#!/bin/sh

if [ "$(whoami)" != "root" ]; then
	echo "This script is intended to run as root. Exiting" >&2
	exit 1
fi

for cmd in lshw jq; do
	if ! command -v $cmd > /dev/null; then
		echo "Please install $cmd. Exiting." >&2
		exit 1
	fi
done

if [ "$1" = "" ]; then
	echo "Usage: export-hardware.sh PATH_TO_OUTPUT" >&2
	exit 1
fi

output=$1
if [ -d "$1" ]; then
	echo "$1 is a directory and cannot be used as output. Exiting." >&2
	exit 1
fi

# We extract hardware details only once, as it can be somewhat expensive/slow.
echo "Extracting hardware informations.... "
hardware=$(lshw -json)
hostname=$(hostname --short)
components=$(echo "$hardware" | jq -r -c '..|.children?|select(.!=null)|.[]')
echo "--- OK"

print_server_component () {
	class=$(echo "$@"| jq -j -c .class)
	if echo "system processor memory power bus" | grep -w -q "$class"; then
		# Motherboards are 'bus' class and what **seem** to be consistent (from a
		# server + my laptop) 'Motherboard' description.
		if [ "$class" = "bus" ] && [ "$(echo "$@"| jq -j -c .description)" != "Motherboard" ]; then
			return
		fi

		serial=$(echo "$@"| jq -j -c '.serial // "-"')
		name='\(.description // .product)'
		manufacturer='\(.vendor // "-")'
		model='\(.product // "-")'

		case "$class" in
			"power")
				name="$name (slot: \\(.slot // \"-\"))"
				;;
			"system")
				# Ignore irrelevant PnP (and probably others) devices.
				if [ "$serial" = "-" ]; then
					return
				fi
				;;
			"memory")
			# Ignore CPU cache (= memory entries without serial number).
			if [ "$serial" = "-" ]; then
				return
			fi

			# Extract size of RAM sticks.
			units=$(echo "$@"| jq -j -c .units)
			size=$(echo "$@"| jq -j -c .size)
			if [ "$units" = "bytes" ]; then
				model="\(.product) ($(((size / 1024 / 1024 / 1024 ))) GB)"
			else
				model='\(.product) (\(.size) \(.units),)'
			fi
			;;
		esac

		echo "$@" | jq -j -c ".|\"| $class | $name | $manufacturer | $model | $serial | \n\""
	fi
}

get_disk_details () {
	product=$(echo "$@" | jq -j -c .product)
	size=$(echo "$@" | jq -j -c .size)
	units=$(echo "$@" | jq -j -c .units)
	serial=$(echo "$@" | jq -j -c .serial)

	if [ "$units" = "bytes" ]; then
		size=$(((size / 1024 / 1024 / 1024)))
		units='GB'
	fi

	cat <<- EOF
		$product ($serial, $size $units)
	EOF
}

### Output ###

touch "$output"

echo "Generating system section... "
cat <<- EOF > "$output"
	# Host: $hostname

	Extracted on $(date -I) by the [hardware-to-mkd script](https://code.recycled.cloud/RecycledCloud/tools/src/branch/master/hardware-to-mkd).

	## System

	| Class | Name | Manufacturer | Model | Serial |
	|-------|------|--------------|-------|--------|
	$(print_server_component "$hardware")
EOF

echo "$components" | while read -r component; do
print_server_component "$component" >> "$output"
done
echo "--- OK"

echo "Generating disks section... "
cat <<- EOF >> "$output"

	## Disks

	| Disk |
	|------|
EOF
	echo "$components" | while read -r component; do
	class=$(echo "$component"| jq -j -c .class)
	if [ "$class" = "disk" ]; then
		echo "| $(get_disk_details "$component") |" >> "$output"
	fi
done
echo "--- OK"

echo "Generating NICs section... "
cat <<- EOF >> "$output"
	## NICs

	| Interface | MAC |
	|-----------|-----|
EOF

echo "$components" | while read -r component; do
	class=$(echo "$component"| jq -j -c .class)
	if [ "$class" = "network" ]; then
		serial=$(echo "$component"| jq -j -c '.serial // "-"')
		iface=$(ip -j l | jq -r -c ".[] | select(.address == \"$serial\") | .ifname")
		echo "| $iface | $serial |" >> "$output"
	fi
done

echo "--- OK"