#!/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.bash
source "$(dirname "${BASH_SOURCE[0]}")/util.bash"

# shellcheck source=lib/logging.bash
source "$(dirname "${BASH_SOURCE[0]}")/logging.bash"

main() {
	debug "$BASHTARD_NAME/main" "Running from $BASHTARD_LIBDIR"
	debug "$BASHTARD_NAME/main" "Configuration dir is at $BASHTARD_ETCDIR"
	debug "$BASHTARD_NAME/main" "> $0 $*"

	[[ -z $1 ]] && usage && exit 2

	export BASHTARD_COMMAND="$1" ; shift

	debug "$BASHTARD_NAME/main" "Handling subcommand '$BASHTARD_COMMAND'"

	subcommand_src="$BASHTARD_LIBDIR/subcommands/$BASHTARD_COMMAND.bash"

	debug "$BASHTARD_NAME/main" "Checking $subcommand_src"

	if [[ ! -f $subcommand_src ]]
	then
		debug "$BASHTARD_NAME/main" "No script found to handle action, showing usage"
		usage
		exit 2
	fi

	# Declare some global variables
	declare -A BASHTARD_PLATFORM

	# Figure out system details
	debug "$BASHTARD_NAME/main" "Discovering system information"
	discover_system

	# Export BASHTARD_ variables
	export BASHTARD_PLATFORM

	# Source the file defining the subcommand.
	debug "$BASHTARD_NAME/main" "Sourcing $subcommand_src"
	source "$subcommand_src"

	# Maintain our own tempdir
	export TMPDIR="$BASEDIR/tmp/$RANDOM"
	mkdir -p -- "$TMPDIR"
	debug "$BASHTARD_NAME/main" "\$TMPDIR set to $TMPDIR"

	# Actually perform the subcommand
	debug "$BASHTARD_NAME/main" "Running subcommand '$BASHTARD_COMMAND'"
	subcommand "$@"
	local subcommand_exit=$?

	# Clean up if necessary
	if [[ -z $BASHTARD_MESSY ]]
	then
		debug "$BASHTARD_NAME/main" "Cleaning up tempfiles at $TMPDIR"
		rm -rf -- "$TMPDIR"
	fi

	## Use the subcommand's exit code
	exit $subcommand_exit
}

usage() {
	local playbooks
	local playbook_length
	local playbook_longest=0

	cat <<EOF
Usage:
	$BASHTARD_NAME -h
	$BASHTARD_NAME add <playbook>
	$BASHTARD_NAME bootstrap [repository]
	$BASHTARD_NAME del <playbook>
	$BASHTARD_NAME ssh <command>
	$BASHTARD_NAME sync [playbook]
	$BASHTARD_NAME sysinfo

Perform maintenance on your infra.

Commands:
	add        Add a configuration playbook to this machine.
	bootstrap  Bootstrap the $BASHTARD_NAME configuration system.
	del        Remove a configuration playbook from this machine.
	ssh        Run a given command on all known hosts.
	sync       Pull latest changes through git, and synchronize all added
	           playbooks.
	sysinfo    Show gathered information about this system.

Playbooks:
EOF

	# Find all playbooks
	mapfile -t playbooks < <(find \
		"$BASHTARD_ETCDIR/playbooks.d"/* \
		-maxdepth 0 \
		-type d \
	)

	# Find longest playbook name
	for playbook in "${playbooks[@]}"
	do
		playbook_length="$(printf "%s" "$(basename "$playbook")" | wc -c)"

		if (( playbook_longest < playbook_length ))
		then
			playbook_longest=$playbook_length
		fi
	done

	# Render playbook descriptions
	for playbook in "${playbooks[@]}"
	do
		printf "\t%-${playbook_longest}s  %s\n" \
			"$(basename "$playbook")" \
			"$(cat "$playbook/description.txt")"
	done
}

# Discover information about the system. If any bugs are reported and you want
# more information about the system the user is running on, additional checks
# can be added here, and the user will simply have to include the output of the
# sysinfo command in their message to you.
discover_system() {
	BASHTARD_PLATFORM["os"]="$(discover_system_os)"
	BASHTARD_PLATFORM["arch"]="$(discover_system_arch)"
	BASHTARD_PLATFORM["version"]="$(discover_system_version)"
	BASHTARD_PLATFORM["term"]="$TERM"
	BASHTARD_PLATFORM["fqdn"]="$(hostname -f)"

	# When on a Linux-using OS, check for the specific distribution in use.
	if [[ ${BASHTARD_PLATFORM[os]} == *"linux"* ]]
	then
		BASHTARD_PLATFORM["distro"]="$(discover_system_distro)"
	fi

	BASHTARD_PLATFORM[key]="$(discover_system_key)"
}

discover_system_arch() {
	uname -m
}

discover_system_distro() {
	if [[ -f /etc/os-release ]]
	then
		(
			source /etc/os-release
			printf "%s" "$NAME" \
				| awk '{print tolower($0)}' \
				| sed 's@[/+ ]@_@g'
		)
		return
	fi

	crit "No /etc/os-release found. Are you sure you're on a sane GNU+Linux distribution?"

	if command -v pacman > /dev/null
	then
		warn "$BASHTARD_NAME/main" "Found pacman, assuming Archlinux as distro."
		printf "%s" "archlinux"
		return
	fi
}

discover_system_version() {
	printf "%s" "$(uname -r | awk '{print tolower($0)}')"
}

discover_system_key() {
	local key

	key+="${BASHTARD_PLATFORM[os]}"

	if [[ ${BASHTARD_PLATFORM[distro]} ]]
	then
		key+="-${BASHTARD_PLATFORM[distro]}"
	fi

	printf "%s" "$key"
}

discover_system_os() {
	if command -v uname > /dev/null
	then
		printf "%s" "$(uname -s | awk '{print tolower($0)}' | sed 's@[/+ ]@_@g')"
		return
	fi
}

main "$@"