl_file" || return 1
}

deploy_site_by_tpl() {
	local tpl_name="$1"; shift

	# Handle template and save config
	handle_template "$tpl_name" "{{domain}}" "$DOMAIN" "$@" > "$TARGET_FILE" \
		|| { echo "$0: Failed to handle template!"; return 1; }

	# Reload nginx
	./nginx-reload.sh || { echo "$0: Failed to reload nginx!"; return 1; }
}

deploy_target_site() {
	# Apply for an ssl certificate
	if [ -z "${TPL_NAME##*.https}" -o -z "${TPL_NAME##*.https-}" ] \
		&& [ ! -f "${CERTBOT_DIR}${DOMAIN}/privkey.pem" ]
	then
		# Deploy a simple http site for certbot
		deploy_site_by_tpl "welcome.http" || return 1

		# Run certbot certonly
		./certbot.sh certonly -d "$DOMAIN" \
			|| { echo "$0: Certbot certonly failed: \"${DOMAIN}\""; return 1; }
	fi

	# Deploy target site
	deploy_site_by_tpl "$TPL_NAME" "${TPL_PARAM_PAIRS[@]}" || return 1
}

echo_vars() {
	echo "========"
	echo "PRIORITY: [$PRIORITY]"
	echo "DOMAIN: [$DOMAIN]"
	echo "PORT: [$PORT]"
	echo "TPL_NAME: [$TPL_NAME]"
	echo "TPL_FILE: [$TPL_FILE]"
	echo "TPL_PARAM_PAIRS: [${TPL_PARAM_PAIRS[*]}]"
	echo "TARGET_NAME: [$TARGET_NAME]"
	echo "TARGET_FILE: [$TARGET_FILE]"
	echo "--------"
	handle_template "$TPL_NAME" "{{domain}}" "$DOMAIN" "${TPL_PARAM_PAIRS[@]}"
	echo "========"
}
#echo_vars


# Rename conflicting config (xxx.conf to xxx.conf.bak-tmp)
find "$CONF_DIR" -type f -name "??-${TARGET_NAME}.conf" -exec mv -f \{\} \{\}.bak-tmp \;

# Do deploy
deploy_target_site || {
	# Restore:
	# 1. Remove target file if exists
	rm -f "$TARGET_FILE"
	# 2. Restore conflicting config (xxx.conf.bak-tmp to xxx.conf)
	find "$CONF_DIR" -type f -name "*.bak-tmp" \
		-exec bash -c 'path="{}"; mv -f "$path" "${path%.bak-tmp}"' \;
	# 3. Reload nginx
	./nginx-reload.sh
	exit 1
}

# Backup conflicting config (xxx.conf.bak-tmp to xxx.conf.bak-YYYY-MMDD-hhmmss)
BACKUP_SUFFIX=".bak-$(date +%Y-%m%d-%H%M%S)"
find "$CONF_DIR" -type f -name "*.bak-tmp" -exec bash -c "
	src='{}'
	old=\"\${src%.bak-tmp}\"
	bkp=\"\${old}${BACKUP_SUFFIX}\"
	if [ -z \"\$(diff '{}' \"$TARGET_FILE\" 2>/dev/null)\" ]; then
		rm -f '{}'
		echo \"Remove old: \$old\"
	else
		mv -f '{}' \"\$bkp\"
		echo \"Backup old: \$bkp\"
	fi
" \;
echo "New: ${TARGET_FILE}"
echo "Done."