#!/usr/bin/env bash

# SPDX-FileCopyrightText: 2022 Patrick Spek <p.spek@tyil.nl>
#
# SPDX-License-Identifier: AGPL-3.0-or-later

# shellcheck source=lib/util/config.bash
. "$BASHTARD_LIBDIR/util/config.bash"
# shellcheck source=lib/util/pkg.bash
. "$BASHTARD_LIBDIR/util/pkg.bash"
# shellcheck source=lib/util/svc.bash
. "$BASHTARD_LIBDIR/util/svc.bash"

# Change the working directory. In usage, this is the same as using cd,
# however,  it will make additional checks to ensure everything is going fine.
chgdir() {
	debug "bashtard/chgdir" "Changing workdir to $1"
	cd -- "$1" || die "Failed to change directory to $1"
}

# Create a datetime stamp. This is a wrapper around the date utility, ensuring
# that the date being formatted is always in UTC and respect SOURCE_DATE_EPOCH,
# if it is set.
datetime() {
	local date_opts

	date_opts+=("-u")

	# Apply SOURCE_DATE_EPOCH as the date to base off of.
	if [[ $SOURCE_DATE_EPOCH ]]
	then
		date_opts+=("-d@$SOURCE_DATE_EPOCH")
	fi

	date "${date_opts[@]}" +"${1:-%FT%TZ}"
}

# Log a message as error, and exit the program. This is intended for serious
# issues that prevent the script from running correctly. The exit code can be
# specified with -i, or will default to 1.
die() {
	local OPTIND
	local code

	while getopts ":i:" opt
	do
		case "$opt" in
			i) code=$OPTARG ;;
			*) alert "bashtard/die" "Unused argument specified: $opt" ;;
		esac
	done

	shift $(( OPTIND -1 ))

	alert "$@"
	exit "${code:-1}"
}

# Fetch a file from an URL. Using this function introduces a dependency on curl.
fetch_http() {
	local OPTIND
	local buffer

	while getopts ":o:" opt
	do
		case "$opt" in
			o) buffer=$OPTARG ;;
			*) alert "bashtard/fetch_http" "Unused argument specified: $opt" ;;
		esac
	done

	shift $(( OPTIND -1 ))

	[[ -z $buffer ]] && buffer="$(tmpfile)"

	notice "bashtard/fetch_http" "Downloading $1 to $buffer"

	for util in curl wget
	do
		command -v "$util" > /dev/null || continue
		"fetch_http_$util" "$1" "$buffer" || continue
		local exit_code=$?

		printf "%s" "$buffer"
		return $exit_code
	done

	die "bashtard/fetch_http" "Unable to download file over HTTP!"
}

fetch_http_curl() {
	curl -Ls "$1" > "$2"
}

fetch_http_wget() {
	wget --quiet --output-document "$2" "$1"
}

# Check if the first argument given appears in the list of all following
# arguments.
in_args() {
	local needle="$1"
	shift

	for arg in "$@"
	do
		[[ $needle == "$arg" ]] && return 0
	done

	return 1
}

# Join a list of arguments into a single string. By default, this will join
# using a ",", but you can set a different character using -c. Note that this
# only joins with a single character, not a string of characters.
join_args() {
	local OPTIND
	local IFS=","

	while getopts ":c:" opt
	do
		case "$opt" in
			c) IFS="$OPTARG" ;;
			*) warn "bashtard/join_args" "Unused opt specified: $opt" ;;
		esac
	done

	shift $(( OPTIND - 1))

	printf "%s" "$*"
}

# Recursively hash files in a directory, and hashing the output of all those
# hashes again. This results in a single hash representing the state of files
# in a directory. It can be used to check whether contents changed after
# templating files in a given directory.
file_rhash() {
	find "$1" -type f -exec sha1sum {} \; \
		| sha1sum \
		| awk '{ print $1 }'
}

file_template()
{
	local file="$BASHTARD_ETCDIR/playbooks.d/$BASHTARD_PLAYBOOK/share/$1" ; shift
	local sedfile

	sedfile="$(tmpfile)"

	if [[ ! -f $file ]]
	then
		crit "bashtard/template" "Tried to render template from $file, but it doesn't exist"
		return
	fi

	for kv in "$@"
	do
		debug "bashtard/template" "Adding $kv to sedfile at $sedfile"

		key="$(awk -F= '{ print $1 }' <<< "$kv")"

		if [[ -z "$key" ]]
		then
			crit "bashtard/template" "Empty key in '$kv' while rendering $file?"
		fi

		value="$(awk -F= '{ print $NF }' <<< "$kv")"

		if [[ -z "$value" ]]
		then
			crit "bashtard/template" "Empty key in '$kv' while rendering $file?"
		fi

		# shellcheck disable=SC2016
		printf 's@${%s}@%s@g\n' "$key" "$value" >> "$sedfile"
	done

	sed -f "$sedfile" "$file"
}

# Create a temporary directory. Similar to tempfile, but you'll get a directory
# instead.
tmpdir() {
	local dir

	dir="$(mktemp -d)"

	# Ensure the file was created succesfully
	if [[ ! -d "$dir" ]]
	then
		die "bashtard/tmpdir" "Failed to create a temporary directory at $dir"
	fi

	debug "bashtard/tmpdir" "Temporary file created at $dir"

	printf "%s" "$dir"
}

# Create a temporary file. In usage, this is no different from mktemp itself,
# however, it will apply additional checks to ensure everything is going
# correctly, and the files will be cleaned up automatically at the end.
tmpfile() {
	local file

	file="$(mktemp)"

	# Ensure the file was created succesfully
	if [[ ! -f "$file" ]]
	then
		die "bashtard/tmpfile" "Failed to create a temporary file at $file"
	fi

	debug "bashtard/tmpfile" "Temporary file created at $file"

	printf "%s" "$file"
}