#!/bin/bash
#
# bash completion file for core oci-runtime-tool commands
#
# This script provides completion of:
#  - commands and their options
#  - filepaths
#
# To enable the completions either:
#  - place this file in /usr/share/bash-completion/completions
#  or
#  - copy this file to e.g. ~/.oci-runtime-tool-completion.sh and add the line
#    below to your .bashrc after bash completion features are loaded
#    . ~/.oci-runtime-tool-completion.sh
#
# Configuration:
#


# Note for developers:
# Please arrange options sorted alphabetically by long name with the short
# options immediately following their corresponding long form.
# This order should be applied to lists, alternatives and code blocks.

__oci-runtime-tool_previous_extglob_setting=$(shopt -p extglob)
shopt -s extglob

__oci-runtime-tool_pos_first_nonflag() {
	local argument_flags=$1

	local counter=$((${subcommand_pos:-${command_pos}} + 1))
	while [ $counter -le $cword ]; do
		if [ -n "$argument_flags" ] && eval "case '${words[$counter]}' in $argument_flags) true ;; *) false ;; esac"; then
			(( counter++ ))
		else
			case "${words[$counter]}" in
				-*)
					;;
				*)
					break
					;;
			esac
		fi
		(( counter++ ))
	done

	echo $counter
}

# Transforms a multiline list of strings into a single line string
# with the words separated by "|".
# This is used to prepare arguments to __oci-runtime-tool_pos_first_nonflag().
__oci-runtime-tool_to_alternatives() {
	local parts=( $1 )
	local IFS='|'
	echo "${parts[*]}"
}

# Transforms a multiline list of options into an extglob pattern
# suitable for use in case statements.
__oci-runtime-tool_to_extglob() {
	local extglob=$( __oci-runtime-tool_to_alternatives "$1" )
	echo "@($extglob)"
}

# Subcommand processing.
# Locates the first occurrence of any of the subcommands contained in the
# first argument. In case of a match, calls the corresponding completion
# function and returns 0.
# If no match is found, 1 is returned. The calling function can then
# continue processing its completion.
#
# TODO if the preceding command has options that accept arguments and an
# argument is equal ot one of the subcommands, this is falsely detected as
# a match.
__oci-runtime-tool_subcommands() {
	local subcommands="$1"

	local counter=$(($command_pos + 1))
	while [ $counter -lt $cword ]; do
		case "${words[$counter]}" in
			$(__oci-runtime-tool_to_extglob "$subcommands") )
				subcommand_pos=$counter
				local subcommand=${words[$counter]}
				local completions_func=_oci-runtime-tool_${command}_${subcommand}
				declare -F $completions_func >/dev/null && $completions_func
				return 0
				;;
		esac
		(( counter++ ))
	done
	return 1
}

# List groups
__oci-runtime-tool_groups() {
	cut -d: -f 1 /etc/group
}

# List installed hooks
__oci-runtime-tool_hooks() {
	ls /usr/libexec/oci/hooks.d/*
}

# suppress trailing whitespace
__oci-runtime-tool_nospace() {
	# compopt is not available in ancient bash versions
	type compopt &>/dev/null && compopt -o nospace
}

__oci-runtime-tool_complete_log_level() {
	COMPREPLY=( $( compgen -W "
		debug
		error
		fatal
		info
		panic
		warn
	" -- "$cur" ) )
}

__oci-runtime-tool_complete_propagations() {
	COMPREPLY=( $( compgen -W "
		private
		rprivate
		rshared
		rslave
		shared
		slave
	" -- "$cur" ) )
}

# a selection of the available arches that is most likely of interest in the
# context of oci-runtime-tool containers.
__oci-runtime-tool_complete_arches() {
	COMPREPLY=( $( compgen -W "
		386
		amd64
		arm
		arm64
		mips
		mips64
		mips64le
		mipsle
		ppc64
		ppc64le
		s390x
	" -- "$cur" ) )
}

# a selection of the available arches that is most likely of interest in the
# context of oci-runtime-tool containers.
__oci-runtime-tool_complete_seccomp_arches() {
	COMPREPLY=( $( compgen -W "
		x86
		amd64
		x32
		arm
		arm64
		mips
		mips64
		mips64n32
		mipsel
		mipsel64
		mipsel64n32
		ppc
		ppc64
		ppc64le
		s390
		s390x
		parisc
		parisc64
	" -- "$cur" ) )
}

# a selection of the available actions that is most likely of interest in the
# context of oci-runtime-tool containers.
__oci-runtime-tool_complete_seccomp_actions() {
	COMPREPLY=( $( compgen -W "
		SCMP_ACT_ALLOW
		SCMP_ACT_ERRNO
		SCMP_ACT_KILL
		SCMP_ACT_TRACE
		SCMP_ACT_TRAP
	" -- "$cur" ) )
}
__oci-runtime-tool_complete_capabilities() {
	# The list of capabilities is defined in types.go, ALL was added manually.
	COMPREPLY=( $( compgen -W "
		ALL
		AUDIT_CONTROL
		AUDIT_WRITE
		AUDIT_READ
		BLOCK_SUSPEND
		CHOWN
		DAC_OVERRIDE
		DAC_READ_SEARCH
		FOWNER
		FSETID
		IPC_LOCK
		IPC_OWNER
		KILL
		LEASE
		LINUX_IMMUTABLE
		MAC_ADMIN
		MAC_OVERRIDE
		MKNOD
		NET_ADMIN
		NET_BIND_SERVICE
		NET_BROADCAST
		NET_RAW
		SETFCAP
		SETGID
		SETPCAP
		SETUID
		SYS_ADMIN
		SYS_BOOT
		SYS_CHROOT
		SYSLOG
		SYS_MODULE
		SYS_NICE
		SYS_PACCT
		SYS_PTRACE
		SYS_RAWIO
		SYS_RESOURCE
		SYS_TIME
		SYS_TTY_CONFIG
		WAKE_ALARM
	" -- "$cur" ) )
}


# global options that may appear after the oci-runtime-tool command
_oci-runtime-tool_oci-runtime-tool() {
	local options_with_args="
		--log-level
	"

	local boolean_options="
		--help -h
		--host-specific
		--version -v
	"

	local all_options="$options_with_args $boolean_options"

	case "$prev" in
		--log-level)
			__oci-runtime-tool_complete_log_level
			return
			;;
	esac

	case "$cur" in
		-*)
			COMPREPLY=( $( compgen -W "$all_options" -- "$cur" ) )
			;;
		*)
			local counter=$( __oci-runtime-tool_pos_first_nonflag $(__oci-runtime-tool_to_extglob "$options_with_args") )
			if [ $cword -eq $counter ]; then
				COMPREPLY=( $( compgen -W "${commands[*]} help" -- "$cur" ) )
			fi
			;;
	esac
}

_oci-runtime-tool_validate() {
	case "$prev" in
		--path)
			case "$cur" in
				*:*)
					# TODO somehow do _filedir for stuff inside the image, if it's already specified (which is also somewhat difficult to determine)
					;;
				'')
					COMPREPLY=( $( compgen -W '/' -- "$cur" ) )
					__oci-runtime-tool_nospace
					;;
				/*)
					_filedir
					__oci-runtime-tool_nospace
					;;
			esac
			return
			;;
	esac

	case "$cur" in
		-*)
			COMPREPLY=( $( compgen -W "--path --help -h" -- "$cur" ) )
			;;
	esac

}

_oci-runtime-tool_help() {
	local counter=$(__oci-runtime-tool_pos_first_nonflag)
	if [ $cword -eq $counter ]; then
		COMPREPLY=( $( compgen -W "${commands[*]}" -- "$cur" ) )
	fi
}

_oci-runtime-tool_generate() {
	local options_with_args="
		--apparmor
		--arch
		--args
		--bind
		--cap-add
		--cap-drop
		--cgroups-path
		--cwd
		--device-add
		--device-remove
		--env
		--env-file
		--gid
		--gidmappings
		--groups
		--hostname
		--label
		--linux-cpu-shares
		--linux-cpu-period
		--linux-cpu-quota
		--linux-cpus
		--linux-mem-kernel-limit
		--linux-mem-kernel-tcp
		--linux-mem-limit
		--linux-mem-reservation
		--linux-mem-swap
		--linux-mem-swappiness
		--linux-mems
		--linux-namespace-add
		--linux-namespace-remove
		--linux-network-classid
		--linux-network-priorities
		--linux-pids-limit
		--linux-realtime-period
		--linux-realtime-runtime
		--masked-paths
		--mount-cgroups
		--mount-label
		--oom-score-adj
		--os
		--output
		--poststart
		--poststop
		--prestart
		--readonly-paths
		--rootfs-path
		--rootfs-propagation
		--rlimits-add
		--rlimits-remove
		--seccomp-allow
		--seccomp-arch
		--seccomp-default
		--seccomp-default-force
		--seccomp-errno
		--seccomp-kill
		--seccomp-remove
		--seccomp-trace
		--seccomp-trap
		--selinux-label
		--sysctl
		--template
		--tmpfs
		--uid
		--uidmappings
	"

	local boolean_options="
		--device-remove-all
		--disable-oom-kill
		--help -h
		--linux-namespace-remove-all
		--no-new-privileges
		--privileged
		--rlimits-remove-all
		--rootfs-readonly
		--seccomp-only
		--seccomp-remove-all
		--tty
	"

	local all_options="$options_with_args $boolean_options"

	case "$prev" in
		--arch)
			__oci-runtime-tool_complete_arches
			return
			;;

		--cap-add|--cap-drop)
			__oci-runtime-tool_complete_capabilities
			return
			;;

		--env|-e)
			COMPREPLY=( $( compgen -e -- "$cur" ) )
			__oci-runtime-tool_nospace
			return
			;;

		--env-file)
			_filedir
			__oci-runtime-tool_nospace
			return
			;;

		--gid)
			_gids
			return
			;;

		--groups)
			COMPREPLY=( $( compgen -W "$( __oci-runtime-tool_groups )" -- "$cur" ) )
			__oci-runtime-tool_nospace
			return
			;;

		--mount-cgroups)
			COMPREPLY=( $( compgen -W "no ro rw" -- "$cur" ) )
			return
			;;

		--os)
			COMPREPLY=( $( compgen -W "linux windows" -- "$cur" ) )
			return
			;;

		--poststart|--poststop|--prestart)
			COMPREPLY=( $( compgen -W "$( __oci-runtime-tool_hooks )" -- "$cur" ) )
			__oci-runtime-tool_nospace
			return
			;;

		--root-propagation)
			__oci-runtime-tool_complete_propagations
			return
			;;

		--rootfs|--tmpfs|--bind|--cwd)
			case "$cur" in
				*:*)
					# TODO somehow do _filedir for stuff inside the image, if it's already specified (which is also somewhat difficult to determine)
					;;
				'')
					COMPREPLY=( $( compgen -W '/' -- "$cur" ) )
					__oci-runtime-tool_nospace
					;;
				*)
					_filedir
					__oci-runtime-tool_nospace
					;;
			esac
			return
			;;

		--seccomp-arch)
			__oci-runtime-tool_complete_seccomp_arches
			return
			;;

		--seccomp-default)
			__oci-runtime-tool_complete_seccomp_actions
			return
			;;

		--uid)
			_uids
			return
			;;
	esac

	case "$cur" in
		-*)
			COMPREPLY=( $( compgen -W "$all_options" -- "$cur" ) )
			;;
	esac
}

_oci-runtime-tool() {
	local previous_extglob_setting=$(shopt -p extglob)
	shopt -s extglob

	local commands=(
		validate
		generate
	)

	COMPREPLY=()
	local cur prev words cword
	_get_comp_words_by_ref -n : cur prev words cword

	local command='oci-runtime-tool' command_pos=0 subcommand_pos
	local counter=1
	while [ $counter -lt $cword ]; do
		case "${words[$counter]}" in
			-*)
				;;
			=)
				(( counter++ ))
				;;
			*)
				command="${words[$counter]}"
				command_pos=$counter
				break
				;;
		esac
		(( counter++ ))
	done

	local completions_func=_oci-runtime-tool_${command}
	declare -F $completions_func >/dev/null && $completions_func

	eval "$previous_extglob_setting"
	return 0
}

eval "$__oci-runtime-tool_previous_extglob_setting"
unset __oci-runtime-tool_previous_extglob_setting

complete -F _oci-runtime-tool oci-runtime-tool