#!/usr/bin/env bash
# Self-update miaur from its Git repository

# Detect install prefix from the running binary location.
# Prints: user|/path/prefix   or   system|/path/prefix
miaur_detect_prefix() {
	case "$MIAUR_HOME" in
	"${HOME}/.local/share/miaur")
		printf 'user|%s\n' "${HOME}/.local"
		;;
	/usr/local/share/miaur)
		printf 'system|%s\n' /usr/local
		;;
	*)
		# Dev checkout or custom layout — default to a user install
		printf 'user|%s\n' "${HOME}/.local"
		;;
	esac
}

# Read MIAUR_VERSION=... from a common.sh path
_miaur_read_version_file() {
	local file=$1
	[[ -f $file ]] || return 1
	local line
	line=$(grep -E '^MIAUR_VERSION=' "$file" | head -n1) || return 1
	line=${line#MIAUR_VERSION=}
	line=${line#\"}
	line=${line%\"}
	line=${line#\'}
	line=${line%\'}
	printf '%s\n' "$line"
}

# Install tree from SRC into PREFIX (user|system via $1 mode)
_miaur_install_tree() {
	local mode=$1
	local prefix=$2
	local src=$3
	local share="${prefix}/share/miaur"
	local binlink="${prefix}/bin/miaur"

	[[ -f $src/miaur && -d $src/lib ]] || die "incomplete source tree: $src"

	_run() {
		if [[ $mode == system ]]; then
			as_root "$@"
		else
			"$@"
		fi
	}

	msg "Installing to ${share}"
	_run mkdir -p "$share" "${prefix}/bin"
	_run rm -rf "$share"
	_run mkdir -p "$share"
	_run cp -a "$src/miaur" "$src/lib" "$share/"
	if [[ -d $src/completions ]]; then
		_run cp -a "$src/completions" "$share/"
	fi
	if [[ -d $src/config ]]; then
		_run cp -a "$src/config" "$share/"
	fi
	_run chmod 755 "$share/miaur"
	_run ln -sfn "$share/miaur" "$binlink"

	if [[ -d $src/completions ]]; then
		if [[ $mode == user ]]; then
			mkdir -p "${HOME}/.local/share/bash-completion/completions"
			cp -f "$src/completions/miaur.bash" \
				"${HOME}/.local/share/bash-completion/completions/miaur" 2>/dev/null || true
		else
			if [[ -d /usr/share/bash-completion/completions ]]; then
				as_root cp -f "$src/completions/miaur.bash" \
					/usr/share/bash-completion/completions/miaur 2>/dev/null || true
			fi
		fi
	fi

	printf '%s\n' "$binlink"
}

# Fetch latest sources into a temp dir; prints path to clone
_miaur_fetch_latest() {
	local repo=$1
	local branch=$2
	local tmp
	tmp=$(mktemp -d)
	# Caller cleans up via SELF_UPDATE_TMP
	SELF_UPDATE_TMP=$tmp
	msg2 "Cloning ${repo} (${branch})..."
	${MIAUR_GIT} clone --depth 1 --branch "$branch" "$repo" "$tmp/miaur" \
		|| die "failed to clone ${repo} (branch ${branch}); set RepoUrl / MIAUR_REPO if you forked"
	[[ -f $tmp/miaur/miaur && -d $tmp/miaur/lib ]] || die "cloned tree looks incomplete"
	printf '%s\n' "$tmp/miaur"
}

cmd_self_update() {
	need_cmd git

	local repo=${MIAUR_REPO:-https://github.com/WHC2006/miaur.git}
	local branch=${MIAUR_BRANCH:-main}
	local info mode prefix
	info=$(miaur_detect_prefix)
	mode=${info%%|*}
	prefix=${info#*|}

	local old_ver=${MIAUR_VERSION}
	msg "Current version: v${old_ver}"
	msg2 "Install prefix: ${prefix} (${mode})"
	msg2 "Source: ${repo} @ ${branch}"

	if [[ $MIAUR_HOME != "${prefix}/share/miaur" ]]; then
		warn "Running from ${MIAUR_HOME}; update will install into ${prefix}/share/miaur"
	fi

	confirm_ask "Update miaur from Git?" || {
		warn "Cancelled by user"
		return 1
	}

	SELF_UPDATE_TMP=
	# shellcheck disable=SC2064
	trap '[[ -n ${SELF_UPDATE_TMP:-} ]] && rm -rf "$SELF_UPDATE_TMP"; sudoloop_stop' RETURN

	local src new_ver binlink
	src=$(_miaur_fetch_latest "$repo" "$branch")
	new_ver=$(_miaur_read_version_file "$src/lib/common.sh") || new_ver=unknown

	if [[ $new_ver == "$old_ver" ]]; then
		msg "Remote reports the same version (v${new_ver}); reinstalling anyway"
	else
		msg "Updating: v${old_ver} -> v${new_ver}"
	fi

	if [[ $mode == system ]]; then
		sudoloop_start
	fi

	binlink=$(_miaur_install_tree "$mode" "$prefix" "$src")

	msg "Done: ${binlink}"
	if [[ -x $binlink ]]; then
		"$binlink" -V
	fi
}