nix/home/program/bash/module/Archive.nix

{ ... }: {
	text = ''
		export _archive_pattern="_[0-9]{12}-[[:alnum:]]{40}"
		export _archive_pattern_compressed="_[0-9]{12}-[[:alnum:]]{40}\.t(ar|gz|xz)$"
		export _archive_pattern_fast="_[0-9]{12}-[[:alnum:]]{40}\.tar$"

		# Archive using multiple threads. Uses 75% of free RAM.
		# All directories by default.
		# Supports .archiveignore exclude file.
		# Usage: archive [DIRS]
		function archive() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=($(_ls_dir))

			process() {
				# Skip if already an archive.
				_is_archive "''${target}" && {
					_iterate_skip "Already an archive."
					return 0
				};

				# Cut full paths.
				[[ "''${target##*/}" = "" ]] || target="''${target##*/}"

				local date=$(_archive_date)

				# Parse name.
				local name=$(parse_pascal ''${target})

				# Exclude support.
				local exclude=""
				[[ -f ".archiveignore" ]] && exclude="--exclude-from=.archiveignore"
				[[ -f "''${target}/.archiveignore" ]] && exclude="--exclude-from=''${target}/.archiveignore"

				# Create archive.
				local hash=$(tar ''${exclude} -c ''${target} | pv -s $(/usr/bin/env du -sb ''${target} | awk '{print $1}') | xz -9e --threads=0 --memlimit=$(_archive_memlimit) | tee ''${name}.txz | sha1sum | cut -d\  -f1)

				# Append hash to target name.
				local new_name="''${name}_''${date}-''${hash}.txz"
				mv -- ''${name}.txz ''${new_name} && echo ''${new_name}
			}

			_iterate_targets process ''${targets[@]}
		}

		# Creates a simple archive.
		# If it is a file, it just reformats file name to match archive name.
		# For dirs, it first creates a tar archive.
		# All files by default.
		# Usage: archive_fast [DIRS]
		function archive_fast() {
			local IFS=$'\n'
			local targets=("''${@}")
			[[ "''${targets}" = "" ]] && targets=($(_ls_file))

			process() {
				# Skip if already an archive.
				_is_archive "''${target}" && {
					_iterate_skip "Already an archive."
					return 0
				};

				# Cut full paths.
				[[ "''${target##*/}" = "" ]] || target="''${target##*/}"

				# Start timestamp.
				local date=$(_archive_date)

				# Exclude support.
				local exclude
				[[ -f ".archiveignore" ]] && exclude="--exclude-from=.archiveignore"
				[[ -f "''${target}/.archiveignore" ]] && exclude="--exclude-from=''${target}/.archiveignore"

				local name
				local extension

				if [[ -d "''${target}" ]]; then
					name=$(parse_pascal "''${target}")

					# Create archive.
					local hash=$(tar ''${exclude} -c "''${target}" | pv -s $(/usr/bin/env du -sb "''${target}" | awk '{print $1}') | tee "''${name}".tar | sha1sum | cut -d\  -f1)

					# Append hash to target name.
					local new_name="''${name}_''${date}-''${hash}.tar"
					mv -- "''${name}".tar ''${new_name} && echo ''${new_name}
				else
					name=$(parse_pascal "''${target%.*}")
					extension=".''${target##*.}"

					# Check if extension matches name, then drop it.
					[[ "''${extension}" = ".''${target%.*}" ]] && extension=""

					local hash=$(pv "''${target}" | sha1sum | cut -d\  -f1)
					local new_name="''${name}_''${date}-''${hash}''${extension}"
					mv -- "''${target}" "''${new_name}" && echo ''${new_name}
				fi
			}

			_iterate_targets process ''${targets[@]}
		}

		# Check archives integrity.
		# Checks all archives by default.
		# Usage: archive_check [FILES]
		function archive_check() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=($(_ls_archive))

			process() {
				_archive_check "''${target}"
			}

			_iterate_targets process ''${targets[@]}
		}

		# Delete old versions of an archive.
		# All archives with 1 version by default.
		# Usage: archive_prune [NAME] [VERSIONS]
		function archive_prune() {
			local IFS=$'\n'
			local targets=(''${1})
			local versions=''${2}

			[[ "''${targets}" = "" ]] && targets=($(_archive_names))
			[[ "''${versions}" = "" ]] && versions=1

			if [[ ''${#} -gt 2 ]]; then
				help archive_prune
				return 2
			fi

			process() {
				local prune=($(ls | grep -E "^''${target}''${_archive_pattern}" | sort -r | sed -e "1,''${versions}d"))

				for archive in ''${prune[@]}; do
					rm -- "''${archive}" && echo "''${archive}"
				done
			}

			_iterate_targets process ''${targets[@]}
		}

		# Delete specified or all archive files.
		# Usage: archive_rm [FILES]
		function archive_rm() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=($(_ls_archive))

			process() {
				rm -- "''${target}" && echo "''${target}"
			}

			_iterate_targets process ''${targets[@]}
		}

		# Recompress previously created archive_fast with better compression.
		# Usage: archive_compress [FILES]
		function archive_compress() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=$(_ls_archive_fast)

			process() {
				local data=($(_archive_parse "''${target}"))
				local tmp="''${data[0]}.txz"

				# Check that old format.
				if [[ "''${data[3]}" != "tar" ]]; then
					_iterate_skip "Not in .tar format!"
					return 0
				fi

				# Check integrity.
				_archive_check "''${target}" || return 1

				# Recompress.
				local hash=$(pv "''${target}" | xz -9e --threads=0 --memlimit=$(_archive_memlimit) | tee "''${tmp}" | sha1sum | cut -d\  -f1)

				# Rename.
				local new_name="''${data[0]}_''${data[1]}-''${hash}.txz"
				mv -- ''${tmp} ''${new_name} && rm ''${target} && echo ''${new_name}
			}

			_iterate_targets process ''${targets[@]}
		}

		# Rename archives.
		# If no name specified, it simplifies archive's name.
		# If no archives specified, apply to all archives.
		# Usage: archive_name [ARCHIVE] [NAME]
		function archive_name() {
			local IFS=$'\n'
			local targets="''${1}"
			local name="''${2}"
			[[ "''${targets}" = "" ]] && targets=($(_ls_archive))

			process() {
				# Simplify name by default.
				if [[ "''${name}" = "" || ''${count} -gt 1 ]]; then
					name="''${target%_*}"
					name="$(parse_pascal ''${name})"
				fi

				# Remove old name.
				local data="''${target##*_}"
				local new_name="''${name}_''${data}"

				# Check for the same name.
				[[ "''${target}" = "''${new_name}" ]] && return 0

				# Check for existing target.
				if [[ -f "''${new_name}" ]]; then
					_error "''${new_name}: Already exists!"
					return 1
				fi

				# Rename.
				mv -- ''${target} ''${new_name} && echo ''${new_name}
			}

			_iterate_targets process ''${targets[@]}
		}

		# Extract previously created archive with checksum validation.
		# Supports unarchiving exact paths from the remote machines (rsync syntax).
		# Usage: unarchive [HOST:FILES]
		function unarchive() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=$(_ls_archive_compressed)

			process() {
				# Validate.
				# _archive_check "''${target}" || return 1
				if ! _is_compressed_archive "''${target}"; then
					_iterate_skip "Not a compressed archive."
					return 0
				fi

				# Remote archives.
				local remote
				local file="''${target}"

				if [[ "''${target//\\:/}" == *:* ]]; then
					local host="''${target%%:*}"
					file="''${target#*:}"
					remote=(trysudo ssh ''${host})
				fi

				# Extract.
				case "''${file##*.}" in
					"txz")
						''${remote[@]} pv -f ''${file} | xz -d | tar -xf -
						;;
					"tar")
						''${remote[@]} pv -f ''${file} | tar -xf -
						;;
					"tgz")
						''${remote[@]} pv -f ''${file} | gzip -d | tar -xf -
						;;
				esac
			}

			_iterate_targets process ''${targets[@]}
		}

		# Change archive's filesystem time to match creation date.
		# Usage: archive_touch [FILES]
		function archive_touch() {
			local IFS=$'\n'
			local targets=(''${@})
			[[ "''${targets}" = "" ]] && targets=$(_ls_archive)

			process() {
				local data=($(_archive_parse "''${target}"))
				local date=''${data[1]}
				touch -t ''${date} -- ''${target}
			}

			_iterate_targets process ''${targets[@]}
		}

		# Parse archive file name to get: name, date, hash and format.
		# Usage: _archive_parse <FILENAME>
		function _archive_parse() {
			local input="''${1}"
			local name="''${input%_*}"
			local format="''${input##*.}"
			local data="''${input##*_}"; data="''${data%.*}"
			local date="''${data%%-*}"
			local hash="''${data##*-}"

			# No extension if no dots.
			[[ "''${input}" = *\.* ]] || format=""

			echo "''${name}"
			echo "''${date}"
			echo "''${hash}"
			echo "''${format}"
		}

		# Autocomplete for archive_name function.
		# First arg is the archives list, second one is selected archive's current name.
		function _comp_archive_name() {
			local IFS=$'\n'
			COMPREPLY=()

			local cur="''${COMP_WORDS[COMP_CWORD]}"
			local prev="''${COMP_WORDS[COMP_CWORD-1]}"
			local command="''${COMP_WORDS[0]}"

			if [[ "''${prev}" = "''${command}" ]]; then
				COMPREPLY=( $(compgen -W "$(ls | grep -E ''${_archive_pattern})" -- ''${cur}) )
				return 0
			else
				local data=($(_archive_parse ''${prev}))
				local name="''${data[0]}"
				COMPREPLY=( $(compgen -W "''${name}" -- ''${cur}) )
				return 0
			fi
		}

		# Autocomplete with archives in current dir.
		function _comp_archive_grep() {
			_autocomplete_grep ''${_archive_pattern}
		}

		# Autocomplete with fast archives in current dir.
		function _comp_archive_grep_fast() {
			_autocomplete_grep ''${_archive_pattern_fast}
		}

		# Get date for a new archive.
		function _archive_date() {
			date +%Y%m%d%H%M
		}

		# Get names of all archives.
		function _archive_names() {
			local IFS=$'\n'
			local archives=($(_ls_archive))
			local names=()

			for archive in ''${archives[@]}; do
				local data=($(_archive_parse ''${archive}))
				names+=(''${data[0]})
			done

			# Remove copies.
			names=($(printf '%s\n' "''${names[@]}" | sort -u))

			printf '%s\n' "''${names[@]}"
		}

		# Autocomplete with names of all archives.
		function _comp_archive_names() {
			_autocomplete_first $(_archive_names)
		}

		# Check if file is an archive.
		function _is_archive() {
			local out=$(echo "''${*}" | grep -E ''${_archive_pattern})

			[[ "''${out}" != "" ]]
		}

		# Check if file is a compressed archive.
		function _is_compressed_archive() {
			local out=$(echo "''${*}" | grep -E ''${_archive_pattern_compressed})

			[[ "''${out}" != "" ]]
		}

		# List all archives.
		function _ls_archive() {
			ls | grep -E ''${_archive_pattern}
		}

		# List fast archives.
		function _ls_archive_fast() {
			ls | grep -E ''${_archive_pattern_fast}
		}

		# List fast archives.
		function _ls_archive_compressed() {
			ls | grep -E ''${_archive_pattern_compressed}
		}

		# Filter input for archives only.
		function _filter_archive() {
			grep -E ''${_archive_pattern}
		}

		function _archive_memlimit() {
			local mem_free=$(_mem_free)
			local mem_limit=$((mem_free*3/4))

			echo "''${mem_limit}MiB"
		}

		function _archive_check() {
			# Extract hash from name.
			local data=($(_archive_parse ''${target}))
			local saved=''${data[2]}

			# Calculate actual hash.
			local actual=$(pv ''${target} | sha1sum | cut -d\  -f1)

			# Compare hashes.
			[[ "''${actual}" = "''${saved}" ]] || _error "Archive check failed."
		}

		# complete -o filenames -F _comp_archive_grep        archive_check unarchive archive_rm archive_touch
		# complete -o filenames -F _comp_archive_grep_fast   archive_xz
		complete -o filenames -F _comp_archive_name        archive_name
		complete -o filenames -F _comp_archive_names       archive_prune
	'';
}